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早野 順一郎ハヤノ ジュンイチロウ

所属部署医学研究科医学・医療教育学分野
職名教授
メールアドレス
ホームページURLhttp://hbsl.jp/
生年月日
Last Updated :2020/07/02

研究者基本情報

学位

  • 医学博士
  • PhD, Nagoya City University Graduate School of Medical Sciences

所属学協会

  • 日本生理人類学会

研究活動情報

研究分野

  • 情報通信, 生命、健康、医療情報学, 生体・生命情報学
  • ライフサイエンス, 循環器内科学
  • ライフサイエンス, 生体材料学
  • ライフサイエンス, 生体医工学

研究キーワード

    情動, 居眠り, 生体情報, 時系列解析, 健康科学, 情報科学, 睡眠時無呼吸, 生体信号処理, ビッグデータ, 心拍変動

論文

  • Evaluation of nocturnal heart rate variability for strenuous exercise day using wearable photoelectric pulse wave sensor., Yutaka Yoshida, Emi Yuda, Kiyoko Yokoyama, Junichiro Hayano, Journal of exercise rehabilitation, 14, (4) 633 - 637,   2018年08月, 査読有り, In this study, we examined whether or not the strenuous exercise in the evening change nocturnal heart rate variability (HRV) and recovers. Subjects were 8 healthy men belonging to the mature futsal team (age: 35±3 years) and Futsal was held from 5:00 p.m. to 6:30 p.m. on Sunday. Pulse waves during sleeping were measured at home on exercise day and on control day. The mean pulse interval (MPI), standard deviation pulse interval (SDPI), low frequency component (LF, 0.04-0.15 Hz), high frequency component (HF, 0.15-0.45 Hz) and the ratio of LF to HF (LF/HF) were calculated from pulse interval time series every 30 min. As a result, MPI, SDPI, LF, HF of exercise day were significantly lower than control day (P<0.0001). LF/HF of exercise day was significantly higher than control day (P<0.05). Regarding change of HRV for every 30 min, MPI (P<0.05), SDPI (P=0.0003), LF (P=0.0038), HF (P<0.05) were observed significant changes. MPI and HF before wake-up did not reach the level of control day. It is thought that strenuous exercise in the evening promotes sympathetic nervous activity during night sleep and suggesting that pulse rate and HRV have not recovered by the wake-up time.
  • Impacts of sleeping time during the day on the timing and level of basal heart rate: analysis of ALLSTAR big data, Yuda E, Yoshida Y, Hayano J, Wireless Networks,   2018年06月, 査読有り
  • Increase in random component of heart rate variability coinciding with developmental and degenerative stages of life., Junichiro Hayano, Kei Ohashi, Yutaka Yoshida, Emi Yuda, Tooru Nakamura, Ken Kiyono, Yoshiharu Yamamoto, Physiological measurement, 39, (5) 054004 - 054004,   2018年05月25日, 査読有り, OBJECTIVE: To adapt to a new environment or situation, biological systems explore the most convenient state while moving between attractors by the force of random fluctuation. From this concept, the random component in physiological signals is assumed to increase during developmental and degenerative stages of life. To examine this hypothesis, we measured the age-dependent changes in the random component of heart rate variability (HRV) in 24-h electrocardiography (ECG) big data and in patients with a developmental disorder (DD). APPROACH: We measured separately regulated and random components of HRV with autoregressive (AR) model fitting, by which the ratio of random component as the fractional variance of AR residual time series. From the ALLSTAR database of about 304 000 ambulatory 24-h ECGs, we randomly extracted the data of 1930 men and 1987 women uniformly for all ages from 0 to 100 years old (100 cases per 5-year strata for each sex). Data were also obtained from male pediatric patients with DD (age 10-15 years). MAIN RESULTS: While the variance of the regulated component of HRV increased from age 0 to 20, decreased with age until 40, and reached a plateau in both sexes, the ratio of the random component was high at birth, decreased with age until 35 in men and 30 in women, and increased again after 75 in men and 85 in women (P  <  0.0001 for all). In patients with a DD, the ratio of the random component was significantly lower than that in age-and-sex matched subjects in the database. SIGNIFICANCE: We found that the ratio of the random component of HRV is increased during developmental and degenerative stages of life and that it may be reduced in DD patients during their development.
  • Scattering Transform of Heart Rate Variability for the Prediction of Ischemic Stroke in Patients with Atrial Fibrillation., Roberto Leonarduzzi, Patrice Abry, Herwig Wendt, Ken Kiyono, Yoshiharu Yamamoto, Eiichi Watanabe, Junichiro Hayano, Methods of information in medicine, 57, (3) 141 - 145,   2018年05月, 査読有り, BACKGROUND: Atrial fibrillation (AF) is an identified risk factor for ischemic strokes (IS). AF causes a loss in atrial contractile function that favors the formation of thrombi, and thus increases the risk of stroke. Also, AF produces highly irregular and complex temporal dynamics in ventricular response RR intervals. Thus, it is hypothesized that the analysis of RR dynamics could provide predictors for IS. However, these complex and nonlinear dynamics call for the use of advanced multiscale nonlinear signal processing tools. OBJECTIVES: The global aim is to investigate the performance of a recently-proposed multiscale and nonlinear signal processing tool, the scattering transform, in predicting IS for patients suffering from AF. METHODS: The heart rate of a cohort of 173 patients from Fujita Health University Hospital in Japan was analyzed with the scattering transform. First, p-values of Wilcoxon rank sum tests were used to identify scattering coefficients achieving significant (univariate) discrimination between patients with and without IS. Second, a multivariate procedure for feature selection and classification, the Sparse Support Vector Machine (S-SVM), was applied to predict IS. RESULTS: Groups of scattering coefficients, located at several time-scales, were identified as significantly higher (p-value < 0.05) in patients who developed IS than in those who did not. Though the overall predictive power of these indices remained moderate (around 60 %), it was found to be much higher when analysis was restricted to patients not taking antithrombotic treatment (around 80 %). Further, S-SVM showed that multivariate classification improves IS prediction, and also indicated that coefficients involved in classification differ for patients with and without antithrombotic treatment. CONCLUSIONS: Scattering coefficients were found to play a significant role in predicting IS, notably for patients not receiving antithrombotic treatment. S-SVM improves IS detection performance and also provides insight on which features are important. Notably, it shows that AF patients not taking antithrombotic treatment are characterized by a slow modulation of RR dynamics in the ULF range and a faster modulation in the HF range. These modulations are significantly decreased in patients with IS, and hence have a good discriminant ability.
  • Acute effects of endurance exercise on nocturnal autonomic functions in sedentary subjects: a pilot study., Emi Yuda, Yoshifumi Moriyama, Toshihiko Mori, Yutaka Yoshida, Makoto Kawahara, Junichiro Hayano, Journal of exercise rehabilitation, 14, (1) 113 - 117,   2018年02月, 査読有り, Nocturnal heart rate variability (HRV) is thought to reflect healthy recovery function of the autonomic nervous system. Although exercise is recommended for health promotion, exercise itself decreases HRV. We studied acute effect of daytime exercise on nocturnal HRV in 5 healthy adults (age, 22-40 years; 2 female subjects) without regular exercise habit. Using a treadmill, they performed 30-min walking at 4 km/hr and 30-min running at 9 km/hr from 11 a.m. on different days at an interval of 2 weeks. On these days and a day without exercise (control), Holter electrocardiograms were recorded from 9 a.m. for 24 hr. The amplitudes of low-frequency (LF, 0.04-0.15 Hz) and high-frequency (HF, 0.15-0.45 Hz) components of HRV were measured continuously by complex demodulation and were averaged over periods of 11:00-11:30 a.m., 3 hr after going to bed, and time in bed at night. Exercise intensities of the walking and running were at 10% to 44% and 55% to 67% of heart rate reserve, respectively. During exercise, heart rate increased and LF and HF amplitudes decreased with exercise intensity. Nocturnal heart rate and LF and HF amplitude, however, showed no consistent changes with exercise intensity and their averages on the days of walking and running did not differ significantly from those of the control day. In conclusion, 30-min walking and running exercises performed in the morning had no significant acute effects on nocturnal heart rate or HRV.
  • Sleep stage classification by a combination of actigraphic and heart rate signals, Emi Yuda, Yutaka Yoshida, Ryujiro Sasanabe, Haruhito Tanaka, Toshiaki Shiomi, Junichiro Hayano, Journal of Low Power Electronics and Applications, 7,   2017年12月01日, © 2017 by the authors. Licensee MDPI, Basel, Switzerland. Although heart rate variability and actigraphic data have been used for sleep-wake or sleep stage classifications, there are few studies on the combined use of them. Recent wearable sensors, however, equip both pulse wave and actigraphic sensors. This paper presents results on the performance of sleep stage classification by a combination of heart rate and actigraphic signals. We studied 40,643 epochs (length 3 min) of polysomnographic data in 289 subjects. A combined model, consisting of autonomic functional indices from heart rate variability and body movement indices derived from actigraphic data, discriminated non-rapid-eye-movement (REM) sleep from waking/REM sleep with 76.9% sensitivity, 74.5% specificity, 75.8% accuracy, and a Cohen’s kappa of 0.514. The combination was also useful for discriminating between REM sleep and waking at 77.2% sensitivity, 72.3% specificity, 74.5% accuracy, and a kappa of 0.491.
  • Blunted cyclic variation of heart rate predicts mortality risk in post-myocardial infarction, end-stage renal disease, and chronic heart failure patients., Junichiro Hayano, Fumihiko Yasuma, Eiichi Watanabe, Robert M Carney, Phyllis K Stein, James A Blumenthal, Petros Arsenos, Konstantinos A Gatzoulis, Hiroshi Takahashi, Hideki Ishii, Ken Kiyono, Yoshiharu Yamamoto, Yutaka Yoshida, Emi Yuda, Itsuo Kodama, Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology, 19, (8) 1392 - 1400,   2017年08月01日, 査読有り, Aims: Cyclic variation of heart rate (CVHR) associated with sleep-disordered breathing is thought to reflect cardiac autonomic responses to apnoeic/hypoxic stress. We examined whether blunted CVHR observed in ambulatory ECG could predict the mortality risk. Methods and results: CVHR in night-time Holter ECG was detected by an automated algorithm, and the prognostic relationships of the frequency (FCV) and amplitude (ACV) of CVHR were examined in 717 patients after myocardial infarction (post-MI 1, 6% mortality, median follow-up 25 months). The predictive power was prospectively validated in three independent cohorts: a second group of 220 post-MI patients (post-MI 2, 25.5% mortality, follow-up 45 months); 299 patients with end-stage renal disease on chronic haemodialysis (ESRD, 28.1% mortality, follow-up 85 months); and 100 patients with chronic heart failure (CHF, 35% mortality, follow-up 38 months). Although CVHR was observed in ≥96% of the patients in all cohorts, FCV did not predict mortality in any cohort. In contrast, decreased ACV was a powerful predictor of mortality in the post-MI 1 cohort (hazard ratio [95% CI] per 1 ln [ms] decrement, 2.9 [2.2-3.7], P < 0.001). This prognostic relationship was validated in the post-MI 2 (1.8 [1.4-2.2], P < 0.001), ESRD (1.5 [1.3-1.8], P < 0.001), and CHF (1.4 [1.1-1.8], P = 0.02) cohorts. The prognostic value of ACV was independent of age, gender, diabetes, β-blocker therapy, left ventricular ejection fraction, sleep-time mean R-R interval, and FCV. Conclusion: Blunted CVHR detected by decreased ACV in a night-time Holter ECG predicts increased mortality risk in post-MI, ESRD, and CHF patients.
  • Exposure to blue light during lunch break: effects on autonomic arousal and behavioral alertness., Emi Yuda, Hiroki Ogasawara, Yutaka Yoshida, Junichiro Hayano, Journal of physiological anthropology, 36, (1) 30 - 30,   2017年07月11日, 査読有り, BACKGROUND: Exposures to melanopsin-stimulating (melanopic) component-rich blue light enhance arousal level. We examined their effects in office workers. Eight healthy university office workers were exposed to blue and orange lights for 30 min during lunch break on different days. We compared the effects of light color on autonomic arousal level assessed by heart rate variability (HRV) and behavioral alertness by psychomotor vigilance tests (PVT). Heart rate was higher and high-frequency (HF, 0.150.45 Hz) power of HRV was lower during exposure to the blue light than to orange light. No significant difference with light color was observed, however, in any HRV indices during PVT or in PVT performance after light exposure. SHORT CONCLUSION: Exposure to blue light during lunch break, compared with that to orange light, enhances autonomic arousal during exposure, but has no sustained effect on autonomic arousal or behavioral alertness after exposure.
  • Sodium balance, circadian BP rhythm, heart rate variability, and intrarenal renin-angiotensin-aldosterone and dopaminergic systems in acute phase of ARB therapy., Isobe-Sasaki Y, Fukuda M, Ogiyama Y, Sato R, Miura T, Fuwa D, Mizuno M, Matsuoka T, Shibata H, Ito H, Ono M, Abe-Dohmae S, Kiyono K, Yamamoto Y, Kobori H, Michikawa M, Hayano J, Ohte N, Physiological reports, 5, (11) ,   2017年06月, 査読有り
  • Prognostic Importance of Novel Oxygen Desaturation Metrics in Patients With Heart Failure and Central Sleep Apnea, Eiichi Watanabe, Ken Kimono, Shojiro Matsui, Virend K. Somers, Kan Sano, Junichiro Hayano, Tomohide Ichikawa, Mayumi Kawai, Masahide Harada, Yukio Ozaki, JOURNAL OF CARDIAC FAILURE, 23, (2) 131 - 137,   2017年02月, 査読有り, Background: Sleep-disordered breathing, particularly central sleep apnea (CSA), is highly prevalent in heart failure (HF) and an independent prognostic marker. We assessed the hypothesis that an increased hypoxemic burden during sleep may have greater prognostic value than the frequency of apneic and hypopneic episodes. Methods and Results: We prospectively conducted overnight cardiorespiratory polygraphy on consecutive HF patients referred to our hospital from 2008 to 2011. We studied CSA defined by an apnea-hypopnea index (AHI) of >= 5 events/h with >75% of all events being central in origin. We determined the AHI, proportion of the sleep time with SpO(2) <90% (T90%), and proportion of the recording time that 4% desaturation events occurred (4%POD). We studied 112 HF patients with either systolic or diastolic dysfunction. During a follow-up period of 37 +/- 25 months, 32 patients (29%) died. Nonsurvivors had a higher 4%POD compared with survivors (11 +/- 6.4% vs 19 +/- 13%; P=.001), but did not differ significantly from survivors regarding AHI and T90%. An adjusted logistic regression analysis revealed that the 4%POD was the best independent predictor of mortality. Conclusions: The 4%POD, a novel metric for the nocturnal hypoxemic burden, is an independent prognostic marker in HF patients affected by CSA.
  • Enhancement of autonomic and psychomotor arousal by exposures to blue wavelength light: importance of both absolute and relative contents of melanopic component., Emi Yuda, Hiroki Ogasawara, Yutaka Yoshida, Junichiro Hayano, Journal of physiological anthropology, 36, (1) 13 - 13,   2017年01月31日, 査読有り, BACKGROUND: Blue light containing rich melanopsin-stimulating (melanopic) component has been reported to enhance arousal level, but it is unclear whether the determinant of the effects is the absolute or relative content of melanopic component. We compared the autonomic and psychomotor arousal effects of melanopic-enriched blue light of organic light-emitting diode (OLED) with those of OLED lights with lesser absolute amount of melanopic component (green light) and with greater absolute but lesser relative content (white light). METHODS: Using a ceiling light consisting of 120 panels (55 × 55 mm square) of OLED modules with adjustable color and brightness, we examined the effects of blue, green, and white lights (melanopic photon flux densities, 0.23, 0.14, and 0.38 μmol/m2/s and its relative content ratios, 72, 17, and 14%, respectively) on heart rate variability (HRV) during exposures and on the performance of psychomotor vigilance test (PVT) after exposures in ten healthy subjects with normal color vision. For each of the three colors, five consecutive 10-min sessions of light exposures were performed in the supine position, interleaved by four 10-min intervals during which 5-min PVT was performed under usual fluorescent light in sitting position. Low-frequency (LF, 0.04-0.15 Hz) and high-frequency (HF, 0.15-0.40 Hz) power and LF-to-HF ratio (LF/HF) of HRV during light exposures and reaction time (RT) and minor lapse (RT >500 ms) of PVT were analyzed. RESULTS: Heart rate was higher and the HF power reflecting autonomic resting was lower during exposures to the blue light than the green and white lights, while LF/HF did not differ significantly. Also, the number of minor lapse and the variation of reaction time reflecting decreased vigilance were lower after exposures to the blue light than the green light. CONCLUSIONS: The effects of blue OLED light for maintaining autonomic and psychomotor arousal levels depend on both absolute and relative contents of melanopic component in the light.
  • SLEEP STAGE CLASSIFICATION BY COMBINATION OF ACTIGRAPHIC AND HEART RATE SIGNALS, Junichiro Hayano, Emi Yuda, Yutaka Yoshida, 2017 IEEE INTERNATIONAL CONFERENCE ON CONSUMER ELECTRONICS - TAIWAN (ICCE-TW),   2017年, 査読有り, This paper presents the performance of sleep stage classification by combination of actigraphic and heart rate signals. We studied 40,643 epochs (length 3 min) of polysomnographic data in 289 subjects. Body movement indices derived from actigraphic data and autonomic functional indices from heart rate variability were useful for discriminating between non-REM sleep and waking/REM sleep at 76.9% sensitivity and 74.5% specificity and between REM sleep and waking at 77.2% sensitivity and 72.3% specificity.
  • Fast algorithm of long-range cross-correlation analysis using Savitzky-Golay detrending filter and its application to biosignal analysis, 2017 INTERNATIONAL CONFERENCE ON NOISE AND FLUCTUATIONS (ICNF),   2017年, 査読有り
  • Life Style Modification by Peer Monitoring of Physical Activity., Emi Yuda, Akira Kurata, Yutaka Yoshida, Junichiro Hayano, Proceedings of the 14th EAI International Conference on Mobile and Ubiquitous Systems: Computing, Networking and Services, Melbourne, Australia, November 7-10, 2017., 520 - 522,   2017年, 査読有り
  • Comparison of emotional impacts of interaction with remote controlled plush media and those with video call applications., Emi Yuda, Hiroki Ogasawara, Yutaka Yoshida, Junichiro Hayano, IEEE 6th Global Conference on Consumer Electronics, GCCE 2017, Nagoya, Japan, October 24-27, 2017, 1 - 3,   2017年, 査読有り
  • Development of sleep-wake estimation algorithm using the wrist acceleration sensor., Yutaka Yoshida, Akira Kurata, Emi Yuda, Junichiro Hayano, IEEE 6th Global Conference on Consumer Electronics, GCCE 2017, Nagoya, Japan, October 24-27, 2017, 1 - 2,   2017年, 査読有り
  • Multiscale properties of instantaneous parasympathetic activity in severe congestive heart failure: A survivor vs non-survivor study., Gaetano Valenza, Herwig Wendt, Ken Kiyono, Junichiro, Hayano,Eiichi Watanabe, Yoshiharu Yamamoto, Patrice Abry,Riccardo Barbieri, 2017 39th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), Jeju Island, South Korea, July 11-15, 2017, 3761 - 3764,   2017年, 査読有り
  • Suppression of vagal cardiac modulation by blue light in healthy subjects., Emi Yuda, Hiroki Ogasawara, Yutaka Yoshida, Junichiro Hayano, Journal of physiological anthropology, 35, (1) 24 - 24,   2016年10月05日, 査読有り, BACKGROUND: In the contemporary life environments, our body is increasingly exposed to various sources of colored light, which may affect our physiological functions as non-image-forming effects. We examined the impacts of colored lights on the autonomic functions by the analysis of heart rate variability (HRV). METHODS: A lighting device consisting of four organic light-emitting diode (OLED) modules (55 × 55 mm2) with adjustable red-green-blue color was secured 24 cm above the eyes of subject lying supine in a light-shielded laboratory. Following a 15-min supine rest, electrocardiogram and respiration were measured continuously during 3-min darkness, 6-min colored OLED illumination, and 3-min darkness under paced breathing (15 breath/min). The measurements were repeated at a 45-min interval for red, green, and blue lights with melanopsin-stimulating photon flux density (MSPFD) of 0.00, 0.10, and 0.20 μmol/m2/s, respectively, in 12 healthy subjects (23 ± 2 years, two females). Additionally, the effects of blue lights with 0.20, 0.10, and 0.04 μmol/m2/s MSPFD were examined in four healthy subjects (25-39 years, two females). HRV was analyzed for low-frequency (LF, 0.04-0.15 Hz) and high-frequency (HF, 0.20-0.30 Hz) power and LF-to-HF ratio (LF/HF). RESULTS: Compared to darkness before lighting, HF power decreased (P < 0.001) and LF/HF increased (P = 0.024) during lighting on average of all color lights, whereas HF power showed a greater decrease with blue light than with red and green lights (P < 0.05 for both). The decrease in HF power lasted even during darkness after lighting (P < 0.001). HF power decreased with blue light with 0.20 μmol/m2/s MSPFD (P < 0.001) but not with that with 0.10 or 0.04 μmol/m2/s (P = 0.1 and 0.9, respectively). CONCLUSIONS: Vagal cardiac modulation is suppressed by OLED blue light in healthy subjects most likely through melanopsin-dependent non-image-forming effect.
  • Circadian Contrasts in Heart Rate Variability Associated With Posttraumatic Stress Disorder Symptoms in a Young Adult Cohort, Michelle B. Rissling, Paul A. Dennis, Lana L. Watkins, Patrick S. Calhoun, Michelle F. Dennis, Jean C. Beckham, Junichiro Hayano, Christi S. Ulmer, JOURNAL OF TRAUMATIC STRESS, 29, (5) 415 - 421,   2016年10月, 査読有り, Prior research has demonstrated that individuals exposed to trauma have shown impaired autonomic function. We sought to determine if heart rate variability (HRV), a marker of impaired autonomic function, differed across periods of wake, rest, and sleep as a function of the level of symptoms of posttraumatic stress disorder (PTSD). A sample of young adults (N = 209), 95 of whom met full criteria for current PTSD based on the Clinician Administered PTSD Scale (CAPS; Blake etal., 1995), were evaluated for approximate to 24 hr using actigraphy and electrocardiogram. Actigraphy data were categorized as active, rest, or sleep. Multilevel modeling analyses showed that individuals with high PTSD symptom severity had lower high-frequency HRV than individuals with low PTSD symptom severity during periods of sleep, t(1083) = 2.20, p = .028, Cohen's d = 0.12. No differences were found during periods of activity, t(1083) = 1.34, p = .499, d = 0.05, or rest, t(1083) = 1.34, p = .180, d = 0.09. Our findings extended the import of prior studies to suggest that those with elevated PTSD symptoms may have decreased parasympathetic control during sleep. Moreover, relative to periods of wake and rest, sleep may represent a state of increased vulnerability for decreased parasympathetic cardiac control. Individuals with elevated PTSD symptoms may benefit from early screening for detection of cardiovascular disease.
  • Exploring the relation between heart rate variability characteristics and sympathetic nervous system activity, Ken Kiyono, Junichiro Hayano, Yoshiharu Yamamoto, Anesthesia and Resuscitation, 52, 103 - 108,   2016年09月01日, Heart rate variability (HRV) analysis has been widely used as a noninvasive assessment tool for autonomic nervous system function, and it has been shown that reduced and/or abnormal HRV is associated with an increased risk of mortality in cardiac patients. However, in the analysis of long-term HRV, it has become to be recognized that most HRV indices primarily reflect vagal function and that there is no established HRV-based index for evaluating sympathetic nervous system activity. This paper reviews the relation between conventional HRV indices and autonomic nervous system function. In addition, we introduce a non-Gaussianity index that have recently been proposed as a potential marker of sympathetic overactivity.
  • Examining the Crux of Autonomic Dysfunction in Posttraumatic Stress Disorder: Whether Chronic or Situational Distress Underlies Elevated Heart Rate and Attenuated Heart Rate Variability, Paul A. Dennis, Eric A. Dedert, Elizabeth E. Van Voorhees, Lana L. Watkins, Junichiro Hayano, Patrick S. Calhoun, Andrew Sherwood, Michelle F. Dennis, Jean C. Beckham, PSYCHOSOMATIC MEDICINE, 78, (7) 805 - 809,   2016年09月, 査読有り, Objective Posttraumatic stress disorder (PTSD) has been linked to elevated heart rate (HR) and reduced heart rate variability (HRV) in cross-sectional research. Using ecological momentary assessment and minute-to-minute HRV/HR monitoring, we examined whether cross-sectional associations between PTSD symptom severity and HRV/HR were due to overall elevations in distress levels or to attenuated autonomic regulation during episodes of acute distress. Methods Two hundred nineteen young adults (18-39 years old), 99 with PTSD, underwent 1 day of Holter monitoring and concurrently reported distress levels via ecological momentary assessment. Using multilevel modeling, we examined the associations between momentary distress and the 5-minute means for low-frequency (LF) and high-frequency (HF) HRV and HR immediately following distress ratings, and whether PTSD symptom severity moderated these associations. Results Compared with the controls, participants with PTSD recorded higher ambulatory distress (mean [standard deviation] = 1.7 [0.5] versus 1.2 [0.3], p < .001) and HR (87.2 [11.8] versus 82.9 [12.6] beats/min, p = .011), and lower ambulatory LF HRV (36.9 [14.7] versus 43.7 [16.9 ms, p = .002) and HF HRV (22.6 [12.3] versus 26.4 [14.6] milliseconds, p = .043). Overall distress level was not predictive of HR or HRV (p values > .27). However, baseline PTSD symptom severity was associated with elevated HR (t(1257) = 2.76, p = .006) and attenuated LF (t(1257) = -3.86, p < .001) and HF (t(1257) = -2.62, p = .009) in response to acute momentary distress. Conclusions Results suggest that PTSD is associated with heightened arousal after situational distress and could explain prior findings associating PTSD with HR/HRV. Implications for treatment and cardiovascular risk are discussed.
  • L/T-type calcium channel blocker reduces non-Gaussianity of heart rate variability in chronic kidney disease patients under preceding treatment with ARB, Michio Fukuda, Yoshiaki Ogiyama, Ryo Sato, Toshiyuki Miura, Hidekatsu Fukuta, Masashi Mizuno, Ken Kiyono, Yoshiharu Yamamoto, Junichiro Hayano, Nobuyuki Ohte, JOURNAL OF THE RENIN-ANGIOTENSIN-ALDOSTERONE SYSTEM, 17, (2) ,   2016年04月, 査読有り, Introduction: Increased sympathetic nerve activity has been suggested in patients with chronic kidney disease (CKD). Pathologic sympathetic activity can alter heart rate variability (HRV), and the altered HRV has prognostic importance, so that reducing sympathetic activity may be an important strategy. Novel nonlinear HRVs, including deceleration capacity (DC), have greater predictive power for mortality. We have recently proposed an increase in a non-Gaussianity index of HRV, lambda(25s), which indicates the probability of volcanic heart rate deviations of departure from each standard deviation level, as a marker of sympathetic cardiac overdrive. L/T-type calcium channel blocker (L/T-CCB), azelnidipine, decreases sympathetic nerve activity in experimental and clinical studies. Methods: In 43 hypertensive patients with CKD under treatment with an angiotensin receptor blocker (ARB), we investigated whether 8-week add-on L/T-CCB treatment could restore HRV. Results: Means of all normal-to-normal intervals over 24 h (p<0.0001) and DC (p=0.002) increased, and lambda(25s) (p=0.001) decreased regardless of gender, age, renal function or blood pressure, while no significant changes were observed in the other HRVs. Conclusions: Reduction of lambda(25s) is useful to assess the effect of sympathoinhibitory treatment. Further studies are needed to investigate if the restoration of HRV is directly associated with the improvement of prognosis in patients with CKD.
  • Autonomic nervous responses in colorectal polypectomy: Randomized controlled trial comparing air and carbon dioxide insufflation, Kenji Murakami, Hiromi Kataoka, Junichiro Hayano, Hidekatsu Fukuta, Yoshinori Mori, Hirotaka Nishiwaki, Tsutomu Mizoshita, Mamoru Tanaka, Yasuyuki Okamoto, Takaya Shimura, Yoshikazu Hirata, Takashi Mizushima, Masahide Ebi, Takashi Joh, DIGESTIVE ENDOSCOPY, 28, (2) 203 - 209,   2016年03月, 査読有り, Background and AimCarbon dioxide (CO2) insufflation devices are commonly used for endoscopic examination and treatment. In this prospective randomized controlled trial (RCT), we compared patient acceptance, cardiovascular tolerance, and autonomic nervous responses between patients receiving air insufflation and CO2 insufflation. MethodsWe initially enrolled 170 patients and, of these, 158 patients in total were analyzed (air group, 83; CO2 group, 75). Autonomic nervous responses were evaluated by analysis of heart rate variability (HRV). Primary end point was superiority in the effects of CO2 insufflation on the autonomic nervous system by HRV analysis. ResultsVisual analog scale disclosed significantly less abdominal pain and abdominal fullness with CO2. Percentage heart rate change rate at 1h and 4h after the procedure was also significantly lower in the CO2 group than in the air group (1h after: P < 0.01, 4h after: P < 0.05). Comparison based on age showed that % heart rate change was significantly lower in the younger CO2 patients (just after colonoscopy and 1h after: P < 0.01, 4h after: P < 0.05), but this difference was not apparent in an older group of patients. ConclusionsThis is the first RCT showing that colorectal polypectomy using CO2 insufflation significantly decreases abdominal pain and abdominal fullness common in such patients with lowered stress to the autonomous nervous system. The effects using CO2 insufflation on the sympathetic nervous system also seemed to be more prominent among younger patients.
  • Exploring the relationship between posttraumatic stress disorder symptoms and momentary heart rate variability, Kimberly T. Green, Paul A. Dennis, Lydia C. Neal, Andrea L. Hobkirk, Terrell A. Hicks, Lana L. Watkins, Junichiro Hayano, Andrew Sherwood, Patrick S. Calhoun, Jean C. Beckham, JOURNAL OF PSYCHOSOMATIC RESEARCH, 82, 31 - 34,   2016年03月, 査読有り, Objective: Exposure to trauma-related cues has been associated with a prolonged decrease in heart rate variability (HRV) under laboratory conditions, however the relationship between PTSD symptoms and HRV has not been evaluated during everyday life. The present study sought to determine whether Posttraumatic Stress Disorder (PTSD) symptoms reported during everyday life were related to reduced HRV. Methodology: Eighty-three young adults with PTSD underwent 24-hour Holter monitoring, during which PTSD symptoms were measured using ecological momentary assessment (EMA). Multilevel modeling was used to examine the association between PTSD symptom severity and low frequency (LF) and high frequency (HF) HRV. Results: PTSD symptoms were associated with reductions in LF HRV, independently of age and activity level. There was no significant association between PTSD symptom levels and HF HRV. Conclusions: These results indicate that an association between momentary PTSD symptom severity and reduced LF HRV is significant and observable in young adults with PTSD. Findings highlight the need for cardiovascular screening in young adults with PTSD and early interventions that target physiological reactivity in PTSD. (C) 2016 Elsevier Inc. All rights reserved.
  • Association Between Regional Difference in Heart Rate Variability and Inter-prefecture Ranking of Healthy Life Expectancy: ALLSTAR Big Data Project in Japan., Emi Yuda, Yuki Furukawa, Yutaka Yoshida, Junichiro Hayano, Lecture Notes of the Institute for Computer Sciences, Social-Informatics and Telecommunications Engineering, LNICST, 194 LNICST, 23 - 28,   2016年, © ICST Institute for Computer Sciences, Social Informatics and Telecommunications Engineering 2017. As a physiological big-data project named ALLSTAR, we have developed a 24-hr ambulatory electrocardiogram database of 81,615 males and 103,038 females (≥20 yr) from all over Japan. With this database, we examined if regional differences in heart rate (HR) and HR variability (HRV) are associated with the inter-prefecture rankings of healthy life expectancy (HALE) and of average life expectancy (ALE) in Japan. According to reports by the Japanese Ministry of Health, Labour and Welfare (2013), subjects in each sex were grouped into short, middle, and long HALE and ALE tertiles by their living prefectures. Standard deviation of 24-h normal-to-normal R-R intervals (SDNN) increased progressively with increasing HALE tertiles in both sexes (Ps < 0.001), while it showed no consistent associations with ALE. Conversely, HR decreased progressively with increasing ALE tertiles in females (P < 0.001), while it showed no consistent association with HALE. These suggest HRV may reflect a biological property relating to long HALE.
  • Physical and Psychophysiological Impacts of GPS Labor Management in Nursing Home Workers., Emi Yuda, Yutaka Yoshida, Kazuo Mizuno, Harushi Urushihara, Junichiro Hayano, Proceedings of the 13th International Conference on Mobile and Ubiquitous Systems: Computing, Networking and Services, MobiQuitous 2016, Hiroshima, Japan, November 28 - December 1, 2016, 294 - 294,   2016年, 査読有り
  • Longer lying position causes lower LF/HF of heart rate variability during ambulatory monitoring., Yutaka Yoshida, Yuki Furukawa, Hiroki Ogasawara, Emi Yuda, Junichiro Hayano, IEEE 5th Global Conference on Consumer Electronics, GCCE 2016, Kyoto, Japan, October 11-14, 2016, 1 - 2,   2016年, 査読有り
  • Beat-to-beat T-wave amplitude variability in the risk stratification of right ventricular outflow tract-premature ventricular complex patients, Tomohide Ichikawa, Yoshihiro Sobue, Atsunobu Kasai, Ken Kiyono, Junichiro Hayano, Mayumi Yamamoto, Kentarou Okuda, Eiichi Watanabe, Yukio Ozaki, EUROPACE, 18, (1) 138 - 145,   2016年01月, 査読有り, Premature ventricular complexes (PVCs) originating from the right ventricular outflow tract (RVOT) may occasionally trigger monomorphic ventricular tachycardia (MVT), polymorphic ventricular tachycardia (PVT), or ventricular fibrillation (VF). We examined whether an analysis of the ventricular repolarization instability could differentiate PVT/VF triggered by RVOT-PVCs from benign RVOT-PVCs or MVT. We evaluated the ventricular repolarization instability as assessed by the beat-to-beat T-wave amplitude variability (TAV) using Holter recordings in patients with RVOT-PVCs but with no structural heart disease. We determined the prematurity index, defined as the ratio of the coupling interval of the first ventricular tachycardia (VT) beat or isolated PVC to the preceding R-R interval just before the VT or isolated PVC in the Holter recordings. The study patients were classified into RVOT-PVCs/MVT (n = 33) and PVT/VF (n = 10). The two groups did not differ with respect to the age, sex, and left ventricular ejection fraction. There was no significant difference in the prematurity index between the two groups (RVOT-PVCs/MVT 0.66 +/- 0.16 vs. PVT/VF 0.61 +/- 0.13, P = 0.60). The patients with PVT/VF had a significantly larger maximum TAV than those with RVOT-PVCs/MVT (31 +/- 13 vs. 68 +/- 40 A mu V, P < 0.001). Patients with a higher than median value of the TAV (33 A mu V) were at increased risk of PVT/VF vs. those with a lower than median value, after adjusting for the age and sex [9.25 (95% confidence interval: 1.27-19.2); P = 0.03]. The TAV analysis is a useful measure to identify the subset of usually benign RVOT-PVC/MVT patients prone to PVT/VF.
  • Long-range correlations in amplitude variability of HF and LF components of Heart Rate Variability, Yuki Miki, Yasuyuki Suzuki, Eiichi Watanabe, Junichiro Hayano, Yoshiharu Yamamoto, Taishin Nomura, Ken Kiyono, 2016 38TH ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY (EMBC), 2016, (EMBC) 6218 - 6221,   2016年, 査読有り, For the assessment of autonomic nervous system activity based on heart rate variability (HRV) analysis, characteristics of high-frequency (HF; 0.15 to 0.4 Hz) and low-frequency (LF; 0.04 to 0.15 Hz) components have been widely employed. HF and LF band powers quantified by power spectral analysis have most commonly been used in the conventional studies; the physiological significance of these measures has also been extensively studied. However, nonlinear characteristics of HF and LF components have not been well established. In this paper, we investigated nonlinear properties of HF and LF components in 122 healthy subjects and 108 patients with congestive heart failure (CHF). By analyzing bandpass-filtered time series of HRV corresponding to HF and LF components, it is shown that amplitude variability of HF and LF components displays long-range correlation, which cannot be explained by linear HRV properties. Compared with the age-matched healthy control group, the CHF patients showed significantly decreased long range correlation of HF component amplitude variability. These findings suggest that nonlinear properties of HF and LF components provides some complementary information on HRV dynamics.
  • Multiscale Entropy of the Heart Rate Variability for the Prediction of an Ischemic Stroke in Patients with Permanent Atrial Fibrillation, Eiichi Watanabe, Ken Kiyono, Junichiro Hayano, Yoshiharu Yamamoto, Joji Inamasu, Mayumi Yamamoto, Tomohide Ichikawa, Yoshihiro Sobue, Masehide Harada, Yukio Ozaki, PLOS ONE, 10, (9) ,   2015年09月, 査読有り, Background Atrial fibrillation (AF) is a significant risk factor for ischemic strokes, and making a robust risk stratification scheme would be important. Few studies have examined whether nonlinear dynamics of the heart rate could predict ischemic strokes in AF. We examined whether a novel complexity measurement of the heart rate variability called multiscale entropy (MSE) was a useful risk stratification measure of ischemic strokes in patients with permanent AF. Methods and Results We examined 173 consecutive patients (age 69 +/- 11 years) with permanent AF who underwent 24-hour Holter electrocardiography from April 2005 to December 2006. We assessed several frequency ranges of the MSE and CHA(2)DS(2)-VASc score (1 point for congestive heart failure, hypertension, diabetes, vascular disease, an age 65 to 74 years, and a female sex and 2 points for an age >= 75 years and a stroke or transient ischemic attack). We found 22 (13%) incident ischemic strokes during a mean follow up of 3.8-years. The average value of the MSE in the very-low frequency subrange (90-300 s, MeanEn(VLF2)) was significantly higher in patients who developed ischemic strokes than in those who did not (0.68 +/- 0.15 vs. 0.60 +/- 0.14, P<0.01). There was no significant difference in the C-statistic between the CHA(2)DS(2)-VASc score and MeanEn(VLF2) (0.56; 95% confidence interval, 0.43-0.69 vs. 0.66; 95% confidence interval, 0.53-0.79). After an adjustment for the age, CHA(2)DS(2)-VASc score, and antithrombotic agent, a Cox hazard regression model revealed that the MeanEn(VLF2) was an independent predictor of an ischemic stroke (hazard ratio per 1-SD increment, 1.80; 95% confidence interval, 1.17-2.07, P<0.01). Conclusion The MeanEn(VLF2) in 24-hour Holter electrocardiography is a useful risk stratification measure of ischemic strokes during the long-term follow-up in patients with permanent AF.
  • Relaxation enhances respiratory sinus arrhythmia, a cardiorespiratory resting function, Masahito Sakakibara, Masahito Sakakibara, Junichiro Hayano, Junichiro Hayano, Heart Rate Variability (HRV): Prognostic Significance, Risk Factors and Clinical Applications, 149 - 163,   2015年01月01日, © 2015 by Nova Science Publishers, Inc. All rights reserved. Reduced heart rate variability (HRV) is associated with physical and mental stresses. Several studies have shown that relaxation techniques enhance respiratory sinus arrhythmia (RSA), which can be measured quantitatively as a high-frequency component of HRV. Although RSA is mediated by the respiratory modulation of cardiac vagal outflow and its magnitude has been used as an index of cardiac vagal activity, RSA itself is thought to be an intrinsic cardiorespiratory resting function (Hayano & Yasuma, 2003). When the breathing rate reduced, the presence of RSA improves pulmonary gas exchange efficiency by matching alveolar ventilation and capillary perfusion throughout the respiration cycle. The activation of RSA in cooperation with tonic vagal heart rate control selectively suppresses unnecessary heart beats, and effectively saves cardiorespiratory energy expenditure at rest. RSA increases during sleep and it is also activated according to the level of cardiopulmonary functional reserve at rest. Thus, RSA functions as an endogenous marker, which reflects the cardiorespiratory resting function. Recent studies have demonstrated that real-world stress decreases the magnitude of high-frequency component of HRV during sleep, whereas relaxation training increases the high- frequency component during sleep, suggesting that relaxation training may improve the cardiorespiratory resting function. Also, a number of studies have demonstrated that HRV biofeedback, an intervention aimed at increasing HRV, has clinical utility in the treatment of a variety of physical and mental disorders that involve autonomic nervous system dysrégulation. Further study would be worthwhile to examine whether relaxation training in real-life situations might enhance the cardiorespiratory resting function through increasing HRV, and help ameliorate psychophysiologic symptoms in clinical population.
  • Psychosocial factors are preventive against coronary events in Japanese men with coronary artery disease: The Eastern Collaborative Group Study 7.7-year follow-up experience, Reiko Hori, Jun-ichiro Hayano, Kazuhiro Kimura, Nitaro Shibata, Fumio Kobayashi, BIOPSYCHOSOCIAL MEDICINE, 9, (1) ,   2015年01月, 査読有り, Background: The Japanese Coronary-prone Behaviour Scale (JCBS) is a questionnaire developed by the Eastern Collaborative Group Study (ECGS), a multi-centre study of coronary-prone behaviour among Japanese men. Subscale C of the JCBS consists of 9 items that have been independently associated with the presence of coronary artery disease (CAD) in patients undergoing coronary angiography (CAG). There have been no reports of a relationship between any behavioural factor and the prognosis of CAD in Japan. The purpose of the current study was to investigate behavioural correlations with the prognosis of CAD as a part of the ECGS. Methods: We examined the mortality and coronary events of 201 men (58 +/- 10, 27-86 years) enrolled in the ECGS from 1990 to 1995, who underwent diagnostic coronary angiography and were administered the JCBS and the Japanese version of the Jenkins Activity Survey (JAS) Form C. Their health information after CAG was determined by a review of their medical records and by telephone interviews that took place from 2002 to 2003. Results: Cardiac events during the follow-up period (7.7 +/- 4.2 years) included 13 deaths from CAD, 25 cases of new-onset myocardial infarction, 26 cases of percutaneous coronary intervention, and 19 cases of coronary artery bypass graft surgery. There was no difference in established risk factors between groups with and without cardiac events. Seven factors were extracted by principal component analysis in order to clarify which factors were measured by the JCBS. Stepwise multivariate Cox-hazard regression analysis, in which 9 standard coronary risk factors were forced into the model, showed that Factor 4 from the JCBS (namely, the Japanese spirit of 'Wa') was independently associated with coronary events (hazard ratio: 0.21; p = 0.01). By other Cox-hazards regression analyses of coronary events using each set of JAS scores and the JCBS Scale C score instead of Factor 4 as selectable variables, the JAS scores or the JCBS Scale C score were not entered into the models. Conclusion: The Japanese spirit of 'Wa' is a preventive factor against coronary events for Japanese men with CAD.
  • Point-Process High-Resolution Representations of Heartbeat Dynamics for Multiscale Analysis: a CHF Survivor Prediction Study, G. Valenza, H. Wendt, K. Kiyono, J. Hayano, E. Watanabe, Y. Yamamoto, P. Abry, R. Barbieri, 2015 37TH ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY (EMBC), 2015-November, 1951 - 1954,   2015年, 査読有り, Multiscale analysis of human heartbeat dynamics has been proved effective in characterizeing cardiovascular control physiology in health and disease. However, estimation of multiscale properties can be affected by the interpolation procedure used to preprocess the unevenly sampled R-R intervals derived from the ECG. To this extent, in this study we propose the estimation of wavelet coefficients and wavelet leaders on the output of inhomogeneous point process models of heartbeat dynamics. The RR interval series is modeled using probability density functions (pdfs) characterizing and predicting the time until the next heartbeat event occurs, as a linear function of the past history. Multiscale analysis is then applied to the pdfs' instantaneous first order moment. The proposed approach is tested on experimental data gathered from 57 congestive heart failure (CHF) patients by evaluating the recognition accuracy in predicting survivor and non-survivor patients, and by comparing performances from the informative point-process based interpolation and non-informative spline-based interpolation. Results demonstrate that multiscale analysis of point-process high-resolution representations achieves the highest prediction accuracy of 65.45%, proving our method as a promising tool to assess risk prediction in CHF patients.
  • Nocturnal patterns of heart rate and the risk of mortality after acute myocardial infarction, Robert M. Carney, Brian Steinmeyer, Kenneth E. Freedland, Phyllis K. Stein, Junichiro Hayano, James A. Blumenthal, Allan S. Jaffe, AMERICAN HEART JOURNAL, 168, (1) 117 - 125,   2014年07月, 査読有り, Background The purposes of this study were to identify nocturnal patterns of heart rate (HR) in depressed and noridepressed patients after an acute myocardial infarction (MI) and to determine which patterns, if any, are associated with all-cause mortality or recurrent infarction. Methods Functional data analysis and model-based clustering methods were used to identify nocturnal HR patterns in 245 depressed and 247 nondepressed patients with a recent MI. All-cause mortality and recurrent infarctions were ascertained over a median follow-up of 24 months. Results Three HR activity patterns were identified. In the first, HR gradually declined during the nighttime and increased the next morning. The second pattern was similar, but with a higher overall HR during the recording interval. The third showed almost no decrease in HR at night (ie, "nondipping"). All-cause mortality was higher among patients with pattern 3 than pattern 1 (P = .007), and the combined end point of recurrent MI or all-cause mortality was higher in pattern 3 than pattern 2 (P = .05). Patterns 2 and 3 were more common in the depressed than in the nondepressed patients. Conclusions The nondipping nocturnal HR independently predicts all-cause mortality and recurrent MI. Future studies should examine the underlying causes of nondipping nocturnal HR and its association with depression and investigate the effects of treatment on survival.
  • MultiScale Wavelet p-Leader based Heart Rate Variability Analysis for Survival Probability Assessment in CHF Patients, H. Wendt, K. Kiyono, P. Abry, J. Hayano, E. Watanabe, Y. Yamamoto, 2014 36TH ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY (EMBC), 2014, 2809 - 2812,   2014年, 査読有り, A priori discrimination of high mortality risk amongst congestive heart failure patients constitutes an important clinical stake in cardiology and involves challenging analyses of the temporal dynamics of heart rate variability (HRV). The present contribution investigates the potential of a new multifractal formalism, constructed on wavelet p-leader coefficients, to help discrimination between survivor and non survivor patients. The formalism, applied to a high quality database of 108 patients collected in a Japanese hospital, enables to assess the existence of multifractal properties amongst congestive heart failure patients and to reveal significant differences in the multiscale properties of HRV between survivor and non survivor patients, for scales ranging from approximately 60 to 250 beats.
  • Site-specific organ-selective effect of epifascial acupuncture on cardiac and gastric autonomic functions., Minagawa M, Kurono Y, Ishigami T, Yamada A, Kakamu T, Akai R, Hayano J, Autonomic neuroscience : basic & clinical, 179, (1-2) 151 - 154,   2013年12月, 査読有り
  • Heart Rate Variability Biofeedback Improves Cardiorespiratory Resting Function During Sleep, Masahito Sakakibara, Junichiro Hayano, Leo O. Oikawa, Maria Katsamanis, Paul Lehrer, APPLIED PSYCHOPHYSIOLOGY AND BIOFEEDBACK, 38, (4) 265 - 271,   2013年12月, 査読有り, The present study was designed to examine the effect of heart rate variability (HRV) biofeedback on the cardiorespiratory resting function during sleep in daily life. Forty-five healthy young adults were randomly assigned to one of three groups: HRV biofeedback, Autogenic Training (AT), and no-treatment control. Participants in the HRV biofeedback were instructed to use a handheld HRV biofeedback device before their habitual bedtime, those in the AT were asked to listen to an audiotaped instruction before bedtime, and those in the control were asked to engage in their habitual activity before bedtime. Pulse wave signal during sleep at their own residences was measured continuously with a wristwatch-type transdermal photoelectric sensor for three time points. Baseline data were collected on the first night of measurements, followed by two successive nights for HRV biofeedback, AT, or control. Cardiorespiratory resting function was assessed quantitatively as the amplitude of high-frequency (HF) component of pulse rate variability, a surrogate measure of respiratory sinus arrhythmia. HF component increased during sleep in the HRV biofeedback group, although it remained unchanged in the AT and control groups. These results suggest that HRV biofeedback before sleep may improve cardiorespiratory resting function during sleep.
  • Analogy of entrainment (respiratory modulation) of heartbeats in cheyne-stokes respiration in heart failure and respiratory sinus arrhythmia: Its physiological significance, Fumihiko Yasuma, Tamotsu Tanahashi, Jun Ichiro Hayano, Yuuki Shimizu, Toyoaki Murohara, Respiration and Circulation, 61, 944 - 950,   2013年10月01日
  • Central sleep apnoea and inflammation are independently associated with arrhythmia in patients with heart failure., Kan Sano, Eiichi Watanabe, Junichiro Hayano, Yuuki Mieno, Yoshihiro Sobue, Mayumi Yamamoto, Tomohide Ichikawa, Hiroki Sakakibara, Kazuyoshi Imaizumi, Yukio Ozaki, European journal of heart failure, 15, (9) 1003 - 10,   2013年09月, 査読有り, AIMS: We examined whether the severity of central sleep apnoea (CSA) and the level of C-reactive protein are associated with the prevalence and complexity of arrhythmias, and whether these factors contribute to increased risk of nocturnal sudden death. METHODS AND RESULTS: We prospectively examined 178 patients (age 70 ± 1 years) who were admitted to our hospital due to worsening heart failure. We recorded a simultaneous overnight cardiorespiratory polygraph and Holter ECG. Obstructive sleep apnoea was excluded and patients were dichotomized based on the median value of the central apnoea index (CAI) of 7.5/h. The prevalence and complexity of arrhythmias were compared between daytime (06:00 h to 15:00 h) and night-time (21:00 h to 06:00 h). A multivariate logistic regression analysis revealed that the CAI was associated with prevalence of atrial fibrillation (AF) [odds ratio 1.03, 95% confidence interval (CI) 1.02-2.51)] and sinus pause during the night-time period (1.12, 95% CI 1.08-1.35). The CAI and C-reactive protein were independently associated with non-sustained ventricular tachycardia during both daytime (1.22, 95% CI 1.00-6.92; and 5.82, 2.58-56.1, respectively) and night-time periods (3.57, 95% CI 1.06-13.1; and 10.7, 3.30-44.4, respectively). During a mean follow-up period of 22 months, 30 (17%) patients had cardiovascular deaths and the CSA was an independent predictor (hazard ratio 1.29, 95% CI 1.16-2.32); only 5 (2.8%) of them died due to ventricular tachyarrhythmia, occurring during wakefulness. CONCLUSIONS: We demonstrated that the severity of CSA and C-reactive protein levels are independently associated with the prevalence and complexity of arrhythmias. CSA was associated with increased mortality risk, but it was not related directly to nocturnal death due to ventricular tachyarrhythmia.
  • Accuracy of ECG-based screening for sleep-disordered breathing: a survey of all male workers in a transport company, Junichiro Hayano, Teruomi Tsukahara, Eiichi Watanabe, Fumihiko Sasaki, Kiyohiro Kawai, Hiroki Sakakibara, Itsuo Kodama, Tetsuo Nomiyama, Keisaku Fujimoto, SLEEP AND BREATHING, 17, (1) 243 - 251,   2013年03月, 査読有り, Sleep-disordered breathing (SDB) is associated with increased risk for cardiovascular morbidity and mortality and for sleepiness-related accidents, but > 75 % of the patients remain undiagnosed. We sought to determine the diagnostic accuracy of ECG-based detection of SDB when used for population-based screening. All male workers, mostly truck drivers, of a transport company (n = 165; age, 43 +/- 12 years) underwent standard attended overnight polysomnography. Cyclic variation of heart rate (CVHR), a characteristic pattern of heart rate associated with SDB, was detected from single-lead ECG signals during the polysomnography by a newly developed automated algorithm of autocorrelated wave detection with adaptive threshold (ACAT). Among 165 subjects, the apnea-hypopnea index (AHI) was a parts per thousand yen5 in 62 (38 %), a parts per thousand yen15 in 26 (16 %), and a parts per thousand yen30 in 16 (10 %). The number of CVHR per hour (CVHR index) closely correlated with AHI [r = 0.868 (95 % CI, 0.825-0.901)]. The areas under the receiver operating characteristic curves for detecting subjects with AHI a parts per thousand yen5, a parts per thousand yen15, and a parts per thousand yen30 were 0.796 (95 % CI, 0.727-0.855), 0.974 (0.937-0.993), and 0.997 (0.971-0.999), respectively. With a predetermined criterion of CVHR index a parts per thousand yen15, subjects with AHI a parts per thousand yen15 were identified with 88 % sensitivity and 97 % specificity (likelihood ratios for positive and negative test, 30.7 and 0.12). The classification performance was retained in subgroups of subjects with obesity, hypertension, diabetes mellitus, dyslipidemia, and decreased autonomic function. The CVHR obtained by the ACAT algorithm may provide a useful marker for screening for moderate-to-severe SDB among apparently healthy male workers.
  • Multi-scale heart rate dynamics detected by phase-rectified signal averaging predicts mortality after acute myocardial infarction, Masaya Kisohara, Phyllis K. Stein, Yutaka Yoshida, Mari Suzuki, Narushi Iizuka, Robert M. Carney, Lana L. Watkins, Kenneth E. Freedland, James A. Blumenthal, Junichiro Hayano, EUROPACE, 15, (3) 437 - 443,   2013年03月, 査読有り, Aims Acceleration and deceleration capacity (AC and DC) for beat-to-beat short-term heart rate dynamics are powerful predictors of mortality after acute myocardial infarction (AMI). We examined if AC and DC for minute-order long-term heart rate dynamics also have independent predictive value. Methods and results We studied 24-hr Hotter electrcardiograms in 708 post-AMI patients who were followed up for up to 30 months thereafter. Acceleration capacity and DC was calculated with the time scales of T (window size defining heart rate) and s (wavelet scale) from 1 to 500 s and compared their prognostic values with conventional measures (AC(conv) and DCconv) that were calculated with (T,s) = [1,2 (beat)]. During the follow-up, 47 patients died. Both increased AC(conv) and decreased DCconv predicted mortality (C statistic, 0.792 and 0.797). Concordantly, sharp peaks of C statistics were observed at (T,s) = [2,7 (sec)] for both increased AC and decreased DC (0.762 and 0.768), but there were larger peaks of C statistics at around [30,60 (sec)] for both (0.783 and 0.796). The C statistic was greater for DC than AC at (30,60) (P = 0.0012). Deceleration capacity at (30,60) was a significant predictor even after adjusted for AC(conv) (P = 0.020) and DCconv (P = 0.028), but the predictive power of AC at (30,60) was no longer significant. Conclusion A decrease in DC for minute-order long-term heart rate dynamics is a strong predictor for post-AMI mortality and the predictive power is independent of AC(conv) and DCconv for beat-to-beat short-term heart rate dynamics.
  • Assessment of Sympathetic Over Activity by the Analysis of Nonlinear Heart Rate Dynamics, Junichiro Hayano, JOURNAL OF PHYSIOLOGICAL SCIENCES, 63, S87 - S87,   2013年, 査読有り
  • Interactive Associations of Depression and Sleep Apnea With Adverse Clinical Outcomes After Acute Myocardial Infarction, Junichiro Hayano, Robert M. Carney, Eiichi Watanabe, Kiyohiro Kawai, Itsuo Kodama, Phyllis K. Stein, Lana L. Watkins, Kenneth E. Freedland, James A. Blumenthal, PSYCHOSOMATIC MEDICINE, 74, (8) 832 - 839,   2012年10月, 査読有り, Objective: Depression and sleep apnea (SA) are common among patients with a recent acute myocardial infarction (AMI), and both are associated with increased risk for adverse outcomes. We tested the hypothesis that there is an interaction between them in relation to post-AMI prognosis. Methods: Participants were patients with a recent AMI, 337 of them were depressed and 379 were nondepressed, who participated in a substudy of the Enhancing Recovery in Coronary Heart Disease (ENRICHD) clinical trial. SA was identified from Hotter electrocardiogram by an algorithm that detects cyclic variation of heart rate. Results: During a median follow-up of 25 months, 83 (11.6%) patients either died or experienced a recurrent AMI and 43 (6.0%) patients died. Among 94 patients with both depression and SA, these end points occurred in 25 (26.6%) and 20 (21.3%) at 3.9- and 6.9-times higher prevalence than predicted probabilities by ENRICHD clinical risk scores (p < .001 for both). In the patients with depression alone, SA alone, or neither, the prevalence was similar to the predicted probability. Depression and SA showed significant interactions in prediction of these end points (p = .02 and p = .03). SA independently predicted these end points in patients with depression (p = .001 and p < .001) but not in those without depression (p = .84 and p = .73). Similarly, depression independently predicted these end points in patients with SA (p < .001 for both) but not in those without SA (p = .12 and p = .61). Conclusions: Depression and SA are interactively associated with adverse clinical outcomes after AMI. Trial Registration: clinicaltrials.gov Identifier: NCT00313573.
  • Nonlinear Measures of Heart Rate Variability and Mortality Risk in Hemodialysis Patients, Mari Suzuki, Takahashi Hiroshi, Toru Aoyama, Miho Tanaka, Hideki Ishii, Masaya Kisohara, Narushi Iizuka, Toyoaki Murohara, Junichiro Hayano, CLINICAL JOURNAL OF THE AMERICAN SOCIETY OF NEPHROLOGY, 7, (9) 1454 - 1460,   2012年09月, 査読有り, Background and objectives Nonlinear measures of heart rate variability (HRV) have gained recent interest as powerful risk predictors in various clinical settings. This study examined whether they improve risk stratification in hemodialysis patients. Design, setting, participants, & measurements To assess heart rate turbulence, deceleration capacity, fractal scaling exponent (alpha(1)), and other conventional HRV measures, 281 hemodialysis patients underwent 24-hour electrocardiography between January 2002 and May 2004 and were subsequently followed up. Results During a median 87-month follow-up, 77 patients (27%) died. Age, left ventricular ejection fraction, serum albumin, C-reactive protein, and calcium X phosphate independently predicted mortality. Whereas all nonlinear HRV measures predicted mortality, only decreased scaling exponent alpha(1) remained significant after adjusting for clinical risk factors (hazard ratio per a 0.25 decrement, 1.46; 95% confidence interval [95% CI], 1.16-1.85). The inclusion of alpha(1) into a prediction model composed of clinical risk factors increased the C statistic from 0.84 to 0.87 (P=0.03), with 50.8% (95% CI, 20.2-83.7) continuous net reclassification improvement for 5-year mortality. The predictive power of a1 showed an interaction with age (P=0.02) and was particularly strong in patients aged <70 years (n=208; hazard ratio, 1.87; 95% CI, 1.38-2.53), among whom alpha(1) increased the C statistic from 0.85 to 0.89 (P=0.01), with a 93.1% (95% CI, 59.3-142.0) continuous net reclassification improvement. Conclusions Scaling exponent alpha(1) that reflects fractal organization of short-term HRV improves risk stratification for mortality when added to the prediction model by conventional risk factors in hemodialysis patients, particularly those aged <70 years. Clin J Am Soc Nephrol 7: 1454-1460, 2012. doi: 10.2215/CJN.09430911
  • Cardiac β-adrenergic receptor density and myocardial systolic function in the remote noninfarcted region after prior myocardial infarction with left ventricular remodelling., Ohte N, Narita H, Iida A, Fukuta H, Iizuka N, Hayano J, Kuge Y, Tamaki N, Kimura G, European journal of nuclear medicine and molecular imaging, 39, (8) 1246 - 1253,   2012年08月, 査読有り
  • Effect of obstructive sleep apnea on response to cognitive behavior therapy for depression after an acute myocardial infarction, Kenneth E. Freedland, Robert M. Carney, Junichiro Hayano, Brian C. Steinmeyer, Rebecca L. Reese, Annelieke M. Roest, JOURNAL OF PSYCHOSOMATIC RESEARCH, 72, (4) 276 - 281,   2012年04月, 査読有り, Objective: To determine whether obstructive sleep apnea (OSA) interferes with cognitive behavior therapy (CBT) for depression in patients with coronary heart disease. Methods: Patients who were depressed within 28 days after an acute myocardial infarction (MI) were enrolled in the Enhancing Recovery in Coronary Heart Disease. (ENRICHD) trial; 289 (12%) of the 2481 participants in ENRICHD met the criteria for inclusion in this ancillary study. Results: A validated ambulatory ECG algorithm was used to detect OSA. Of the 289 participants, 64 (22%) met the criteria for OSA. CBT was efficacious relative to usual care (UC) for depression (p=.004). OSA had no effect on 6-month Beck Depression Inventory (BDI) scores (p=.11), and there was no interaction between OSA and treatment (p=.42). However, the adjusted mean (se.) 6-month BDI scores among patients without OSA were 122 (0.8) vs. 9.0 (0.8) in the UC and CBT groups (Cohen's d=.40); among those with OSA, they were 9.5 (1.4) and 8.1 (1.5) in the UC and CBT groups (d=.17). There were no significant OSA x Treatment interactions in the major depression (n = 131) or minor depression (n=158) subgroups, but in those with major depression, there was a larger treatment effect in those without (d=.44) than with (d=.09) OSA. In those with minor depression, the treatment effects were d=.37 and d=.25 for the non-OSA and OSA subgroups. Conclusion: CBT is efficacious for depression after an acute Myocardial infarction in patients without obstructive sleep apnea, but it may be less efficacious for post-MI patients with OSA. (C) 2012 Elsevier Inc. All rights reserved.
  • LONG-TIME-SCALE HEART RATE DYNAMICS DETECTED BY PHASE-RECTIFIED SIGNAL AVERAGING PREDICTS MORTALITY AFTER ACUTE MYOCARDIAL INFARCTION, Masaya Kisohara, Mari Suzuki, Narushi Iizuka, Robert Carney, Phyllis Stein, Lana L. Watkins, Kenneth Freedland, James Blumenthal, Junichiro Hayano, JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY, 59, (13) E1520 - E1520,   2012年03月, 査読有り
  • AUTONOMIC ANTAGONISM UNDERLIES HEART RATE COMPLEXITY, Zbigniew R. Struzik, Ken Kiyono, Junihiro Hayano, Shin Kwak, Yoshiharu Yamamoto, SUMMER SOLSTICE 2011 INTERNATIONAL CONFERENCE ON DISCRETE MODELS OF COMPLEX SYSTEMS, 5, (1) 181 - 190,   2012年, We investigate multiscale properties of intermittency of heart rate variability (HRV) through non-Gaussianity and through two-point one-scale magnitude correlations in HRV of patients with congestive heart failure (CHF) - both survivors (CHF-SV) and non-survivors (CHF-NS) - and of patients with primary autonomic failure (PAF). We confirm the sympathetic origin of the non-Gaussianity index elucidating its random character. We further confirm intermittency of the high frequency, fine scale firing of the parasympathetic nervous system branch, responsible for the multifractal complexity. We obtain further confirmation of the antagonistic function of the autonomic regulation of HRV, this time in terms of intermittency - heteroscedastic clustering of variance. In this context, we identify autonomic antagonism as the source of the mid to low frequency, intermediate scale intermittency observed at higher levels in CHF patients with elevated sympathetic activation and suppressed in the PAF patients - the case of neurogenic SNS dysfunction.
  • Non-Gaussianity of low frequency heart rate variability and sympathetic activation: lack of increases in multiple system atrophy and Parkinson disease, Ken Kiyono, Junichiro Hayano, Shin Kwak, Eiichi Watanabe, Yoshiharu Yamamoto, FRONTIERS IN PHYSIOLOGY, 3,   2012年, 査読有り, The correlates of indices of long-term ambulatory heart rate variability (HRV) of the autonomic nervous system have not been completely understood. In this study, we evaluated conventional HRV indices, obtained from the daytime (12:00-18:00) Holter recording, and a recently proposed non-Gaussianity index (lambda; Kiyono et al., 2008) in 12 patients with multiple system atrophy (MSA) and 10 patients with Parkinson disease (PD), known to have varying degrees of cardiac vagal and sympathetic dysfunction. Compared with the age-matched healthy control group, the MSA patients showed significantly decreased HRV, most probably reflecting impaired vagal heart rate control, but the PD patients did not show such reduced variability. In both MSA and PD patients, the low-to-high frequency (LF/HF) ratio and the short-term fractal exponent alpha(1), suggested to reflect the sympathovagal balance, were significantly decreased, as observed in congestive heart failure (CHF) patients with sympathetic overdrive. In contrast, the analysis of the non-Gaussianity index lambda showed that a marked increase in intermittent and non-Gaussian HRV observed in the CHF patients was not observed in the MSA and PD patients with sympathetic dysfunction. These findings provide additional evidence for the relation between the non-Gaussian intermittency of HRV and increased sympathetic activity.
  • Allostasis: A New Paradigm for Detecting Ultra-Early Signs of Cardiovascular Diseases, Junichiro Hayano, Transactions of Japanese Society for Medical and Biological Engineering, 49, 372 - 374,   2011年12月14日
  • HRV Biofeedback Improves Cardiorespiratory Resting Function During Sleep, Masahito Sakakibara, Junichiro Hayano, Leo Oikawa, Maria Katsamanis, Paul Lehrer, APPLIED PSYCHOPHYSIOLOGY AND BIOFEEDBACK, 36, (3) 225 - 225,   2011年09月, 査読有り
  • Acupuncture to Danzhong but not to Zhongting increases the cardiac vagal component of heart rate variability, Yasuzo Kurono, Munenori Minagawa, Tatsuyo Ishigami, Atsushi Yamada, Toshinori Kakamu, Junichiro Hayano, AUTONOMIC NEUROSCIENCE-BASIC & CLINICAL, 161, (1-2) 116 - 120,   2011年04月, 査読有り, There is currently no convincing evidence that acupuncture has any specific effects on autonomic nervous function as assessed by heart rate variability (HRV). We examined whether the stimulation of neighboring acupunctural points, Danzhong (CV17) and Zhongting (CV16) on the anterior median line of the thorax, induced different effects on HRV. In 14 healthy males, epifascial acupunctural stimulation (single instantaneous needle stimulation on the fascial surface without producing De-Qi sensation) was performed at CV17 and CV16 on different days in a clinical study utilizing a cross-over design. We found that the stimulation of CV17, but not of CV16, decreased the heart rate (P=0.01, repeated measures ANOVA) and increased the power of the high-frequency component of the HRV, an index of cardiac vagal activity (P=0.01). The low-frequency to high-frequency ratio, an index of sympathetic activity showed no significant changes for either point. Our observations could not be explained as either nonspecific or psychological/placebo effects of needle stimulation. This study provides strong evidence for the presence of a specific acupunctural point that causes the modulation of cardiac autonomic function. (C) 2010 Elsevier B.V. All rights reserved.
  • Screening for Obstructive Sleep Apnea by Cyclic Variation of Heart Rate, Junichiro Hayano, Eiichi Watanabe, Yuji Saito, Fumihiko Sasaki, Keisaku Fujimoto, Tetsuo Nomiyama, Kiyohiro Kawai, Itsuo Kodama, Hiroki Sakakibara, CIRCULATION-ARRHYTHMIA AND ELECTROPHYSIOLOGY, 4, (1) 64 - 72,   2011年02月, 査読有り, Background-Despite the adverse cardiovascular consequences of obstructive sleep apnea, the majority of patients remain undiagnosed. To explore an efficient ECG-based screening tool for obstructive sleep apnea, we examined the usefulness of automated detection of cyclic variation of heart rate (CVHR) in a large-scale controlled clinical setting. Methods and Results-We developed an algorithm of autocorrelated wave detection with adaptive threshold (ACAT). The algorithm was optimized with 63 sleep studies in a training cohort, and its performance was confirmed with 70 sleep studies of the Physionet Apnea-ECG database. We then applied the algorithm to ECGs extracted from all-night polysomnograms in 862 consecutive subjects referred for diagnostic sleep study. The number of CVHR per hour (the CVHR index) closely correlated(r=0.84) with the apnea-hypopnea index, although the absolute agreement with the apnea-hypopnea index was modest (the upper and lower limits of agreement, 21 per hour and -19 per hour) with periodic leg movement causing most of the disagreement (P < 0.001). The CVHR index showed a good performance in identifying the patients with an apnea-hypopnea index >= 15 per hour (area under the receiver-operating characteristic curve, 0.913; 83% sensitivity and 88% specificity, with the predetermined cutoff threshold of CVHR index >= 15 per hour). The classification performance was unaffected by older age (>= 65 years) or cardiac autonomic dysfunction (SD of normal-to-normal R-R intervals over the entire length of recording < 65 ms; area under the receiver-operating characteristic curve, 0.915 and 0.911, respectively). Conclusions-The automated detection of CVHR with the ACAT algorithm provides a powerful ECG-based screening tool for moderate-to-severe obstructive sleep apnea, even in older subjects and in those with cardiac autonomic dysfunction. (Circ Arrhythm Electrophysiol. 2011;4:64-72.)
  • Sleep Apnea and Cardiac Arrhythmias, Junichiro Hayano, journal of arrhythmia, 27,   2011年01月01日, Obstructive sleep apnea (OSA) is common among cardiac patients and associated with serious cardiovascular complications, including cardiac arrhythmias and sudden cardiac death. OSA is characterized by repeated obstruction of the upper airway, resulting in intermittent oxygen desaturation during sleep and transient repetitive arousal from sleep. Inspiratory effort against the airway obstruction causes an increase in left ventricular wall stress. Frequent episodes of hypoxemia have been associated with increased sympathetic activity, endothelial dysfunction and systemic inflammation. Epidemiologic observations indicted that OSA is associated with atrial fibrillation (AF) and is an increased risk for development of AF in individuals <65 years of age. Patients with OSA have a peak in sudden cardiac death during sleeping hours, when peoples without OSA show a nadir. Majority of cardiac patients with moderate-to-severe OSA, however, remain undiagnosed. This is due mainly to cost and inconvenience of the standard diagnosis of sleep apnea by polysomnographic examination. Each episode of sleep apnea is accompanied by bradycardia followed by abrupt tachycardia upon its cessation, resulting in a characteristic heart rate pattern, called cyclic variation of heart rate (CVHR). Recently, we developed an algorithm, named autocorrelated wave detection with adaptive threshold (ACAT) for detecting CVHR from Holter ECG recording during sleep. ACAT may provide a powerful screening tool for sleep apnea among cardiac patients and CVHR may be a new index in routine Holter ECG examinations for cardiac arrhythmias. © 2011, Japanese Heart Rhythm Society. All rights reserved.
  • CARDIOVASCULAR TOLERANCE AND AUTONOMIC NERVOUS RESPONSES IN UNSEDATED UPPER GASTROINTESTINAL SMALL-CALIBER ENDOSCOPY: A COMPARISON BETWEEN TRANSNASAL AND PERORAL PROCEDURES WITH NEWLY DEVELOPED MOUTHPIECE, Hiromi Kataoka, Junichiro Hayano, Takashi Mizushima, Mamoru Tanaka, Eiji Kubota, Takaya Shimura, Tsutomu Mizoshita, Satoshi Tanida, Takeshi Kamiya, Shunsuke Nojiri, Seiji Mukai, Kiyoshi Mizuno, Takashi Joh, DIGESTIVE ENDOSCOPY, 23, (1) 78 - 85,   2011年01月, 査読有り, Background: Transnasal esophagogastroduodenoscopy (EGD) with small-caliber endoscopy appears to be less stressful to the cardiovascular system and has good patient tolerance. ENDO LEADER, a newly developed mouthpiece for peroral EGD with small-caliber endoscopy, is expected to reduce patient stress. We compared the patient acceptance, cardiovascular tolerance and autonomic nervous responses between transnasal EGD and peroral EGD with ENDO LEADER. Patients and Methods: A total of 130 patients (transnasal group, 77; peroral group, 53) were enrolled. Pulse rate (P), blood pressure (BP), and peripheral blood oxygen saturation (SpO(2)) were monitored. Acceptance of EGD was also assessed. Autonomic nervous responses were evaluated through analysis of heart rate variability using amplitude of the high-frequency component (HF) and low-frequency-to-high-frequency power ratio (LF/HF) as indices of cardiac vagal activity and sympathetic activity, respectively. Results: Analysis of patient acceptance showed no differences between the two groups, except with regard to nasal pain. Increases in BP and P between before and during EGD examination were significantly higher in the peroral group. Although throat pain and overall tolerance scores were significantly correlated with Delta BP and Delta P, no correlations with nasal pain score were noted. Heart rate variability analysis revealed that heart rate increased significantly in the peroral group, but there were no differences in Delta HF or Delta LF/HF between the two groups. Conclusions: Patient acceptance was not significantly different between the transnasal and peroral with ENDO LEADER groups; however, transnasal EGD appears to be less stressful to the sympathetic nervous system, leading to smaller elevations in BP, P and heart rate.
  • Increased non-Gaussianity of heart rate variability predicts cardiac mortality after an acute myocardial infarction, Junichiro Hayano, Ken Kiyono, Zbigniew R. Struzik, Yoshiharu Yamamoto, Eiichi Watanabe, Phyllis K. Stein, Lana L. Watkins, James A. Blumenthal, Robert M. Carney, FRONTIERS IN PHYSIOLOGY, 2,   2011年, 査読有り, Non-Gaussianity index (lambda) is a new index of heart rate variability (HRV) that characterizes increased probability of the large heart rate deviations from its trend. A previous study has reported that increased lambda is an independent mortality predictor among patients with chronic heart failure. The present study examined predictive value of lambda in patients after acute myocardial infarction (AMI) Among 670 post-AMI patients, we performed 24-h Holter monitoring to assess lambda and other HRV predictors, including SD of normal-to-normal interval, very-low frequency power, scaling exponent alpha(1) of detrended fluctuation analysis, deceleration capacity, and heart rate turbulence (HRT). At baseline, lambda was not correlated substantially with other HRV indices (|r| < 0.4 with either indices) and was decreased in patients taking beta-blockers (P= 0.04). During a median follow-up period of 25 months, 45 (6.7%) patients died (32 cardiac and 13 non-cardiac) and 39 recurrent non-fatal AMI occurred among survivors. While all of these HRV indices but lambda were significant predictors of both cardiac and non-cardiac deaths, increased lambda predicted exclusively cardiac death (RR [95% Cl], 1.6 [1.3-2.0] per 1 SD increment, P< 0.0001). The predictive power of increased lambda was significant even after adjustments for clinical risk factors, such as age, diabetes, left ventricular function, renal function, prior AMI, heart failure, and stroke, Killip class, and treatment ([95% Cl], 1.4 [1.1-2.0] per 1 SD increment, P=0.01). The prognostic power of increased lambda for cardiac death was also independent of all other HRV indices and the combination of increased lambda and abnormal HRT provided the best predictive model for cardiac death. Neither lambda nor other HRV indices was an independent predictor of AMI recurrence. Among post-AM I patients, increased lambda is associated exclusively with increased cardiac mortality risk and its predictive power is independent of clinical risk factors and of other HRV predictors.
  • Diagnosis of Sleep Apnea by the Analysis of Heart Rate Variation: A Mini Review, Junichiro Hayano, Eiichi Watanabe, Yuji Saito, Fumihiko Sasaki, Kiyohiro Kawai, Itsuo Kodama, Hiroki Sakakibara, 2011 ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY (EMBC), 2011, 7731 - 7734,   2011年, 査読有り, Cyclic variation of heart rate (CVHR) associated with sleep apnea/hypopnea episodes has been suggested as a marker of sleep disordered breathing (SDB). This study examined the utility of ECG-based CVHR detection for diagnosing SDB using simultaneous polysomnography as the reference standard. We used a previously developed automated CVHR detection algorithm (autocorrelated wave detection with adaptive threshold, ACAT) that provides the number of CVHR per hour (CVHR index). The ACAT was refined using a polysomnographic database of 194 subjects with various severities of SDB and then, applied to a single channel ECG obtained during standard overnight polysomnography in 862 consecutive subjects referred for SDB diagnosis. Using multiple thresholds of CVHR index >= 38 and <27, positive and negative predictive values of 95.6% and 95.1%, respectively, were achieved for detecting and excluding subjects with apnea-hypopnea index (AHI) >= 30, leaving 58 (6.7%) unclassified subjects. Positive and negative likelihood ratios (LRs) were 97.3 and 0.23, respectively. Also, thresholds of CVHR index >= 29 and <7 provided 96.1% and 95.1% of positive and negative predictive values, respectively, for subjects with AHI >= 15 (LRs, 50.6 and 0.11), leaving 426 (49.4%) unclassified subjects. The CVHR correlated with the AHI (r = 0.86) and showed the limits of agreement with the AHI of 19.6 and -18.6. Automated detection of CVHR by the ACAT algorithm provides useful screening tool for both increasing and decreasing probability of moderate and sever SDB with adequate thresholds.
  • Asymmetric intermittency observed in human heart rate dynamics, Ken Kiyono, Zbigniew R. Struzik, Junihiro Hayano, 2011 ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY (EMBC), 2011, 7743 - 7746,   2011年, 査読有り, To gain a deeper understanding of intermittent fluctuations observed in complex, real-world systems, we propose positive-or negative-directional non-Gaussian statistics. As a numerical example of asymmetric intermittent fluctuations, we heuristically introduce a random cascade-type model. Using our method, it is demonstrated that the asymmetric properties of heart rate variability depend on aging. This provides new insight into the physiological mechanism controlling heart rate dynamics in health and in autonomic disorder.
  • Effect of HRV Biofeedback on Cardiorespiratory Resting Function During Sleep, Masahito Sakakibara, Junichiro Hayano, Leo Oikawa, Maria Karavidas, Paul Lehrer, APPLIED PSYCHOPHYSIOLOGY AND BIOFEEDBACK, 35, (4) 326 - 326,   2010年12月, 査読有り
  • Cost-Effective Screening for Obstructive Sleep Apnea by Automated ECG Detection of Cyclic Variation of Heart Rate, Junichiro Hayano, Eiichi Watanabe, Yuji Saito, Fumihiko Sasaki, Keisaku Fujimoto, Tetsuo Nomiyama, Kiyohiro Kawai, Itsuo Kodama, Hiroki Sakakibara, CIRCULATION, 122, (21) ,   2010年11月, 査読有り
  • Depression, Alexithymia and Long-Term Mortality in Chronic Hemodialysis Patients, Masayo Kojima, Junichiro Hayano, Sadao Suzuki, Hachiro Seno, Hirotake Kasuga, Hiroshi Takahashi, Takanobu Toriyama, Hirohisa Kawahara, Toshiaki A. Furukawa, PSYCHOTHERAPY AND PSYCHOSOMATICS, 79, (5) 303 - 311,   2010年, 査読有り, Background: Depression increases the risk of mortality in hemodialysis patients. Alexithymia, a disorder of affect regulation, has also been reported to be associated with mortality risk in the general population. We conducted a prospective study to estimate the independent impact of depression and alexithymia on long-term mortality. Methods: A total of 230 hemodialysis outpatients, with a mean age of 56.3 +/- 9.6 years, completed a batch of self-report measures including the Beck Depression Inventory-II (BDI-II), the 20-item Toronto Alexithymia Scale (TAS-20) and the 36-item Short Form Health Survey (SF-36). Survival status was confirmed every 6 months for up to 5 years. The presence of depression and alexithymia was defined by a BDI-II score of >= 14 and a TAS-20 score of >= 61, respectively. Results: During the follow-up period, 27 deaths were confirmed. Both depression and alexithymia were associated with an increased risk for all-cause mortality; the age-and sex-adjusted hazard ratio for depression was 2.36 (95% CI: 1.08-5.15; p = 0.03) and that for alexithymia was 4.29 (95% CI: 1.95-9.42; p < 0.001). Depression lost its statistical significance after controlling for alexithymia, whereas alexithymia remained significant even after adjusting for the baseline depression, health status (the summary scores of the SF-36), marital status and clinical covariates (multivariate adjusted hazard ratio = 3.62; 95% CI: 1.32-9.93; p = 0.01). Conclusions: Alexithymia is a strong independent risk factor for all-cause mortality in hemodialysis patients. Copyright (C) 2010 S. Karger AG, Basel
  • Nighttime heart rate and survival in depressed patients post acute myocardial infarction, Robert M. Carney, Brian Steinmeyer, Kenneth E. Freedland, James A. Blumenthal, Phyllis K. Stein, William A. Steinhoff, William B. Howells, Lisa F. Berkman, Lana L. Watkins, Susan M. Czajkowski, Peter P. Domitrovich, Matthew M. Burg, Junichiro Hayano, Allan S. Jaffe, PSYCHOSOMATIC MEDICINE, 70, (7) 757 - 763,   2008年09月, 査読有り, Objectives: To determine if: 1) depressed patients with a recent acute myocardial infarction (AMI) have higher nighttime heart rate (FIR) than nondepressed patients, and 2) elevated nighttime FIR is associated with decreased survival post AMI. Depression is a risk factor for mortality post AMI. It is also associated with sleep disturbances and with elevated FIR, which may be more pronounced at night. Resting and 24-hour FIR have been found to predict mortality in patient and community samples. Methods: Ambulatory electrocardiographic data were obtained from 333 depressed patients and 383 nondepressed patients with recent AMI. They were followed for Lip to 30 months (median 24 months). Results: Depressed patients had higher nighttime FIR (70.7 +/- 0.7 versus 67.7 +/- 0.6 beats per minute (bpm); p=.001), and daytime Flit (76.4 +/- 0.7 versus 74.2 +/- 0.6 bpm; p = .02) than nondepressed patients, even after adjusting for potential confounds. Depression (hazard ratio (Haz R) = 2.19; p = .02) and nighttime HR (Haz R = 1.03; p = .004), but not daytime FIR, predicted survival after adjusting for other major predictors and for each other. The interaction between nighttime FIR and depression on survival approached, but did not achieve, significance (p = .08). Conclusions: Mean day and nighttime FIR values are higher in depressed patients than in nondepressed patients post AMI. Depression and elevated nighttime FIR, but not daytime FIR, are independent predictors Of Survival in these patients. Although depressed patients have a higher nighttime FIR than nondepressed patients, nighttime FIR predicts mortality in both depressed and nondepressed patients.
  • Impact of real-world stress on cardiorespiratory resting function during sleep in daily life, Masahito Sakakibara, Takayoshi Kanematsu, Fumihiko Yasuma, Junichiro Hayano, PSYCHOPHYSIOLOGY, 45, (4) 667 - 670,   2008年07月, 査読有り, To examine if real-world stress affects the restorative function of sleep in daily life, we studied the impact of college examinations on cardiorespiratory resting function during sleep. In healthy college students, at 1 week before, the day before, and the first day of semester-end examinations pulse wave signal during sleep at their own residences was measured continuously with a wristband-shaped wireless transdermal photoelectric sensor. The cardiorespiratory resting function was assessed quantitatively as the power of a high-frequency component of pulse rate variability, a surrogate measure of respiratory sinus arrhythmia. Changes in anxiety were also evaluated with a state anxiety questionnaire. On the day before the examinations, compared with 1 week before, the score of state anxiety increased and the HF component of pulse rate variability decreased. Among college students, anxiety about college examinations may be accompanied by suppression of the cardiorespiratory resting function during sleep.
  • Increased heteroscedasticity of heart rate in fatal heart failure, Z. R. Struzik, K. Kiyono, J. Hayano, E. Watanabe, Y. Yamamoto, EPL, 82, (2) ,   2008年04月, Healthy human heart rate is known to fluctuate in a highly complex manner, displaying complexity characteristics such as those shared by physical systems at a critical state. It is, however, widely believed that chronic heart failure reduces this complexity and that heart rate data from chronic-heart-failure patients can be used for the validation of complexity measures and paradigms applicable both to heart rate and more generally to assess any system's complexity. Here, we counter the above belief, showing an increase in fluctuations and in complexity of heart rate in chronic-heart-failure patients, in particular those at risk of death. This is supported by evidence of increased non-Gaussianity and heteroscedasticity resulting from the emergence of a characteristic correlation scale in the magnitude correlation landscape. Copyright (c) EPLA, 2008.
  • Non-Gaussian heart rate as an independent predictor of mortality in patients with chronic heart failure, Ken Kiyono, Junichiro Hayano, Eiichi Watanabe, Zbigniew R. Struzik, Yoshiharu Yamamoto, HEART RHYTHM, 5, (2) 261 - 268,   2008年02月, 査読有り, BACKGROUND Morbidity and mortality due to chronic heart failure remain unacceptably high despite effective drug therapies, and the search for a better risk predictor is ongoing. Statistics derived from beat-to-beat fluctuations in heart rate or heart rate variability (HRV) have been used for this purpose, but the current predictability level is Low or moderate at best. OBJECTIVE The purpose of this study was to evaluate whether a recently proposed non-Gaussian index of HRV is a significant and independent mortality predictor in patients with congestive heart failure (CHF). METHODS Twenty-four-hour Hotter ECGs from 108 CHF patients were evaluated. Thirty-nine (36.1%) of the patients died during the follow-up period of 33 +/- 17 months. Cox proportional hazards regression analysis was performed to determine factors related to all-cause mortality. The factors evaluated derived from clinical information, including plasma brain natriuretic peptide, conventional time- and frequency-domain and fractal HRV measures, and a recently proposed non-Gaussian index X of HRV. RESULTS The short-term (< 40 beats) non-Gaussian index lambda(40) (hazard ratio per increment of unit standard deviation 1.64, 95% confidence interval [1.23, 2.18], P <.001) and the long-term (< 1,000 beats) index lambda(1000) (hazard ratio 1.42, 95% confidence interval [1.07, 2.18], P <.02), together with brain natriuretic peptide (hazard ratio 2.26, 95% confidence interval [1.45, 3.53], P <.001), are significant univariate risk predictors of mortality. In a multivariate model, lambda(40) (1.49, [1.13, 1.96], P <.005) and brain natriuretic peptide (2.39, [1.53, 3.75], P <.001) are independent predictors of the survival statistics of patients. None of the conventional HRV measures have predicted the mortality of patients in a significant and independent manner. CONCLUSION The results of this study indicate the usefulness of the short-term non-Gaussian index of HRV for risk prediction in patients with CHF.
  • Loss of fractal heart rate dynamics in depressive hemodialysis patients, Masayo Koilma, Junichiro Hayano, Hidekatsu Fukuta, Sechir Sakata, Seiji Mukai, Nobuyuki Ohte, Hachiro Seno, Takanu Toriyama, Hirsa Kawahara, Toshiaki A. Furukawa, Shinkan Tokudome, PSYCHOSOMATIC MEDICINE, 70, (2) 177 - 185,   2008年02月, 査読有り, Objective: To assess the relationship between depression, reduced heart rate (HR) variability, and altered HR dynamics among patients with end-stage renal disease who are receiving hemodialysis (HD) therapy. Methods: We analyzed the 24-hour electrocardiograms of 119 outpatients receiving chronic HD. HR variability was quantified with the standard deviation of normal-to-normal R-R intervals, the triangular index, and the powers of the high- (HF), low- (LF), very-low (VLF), and ultra-low frequency (ULF) components. Nonlinear HP dynamics was assessed with the short-term (alpha(1)) and long-term (alpha(2)) scaling exponents of the detrended fluctuation analysis and approximate entropy. The depression level was assessed using the Beck Depression Inventory, Second Edition (BDI-II). FIR variability and dynamics measurements were compared by gender, diabetes, and depression with adjustment for age and serum albumin concentration. Results: Most indices of FIR variability and dynamics were negatively cot-related with age, serum albumin concentration, depression score, and were lower in women and patients with diabetes. The alpha(2) was inversely associated with these variables. Depressed men had significantly lower HF, LF, VLF, and marginally lower ULF than nondepressed persons after adjustment for diabetes and other covariates; no difference in depression was observed in women, The alpha(2) showed marginally significant difference in depression independent front gender and diabetes. Conclusions: Among the patients who received HD, depression is associated with reduced HR variability and loss of fractal HR dynamics. However, the influence of depression on HR variability may vary by gender and physiological backgrounds. Further prospective studies are necessary to confirm their association with poor prognosis.
  • Relationship between blood pressure obtained from the upper arm with a cuff-type sphygmomanometer and central blood pressure measured with a catheter-tipped micromanometer, Nobuyuki Ohte, Tomoaki Saeki, Hiromichi Miyabe, Seichiro Sakata, Seiji Mukai, Junichiro Hayano, Kiyomi Niki, Motoaki Sugawara, Genjiro Kimura, HEART AND VESSELS, 22, (6) 410 - 415,   2007年11月, 査読有り, Recently, the importance of central blood pressure for cardiovascular risk stratification has been emphasized. Accordingly, the differences in peak systolic and bottom diastolic pressures between the ascending aorta and the brachial artery should be clarified. Study subjects consisted of 82 consecutive patients with suspected coronary artery disease who underwent cardiac catheterization, and in whom ascending aortic pressure waveform was obtained using a catheter-tipped micromanometer, and at the same time systolic and diastolic pressures were measured (single measurement) from the right upper arm with a cuff-type sphygmomanometer based on the oscillometric technique. No significant systematic difference (bias) was found between the peak pressure obtained in the ascending aorta and the systolic pressure from the right upper arm (133.6 +/- 25.1 vs 131.8 +/- 21.5 mmHg, not significant). Bland-Altman analysis showed only a small bias of +1.8 mmHg, and the limits of agreement were 25.4 mmHg and -21.8 mmHg. In contrast, the bottom pressure in the ascending aorta was significantly lower compared with the diastolic pressure from the upper arm (68.5 +/- 10.7 vs 73.0 +/- 12.4 mmHg, P < 0.0001). Bland-Altman analysis showed a small but significant bias of -4.5 mmHg, and the limits of agreement were 14.1 mmHg and -23.1 mmHg. The observed biases seemed to remain within practical range. However, random variation in the two measurements was rather large. This is considered to be caused by the random error in the single measurement with the cuff-type sphygmomanometer.
  • Independent associations of alexithymia and social support with depression in hemodialysis patients, Masayo Kojima, Junichiro Hayano, Shinkan Tokudome, Sadao Suzuki, Koichi Ibuki, Hiroshi Tomizawa, Atsuro Nakata, Hachiro Seno, Takanobu Toriyama, Hiroshi Kawahara, Toshiaki A. Furukawa, JOURNAL OF PSYCHOSOMATIC RESEARCH, 63, (4) 349 - 356,   2007年10月, 査読有り, Objective: The influences of alexithymia and social support on depression among chronically ill patients were examined prospectively. Methods: The study population was 230 outpatients receiving chronic hemodialysis (HD) therapy. The Beck Depression Inventory-II (BDI-II), the 20-item Toronto Alexithymia Scale (TAS-20), and two subscales of the Social Support Questionnaire were given to the subjects. The BDI-II was readministered after a 6-month interval, and subjects who showed deterioration in their depression score above the level predicted from their baseline score were identified. Multivariate logistic analysis adjusted for age, gender, cause of dialysis, and psychosocial variables were performed. Results: Baseline depression was significantly and independently associated with alexithymia and low satisfaction with available support. Deterioration of depression after 6 months was predicted by alexithymia and poor available support. Conclusions: Alexithymia and reduced social support might have independent associations with the presence and the prognosis of depression among HD patients. (c) 2007 Elsevier Inc. All rights reserved.
  • Cardiac vagal activation by adrenocorticotropic hormone treatment in infants with West syndrome, Ayako Hattori, Junichiro Hayano, Shinji Fujimoto, Naoki Ando, Kumiko Mizuno, Michi Kamei, Satoru Kobayashi, Tatsuya Ishikawa, Hajime Togari, TOHOKU JOURNAL OF EXPERIMENTAL MEDICINE, 211, (2) 133 - 139,   2007年02月, 査読有り, West syndrome (WS) is a generalized epileptic syndrome of infancy and early childhood with various etiologies, and consists of a triad of infantile spasm, arrest or regress of psychomotor development and specific electroencephalogram (EEG) pattern of hypsarrhythmia. WS had been believed to be refractory, but recent evidence supports effectiveness of adrenocorticotropic hormone (ACTH) treatment. The ACTH treatment, however, has a problem that it is often accompanied by adverse autonomic symptoms. We therefore examined heart rate variability (HRV) for assessing cardiac autonomic functions in WS and prospectively observed the changes during ACTH treatment. We studied 15 patients with WS and 9 age-matched controls during sleep (EEG stage 2). Compared with controls, the patients with WS were greater in the low-frequency component (LF) of HRV, an index reflecting sympatho-vagal interaction (p = 0.02), but were comparable for high-frequency component (HF) and LF-to-HF ratio (LF/HF), indices reflecting cardiac vagal activity and sympathetic predominance, respectively. During ACTH treatment, heart rate decreased (p < 0.01), LF and HF increased (p < 0.01), and LF/HF did not differ significantly. These results indicate that West syndrome might be accompanied by autonomic changes and that ACTH treatment enhances parasympathetic function and causes bradycardia.
  • Heart rate turbulence, depression, and survival after acute myocardial infarction, Robert M. Carney, William B. Howells, James A. Blumenthal, Kenneth E. Freedland, Phyllis K. Stein, Lisa F. Berkman, Lana L. Watkins, Susan M. Czajkowski, Brian Steinmeyer, Junichiro Hayano, Peter P. Domitrovich, Matthew M. Burg, Allan S. Jaffe, PSYCHOSOMATIC MEDICINE, 69, (1) 4 - 9,   2007年01月, 査読有り, Objective: Depression is a risk factor for mortality after acute myocardial infarction (AMI), possibly as a result of altered autonomic nervous system (ANS) modulation of heart rate (HR) and rhythm. The purposes of this study were to determine: a) whether depressed patients are more likely to have an abnormal HR response (i.e., abnormal turbulence) to premature ventricular contractions (VPCs), and b) whether abnormal HR turbulence accounts for the effect of depression on increased mortality after AMI. Methods: Ambulatory electrocardiographic data were obtained from 666 (316 depressed, 350 nondepressed) patients with a recent AMI; 498 had VPCs with measurable HR turbulence. Of these, 260 had normal, 152 had equivocal, and 86 had abnormal HR turbulence. Patients were followed for up to 30 (median = 24) months. Results: Depressed patients were more likely to have abnormal HR turbulence (risk factor adjusted odds ratio = 1.8; 95% confidence interval [CI] = 1.0-3.0; p =.03) and have worse survival (odds ratio = 2.4; 95% Cl = 1.2-4.6; p =.02) than nondepressed patients. When HR turbulence was added to the model, the adjusted hazard ratio for depression decreased to 1.9 (95% Cl = 0.9-3.8; p =.08), and to 1.6 (95% Cl = 0.8-3.4; p =.18) when a measure of HR variability (LnVLF) was added. The hazard was found to differ over time with depression posing little risk for mortality in year I but greater risk in years 2 and 3 of the follow up. Conclusion: ANS dysregulation may partially mediate the increased risk for mortality in depressed patients with frequent VPCs after an AMI.
  • Changes in chemosensitivity with continuous positive airway pressure of 5 cmH(2)O for Cheyne-Stokes respiration in congestive heart failure, Fumihiko Yasuma, Toshimitsu Mori, Masahiro Noguchi, Satoshi Kuru, Masaaki Konagaya, Jun-ichiro Hayano, RESPIRATION, 74, (4) 475 - 477,   2007年, 査読有り
  • Exponential distribution of long heart beat intervals during atrial fibrillation and their relevance for white noise behaviour in power spectrum, Thomas Hennig, Philipp Maass, Junichiro Hayano, Stefan Heinrichs, JOURNAL OF BIOLOGICAL PHYSICS, 32, (5) 383 - 392,   2006年11月, 査読有り, The statistical properties of heart beat intervals of 130 long-term surface electrocardiogram recordings during atrial fibrillation (AF) are investigated. We find that the distribution of interbeat intervals exhibits a characteristic exponential tail, which is absent during sinus rhythm, as tested in a corresponding control study with 72 healthy persons. The rate gamma of the exponential decay lies in the range 3-12 Hz and shows diurnal variations. It equals, up to statistical uncertainties, the level of the previously uncovered white noise part of the power spectrum, which is also characteristic for AF. The overall statistical features can be described by decomposing the intervals into two statistically independent times, where the first one is associated with a correlated process with 1/f noise characteristics, while the second one belongs to an uncorrelated process and is responsible for the exponential tail. It is suggested to use gamma as a further parameter for a better classification of AF and for the medical diagnosis. The relevance of the findings with respect to a general understanding of AF is discussed.
  • Vagal nerve activity contributes to improve the efficiency of pulmonary gas exchange in hypoxic humans, Shoji Ito, Hiroshi Sasano, Nobuko Sasano, Junichiro Hayano, Joseph A. Fisher, Hirotada Katsuya, EXPERIMENTAL PHYSIOLOGY, 91, (5) 935 - 941,   2006年09月, 査読有り, The aim of this study was to test our hypothesis that both phasic cardiac vagal activity and tonic pulmonary vagal activity, estimated as respiratory sinus arrhythmia (RSA) and anatomical dead space volume, respectively, contribute to improve the efficiency of pulmonary gas exchange in humans. We examined the effect of blocking vagal nerve activity with atropine on pulmonary gas exchange. Ten healthy volunteers inhaled hypoxic gas with constant tidal volume and respiratory frequency through a respiratory circuit with a respiratory analyser. Arterial partial pressure of O-2 (P-aO2) and arterial oxygen saturation (S-pO2) were measured, and alveolar-to-arterial P-O2 difference (DA-aO2) was calculated. Anatomical dead space (V-D,V-an), alveolar dead space (V-D,V-alv) and the ratio of physiological dead space to tidal volume (V-D,V-phys/V-T) were measured. Electrocardiogram was recorded, and the amplitude of R-R interval variability in the high-frequency component (RRIHF) was utilized as an index of RSA magnitude. These parameters of pulmonary function were measured before and after administration of atropine (0.02 mg kg(-1)). Decreased RRIHF (P < 0.01) was accompanied by decreases in P-aO2 and S-pO2 (P < 0.05 and P < 0.01, respectively) and an increase in DA-aO2 (P < 0.05). Anatomical dead space, V-D,V-alv and V-D,V-phys/V-T increased (P < 0.01, P < 0.05 and P < 0.01, respectively) after atropine administration. The blockade of the vagal nerve with atropine resulted in an increase in V-D,V-an and V-D,V-alv and a deterioration of pulmonary oxygenation, accompanied by attenuation of RSA. Our findings suggest that both phasic cardiac and tonic pulmonary vagal nerve activity contribute to improve the efficiency of pulmonary gas exchange in hypoxic conscious humans.
  • Long-term efficacy of acetazolamide on Cheyne-Stokes respiration in congestive heart failure [1], Fumihiko Yasuma, Toyoaki Murohara, Junichiro Hayano, American Journal of Respiratory and Critical Care Medicine, 174,   2006年08月15日
  • Long-term efficacy of acetazolamide on Cheyne-Stokes respiration in congestive heart failure., Yasuma F, Murohara T, Hayano J, American journal of respiratory and critical care medicine, 174, (4) 479; author reply 479 - 80,   2006年08月, 査読有り
  • Quality of care associated with number of cases seen and self-reports of clinical competence for Japanese physicians-in-training in internal medicine., Hayashino Y, Fukuhara S, Matsui K, Noguchi Y, Minami T, Bertenthal D, Peabody JW, Mutoh Y, Hirao Y, Kikawa K, Fukumoto Y, Hayano J, Ino T, Sawada U, Seino J, Higuma N, Ishimaru H, BMC medical education, 6,   2006年06月, 査読有り
  • Aging of complex heart rate dynamics, ZR Struzik, J Hayano, R Soma, S Kwak, Y Yamamoto, IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING, 53, (1) 89 - 94,   2006年01月, 査読有り, We reveal unexpected origins of age induced departure from 1/f-type temporal scaling in healthy human heart rate. Contrary to the widely established view, we provide evidence that age induced dynamical imbalance in the autonomic control is not due to the emergent functional dominance of the sympathetic nervous system (SNS), but due to emerging (age dependent) relative dynamic dominance of the parasympathetic nervous system function. In particular, we demonstrate that the age induced alterations of healthy heart rate dynamics asymptotically resemble those in so-called primary autonomic failure with neurogenic SNS dysfunction and in other neurodegenerative disorders, including Parkinson's disease even without known autonomic abnormalities. Based upon this, we propose a novel picture of "autonomic aging," characterized by an insufficiency of the SNS function to cope dynamically with various environmental stimuli.
  • Aging of complex heart rate dynamics, ZR Struzik, J Hayano, R Soma, S Kwak, Y Yamamoto, IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING, 53, (1) 89 - 94,   2006年01月, 査読有り, We reveal unexpected origins of age induced departure from 1/f-type temporal scaling in healthy human heart rate. Contrary to the widely established view, we provide evidence that age induced dynamical imbalance in the autonomic control is not due to the emergent functional dominance of the sympathetic nervous system (SNS), but due to emerging (age dependent) relative dynamic dominance of the parasympathetic nervous system function. In particular, we demonstrate that the age induced alterations of healthy heart rate dynamics asymptotically resemble those in so-called primary autonomic failure with neurogenic SNS dysfunction and in other neurodegenerative disorders, including Parkinson's disease even without known autonomic abnormalities. Based upon this, we propose a novel picture of "autonomic aging," characterized by an insufficiency of the SNS function to cope dynamically with various environmental stimuli.
  • Assessment of pulse rate variability by the method of pulse frequency demodulation., Hayano J, Barros AK, Kamiya A, Ohte N, Yasuma F, Biomedical engineering online, 4,   2005年11月, 査読有り
  • Low-frequency oscillation of sympathetic nerve activity decreases during development of tilt-induced syncope preceding sympathetic withdrawal and bradycardia, A Kamiya, J Hayano, T Kawada, D Michikami, K Yamamoto, H Ariumi, S Shimizu, K Uemura, T Miyamoto, T Aiba, K Sunagawa, M Sugimachi, AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY, 289, (4) H1758 - H1769,   2005年10月, 査読有り, Sympathetic activation during orthostatic stress is accompanied by a marked increase in low-frequency (LF, similar to 0.1-Hz) oscillation of sympathetic nerve activity (SNA) when arterial pressure (AP) is well maintained. However, LF oscillation of SNA during development of orthostatic neurally mediated syncope remains unknown. Ten healthy subjects who developed head-up tilt (HUT)-induced syncope and 10 age-matched nonsyncopal controls were studied. Nonstationary time-dependent changes in calf muscle SNA (MSNA, microneurography), R-R interval, and AP ( finger photoplethysmography) variability during a 15-min 60 degrees HUT test were assessed using complex demodulation. In both groups, HUT during the first 5 min increased heart rate, magnitude of MSNA, LF and respiratory high-frequency (HF) amplitudes of MSNA variability, and LF and HF amplitudes of AP variability but decreased HF amplitude of R-R interval variability ( index of cardiac vagal nerve activity). In the nonsyncopal group, these changes were sustained throughout HUT. In the syncopal group, systolic AP decreased from 100 to 60 s before onset of syncope; LF amplitude of MSNA variability decreased, whereas magnitude of MSNA and LF amplitude of AP variability remained elevated. From 60 s before onset of syncope, MSNA and heart rate decreased, index of cardiac vagal nerve activity increased, and AP further decreased to the level at syncope. LF oscillation of MSNA variability decreased during development of orthostatic neurally mediated syncope, preceding sympathetic withdrawal, bradycardia, and severe hypotension, to the level at syncope.
  • Acute effects of cigarette smoking on the heart rate variability of taxi drivers during work, F Kobayashi, T Watanabe, Y Akamatsu, H Furui, T Tomita, R Ohashi, J Hayano, SCANDINAVIAN JOURNAL OF WORK ENVIRONMENT & HEALTH, 31, (5) 360 - 366,   2005年10月, 査読有り, Objectives This study attempted to clarify the acute effects of cigarette smoking on autonomic nervous function among taxi drivers under ordinary work conditions. Methods Holier electrocardiographic recordings from 20 healthy middle-aged taxi drivers were analyzed for the time from 0800 in the morning to 0159 at night. The amplitudes (milliseconds) of the high-frequency (HF) component and the ratio of the low-frequency component to HF (LF/HF) were calculated as changes in the R-R interval, and time-course changes were investigated by a complex demodulation method. The exact starting time of smoking was identified with the use of a specially designed cigarette lighter. The mean LF/HF and HF for 5 minutes immediately prior to smoking were calculated as the baseline, and the means for every 5 minutes up to 15 minutes were calculated. The average values of these parameters for all of the cigarette smoking within the same time span of 0800-1659 and 1700-0159 were also determined. Results The LF/HF significantly increased (P<0.05) within 5 minutes from the baseline immediately after smoking. This significant change in LF/HF was observed only at night. Although the interactive effect of the time of day on time course changes was not significant for the LF/HF or HF, the reactivity to increase LF/HF and decrease HF was more prominent at night. Conclusions Cigarette smoking significantly increased LF/HF within 5 minutes during ordinary taxi driving. Nighttime smoking seemed to have a more potent acute effect on the cardiac modulation of taxi drivers than in the daytime. The sympathomimetic and parasympatho-withdrawal response of smoking may play an additional role in increasing cardiac risk among taxi drivers.
  • Effects of the muscle pump and body posture on cardiovascular responses during recovery from cycle exercise, T Takahashi, J Hayano, A Okada, T Saitoh, A Kamiya, EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY, 94, (5-6) 576 - 583,   2005年08月, 査読有り, The purpose of the study was to characterize the effects of muscular contractions (the muscle pump) and body posture on cardiovascular responses during recovery from moderate exercise in the upright-sitting or supine positions. Heart rate (HR), stroke volume (SV), and cardiac output (CO) were measured in seven young male subjects at rest and during 10-min of cycle exercise at 60% of peak oxygen uptake (VO2peak). This was followed by either complete rest for 5 min (inactive recovery) or cycling at 20%VO2peak for 5 min (active recovery) in the upright or supine positions. In the upright position, an initial rapid decrease in HR was followed by a gradual decrease in HR, and this response was similar when comparing inactive and active recoveries. Upright SV during inactive recovery decreased gradually to the pre-exercise resting level, whereas upright SV during active recovery remained significantly elevated. In contrast, in the supine position, the HR during active recovery decreased, but remained significantly higher than that during inactive recovery. Changes in supine SV were similar when comparing inactive and active recovery. Thus, maintenance of SV and HR resulted in significantly greater CO during active recovery than during inactive recovery, regardless of body position. HR was greater during supine active-recovery than during supine inactive-recovery, and there was no difference in SV. These data suggest that the muscle pump is less important in facilitating venous return and vagal resumption in the supine position as compared to the upright position.
  • Low heart rate variability and the effect of depression on post-myocardial infarction mortality, RM Carney, JA Blumenthal, KE Freedland, PK Stein, WB Howells, LF Berkman, LL Watkins, SM Czajkowski, J Hayano, PP Domitrovich, AS Jaffe, ARCHIVES OF INTERNAL MEDICINE, 165, (13) 1486 - 1491,   2005年07月, 査読有り, Background: Depression is associated with an increased risk for mortality after acute myocardial infarction (MI). The purpose of this study was to determine whether low heart rate variability (HRV) mediates the effect of depression on mortality. Methods: Twenty-four-hour ambulatory electrocardiograms were obtained from 311 depressed patients with a recent acute MI who were enrolled in the Enhancing Recovery in Coronary Heart Disease (ENRICHD) clinical trial and from 367 nondepressed patients who met the ENRICHD medical inclusion criteria. Standard HRV indexes were extracted from the recordings. Results: The log of very low-frequency (LnVLF) power, an index of HRV derived from power spectral analysis of the electrocardiogram signal (0.0033-0.04 Hz [in milliseconds squared]), was lower in the depressed than in the nondepressed patients (P <.001). There were 47 deaths (6.1%) during a 30-month follow-up. After adjusting for potential confounders, the depressed patients remained at higher risk for all-cause mortality compared with the nondepressed patients (hazard ratio, 2.8; 95% confidence interval [CI], 1.4-5.4-1 P <.003). When LnVLF power was entered into the model, the hazard ratio for depression dropped to 2.1 (95% CI, 1.1-4.2; P=.03). The proportion of the risk for depression attributable to LnVLF power was 0.27 (95% CI, 0.23-0.3 1; P <.001). Conclusions: Low HRV partially mediates the effect of depression on survival after acute MI. This finding helps to clarify the physiological mechanisms underlying depression's role as a risk factor for mortality in patients with coronary heart disease. It also raises the possibility that treatments that improve both depression and HRV might also improve survival in these patients.
  • Usefulness of plasma brain-type natriuretic peptide level to differentiate left ventricular diastolic dysfunction from preserved diastolic function in patients with systolic dysfunction, T Goto, N Ohte, H Miyabe, S Sakata, K Asada, S Mukai, J Hayano, G Kimura, AMERICAN JOURNAL OF CARDIOLOGY, 95, (11) 1383 - 1385,   2005年06月, 査読有り, The extent of left ventricular (LV) diastolic dysfunction is related to the finding that some patients with cardiomegaly due to LV systolic dysfunction have good exercise tolerance, although others have limited tolerance. A brain-type natriuretic peptide level of >= 104 pg/ml reliably enables the detection of relatively worse LV diastolic function in patients with systolic dysfunction, and this value may provide clinically useful information for the management of patients with cardiomegaly. (c) 2005 by Excerpta Medica Inc.
  • Effects of exercise and stress management training on markers of cardiovascular risk in patients with ischemic heart disease: a randomized controlled trial., Blumenthal JA, Sherwood A, Babyak MA, Watkins LL, Waugh R, Georgiades A, Bacon SL, Hayano J, Coleman RE, Hinderliter A, JAMA, 293, (13) 1626 - 1634,   2005年04月, 査読有り
  • TI-201 washout rate in remote normal regions in patients with prior myocardial infarction and left ventricular remodeling, T Goto, N Ohte, H Miyabe, S Mukai, S Sakata, J Hayano, G Kimura, JOURNAL OF NUCLEAR CARDIOLOGY, 12, (2) 179 - 185,   2005年03月, 査読有り, Background. Myocardial characteristics of remote normal regions in patients with myocardial infarction (MI) and left ventricular (LV) remodeling have not been fully elucidated. Thus, we investigated this issue from the viewpoint of myocardial TI-201 dynamics. Methods and Results. In 14 patients with prior anterior MI, 10 with inferior MI, and 14 age-matched patients with atypical chest pain served as controls; exercise stress TI-201 SPECT and cardiac catheterization were performed. TI-201 washout rate was calculated for 8 myocardial segments, and LV end-diastolic volume index was obtained as a parameter of LV remodeling. LV end-diastolic volume index was greater in anterior MI patients than in control patients; in contrast, no significant difference was observed between inferior MI patients and control patients. The washout rate in remote normal regions was significantly less in anterior MI patients than in the corresponding segments in control patients (39.8% +/- 8.7% vs 48.4% +/- 4.4%, P < .01). There was no significant difference between inferior MI patients and control patients (43.6% +/- 6.9% vs 47.8% +/- 4.5%). Conclusions. Reduced TI-201 washout rates in remote normal regions are found in patients with anterior MI and LV remodeling. Subclinical myocardial ischemia during exercise in remote normal regions exists and may be related to the pathologic condition of such LV walls.
  • 1/f scaling in heart rate requires antagonistic autonomic control, ZR Struzik, J Hayano, S Sakata, S Kwak, Y Yamamoto, PHYSICAL REVIEW E, 70, (5) ,   2004年11月, 査読有り, We present systematic evidence for the origins of 1/f-type temporal scaling in human heart rate. The heart rate is regulated by the activity of two branches of the autonomic nervous system: the parasympathetic (PNS) and the sympathetic (SNS) nervous systems. We examine alterations in the scaling property when the balance between PNS and SNS activity is modified, and find that the relative PNS suppression by congestive heart failure results in a substantial increase in the Hurst exponent H towards random-walk scaling 1/f(2) and a similar breakdown is observed with relative SNS suppression by primary autonomic failure. These results suggest that I If scaling in heart rate requires the intricate balance between the antagonistic activity of PNS and SNS.
  • Heartbeat synchronizes with respiratory rhythm only under specific circumstances [6] (multiple letters), Evgeny Vaschillo, Bronya Vaschillo, Paul Lehrer, Paul Lehrer, Fumihiko Yasuma, Fumihiko Yasuma, Jun Ichiro Hayano, Chest, 126, 1385 - 1387,   2004年10月01日
  • Evaluation of whole left ventricular systolic performance and local myocardial systolic function in patients with prior myocardial infarction using global long-axis myocardial strain, N Ohte, H Narita, H Miyabe, N Takada, T Goto, H Mizuno, K Asada, J Hayano, G Kimura, AMERICAN JOURNAL OF CARDIOLOGY, 94, (7) 929 - 932,   2004年10月, 査読有り, Left ventricular (LV) global strain along its long axis during systole, which is obtained by dividing mitral annular excursion by the distance from the mitral annulus to the LV apex at end-diastole, can be used to assess whole LV systolic performance. The evaluation of LV wall function using this parameter suggests that previous myocardial infarction (MI) causes, long-axis myocardial function in remote normal LV walls, as well as in walls with MI, to deteriorate. (C) 2004 by Excerpta Medica, Inc.
  • Critical scale invariance in a healthy human heart rate, K Kiyono, ZR Struzik, N Aoyagi, S Sakata, J Hayano, Y Yamamoto, PHYSICAL REVIEW LETTERS, 93, (17) ,   2004年10月, 査読有り, We demonstrate the robust scale-invariance in the probability density function (PDF) of detrended healthy human heart rate increments, which is preserved not only in a quiescent condition, but also in a dynamic state where the mean level of the heart rate is dramatically changing. This scale-independent and fractal structure is markedly different from the scale-dependent PDF evolution observed in a turbulentlike, cascade heart rate model. These results strongly support the view that a healthy human heart rate is controlled to converge continually to a critical state.
  • Bed rest attenuates sympathetic and pressor responses to isometric exercise in antigravity leg muscles in humans, A Kamiya, D Michikami, T Shiozawa, S Iwase, J Hayano, T Kawada, K Sunagawa, T Mano, AMERICAN JOURNAL OF PHYSIOLOGY-REGULATORY INTEGRATIVE AND COMPARATIVE PHYSIOLOGY, 286, (5) R844 - R850,   2004年05月, 査読有り, Although spaceflight and bed rest are known to cause muscular atrophy in the antigravity muscles of the legs, the changes in sympathetic and cardiovascular responses to exercises using the atrophied muscles remain unknown. We hypothesized that bed rest would augment sympathetic responses to isometric exercise using antigravity leg muscles in humans. Ten healthy male volunteers were subjected to 14-day 6degrees head-down bed rest. Before and after bed rest, they performed isometric exercises using leg (plantar flexion) and forearm (handgrip) muscles, followed by 2-min postexercise muscle ischemia (PEMI) that continues to stimulate the muscle metaboreflex. These exercises were sustained to fatigue. We measured muscle sympathetic nerve activity (MSNA) in the contralateral resting leg by microneurography. In both pre- and post-bed-rest exercise tests, exercise intensities were set at 30 and 70% of the maximum voluntary force measured before bed rest. Bed rest attenuated the increase in MSNA in response to fatiguing plantar flexion by similar to70% at both exercise intensities (both P < 0.05 vs. before bed rest) and reduced the maximal voluntary force of plantar flexion by 15%. In contrast, bed rest did not alter the increase in MSNA response to fatiguing handgrip and had no effects on the maximal voluntary force of handgrip. Although PEMI sustained MSNA activation before bed rest in all trials, bed rest entirely eliminated the PEMI-induced increase in MSNA in leg exercises but partially attenuated it in forearm exercises. These results do not support our hypothesis but indicate that bed rest causes a reduction in isometric exercise-induced sympathetic activation in (probably atrophied) antigravity leg muscles.
  • Effects of daily stress on autonomic cardiac control in patients with coronary artery disease, SL Bacon, LL Watkins, M Babyak, A Sherwood, J Hayano, AL Hinderliter, R Waugh, JA Blumenthal, AMERICAN JOURNAL OF CARDIOLOGY, 93, (10) 1292 - 1294,   2004年05月, 査読有り, Emotional stress has been implicated in the development and progression of coronary artery disease, with 1 proposed causal pathway being changes in cardiac autonomic tone. One hundred thirty-five patients with coronary artery disease underwent 48 hours of ambulatory electrocardiographic monitoring and completed activity and mood diaries every 20 minutes while awake. Random-effects model analyses associated higher levels of negative emotions (e.g., anger, stress, sadness) with decreases in high- and low-frequency power, whereas higher levels of positive emotion were related to an increase in low-frequency power, independent of age, posture, and medications. (C) 2004 by Excerpta Medica, Inc.
  • Respiratory sinus arrhythmia - Why does the heartbeat synchronize with respiratory rhythm?, F Yasuma, J Hayano, CHEST, 125, (2) 683 - 690,   2004年02月, 査読有り, Respiratory sinus arrhythmia (RSA) is heart rate variability in synchrony with respiration, by which the R-R interval on an ECG is shortened during inspiration and prolonged during expiration. Although RSA has been used as an index of cardiac vagal function, it is also a physiologic phenomenon reflecting respiratory-circulatory interactions universally observed among vertebrates. Previous studies have shown that the efficiency of pulmonary gas exchange is improved by RSA, suggesting that RSA may play an active physiologic role. The matched timing of alveolar ventilation and its perfusion with RSA within each respiratory cycle could save energy expenditure by suppressing unnecessary heartbeats during expiration and ineffective ventilation during the ebb of perfusion. Furthermore, evidence has accumulated of a possible dissociation between RSA and vagal control of that heart rate, suggesting differential controls between the respiratory modulation of cardiac vagal outflow and cardiac vagal tone. RSA or heart rate variability in synchrony with respiration is a biological phenomenon, which may have a positive influence on gas exchange at the level of the lung via efficient ventilation/perfusion matching.
  • alpha-Adrenergic vascular responsiveness to sympathetic nerve activity is intact after head-down bed rest in humans, A Kamiya, D Michikami, S Iwase, J Hayano, T Kawada, M Sugimachi, K Sunagawa, AMERICAN JOURNAL OF PHYSIOLOGY-REGULATORY INTEGRATIVE AND COMPARATIVE PHYSIOLOGY, 286, (1) R151 - R157,   2004年01月, 査読有り, Spaceflight and its ground-based simulation model, 6degrees head-down bed rest (HDBR), cause cardiovascular deconditioning in humans. Because sympathetic vasoconstriction plays a very important role in circulation, we examined whether HDBR impairs alpha-adrenergic vascular responsiveness to sympathetic nerve activity. We subjected eight healthy volunteers to 14 days of HDBR and before and after HDBR measured calf muscle sympathetic nerve activity (MSNA; microneurography) and calf blood flow (venous occlusion plethysmography) during sympathoexcitatory stimulation (rhythmic handgrip exercise). HDBR did not change the increase in total MSNA (P = 0.97) or the decrease in calf vascular conductance (P = 0.32) during exercise, but it did augment the increase in calf vascular resistance (P = 0.0011). HDBR augmented the transduction gain from total MSNA into calf vascular resistance, assessed as the least squares linear regression slope of vascular resistance on total MSNA (0.05 +/- 0.02 before HDBR, 0.20 +/- 0.06 U.min(-1).burst(-1) after HDBR, P = 0.0075), but did not change the transduction gain into calf vascular conductance (P = 0.41). Our data indicate that alpha-adrenergic vascular responsiveness to sympathetic nerve activity is preserved in the supine position after HDBR in humans.
  • Depression as a risk factor for mortality after acute myocardial infarction, RM Carney, JA Blumenthal, D Catellier, KE Freedland, LF Berkman, LL Watkins, SM Czajkowski, J Hayano, AS Jaffe, AMERICAN JOURNAL OF CARDIOLOGY, 92, (11) 1277 - 1281,   2003年12月, 査読有り, The ENRICHD clinical trial, which compared an intervention for depression and social isolation to usual care, failed to decrease the rate of mortality and recurrent acute myocardial infarction (AMI) in post-AMI patients. One explanation for this is that depression was not associated with increased mortality in these patients. The purpose of this study was to determine if depression was associated with an increased risk of mortality in a subsample of the ENRICHD trial's depressed patients compared with a group of nondepressed patients recruited for an ancillary study. Three hundred fifty-eight depressed patients with an acute AMI from the ENRICHD clinical trial and 408 nondepressed patients who met the ENRICHD medical inclusion criteria were followed for up to 30 months. There-were 47 deaths (6.1%) and 57 nonfatal AMIs (7.4%). After adjusting for other risk factors, depressed patients were at higher risk for all-cause mortality (hazard ratio 2.4, 95% confidence interval 1.2 to 4.7) but not for nonfatal recurrent infarction (hazard ratio 1.2, 95% confidence interval 0.7 to 2.0) compared with nondepressed patients. In conclusion, depression was an independent risk factor for death after AMI, but it did not have a significant effect on mortality until nearly 12 months after the acute event, nor did it predict nonfatal recurrent infarction. (C) 2003 by Excerpta Medica, Inc.
  • The role of apically directed intraventricular isovolumic relaxation flow in speeding early diastolic left ventricular filling, A Yanada, N Ohte, H Narita, S Akita, H Miyabe, N Takada, T Goto, S Mukai, J Hayano, G Kimura, JOURNAL OF THE AMERICAN SOCIETY OF ECHOCARDIOGRAPHY, 16, (12) 1226 - 1230,   2003年12月, 査読有り, Left ventricular (LV) systolic performance has been acknowledged to have a close relation to LV early diastolic filling and LV relaxation. However, the mechanism showing how good LV systolic function enhances the LV early diastolic filling has not been fully elucidated from the viewpoint of intraventricular flow dynamics. Thus, we investigated this issue in 82 patients with suggested coronary artery disease who underwent cardiac catheterization. Apically directed intraventricular isovolumic relaxation flow (IRF) and the propagation velocity of early diastolic filling flow were measured using pulsed and color Doppler echocardiography. LV ejection fraction and LV relaxation time constant tau were obtained in cardiac catheterization. As we were not able to measure the IRF velocity less than 14 cm/s that was limited by a Doppler low-cut filter, we analyzed the data collected from 78 patients with measurable IRF velocity. The IRF velocity significantly correlated with LV ejection fraction (r = 0.74, P < .001) and with LV relaxation time constant T (r = -0.31, P < .01). The propagation velocity of early diastolic filling flow significantly correlated with the IRF velocity (r = 0.73, P < .001) and also significantly correlated with LV ejection fraction (r = 0.70, P < .001). Good LV systolic performance augments LV early diastolic filling directly, mediated by IRF. A faster IRF velocity may play a role in delivering good LV systolic performance to LV early diastolic filling.
  • Rhythm-independent feature of heart rate dynamics common to atrial fibrillation and sinus rhythm in patients with paroxysmal atrial fibrillation., Sato K, Yamasaki F, Furuno T, Hamada T, Mukai S, Hayano J, Sugiura T, Doi Y, Journal of cardiology, 42, (6) 269 - 276,   2003年12月, 査読有り
  • Reverse redistribution phenomenon on rest (99m)Tc-tetrofosmin myocardial single photon emission computed tomography involves impaired left ventricular contraction in patients with acute myocardial infarction., Kurokawa K, Ohte N, Miyabe H, Akita S, Yajima K, Hayano J, Kimura G, Circulation journal : official journal of the Japanese Circulation Society, 67, (10) 830 - 834,   2003年10月, 査読有り
  • Pathophysiology of orthostatic hypotension after bed rest: paradoxical sympathetic withdrawal, A Kamiya, D Michikami, Q Fu, S Iwase, J Hayano, T Kawada, T Mano, K Sunagawa, AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY, 285, (3) H1158 - H1167,   2003年09月, 査読有り, Although orthostatic hypotension is a common clinical syndrome after spaceflight and its ground-based simulation model, 6degrees head-down bed rest (HDBR), the pathophysiology remains unclear. The authors' hypothesis that a decrease in sympathetic nerve activity is the major pathophysiology underlying orthostatic hypotension after HDBR was tested in a study involving 14-day HDBR in 22 healthy subjects who showed no orthostatic hypotension during 15-min 60degrees head-up tilt test ( HUT) at baseline. After HDBR, 10 of 22 subjects demonstrated orthostatic hypotension during 60degrees HUT. In subjects with orthostatic hypotension, total activity of muscle sympathetic nerve activity (MSNA) increased less during the first minute of 60degrees HUT after HDBR (314% of resting supine activity) than before HDBR (523% of resting supine activity, P < 0.05) despite HDBR-induced reduction in plasma volume (13% of plasma volume before HDBR). The postural increase in total MSNA continued during several more minutes of 60&DEG; HUT while arterial pressure was maintained. Thereafter, however, total MSNA was paradoxically suppressed by 104% of the resting supine level at the last minute of HUT ( P < 0.05 vs. earlier 60degrees HUT periods). The suppression of total MSNA was accompanied by a 22 +/- 4-mmHg decrease in mean blood pressure (systolic blood pressure < 80 mmHg). In contrast, orthostatic activation of total MSNA was preserved throughout 60&DEG; HUT in subjects who did not develop orthostatic hypotension. These data support the hypothesis that a decrease in sympathetic nerve activity is the major pathophysiological factor underlying orthostatic hypotension after HDBR. It appears that the diminished sympathetic activity, in combination with other factors associated with HDBR ( e. g., hypovolemia), may predispose some individuals to postural hypotension.
  • Prognostic value of nonlinear heart rate dynamics in hemodialysis patients with coronary artery disease, H Fukuta, J Hayano, S Ishihara, S Sakata, N Ohte, H Takahashi, M Yokoya, T Toriyama, H Kawahara, K Yajima, K Kobayashi, G Kimura, KIDNEY INTERNATIONAL, 64, (2) 641 - 648,   2003年08月, 査読有り, Background. Although altered nonlinear heart rate dynamics predicts death in patients with coronary artery disease (CAD), its prognostic value in chronic hemodialysis patients with CAD is unknown. Methods. We analyzed 24-hour electrocardiogram for nonlinear heart rate dynamics and heart rate variability in a retrospective cohort of 81 chronic hemodialysis patients with CAD. Results. During a follow-up period of 31 +/- 20 months, 19 cardiac and 8 noncardiac deaths were observed. Cox hazards model, including diabetes, left ventricular ejection fraction, and the number of diseased coronary arteries, revealed that abnormal alpha(2) (defined as both increase and decrease in alpha(2) because of its J curve relationship with cardiac mortality), decreased approximate entropy and decreased heart rate variability (triangular index and ultra-low frequency power) were significant and independent predictors of cardiac death. No significant and independent predictive power for noncardiac death was observed in either the heart rate dynamics or the heart rate variability measures. The predictive power of alpha(2) and approximate entropy was independent of that of triangular index and ultra-low frequency power. Combinations of two categories of measures improved the predictive accuracy; overall accuracy of approximate entropy + ultra-low frequency power for cardiac death was 87%. Conclusion. Altered nonlinear heart rate dynamics are independent predictors of cardiac death in chronic hemodialysis patients with CAD and their combinations with decreased heart rate variability provide clinically useful markers for risk stratification.
  • Clinical usefulness of carotid arterial wave intensity in assessing left ventricular systolic and early diastolic performance, N Ohte, H Narita, M Sugawara, K Niki, T Okada, A Harada, J Hayano, G Kimura, HEART AND VESSELS, 18, (3) 107 - 111,   2003年07月, 査読有り, Wave intensity (WI) is a novel hemodynamic index, which is defined as (dP/dt).(dU/dt) at any site of the circulation, where dP/dt and dU/dt are the derivatives of blood pressure and velocity with respect to time, respectively. However, the pathophysiological meanings of this index have not been fully elucidated in the clinical setting. Accordingly, we investigated this issue in 64 patients who underwent invasive evaluation of left ventricular (LV) function. WI was obtained at the right carotid artery using a color Doppler system for blood velocity measurement combined with an echo-tracking method for detecting vessel diameter changes. The vessel diameter changes were automatically converted to pressure waveforms by calibrating its peak and minimum values by systolic and diastolic brachial blood pressures. The WI of the patients showed two sharp positive peaks. The first peak was found at the very early phase of LV ejection, while the second peak was observed near end-ejection. The magnitude of the first peak of WI significantly correlated with the maximum rate of LV pressure rise (LV max. dP/dt) (r = 0.74, P < 0.001). The amplitude of the second peak of WI significantly correlated with the time constant of LV relaxation (r = -0.77, P < 0.001). The amplitude of the second peak was significantly greater in patients with the inertia force of late systolic aortic flow than in those without the inertia force (3 080 +/- 1741 vs 1890 +/- 1291 mmHg M s(-3), p < 0.01). These findings demonstrate that the magnitude of the first peak of WI reflects LV contractile performance, and the amplitude of the second peak of WI is determined by LV behavior during the period from late systole to isovolumic relaxation. WI is a noninvasively obtained, clinically useful parameter for the evaluation of LV systolic and early diastolic performance at the same time.
  • Heat stress modifies human baroreflex function independently of heat-induced hypovolemia, A Kamiya, D Michikami, J Hayano, K Sunagawa, JAPANESE JOURNAL OF PHYSIOLOGY, 53, (3) 215 - 222,   2003年06月, 査読有り, Since human thermoregulatory heat loss responses, cutaneous vasodilation and sweating, cause hypovolemia, they should resultantly stimulate human baroreflexes. However, it is possible that the thermoregulatory system directly interacts with the baroreflex system through central neural connections independently of the heat-induced hypovolemia. We hypothesized that heat stress modifies the baroreflex control of sympathetic nerve activity independently of heat-induced hypovolemia in humans. We made whole-body heating with tube-lined suits perfused with warm water (46-47degreesC) on 10 healthy male subjects. The heating increased skin and tympanic temperatures by 10.0 and 0.4degreesC, respectively. It increased resting total muscle sympathetic nerve activity (MSNA, microneurography) by 94+/-9% and decreased central venous pressure (CVP, dependent arm technique) by 2.6+/-0.9 mmHg. The heating increased arterial baroreflex gain by 193%, assessed as a response of MSNA to a decrease in diastolic arterial pressure during Valsalva's maneuver, but it did not change threshold arterial pressure for MSNA activation. Although the heating did not change the cardiopulmonary baroreflex gain assessed as a response of MSNA to a change in estimated central venous pressure (CVP) during a 10degrees head-down and -up tilt test, it upwardly shifted the stimulus-response baroreflex relationship. These changes in baroreflex functions during heating were not restored by an intravenous infusion of warmed isotonic saline (37degreesC, 15 ml/kg) that restored the heat-induced reduction of CVP. Our results support our hypothesis that heat stress modifies the baroreflex control of MSNA independently of heat-induced hypovolemia in humans. Our results also suggest that the hyperthermal modification of baroreflex results from central neural interaction between thermoregulatory and baroreflex systems. [Japanese Journal of Physiology, 53, 215-222, 2003].
  • Hypothesis: respiratory sinus arrhythmia is an intrinsic resting function of cardiopulmonary system, J Hayano, F Yasuma, CARDIOVASCULAR RESEARCH, 58, (1) 1 - 9,   2003年04月, 査読有り, A hypothesis is presented that explains the physiological reasons why the magnitude of respiratory sinus arrhythmia (RSA) appears to correlate with cardiac vagal tone. The hypothesis is that RSA is an intrinsic resting function of the cardiopulmonary system. Although RSA is mediated by respiratory modulation of cardiac vagal outflow and its magnitude is used as an index of cardiac vagal activity, RSA itself reflects cardiorespiratory interaction. RSA is universally observed among vertebrates throughout the evolution, suggesting that it may bear an intrinsic physiological role. Recent studies have shown that RSA improves pulmonary gas exchange efficiency by matching alveolar ventilation and capillary perfusion throughout respiration cycle.. This suggests that in resting animals and humans, RSA could save cardiac and respiratory energy by suppressing unnecessary heartbeats during expiration and ineffective ventilation during waning phases of perfusion. Furthermore, evidence is accumulating for possible dissociation between the magnitude of RSA and vagal control of heart rate, suggesting separated and independent regulations for respiratory modulation of cardiac vagal outflow from those for cardiac vagal tone. By our hypothesis, the apparent associations between RSA and cardiac vagal tone are explained as indirect consequences; i.e., whenever the cardiac vagal tone changes in response to the resting level of the cardiopulmonary system, RSA appears to change parallel to it. Our hypothesis seems more consistent with both physiological and clinical evidence about RSA than that presuming RSA is an index of cardiac vagal activity. (C) 2003 European Society of Cardiology. Published by Elsevier Science B.V. All rights reserved.
  • Prognostic value of heart rate variability in patients with end-stage renal disease on chronic haemodialysis., Fukuta H, Hayano J, Ishihara S, Sakata S, Mukai S, Ohte N, Ojika K, Yagi K, Matsumoto H, Sohmiya S, Kimura G, Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association, 18, (2) 318 - 325,   2003年02月, 査読有り
  • Coronary-prone behavior among Japanese men., Hori R, Hayano J, Monou H, Kimura K, Tsuboi H, Kamiya T, Kobayashi F, Type A Behavior, Pattern Conference, Circulation journal : official journal of the Japanese Circulation Society, 67, (2) 129 - 132,   2003年02月, 査読有り
  • Responses of heart rate and vagus tone to treadmill walking on land and in water in healthy older adults, T Takahashi, A Okada, J Hayano, N Takeshima, JOURNAL OF AGING AND PHYSICAL ACTIVITY, 11, (1) 18 - 26,   2003年01月, To determine water immersion's effect on heart rate (HR) and vagal tone, the authors examined HR and high-frequency R-R-interval variability in 7 healthy older adults at rest and during treadmill walking, starting at 3.0 km/hr and increasing 0.5 km/hr every 3 min at a 5% grade to exhaustion. Participants performed the test on land and then immersed in water to the xiphoid. HR at rest did not differ between water and land. During walking at 3.0 km/min, HR was significantly lower in water than on land, whereas at 4.5 and 5.0 km/min it was significantly higher (each p < .05). Peak HR at exhaustion was not significantly different between water and land. High-frequency amplitudes at rest and during exercise in water were not significantly different from those on land. The results suggest that resting vagus tone and vagal changes in response to walking exercise in elderly adults are not greatly affected by water immersion.
  • Blood pressure and heart rate variability in taxi drivers on long duty schedules, F Kobayashi, T Watanabe, M Watanabe, Y Akamatsu, T Tomita, T Nakane, H Furui, K Takeuchi, A Okada, R Ohashi, J Hayano, JOURNAL OF OCCUPATIONAL HEALTH, 44, (4) 214 - 220,   2002年07月, Objective-To clarify the mechanisms of excessive risk of cardiovascular disease among taxi drivers, the effects of taxi driving with long work hours on taxi drivers' blood pressure and heart rate variability were examined. Methods -We measured the physical activity level, ambulatory blood pressure, and Holter ECG in 34 healthy middle-aged male taxi drivers over one work day and the two following non-work days. The subjects worked for a 24-h period starting at 07:00, then rested from work for 48 h. Ambulatory blood pressure was recorded automatically at 30-min intervals over the 72-h period. Holter ECG records were also kept for the 72 h, and temporal changes in the R-R interval were analyzed by the complex demodulation method (CDM). The amplitude of the high frequency (HF) components (central frequency 0.30 Hz), and the ratio of low-frequency components (central frequency 0.09 Hz) to high-frequency components (L/H) was calculated. Results-Blood pressure during the work day was significantly higher than that during the non-work days, with a stronger effect in the hypertensive subjects. There were no significant overall differences in heart rate variability between the work day and the non-work days, but the temporal patterns of HF and L/H on the work day revealed a potent effect of reversed-phased circadian rhythm for work at night. Conclusions-Long duty taxi driving raises blood pressure and may increase cardiovascular risk as a result. The conflict between the circadian rhythms of autonomic nervous activity and work activity at night may also result in increased risk.
  • The mechanism of emergence and clinical significance of apically directed intraventricular flow during isovolumic relaxation, N Ohte, H Narita, S Akita, K Kurokawa, J Hayano, M Sugawara, G Kimura, JOURNAL OF THE AMERICAN SOCIETY OF ECHOCARDIOGRAPHY, 15, (7) 715 - 722,   2002年07月, 査読有り, The mechanism of emergence and the clinical significance of apically directed intraventricular flow during isovolumic relaxation were investigated. The relation between the spatial distribution of the flow and left ventricular (LV) apical wall motion abnormality, as well as LV performance, was studied in 97 patients who underwent cardiac catheterization for evaluation of chest pain. According to the distribution of the flow, the patients were classified into the following 3 groups: flow observed in the whole area between the tip of the papillary muscle and the apex (spread flow) (n = 38), flow observed in the same area that did not fill the whole area (localized flow) (n = 15), and no apparent flow observed in the area (without flow) (n = 44). An absence of flow disclosed apical. asynergy with a sensitivity of 97% and specificity of 87%. The time constant of LV relaxation was significantly shorter in patients with spread flow than in those without flow. A significant difference was also observed in end-systolic volume index (18.8 +/- 6.8 vs 30.9 +/- 7.7 vs 42.3 +/- 20.2 mL/m(2), spread flow < localized flow < without flow, P < .05) among the 3 groups. The propagation velocity of LV early diastolic filling flow was significantly greater in patients with spread flow (47.0 +/- 8.3 cm/s) than in those with localized flow (30.7 +/- 7.8 cm/s) or without flow (28.6 +/- 7.8 cm/s) (P < .001). These findings indicate that the greater magnitude of LV elastic recoil and the faster LV relaxation in patients without LV apical asynergy produce apically directed intraventricular flow during isovolumic relaxation, enhancing the speed of LV early diastolic filling. Apically directed intraventricular flow during isovolumic relaxation may play an important role as a mediator of better LV systolic performance and LV relaxation to LV early diastolic filling. Absence of apically directed intraventricular flow during isovolumic relaxation is a manifestation of LV apical asynergy and global LV dysfunction from end systole to early diastole.
  • Myocardial oxidative metabolism in remote normal regions in the left ventricles with remodeling after myocardial infarction: Effect of beta-adrenoceptor blockers, N Ohte, K Kurokawa, A Iida, H Narita, S Akita, K Yajima, H Miyabe, J Hayano, G Kimura, JOURNAL OF NUCLEAR MEDICINE, 43, (6) 780 - 785,   2002年06月, 査読有り, In patients with myocardial infarction (MI), an expansion of the remote normal regions of the left ventricle is often observed. However, the characteristics of such regions are not fully understood. Thus, we investigated this issue from the standpoint of myocardial oxidative metabolism using C-11-acetate PET. Methods: In 33 patients with recent MI (24 not receiving beta-blockers, 9 receiving beta-blockers) and 12 age-matched normal control subjects, C-11-acetate dynamic myocardial PET scanning was performed at rest. Time-activity curves of C-11-acetate in 5-7 regions of interest (ROIs) on the midventricular transaxial image in each subject were generated, and the clearance rate constant (K-mono) in each ROI was calculated by monoexponential fitting as an index of myocardial oxidative metabolism. The left ventricular (LV) end-diastolic volume index as an index of LV remodeling and the heart rate . pressure product were obtained in all subjects. Results: The LV end-diastolic volume index was significantly larger in patients with MI without beta-blockers than in normal control subjects (101 +/- 22.5 vs. 61.6 +/- 12.8 mL . m(-2); P < 0.001). There was no significant difference in the heart rate . pressure product between the patients with MI without 3-blockers and the normal control subjects (8,229 +/- 1,503 vs. 8,311 +/- 1,311 mm Hg . min(-1)). The K-mono in remote normal regions was significantly greater in patients with MI without beta-blockers even when compared with the highest K-mono on the anteroseptal wall of the left ventricle in normal control subjects (0.078 +/-t 0.022 vs. 0.065 +/- 0.007 min(-1); P < 0.01). In contrast, the heart rate . pressure product (6,911 +/- 1,135 mm Hg . min(-1)) and the K-mono (0.054 +/- 0.009 min(-1)) in remote normal regions were significantly less in patients with beta-blockers than in those without beta-blockers (P < 0.001). No significant difference in the LV end-diastolic volume index was found between the MI patients with and without beta-blockers. Multivariate regression analysis showed that beta-blockers significantly and directly decreased the K-mono in remote normal regions after adjusting the effect of the heart rate - pressure product, although the prime determinant of the K-mono in such regions was the heart rate - pressure product. Conclusion: Myocardial oxidative metabolism in remote normal regions is accelerated in the left ventricles with remodeling after acute MI. Therapy using beta-blockers normalizes the myocardial oxidative metabolism in such regions through the reduction of the heart rate - pressure product and their direct effect on the myocardium.
  • Respiratory sinus arrhythmia : Mechanisms and implications, Fumihiko Yasuma, Jun Ichiro Hayano, Respiration and Circulation, 50, 283 - 289,   2002年03月01日
  • Direct effect of Pa(CO2) on respiratory sinus arrhythmia in conscious humans., Sasano N, Vesely AE, Hayano J, Sasano H, Somogyi R, Preiss D, Miyasaka K, Katsuya H, Iscoe S, Fisher JA, American journal of physiology. Heart and circulatory physiology, 282, (3) H973 - 6,   2002年03月, 査読有り
  • Water-based exercise improves health-related aspects of fitness in older women, N Takeshima, ME Rogers, E Watanabe, WF Brechue, A Okada, T Yamada, MM Islam, J Hayano, MEDICINE AND SCIENCE IN SPORTS AND EXERCISE, 34, (3) 544 - 551,   2002年03月, 査読有り, Purpose: The purpose of this study was to determine the physiological responses of elderly women to a well-rounded exercise program performed in water (WEX). Methods: The participants (60-75 yr of age) were randomly divided into a training (TR) group (N = 15) and a control group (N = 15). The TR group participated in a 12-wk supervised WEX program, 70 min.day(-1), 3 d.wk(-1). The WEX consisted of 20 min of warm-up and stretching exercise, 10 min of resistance exercise, 30 min of endurance-type exercise (walking and dancing), and 10 min of cool-down exercise. Results: The WEX led to an increase (P < 0.05) in peak (V) over dot O-2 (12%) and (V) over dot O-2 at lactate threshold (20%). Muscular strength evaluated by a hydraulic resistance machine increased significantly at resistance dial setting 8 (slow) for knee extension (8%), knee flexion (13%), chest press (7%) and pull (11%), shoulder press (4%) and pull (6%), and back extension (6%). Vertical jump (9%), side-stepping agility (22%), trunk extension (11%), and FEV1.0 (7%) also increased significantly. There was a significant decrease in skin-fold thickness (-8%), low-density lipoprotein (LDL) cholesterol (-17%), and total cholesterol There were no significant changes in these variables in the control group. Conclusion: These results indicate that WEX elicits significant improvements in cardiorespiratory fitness, muscular strength, body fat, and total cholesterol in older adult women. Water-based exercise appears to be a very safe and beneficial mode of exercise that can be performed as part of a well-rounded exercise program.
  • Striking effect of left ventricular high filling pressure with mitral regurgitation on mitral annular velocity during early diastole. A study using colour M-mode tissue Doppler imaging., Ohte N, Narita H, Akita S, Kurokawa K, Hayano J, Kimura G, European journal of echocardiography : the journal of the Working Group on Echocardiography of the European Society of Cardiology, 3, (1) 52 - 58,   2002年03月, 査読有り
  • Circadian rhythm of atrioventricular conduction predicts long-term survival in patients with chronic atrial fibrillation, J Hayano, S Ishihara, H Fukuta, S Sakata, S Mukai, N Ohte, G Kimura, CHRONOBIOLOGY INTERNATIONAL, 19, (3) 633 - 648,   2002年, 査読有り, The R-R interval of the electrocardiogram during atrial fibrillation (AF) appears absolutely irregular. However, the Poincare plot of the R-R interval reveals a sector shape of distribution that is unique to AF. Furthermore, the height of lower envelope (LE1.0) of the distribution and the degree of scatter above the envelope (scattering index) may reflect the refractoriness and concealment of atrioventricular (AV) conduction. respectively. We previously observed that both the LE1.0 and scattering index show clear circadian rhythms in patients with chronic AF and that the rhythms are blunted in those with congestive heart failure and chronic AF. In the present study, we examined if the blunted circadian rhythm of the AV conduction has prognostic value in patients with chronic AF. We studied a retrospective cohort of 120 patients who underwent 24h Holter monitoring at baseline. During an observation period of 33 +/- 16 mon. there were 25 deaths (21%) including 13 cardiac and 8 stroke deaths. All patients showed significant circadian rhythms in both LE1.0 and scattering index with acrophases occurring at night; however, patients dying subsequently from cardiac causes, but not those from fatal stroke were blunted in the circadian rhythms (the amplitudes were < 55% of those in surviving patients). Furthermore, the reduced circadian amplitude of scattering index was an increased risk for cardiac death even after adjustment of coexisting cardiovascular risks [adjusted relative risk (95% confidence interval) per 1-SD decrement, 4.24 (1.54- 11.6)]. When patients were divided by the circadian amplitude of the scattering index of 36.5 msec (mean minus 1-SD), the 5yr cardiac mortality below and above the cutoff was 57 and 6%, respectively (log-rank test, p < 0.001). We conclude that the blunted circadian rhythm of AV conduction is an independent risk for cardiac death in patients with chronic AF.
  • Influence of cool-down exercise on autonomic control of heart rate during recovery from dynamic exercise., Takahashi T, Okada A, Hayano J, Tamura T, Frontiers of medical and biological engineering : the international journal of the Japan Society of Medical Electronics and Biological Engineering, 11, (4) 249 - 259,   2002年, 査読有り
  • Postural response of low-frequency component of heart rate variability is an increased risk for mortality in patients with coronary artery disease, J Hayano, S Mukai, H Fukuta, S Sakata, N Ohte, G Kimura, CHEST, 120, (6) 1942 - 1952,   2001年12月, 査読有り, Study objectives: We examined whether autonomic functions assessed by heart cute variability (HRV) during standardized head-up tilt testing (HUTT) predict risk for death In stable patients with coronary artery disease (CAD). Design and setting: Retrospective cohort study in medium-sized university general hospital. Measurements and results: In a cohort of 250 patients with CAD who were undergoing elective coronary angiography, we analyzed HRV during standardized HUTT under paced breathing with discontinuation of treatment with all medications. During a subsequent mean follow-up period of 99 months, there were 13 cardiac deaths and 12? noncardiac deaths. Cox regression analysis adjusted for cardiovascular asks revealed that increased postural change (supine to upright) in the power of low-frequency component (LF) power predicted an increased risk for cardiac death (relative risk [per 1-ln ms(2) increment], 4.36; 95% confidence interval, 1.64 to 11.6), while neither the high-frequency component nor its response to HUTT predicted any form of death. When the patients reeve trichotomized by the level of postural LF change (large drop, less than or equal to - 0.6 In[ms(2)];small drop and rise, > 0 In[ms]), the three groups did not differ in terms of clinical features or CAD severity at baseline or coronary interventions during the follow-up period; however, the 8-year cardiac mortality rates were 0%, 6%, and 12%, respectively (p = 0.008 [log rank test]). Additionally, the difference was enhanced when analyzed excluding 64 patients who lout been treated with a beta -blocker during the follow-up period (0%, 7%, and 15%, respectivcly; p = 0.006 [log rank test]). Conclusions: The postural response of HRV predicts the risk for death in patients with CAD. Postural LF increase (LF rise), in particular, is an independent ask factor for cardiac death.
  • Striking effect of left ventricular systolic performance on propagation velocity of left ventricular early diastolic filling flow, N Ohte, H Narita, S Akita, K Kurokawa, J Hayano, G Kimura, JOURNAL OF THE AMERICAN SOCIETY OF ECHOCARDIOGRAPHY, 14, (11) 1070 - 1074,   2001年11月, 査読有り, Propagation velocity of left ventricular (IV) early diastolic filling flow (PVE) has been acknowledged as a useful parameter for IV early diastolic performance; however, the effect of IV systolic performance on PVE is not fully understood. Thus the purpose of this study was to investigate such an effect. Propagation of IV early diastolic filling flow was visualized by M-mode color Doppler imaging, and the slopes of the peak velocity tracings were measured as PVE in 150 patients who underwent coronary angiography. In cardiac catheterization, mean pulmonary capillary wedge pressure, time constant tau of IV pressure decay, IV end-systolic volume index, and IV ejection fraction were obtained. In univariate regression analysis, PVE significantly correlated with IV end-systolic volume index (r = -0.68, P < .001), LV ejection fraction (r = 0.66, P < .001), and time constant tau (r = -0.52, P < .001). in multivariate regressionanalysis, PVE was regressed by the IV end-systolic volume index, tau, and mean pulmonary capillary wedge pressure. The contribution of each parameter to the variance of the PVE was 46%, 3%, and 2%, respectively. A break-point linear regression analysis showed that the relation between the IV end-systolic volume index and PVE was much better characterized by a broken line than a straight line. The broken line had a steeper slope in patients with IV end-systolic volume index less than or equal to 41 mL/m(2) than in those with > 41 mL/m(2). These findings suggest that PVE is determined mainly by IV systolic performance and partly by both IV relaxation and IV filling pressure. Left ventricular systolic performance may play a key role in generating a much faster PVE, especially in patients with relatively better IV systolic performance.
  • Differential effects of hypoxia and hypercapnia on respiratory sinus arrhythmia in conscious dogs., Yasuma F, Hirai M, Hayano JI, Japanese circulation journal, 65, (8) 738 - 742,   2001年08月, 査読有り
  • Augmentation of respiratory sinus arrhythmia in response to progressive hypercapnia in conscious dogs., Yasuma F, Hayano J, American journal of physiology. Heart and circulatory physiology, 280, (5) H2336 - 41,   2001年05月, 査読有り
  • Impact of acute hypoxia on heart rate and blood pressure variability in conscious dogs., Yasuma F, Hayano JI, American journal of physiology. Heart and circulatory physiology, 279, (5) H2344 - 9,   2000年11月, 査読有り
  • Effects of shift work on 24-hour ambulatory blood pressure and its variability among Japanese workers, T Ohira, T Tanigawa, H Iso, Y Odagiri, T Takamiya, T Shimomitsu, J Hayano, T Shimamoto, SCANDINAVIAN JOURNAL OF WORK ENVIRONMENT & HEALTH, 26, (5) 421 - 426,   2000年10月, 査読有り, Objectives This study examined the effects of rotating shift work on blood pressure in a comparison of ambulatory blood pressure and long-term changes in blood pressure between shift and day workers. Methods Ambulatory blood pressure was measured for 24-hour periods at an interval of 30 minutes for 27 shift workers and 26 day workers when they worked during the day. Blood pressure was compared between these 2 groups of workers for 4 time categories (awake, sleep, nonwork awake, and work periods). Their long-term blood pressures, recorded in annual surveys, were reviewed for long-term changes. These comparisons were adjusted for the effects of body mass index, alcohol intake, anger expression, and physical activity. Results On the average, sleep time was shorter and the anger-in (ie, anger suppressed) score was higher for the shift workers than for the day workers, but body mass index and alcohol intake did not differ between the 2 groups. Even after adjustment for these co-variables, the mean systolic blood pressure during the 24-hour, awake, and work periods were higher among the shift workers than among the day workers. The 24-hour standard deviations of the systolic blood pressures were also higher for the shift workers than for the day workers. Among the shift workers, but not among the day workers, a significant long-term increase was observed in systolic blood pressure measured in the annual surveys. Conclusions These results suggest that shift work may increase systolic blood pressure levels among Japanese men.
  • Exercise and weight loss reduce blood pressure in men and women with mild hypertension - Effects on cardiovascular, metabolic, and hemodynamic functioning, JA Blumenthal, A Sherwood, ECD Gullette, M Babyak, R Waugh, A Georgiades, LW Craighead, D Tweedy, M Feinglos, M Appelbaum, J Hayano, A Hinderliter, ARCHIVES OF INTERNAL MEDICINE, 160, (13) 1947 - 1958,   2000年07月, 査読有り, Background: Lifestyle modifications have been recommended as the initial treatment strategy for lowering high blood pressure (BP). However, evidence for the efficacy of exercise and weight loss in the management of high BP remains controversial. Methods: One hundred thirty-three sedentary, overweight men and women with unmedicated high normal BP or stage 1 to 2 hypertension were randomly assigned to aerobic exercise only; a behavioral weight management program, including exercise; or a waiting list control group. Before and following treatment, systolic and diastolic BPs were measured in the clinic, during daily life, and during exercise and mental stress testing. Hemodynamic measures and metabolic functioning also were assessed. Results: Although participants in both active treatment groups exhibited significant reductions in BP relative to controls, those in the weight management group generally had larger reductions. Weight management was associated with a 7-mm Hg systolic and a 5-mm Hg diastolic clinic BP reduction, compared with a 4-mm Hg systolic and diastolic BP reduction associated with aerobic exercise; the BP for controls did not change. Participants in both treatment groups also displayed reduced peripheral resistance and increased cardiac output compared with controls, with the greatest reductions in peripheral resistance in those in the weight management group. Weight management participants also exhibited significantly lower fasting and postprandial glucose and insulin levels than participants in the other groups. Conclusions: Although exercise alone was effective in reducing BP, the addition of a behavioral weight loss program enhanced this effect. Aerobic exercise combined with weight loss is recommended for the management of elevated BP in sedentary, overweight individuals.
  • Reduced ventricular response irregularity is associated with increased mortality in patients with chronic atrial fibrillation, A Yamada, J Hayano, S Sakata, A Okada, S Mukai, N Ohte, G Kimura, CIRCULATION, 102, (3) 300 - 306,   2000年07月, 査読有り, Background-Variations in the ventricular response interval (VRI) during atrial fibrillation (AF) may be reduced in patients with adverse clinical outcomes. The properties of VRI dynamics associated with prognosis remain undetermined. Methods and Results-In 107 patients with chronic AF (age, 64 +/- 9 years), we analyzed a 24-hour ambulatory ECG for VRI variability (SD, SD of successive differences, and SD of 5-minute averages) and VRI irregularity (Shannon entropy of histogram, symbolic dynamics, and approximate entropy of beat-to-beat and minute-to-minute fluctuations [ApEn(b-b) and ApEn(m-m)]). During a follow-up period of 33 +/- 16 months, 18 patients died (17%), 9 from cardiac causes, 7 from fatal strokes, and 2 from malignancies. Reductions in all VRI variability and irregularity measures were associated with an increased risk for cardiac death but not for fatal stroke. A significant association with cardiac death was also found for ejection fraction (relative risk, 1.10; 95% confidence interval [CI], 1.04 to 1.17, per 1% decrement) and ischemic AF (relative risk, 6.52; 95% CI, 1.62 to 26.3). After adjustment for these clinical variables, all irregularity measures except symbolic dynamics had predictive value (relative risks [95% CIs] per ISD decrement: Shannon entropy of histogram, 2.03 [1.14 to 3.61]; ApEn(b-b) 1.72 [1.14 to 2.60]; and ApEn(m-m), 1.90 [1.03 to 3.52]); however, the predictive power of variability measures was no longer significant. When the patients were stratified with the 33rd and 67th percentile values of ApEn(b-b) (1.83 and 1.94, respectively), the 5-year cardiac mortality rates for the upper, middle, and lower tertiles were 0%, 13%, and 43%, respectively (log-rank test, P = 0.04). Conclusions-Reduced VRI irregularity in a 24-hour ambulatory ECG has an independent prognostic value for cardiac mortality during long-term follow-up in patients with chronic AF.
  • Difference in human cardiovascular response between upright and supine recovery from upright cycle exercise, T Takahashi, A Okada, T Saitoh, J Hayano, Y Miyamoto, EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY, 81, (3) 233 - 239,   2000年02月, 査読有り, Cardiovascular responses were examined in seven healthy male subjects during 10 min of recovery in the upright or supine position following 5 min of upright cycle exercise at 80% peak oxygen uptake. An initial rapid decrease in heart rate (f(c)) during the early phase of recovery followed by much slower decrease was observed for both the upright and supine positions. The average f(c) at the 10th min of recovery was significantly lower (P < 0.05) in the supine position than in the upright position, while they were both significantly greater than the corresponding pre-exercise levels teach P < 0.05). Accordingly, the amplitude of the high frequency (HF) component of R-R interval variability (by spectrum analysis) in both positions was reduced with a decrease in mean R-R interval, the relationship being expressed by a regression line - mean R-R interval = 0.006 x HF amplitude + 0.570 (r = 0.905, n = 28, P < 0.001). These results would suggest that the slower reduction in f(c) following the initial rapid reduction in both positions is partly attributable to a retardation in the restoration of the activity of the cardiac parasympathetic nervous system. Post-exercise upright stroke volume (SV, by impedance cardiography) decreased gradually to just below the pre-exercise level, whereas post-exercise supine SV increased markedly to a level similar to that at rest before exercise. The resultant cardiac output ((Q over dot (c)) and the total peripheral vascular resistance (TPR) in the upright and supine positions returned gradually to their respective pre-exercise levels in the corresponding positions. At the 10th min of recovery, both average SV and (Q) over dot (c) were significantly greater teach P < 0.005) in the supine than in the upright position, while average TPR was significantly lower (P < 0.05) in the supine than in the upright position. In contrast, immediately after exercise, mean blood pressure dropped markedly in both the supine and upright positions, and their levels at the 10th min of recovery were similar. Therefore we concluded that arterial blood pressure is maintained relatively constant through various compensatory mechanisms associated with f(c), SV, (Q) over dot (c), and TPR during rest and recovery in different body positions.
  • A case of anorexia nervosa with hyperinsulinemia and severe hypoglycemia induced by elemental diet (Elental®), M. Okada, Y. Kamiya, Y. Kanno, J. Hayano, S. Ishihara, A. Okada, S. Takeuchi, M. Kawaguchi, Journal of the Japan Diabetes Society, 43, 373 - 377,   2000年01月01日
  • [Sodium sensitivity in essential hypertension]., Hayano J, Kimura G, Nihon rinsho. Japanese journal of clinical medicine, 58 Suppl 1, 388 - 391,   2000年01月, 査読有り
  • Differentiation of abnormal relaxation pattern with aging from abnormal relaxation pattern with coronary artery disease in transmitral flow with the use of tissue Doppler imaging of the mitral annulus, N Ohte, H Narita, T Hashimoto, J Hayano, S Akita, K Kurokawa, JOURNAL OF THE AMERICAN SOCIETY OF ECHOCARDIOGRAPHY, 12, (8) 629 - 635,   1999年08月, 査読有り, An abnormal relaxation pattern in transmitral now velocity waveforms has been observed in older healthy subjects as well as in patients with heart disease. Accordingly, we investigated whether the hemodynamic differences between patients with coronary artery disease (CAD) with an abnormal relaxation pattern in transmitral flow (ratio of E-wave to A-wave velocities < 1.0) and healthy older subjects with an abnormal relaxation pattern can be distinguished with the use of mitral annular velocity (MAV) during early diastole. We measured MAV in the longitudinal direction of the heart during early diastole by M-mode color tissue Doppler imaging in 24 patients with atypical chest pain (defined as healthy subjects in this study) and 70 patients with CAD who underwent cardiac catheterization. In all patients a time constant of left ventricular pressure decay (tau) and the left ventricular (LV) end-systolic volume index were also measured. Twenty-one healthy subjects and 59 patients with CAD had an abnormal relaxation pattern in their transmitral flow. The age, heart rate, mean blood pressure, and ratio of E-wave to A-wave velocities were not different between the two groups. However, the tau was longer and the LV end-systolic volume index was greater in patients who had an abnormal relaxation pattern with CAD than in healthy subjects with an abnormal relaxation pattern. The MAV during early diastole was lower in the former than in the latter (5.8 +/- 1.3 vs 9.8 +/- 1.9 cm/s, P < .001). Mitral annular velocity during early diastole by M-mode color tissue Doppler imaging can detect the differences in LV relaxation and LV systolic performance between the abnormal relaxation pattern with CAD and the physiologically abnormal relaxation pattern with aging, providing further information regarding the meaning of an LV abnormal relaxation pattern.
  • Effects of sympathetic nerve blockades on low-frequency oscillations of human earlobe skin blood flow, H Sasano, J Hayano, T Tsuda, H Katsuya, JOURNAL OF THE AUTONOMIC NERVOUS SYSTEM, 77, (1) 60 - 67,   1999年07月, 査読有り, Earlobe skin blood flow measured by laser Doppler flowmetry often shows low-frequency oscillations with a frequency around 0.1 Hz. We evaluated the effects of different sympathetic blocking techniques on the oscillations. Power spectrum of 5-min time series of beat-to-beat peak earlobe skin blood flow showed a distinct spectral peak at a frequency around 0.1 Hz (mean +/- SD, 0.107 +/- 0.016 Hz). The power of the spectral peak measured as coefficient of component variance (CCV) was diminished with total spinal anesthesia (TSA, n = 4) and cervicothoracic epidural anesthesia (CTEA, n = 4; P < 0.05 for both). The CCV was unchanged significantly with bilateral thoracic sympathetic ganglionic excision (TSGE, n = 5). Right stellate ganglion block (RSGB, n = 6) caused a trend towards an increase in the CCV on the right (blocked)-side (P = 0.072) but no change on the left (intact)-side. Cross-spectrum analysis revealed that the low-frequency oscillations were not coherent between the right- and left-side earlobes or with low-frequency oscillations in systolic blood pressure either before or after RSGB. TSA and CTEA are known to cause extensive sympathetic nerve blockade in a broad area, while TSGE and RSGB are known to cause local and partial sympathetic blockade. Our results suggest that although the low-frequency oscillations in earlobe skin blood flow may be mediated non-neurally, magnitude of the oscillations may be modified by sympathetic vasomotor tone. (C) 1999 Elsevier Science B.V. All rights reserved.
  • Aging and spectral characteristics of the nonharmonic component of 24-h heart rate variability., Sakata S, Hayano J, Mukai S, Okada A, Fujinami T, The American journal of physiology, 276, (6 Pt 2) R1724 - 31,   1999年06月, 査読有り
  • Prognostic value of heart rate variability during long-term follow-up in chronic haemodialysis patients with end-stage renal disease., Hayano J, Takahashi H, Toriyama T, Mukai S, Okada A, Sakata S, Yamada A, Ohte N, Kawahara H, Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association, 14, (6) 1480 - 1488,   1999年06月, 査読有り
  • The current situation of psychosomatic medicine in the United States of America, J. I. Hayano, Japanese Journal of Psychosomatic Medicine, 39, 29 - 34,   1999年01月01日, To depict the current trends of the psychosomatic medicine in the USA, the changes during the past decade in the membership of the American Psychosomatic Society (APS) and in the major topics of the papers published in the journal, Psychosomatic Medicine, were investigated. The majority of the APS members hold a degree of MD, about half are psychiatrists, but the society is changing with an increased frequency of new PhD psychologists. Major areas of interest include behavioral medicine, consultation-liaison, cardiovascular diseases and psychotherapy. Top 3 topics in the papers published in Psychosomatic Medicine during the past decade have been coronary artery diseases, depression and hypertension. Recently, however, panic disorder is gathering increasing attentions. The APS keeps its uniqueness by maintaining the broad membership spectrum and by staying responsive to the varied interests of the members. Psychosomatic medicine in the USA has been challenging the most important medical and social problems in each era with using the most modern techniques of researches, such as megatrials and evidence-based medicine, through which it has been gaining a high reputation from both medical and general societies.
  • Influence of body composition on electrocardiographic identification of left ventricular hypertrophy in adolescents, S Sugita, K Takada, J Hayano, CARDIOLOGY, 91, (2) 127 - 133,   1999年, 査読有り, We investigated the influence of body composition on electrocardiographic (ECG) detection of left ventricular (LV) hypertrophy in 894 high-school students, The percent body fat and LV mass were estimated by bioelectrical impedance and echocardiography, respectively, There was no significant difference in LV mass among subjects classified according to the percent body fat. The cutoff ECG amplitudes (RV5 and SV1+RV5) for detection of LV hypertrophy (LV mass greater than or equal to 90th percentile in both boys and girls) with 90% specificity were highest in the low-far group and lowest in the high-fat group, When the effects of the percent body fat on ECG amplitudes were taken into account, the sensitivity of the ECG for detection of LV hypertrophy improved from 32.7 to 38.2% in boys; however, no improvement was observed in girls (from 33.3 to 30.6%), Evaluation of the percent body fat may improve the efficacy of ECG detection of LV hypertrophy in adolescent boys, but the usefulness of this method may be limited in girls.
  • Is the blood flow in the left ventricle during the isovolumic relaxation period a useful parameter of left ventricular systolic and early diastolic performance?, N Ohte, H Narita, T Hashimoto, J Hayano, S Akita, K Kurokawa, CARDIOLOGY, 91, (3) 184 - 188,   1999年, 査読有り, Left ventricular (LV) early diastolic performance is determined by LV behavior in the late systole to early diastole and may relate to the physical potential of patients. Isovolumic relaxation flow (IRF) velocity was obtained by continuous Doppler echocardiography in the left ventricle from the apex in 26 patients with atypical chest pain and 63 patients with coronary artery disease (CAD) with or without prior myocardial infarction (MI) who underwent cardiac catheterization. In each patient, a time constant of LV relaxation (tau) was calculated from the LV pressure waves obtained by a catheter-tipped micromanometer. The LV end-systolic volume index was measured using contrast left ventriculography. IRF velocity in patients having CAD with prior MI (24.8 +/- 5.4 cm/s) was significantly less than in those with atypical chest pain (41.2 +/- 9.6 cm/s). It was also significantly less than in patients having CAD without prior MI (37.3 +/- 6.8 cm/s). IRF velocity significantly correlated with the time constant tau (r = -0.42, p < 0.001) and LV end-systolic volume index (r = -0.84, p < 0.001), This study indicates that IRF velocity obtained by continuous Doppler echocardiography in the left ventricle provides important information regarding LV systolic performance and early diastolic performance.
  • The relationship between R amplitude in lead V-5 (RV5) and left ventricular mass in the groups of adolescent subjects classified by body composition, S Sugita, K Takada, H Takada, M Nagashima, J Hayano, JAPANESE CIRCULATION JOURNAL-ENGLISH EDITION, 62, (12) 893 - 899,   1998年12月, 査読有り, How the amplitude of the R wave in lead V5 (RV5) of the ECG represents the left ventricular (LV) mass was investigated in 894 students aged 15 (boys: 545, girls: 349). The influence of body composition [ie, percentage of body fat (%fat)] was taken into consideration. A significant correlation was found between RV5 amplitude and LV mass for both genders. However, the relationship was stronger for boys than for girls. The students were then divided into 3 groups; that is, those at either the top or bottom 10th percentile (low or high-fat range) and the rest of the students (middle-fat range), depending on the % fat calculated by the bioelectrical impedance method. The significant correlation between RV5 and LV mass was found only for the 2 groups of boys whose percentage fat was in the low or middle-fat range. The correlation coefficients were 0.40 and 0.34, respectively. Moreover, in the boys' low-fat range, the RV5 of students whose LV mass was large (greater than or equal to 90th percentile), was significantly higher (p<0.01) than in the other ranges. Setting a particular cutoff point of RV5 in the low-fat range of boys improved sensitivity as well as specificity (20-30% better among all boys) for detecting large LV mass. These observations suggest that classification of subjects by body composition could be improve the reliability of ECG assessment for left ventricular hypertrophy, although the gender and number of subjects in whom improvement is expected are limited.
  • Complex demodulation of cardiorespiratory dynamics preceding vasovagal syncope, LA Lipsitz, J Hayano, S Sakata, A Okada, RJ Morin, CIRCULATION, 98, (10) 977 - 983,   1998年09月, 査読有り, Background-The dynamic autonomic processes leading to vasovagal syncope are poorly understood. Methods and Results-We used complex demodulation to continuously assess changes in respiration, R-R interval, and arterial pressure (blood pressure) variability during 60 degree head-up tilt in 25 healthy subjects with tilt-induced vasovagal syncope and 25 age-matched nonsyncopal control subjects. Coherence and transfer function analyses were used to examine the relation between respiration and R-R interval variability before syncope, Baseline blood pressure, R-R, and ventilation were similar between syncope subjects and control subjects. Syncope subjects experienced an increase in tidal volume and decrease in BP beginning 3 minutes before impending syncope (systolic blood pressure <80 mmHg) necessitated termination of tilt. Approximately 90 seconds before syncope there was a sudden prolongation of R-R interval and increase in amplitude of high and low frequency R-R interval variability, indicating an abrupt enhancement of vagal tone. The increase in respiratory amplitude between 180 and 90 seconds before syncope was not accompanied by changes in R-R interval or R-R variability, suggesting a dissociation between respiration and the respiratory sinus arrhythmia. The coherence analysis showed fewer syncope subjects with coherence between respiratory and R-R interval variabilities and lower transfer magnitudes in syncope subjects compared with control subjects. Nonsyncopal subjects had no change in respiratory, R-R interval, or blood pressure dynamics during matched time periods before the time of syncope. Conclusions-Vasovagal syncope is preceded by a period of hyperpnea and cardiorespiratory decoupling followed by an abrupt increase in cardiovagal tone. Respiratory pumping without inspiratory cardiac slowing may partially counteract preload reduction until sudden bradycardia precipitates syncope.
  • Estimation of subjective workload during motorcycle riding by logistic regression model with indices of heart rate variability, Yasufumi Mizuno, Kiyoko Yokoyama, Seiji Mukai, Junichiro Hayano, Kazuyuki Takata, Japanese Journal of Medical Electronics and Biological Engineering, 36, 1 - 6,   1998年03月01日, To examine if the workload during motorcycle riding is estimated by heart rate variability, we analyzed the multivariate relationships between subjective feeling and indices of R-R interval variability in 14 healthy men during 400-km highway motorcycle driving. Logistic regression analysis revealed that the subjective fatigue assessed by questionnaire was estimated by a two-variate model including mean R-R interval (RRM) and the power of high-frequency component (HFP). By analyzed the pattern of the change in RRM and HFP, the fatigue occurred in the following three conditions: 1) increases in both RRM and HFP, 2) decreased RRM with increased HFP, and 3) decreases in both RRM and HFP, which seemed to correspond to the situations of 1) decreased arousal level, 2) difficulty in the concentration to drive despite high arousal level, and 3) maintaining concentration ability under distress, respectively. These results indicate that the subjective workload during motorcycle riding is estimated from autonomic indices of heart rate variability. The regression model obtained in this study seems useful for the quantitative assessment of the effects of difference in machine and in driving condition on the workload during motorcycle riding.
  • Circadian rhythms of atrioventricular conduction properties in chronic atrial fibrillation with and without heart failure, J Hayano, S Sakata, A Okada, S Mukai, T Fujinami, JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY, 31, (1) 158 - 166,   1998年01月, 査読有り, Objectives. We examined the circadian variations in atrioventricular (AV) conduction properties during atrial fibrillation (AF) by a technique based on the Lorenz plot of successive ventricular response (VR) intervals and analyzed their relations with clinical features. Background. The VR interval in chronic AF shows circadian variation, which is attenuated in patients,vith an increased risk of death, Although the VR interval is determined by the dynamic processes in the AV node randomly stimulated by rapid atrial activity, the circadian variations of the AV conduction properties related to this mechanism are unknown. Methods. In 48 patients with chronic AF, Lorenz plots were generated on overlapping sequential segments of 512 VR intervals in 24-h ambulatory electrocardiograms, For each scatter plot, the 1.0-s intercept of the lower envelope (LE1.0) of the plot and the degree of scatter above the envelope (root mean square difference from the envelope [scattering index]) were measured for estimating AV node refractoriness and concealed AV conduction, respectively. Results. In all patients, a significant circadian rhythm was observed for the average VR interval, LE1.0 and scattering index, with an acrophase occurring at night, The mesor, amplitude and acrophase of LE1.0 and the scattering index closely and independently correlated with the corresponding rhythm variables of the average VR interval (partial r(2) 0.98, 0.86 and 0.68 for LE1.0 and 0.98, 0.92 and 0.92 for scattering index), The amplitudes of these measures were lower in patients with congestive heart failure (CHF) even after adjustment for the effects of age, duration of AF, medications, left atrial diameter and blood pressure (p < 0.01 for all). Conclusions. These results suggest that 1) both AV node refractoriness and the degree of concealed AV conduction during AF may show a circadian rhythm; 2) the circadian rhythms of these properties may independently contribute to the circadian variation of the VR interval; and 3) these circadian rhythms may be attenuated in patients with CHF. (C) 1998 by the American College of Cardiology.
  • Fractional removal rate of fat emulsion (K-2) remains to be low in apoE3/3 phenotype subjects with serum triglyceride level above 180mg/dl, R Ikeuchi, N Sakuma, J Hayano, T Fujinami, LIFE SCIENCES, 62, (7) 665 - 671,   1998年01月, 査読有り, The relation between fractional catabolic rate (IG) Of an intravenously injected fat emulsion, Intralipid(R), and the level of serum triglyceride (TG) was evaluated to cast light on TG-rich lipoprotein metabolism in 182 subjects who were homozygotes for the most common form of apoE3/3. Both normolipidemic individuals and primary hyperlipidemic patients were included. To assess the influence of variation in the apoE phenotype on fat emulsion metabolism, 25 subjects with the apoE 4/3 phenotype and 21 with apoE 3/2 phenotype were also evaluated. In the apoE 3/3 subjects, K2 decreased with increasing TG level up to 180mg/dl, but above 180mg/dl, K2 remained at a constant level. This TG value was therefore concluded to be a cut off beyond which the TG-dependent decrease in K2 disappeared. No aparent correlation between K2 and serum TG was observed in subjects with apoE 4/3 or 3/2 phenotypes. In subjects with TG above 180mg/dl, presumably both accelerated synthesis and limited removal are involved in the development of their hypertriglyceridemia. Since K2 demonstrated little change with increase of TG over 180mg/dl in apoE 3/3 subjects, we concluded that the capacity to catabolize fat emulsion reaches a kinetic saturation. The TG value of 180mg/dl may be a physiological significance. The relation between K2 and TG was specific in apoE 3/3, as it was not observed in subjects having apoE 4/3 or 3/2 phenotypes.
  • Respiratory sinus arrhythmia. A phenomenon improving pulmonary gas exchange and circulatory efficiency, J. Hayano, F. Yasuma, A. Okada, S. Mukai, T. Fujinami, Pneumologie, 51,   1997年12月01日
  • Coronary disease-prone behavior among Japanese men: job-centered lifestyle and social dominance. Type A Behavior Pattern Conference., Hayano J, Kimura K, Hosaka T, Shibata N, Fukunishi I, Yamasaki K, Mono H, Maeda S, American heart journal, 134, (6) 1029 - 1036,   1997年12月, 査読有り
  • Spectral characteristics of ventricular response to atrial fibrillation., Hayano J, Yamasaki F, Sakata S, Okada A, Mukai S, Fujinami T, The American journal of physiology, 273, (6 Pt 2) H2811 - 6,   1997年12月, 査読有り
  • Stability over time of circadian rhythm of variability of heart rate in patients with stable coronary artery disease, J Hayano, W Jiang, R Waugh, C OConnor, D Frid, JA Blumenthal, AMERICAN HEART JOURNAL, 134, (3) 411 - 418,   1997年09月, 査読有り, Reproducibility of circadian rhythm of variability in heart rate was studied in 40 patients with stable coronary artery disease who underwent 48-hour ambulatory electrocardiographic recordings at baseline (time 1) and after 4 months (time 2). The standard deviation of the R-R interval and the low-frequency (0.04 to 0.15 Hz) and high-frequency (0.15 to 0.45 HI) components of variability in heart rate were assessed every 5 minutes. In 35 patients a significant circadian rhythm was observed at both time 1 and time 2 in the standard deviation of the R-R interval, with the acrophase occurring at around 5:00 AM, in the high-frequency amplitude with the acrophase around 3:00 AM, and in the low-frequency/high-frequency ratio with the acrophase around noon. In these patients, parameters of circadian rhythm (mesor, amplitude, and acrophase) showed good within-individual reproducibility with an intraclass correlation coefficient of 0.63 to 0.95 (p < 0.001 for all). In the patients who showed inconsistency about the significance of circadian rhythm between time 1 or time 2, the amplitude of circadian rhythm, even if significant, was found in the lowest five values in the distribution. We conclude that the circadian rhythms of cardiac autonomic activity are stable over time within individual patients with stable coronary artery disease.
  • Simulated analysis of method to calculate HF power in the power spectral density function of heart rate variability, Yasufumi Mizuno, Kiyoko Yokoyama, Seiichirou Sakata, Junichiro Hayano, Kazuyuki Takata, Japanese Journal of Medical Electronics and Biological Engineering, 35, 288 - 296,   1997年01月01日, The power of the high-frequency (HF) region in the power spectral density function of heart rate variability has been recognized as an indicator of parasympathetic nervous system activity and is expected to be applicable as an evaluation parameter not only for the autonomic nervous system but also for mental and physical workload. To quantify HF power in accordance with the power spectral density (PSD) estimated by Fast Fourier Transform (FFT) or autoregressive model, several kinds of different methods have been suggested. These methods, for example, calculation of the PSD area from 0.15 Hz to 0.5 Hz, calculation of the area of the specific band width around the HF component and that utilizing the peak value of the HF component, do not always yield the same result in the tendency of HF power. To evaluate the performance of these methods quantitatively, simulation data were induced and the 'error rate' of each method was calculated and compared. The error rate showed that the method by Which PSD was estimated by FFT and the HF power calculated by the area of specific band width around the HF component was robust against noise and was effective in measuring HF power in the spontaneous breathing condition.
  • Biological Significance of Heart Rate Variability, J. Hayano, A. Okada, F. Yasuma, Japanese Journal of Artificial Organs, 25, 870 - 880,   1996年12月01日
  • Analysis of autonomous nerve response to tilt test by new HRV parameters, Masanori Moyoshi, Kiyoko Yokoyama, Yosaku Watanabe, Kazuyuki Takata, Seiji Mukai, Akiyoshi Okada, Jun Ichiro Hayano, Japanese Journal of Medical Electronics and Biological Engineering, 34, 161 - 170,   1996年08月05日, In this study, the parameters obtained from the impulse response function in the time domain are proposed as new pamameters for evaluation of HRV (heart rate variability). The impulse response function is estimated from the autoregressive model by which the R R interval time series is expressed. HRV during graded head-up tilt was analyzed using the parameters, ARV, TP, heart rate, CV(R-R), and a power spectrum density function. RII, power, time constant, and settling time were obtained from the impulse response function. The RHI is the summation of the impulse response function during the transient decreasing of the function. The power is the average value of the square of the impulse response function of the maximum settling time. The time constant is the time to reach the output value of the system when stimulation is input to 1/c or less. The settling time is the time for the value of the impulse response function to become .0.1 or less. ARV expresses the irregularity of the time series, TP evaluates the adjustment function of the system. The subjects were the healthy males aged 19 to 27 years old. The tilt angle was 0, 20, 30, 45, 60, 90, and 0 degrees, and it was changed, respectively, every four minutes. As a result, RH1, power and TP showed a high correlation between LF/HE, that is, the index of sympathetic nerve activity. ARV exhibited a high correlation between HF, that is, the index of the parasympathetic nerve. It was possible to analyze the autonomous nerve response by TP, ARV, RHI and the power of the impulse response function. With these parameters, the realization of a simple, portable autonomous nerve response analysis device targeting real-time, non-stationary data is expected.
  • Respiratory sinus arrhythmia - Phenomenon improving pulmonary gas exchange and circulatory efficiency, J Hayano, F Yasuma, A Okada, S Mukai, T Fujinami, CIRCULATION, 94, (4) 842 - 847,   1996年08月, 査読有り, Background The primary mechanisms of respiratory sinus arrhythmia (RSA) are understood to be the modulation of cardiac vagal efferent activity by the central respiratory drive and the lung inflation reflex, and the degree of RSA increases with cardiac vagal activity. However, it is unclear whether RSA serves an active physiological role or merely reflects a passive cardiovascular response to respiratory input. We hypothesized that RSA benefits pulmonary gas exchange by matching perfusion to ventilation within each respiratory cycle. Methods and Results In seven anesthetized dogs, a model simulating RSA was made. After elimination of endogenous autonomic activities, respiration-linked heartbeat fluctuations were generated by electrical stimulation of the right cervical vagus during negative pressure ventilation produced by phrenic nerve stimulation (diaphragm pacing). The vagal stimulation was performed in three conditions: phasic stimulation during expiration (artificial RSA) and during inspiration (inverse RSA) and constant stimulation (control) causing the same number of heartbeats per minute as the phasic stimulations. Although tidal volume, cardiac output, and arterial blood pressure were unchanged, artificial RSA decreased the ratio of physiological dead space to tidal volume (VD/VT) and the fraction of intrapulmonary shunt (Q(sp)/Q(t)) by 10% and 51%, respectively, and increased O-2 consumption by 4% compared with control. Conversely, reverse RSA increased VD/VT and Q(sp)/Q(t) by 14% and 64%, respectively, and decreased O-2 consumption by 14%. Conclusions These results support our hypothesis that RSA benefits the pulmonary gas exchange and may improve the energy efficiency of pulmonary circulation by ''saving heartbeats.''
  • Effect of slowed respiration on cardiac parasympathetic response to threat, M Sakakibara, J Hayano, PSYCHOSOMATIC MEDICINE, 58, (1) 32 - 37,   1996年01月, 査読有り, The present study was designed to examine the effect of voluntarily slowed respiration on the cardiac parasympathetic response to a threat: the anticipation of an electric shock. Thirty healthy college students were randomly assigned to the slow, fast, and nonpaced breathing groups (10 subjects each). Subjects in the slow and fast paced breathing groups regulated their breathing rate to 8 and 30 cpm, respectively, and those in the nonpaced breathing group breathed spontaneously. Immediately after the period of paced or nonpaced breathing for 5 minutes, the subjects were exposed for 2 minutes to the anticipation of an electric shock during breathing paced at 15 cpm. The amplitude of the high frequency (HF) component of the heart rate variability, an index of cardiac parasympathetic tone, significantly decreased during the threat in the fast and nonpaced breathing groups, whereas it was unchanged in the slow paced breathing group. No significant difference was observed among the three groups in the amplitude of respiration during the threat. Results suggest that a slowed respiration decreases the cardiac parasympathetic withdrawal response to the threat. This study provides a rationale for the therapeutic uses of the slowed respiration maneuver in attenuating the cardiac autonomic responses in patients with anxiety disorder.
  • Autonomic dysfunction in hemodialysis patients with persistent hypotension., Takahashi H, Matsuo S, Toriyama T, Kawahara H, Hayano J, Nephron, 72, (3) 418 - 423,   1996年, 査読有り
  • Association between Type A behavior pattern and coronary artery spasm in Japanese patients, R Hori, T Suzuki, J Hayano, INTERNATIONAL JOURNAL OF BEHAVIORAL MEDICINE, 3, (3) 221 - 232,   1996年, 査読有り, The relations between the Jenkins Activity Survey (JAS) Type A score and coronary atherosclerosis and spasm were examined in 192 patients (115 men and 77 women) undergoing coronary angiography. Thirty-nine men (34%) and 12 women (16%) had significant (greater than or equal to 75%) coronary stenosis. In 97 patients (54 men and 43 women) with no significant coronary stenosis, a coronary spasm provocation test by 0.2 to 0.4 mg of ergometrine was performed, by which a significant focal spasm (greater than or equal to 75% reduction of luminal diameter) was induced in 22 men (40%) and 5 women (12%). Men who showed a significant focal spasm had a higher Type A score than men who showed no such spasm (1.9 +/- 8.4 vs. -2.4 +/- 8.3, p < 0.05). Discriminant analysis in male patients revealed that the induction of coronary spasm can be predicted by the JAS Type A score and smoking habit (p = 0.04). No such association was found for female patients. These results suggest that the Type A behavior pattern as assessed by the JAS may be associated with coronary spasm in Japanese men without significant coronary stenosis.
  • ASSESSMENT OF AUTONOMIC FUNCTION IN MYOTONIC-DYSTROPHY BY SPECTRAL-ANALYSIS OF HEART-RATE-VARIABILITY, K INOUE, H OGATA, M MATSUI, J HAYANO, S MIYAKE, M KUMASHIRO, M KUNO, F TOKONAMI, H AII, J AKATSU, K FURUSAWA, T OKAZAKI, JOURNAL OF THE AUTONOMIC NERVOUS SYSTEM, 55, (1-2) 131 - 134,   1995年10月, 査読有り, We analyzed by means of autoregressive spectral analysis the spontaneous beat-to-beat heart-rate variability (HRV) of 10 myotonic dystrophy (MD) patients (4 men and 6 women, aged 37-53 years) and 10 age- and sex-matched healthy, sedentary humans (central) at rest in the supine position. All MD patients had no cardiac conduction disturbances (i.e., atrioventricular or intraventricular conduction defects) on 12-lead electrocardiogram and were able to walk and perform daily activities. In the MD group, the total power, the power of the low-frequency component (a marker of sympathetic and vagal modulation of heart rate) and that of the high-frequency component (a marker of vagal modulation of heart rate) were smaller than those in the control group (P < 0.01, P < 0.05 and P < 0.05, respectively). The results of this study suggest that the cardiovascular autonomic nervous system contributing to the HRV may be disturbed even in the MD patients who can walk and perform daily activities. Therefore, one must give careful consideration to the cardiovascular autonomic dysfunction, as well as the cardiac conduction disturbance in the MD patients.
  • Lesser vagal withdrawal during isometric exercise with age., Taylor JA, Hayano J, Seals DR, Journal of applied physiology (Bethesda, Md. : 1985), 79, (3) 805 - 811,   1995年09月, 査読有り
  • ASSESSMENT OF AUTONOMIC FUNCTION IN TRAUMATIC QUADRIPLEGIC AND PARAPLEGIC PATIENTS BY SPECTRAL-ANALYSIS OF HEART-RATE-VARIABILITY, K INOUE, H OGATA, J HAYANO, S MIYAKE, T KAMADA, M KUNO, M KUMASHIRO, JOURNAL OF THE AUTONOMIC NERVOUS SYSTEM, 54, (3) 225 - 234,   1995年09月, 査読有り, We analyzed by means of autoregressive spectral analysis the spontaneous beat-to-beat heart rate variability (HRV) of quadriplegic and paraplegic male subjects at rest in the supine position. In agreement with our previous study, in nine of 15 quadriplegic patients only the high-frequency (HF: center frequency = respiratory frequency) component (a marker of vagal modulation of heart rate) was observed. In contrast, in six of the quadriplegic patients both the KF component and the low-frequency (LF: center frequency at approx. 0.1 Hz, 0.03-0.15 Hz in this study) component (a marker of sympathetic and vagal modulation of heart rate) were observed. However, in six quadriplegic patients who presented the LF component, (i) the center frequency of the LF component was lower than that in 10 healthy, sedentary, age-matched males (control I) (P < 0.01), (ii) the power of the HF component was smaller than that in the control-I group (P < 0.01) and (iii) the LF/HF power ratio (an index of sympathovagal balance) was larger than that in the control-I group (P < 0.05). On the other hand, in nine paraplegic patients with an intact 1st-4th thoracic spinal cord, from which the cardiac sympathetic nerves originate, the total power, the power of the LF component and that of the HF component were smaller than those in nine healthy, sedentary, age-matched males (control II) (P < 0.05, P < 0.01 and P < 0.01, respectively). These results suggest that (i) in quadriplegic patients who presented the LF component, the physiological mechanism of the LF component may be different from that in the control-I subjects (e.g., contribution of spinal sympathetic nervous system), (ii) in paraplegic patients having both the intact cardiac sympathetic nerves and the intact vagal cardiac nerves, the dysfunction of the sympathetic nerves to the vessels below the level of the lesion and/or the compensatory vagal suppression may contribute in part to the low HRV and (iii) it is possible that in some clinical pathophysiological conditions the dysfunction of the sympathetic nerves to the vessels and/or the compensatory vagal suppression may affect the HRV. Therefore, one must give careful consideration to the definition (e.g., center frequency) and interpretation of the LF component and to the interpretation of results when analyzing the HRV in humans by means of power spectral analysis.
  • 'Non-hypotensive' hypovolaemia reduces ascending aortic dimensions in humans., Taylor JA, Halliwill JR, Brown TE, Hayano J, Eckberg DL, The Journal of physiology, 483 ( Pt 1), 289 - 298,   1995年02月, 査読有り
  • A study of the clinical effect and its mechanism of the diazepam infusion sleeping therapy, T. Yamamoto, T. Takeuchi, K. Fukushima, M. Ando, J. Hayano, T. Kuboki, H. Suematsu, Japanese Journal of Psychosomatic Medicine, 35, 273 - 279,   1995年01月01日, We developed diazepam infusion sleeping therapy (DIST) that was completed by reforming diazepam sedation threshold test which had been developed to estimate the anxiety of patients objectively and quantitatively. We have applied this therapeutic method to clinical use. As the result, we have obtained some knowledge. The results obtained were as follows: (1) The diseases that DIST was very effective for were vegitative dystonia, generalized anxiety disorder, panic disorder etc. (n = 30). The diseases that DIST was effective for were generalized anxiety disorder, panic disorder, depression, vegitative dystonia etc. (n = 50). The diseases that was ineffective for were generalized anxiety disorder, depression, anorexia nervosa, mesencephalosis etc. (n = 42). (2) On the clinical effect, more diazepam was required in the effective group and the very effective group compared with the ineffective group significantly (p < 0.05, n = 92). (3) The diazepam dosage of DIST was significantly higher in the IV area of CMI (Cornell Medical Index) compared with the I or II or III area of CMI (p < 0.05, n = 78). (4) Concerning the vital sign, the blood pressure decreased significantly at the sleeping point and after 30 minutes of DIST. The pulse and the respiratory rate increased significantly at the sleeping point of DIST (p < 0.05, n = 44). (5) Concerning the autonomic nerve function, there was no significant difference in the value of coefficient of component variance (CCV) before and after DIST. But, the LF (low frequent)/HF (high frequent) component, which can be an index of the domination of the sympathetic nerve activity to the parasympathetic nerve activity, was decreased on the next day after DIST and six days after DIST compared with the LF/HF component before DIST significantly (p < 0.05, n = 14). (6) MAS (Manifest Anxiety Scale) score was decreased significantly in six days after DIST compared with the score before DIST (p < 0.05, n = 14). As mentioned above, DIST seemed to be a very effective therapy to diminish the clinical signs and symptoms (especially anxiety state) of psychosomatic diseases.
  • Heart rate and blood pressure variabilities during graded head-up tilt., Mukai S, Hayano J, Journal of applied physiology (Bethesda, Md. : 1985), 78, (1) 212 - 216,   1995年01月, 査読有り
  • Assessment of frequency shifts in R-R interval variability and respiration with complex demodulation., Hayano J, Taylor JA, Mukai S, Okada A, Watanabe Y, Takata K, Fujinami T, Journal of applied physiology (Bethesda, Md. : 1985), 77, (6) 2879 - 2888,   1994年12月, 査読有り
  • [Periodical blood pressure variation during cardiopulmonary bypass--effects of cervicothoracic epidural anesthesia and phentolamine]., Sasano H, Sasano N, Ishida S, Oda N, Miura M, Baba E, Yamada M, Moriya T, Takamiya T, Hayano J, Masui. The Japanese journal of anesthesiology, 43, (10) 1454 - 1460,   1994年10月, 査読有り
  • Effects of respiratory interval on vagal modulation of heart rate., Hayano J, Mukai S, Sakakibara M, Okada A, Takata K, Fujinami T, The American journal of physiology, 267, (1 Pt 2) H33 - 40,   1994年07月, 査読有り
  • EFFECT OF RELAXATION TRAINING ON CARDIAC PARASYMPATHETIC TONE, M SAKAKIBARA, S TAKEUCHI, J HAYANO, PSYCHOPHYSIOLOGY, 31, (3) 223 - 228,   1994年05月, 査読有り, To examine the hypothesis that the relaxation response is associated with an increase in cardiac parasympathetic tone, the frequency components of heart rate variability during relaxation training were investigated in 16 college students. Electrocardiograms and pneumograms were recorded during a 5-min baseline period followed by three successive 5-min sessions of the autogenic training (relaxation) or by the same periods of quiet rest (control), while subjects breathed synchronously with a visual pacemaker (0.25 Hz). Although neither the magnitude nor the frequency of respiration showed a significant difference between relaxation and control, the amplitude of the high-frequency component of heart rate variability increased only during relaxation (p =.008). There was no significant difference in the ratio of the low-frequency (0.04-0.15 Hz) to the high-frequency amplitudes. The increased high-frequency amplitude without changes in the respiratory parameters indicates enhanced cardiac parasympathetic tone. Thus, our results support the initial hypothesis of this study. Enhanced cardiac parasympathetic tone may explain an important mechanism underlying the beneficial effect of the relaxation response.
  • Body image in Japanese junior-high-school students - Impact of slender images mediated by mass communication, S. Takeuchi, J. Hayano, R. Hori, S. Mukai, T. Fujinami, Japanese Journal of Psychosomatic Medicine, 33, 691 - 695,   1993年12月01日
  • Body image and self image (2nd report) - Low self-esteem and over-estimation of body weight, S. Takeuchi, J. Hayano, R. Hori, S. Mukai, Japanese Journal of Psychosomatic Medicine, 33, 697 - 703,   1993年12月01日
  • RELATION OF CARDIOVASCULAR-RESPONSES TO MENTAL STRESS AND CARDIAC VAGAL ACTIVITY IN CORONARY-ARTERY DISEASE, W JIANG, J HAYANO, ER COLEMAN, MW HANSON, DJ FRID, C OCONNOR, D THURBER, RA WAUGH, JA BLUMENTHAL, AMERICAN JOURNAL OF CARDIOLOGY, 72, (7) 551 - 554,   1993年09月, 査読有り, Forty-six patients with documented coronary artery disease were studied to examine the relation of cardiovascular reactivity to mental stress and cardiac vagal activity. Cardiac vagal activity was measured by means of frequency-domain analysis of heart rate variability with 48-hour out-of-hospital Holter monitoring. The amplitude of the high-frequency component (0.16 to 0.40 Hz) of heart rate variability is considered to be an index of cardiac vagal activity. Cardiovascular reactivity was measured in the laboratory during a 3-minute public speaking task. Results revealed that (1) the amplitude of the high-frequency component was significantly higher during sleep (24.6 +/- 11.3 ms) than during waking (18.2 +/- 8.0 ms) (p = 0.002); (2) compared to subjects with low diastolic pressure reactivity, those who displayed high diastolic blood pressure reactivity exhibited a significantly lower amplitude of the high-frequency component (19.2 +/- 6.9 vs 23.4 +/- 9.6 ms, p = 0.03). These results indicate that decreased cardiac vagal activity may contribute to the exaggerated diastolic blood pressure reactivity to mental stress in patients with coronary artery disease.
  • Continuous assessment of hemodynamic control by complex demodulation of cardiovascular variability., Hayano J, Taylor JA, Yamada A, Mukai S, Hori R, Asakawa T, Yokoyama K, Watanabe Y, Takata K, Fujinami T, The American journal of physiology, 264, (4 Pt 2) H1229 - 38,   1993年04月, 査読有り
  • REGULATION OF QT INTERVAL DURING POSTURAL TRANSITORY CHANGES IN HEART-RATE IN NORMAL SUBJECTS, A YAMADA, J HAYANO, K HORIE, K IEDA, S MUKAI, M YAMADA, T FUJINAMI, AMERICAN JOURNAL OF CARDIOLOGY, 71, (11) 996 - 998,   1993年04月, 査読有り
  • SINGLE ADMINISTRATION OF CAPTOPRIL AND COMBINED USE WITH BETA-BLOCKER AND OR THIAZIDE DIURETIC IN THE TREATMENT OF ESSENTIAL-HYPERTENSION, S YONEDA, T KAKO, M KOKETSU, J HAYANO, T ASAKAWA, T FUJINAMI, T KATO, ANGIOLOGY, 42, (11) 914 - 923,   1991年11月, 査読有り, Thirty-four patients with essential hypertension at WHO stage I or II were divided into three groups. Group I consisted of 22 cases who displayed normal renin activity (NR) or low renin activity (LR) and who received a single administration of captopril. Group II consisted of 6 cases given beta-blockers after administration of captopril. Group III consisted of 6 cases in whom beta-blocker was replaced with thiazide diuretics after administration of captopril alone. Blood pressure decreased significantly by captopril treatment alone in group I of the NR and LR subgroups (except for the diastolic blood pressure [DBP] of the NR subgroup) and fell below the target blood pressure (SBP of 165 mmHg and DBP of 95 mmHg) in 86% of the NR subgroup and 73% of the LR subgroup. Combined treatment with captopril and beta-blocker in Group II did not decrease blood pressure any lower than with captopril alone treatment and achieved the target blood pressure in only 50% of the patients. In group III, combined treatment with catopril and thiazide achieved the target blood pressure in 100% of the patients. Plasma renin activity (PRA) was increased by captopril but reduced by captopril in combination with beta-blocker. However, when beta-blocker was replaced with thiazide, PRA increased. The serum sodium concentration was significantly reduced in the LR subgroup after a single administration of captopril, but there was no other variation.
  • Continuous-wave Doppler echocardiography for evaluating left ventricular performance--clinical significance of a new systolic time interval., Ohte N, Nakano S, Hashimoto T, Narita H, Hayano J, Fujinami T, Japanese circulation journal, 55, (5) 459 - 464,   1991年05月, 査読有り
  • SEVERITY OF CORONARY ATHEROSCLEROSIS CORRELATES WITH THE RESPIRATORY COMPONENT OF HEART-RATE-VARIABILITY, J HAYANO, A YAMADA, S MUKAI, Y SAKAKIBARA, M YAMADA, N OHTE, T HASHIMOTO, T FUJINAMI, K TAKATA, AMERICAN HEART JOURNAL, 121, (4) 1070 - 1079,   1991年04月, 査読有り, Decreased vagal activity is frequently observed in coronary artery disease, but the mechanism of this association is unknown. We investigated cardiac autonomic function by relating heart rate spectral components to clinical and angiographic findings in 80 patients who were undergoing coronary angiography. The age- and sex-adjusted magnitude of the respiratory spectral component, which is an index of cardiac vagal tone, showed a significant negative correlation with the extent of coronary atheromatosis (r = -0.43, p < 0.0001) and a less significant negative correlation with the severity of coronary stenosis (r = -0.30, p = 0.0070). These relationships were independent of previous myocardial infarction and of left ventricular function. Stepwise regression analysis showed that the respiratory spectral component contributed to atheromatosis independently of established coronary risk factors (partial R2 = 9.4%, p = 0.002), but not to stenosis. Our results support the hypothesis that decreased cardiac vagal activity is associated with an increased risk of coronary atherosclerosis.
  • Body image and self image in 712 junior-high school students, S. Takeuchi, J. Hayano, T. Kamiya, R. Hori, S. Mukai, T. Fujinami, Japanese Journal of Psychosomatic Medicine, 31, 367 - 373,   1991年01月01日
  • ACCURACY OF ASSESSMENT OF CARDIAC VAGAL TONE BY HEART-RATE-VARIABILITY IN NORMAL SUBJECTS, J HAYANO, Y SAKAKIBARA, A YAMADA, M YAMADA, S MUKAI, T FUJINAMI, K YOKOYAMA, Y WATANABE, K TAKATA, AMERICAN JOURNAL OF CARDIOLOGY, 67, (2) 199 - 204,   1991年01月, 査読有り, The correlations of 11 indexes of heart rate variability were examined with pharmacologically determined cardiac vagal tone in 15 normal subjects at supine rest. After sympothetic influences by intravenous propranolol were eliminated, RR interval variability was measured for 10 minutes under controlled respiration (0.25 Hz), and cardiac vagal tone was determined as the decrease in mean RR interval following complete vagal blockade with atropine. Time domain indexes (standard deviation, coefficient of variance and mean successive difference) correlated strongly with vagal tone (r = 0.87, 0.81 and 0.92, respectively; p < 0.001 for all). The same was true for frequency domain indexes for the high-frequency (0.25 Hz) component calculated both by autoregressive spectrum analysis (square root of power and coefficient of component variance) and by fast Fourier transform (mean amplitude) (r = 0.91, 0.85 and 0.86, respectively; p < 0.0001 for all). However, frequency domain indexes for the low-frequency spectral component (0.03 to 0.15 Hz) correlated less strongly (r = 0.69, 0.55 and 0.70, respectively), and the fraction of power [power/(total power > 0.03 Hz)] of both components showed no correlation. Principal component analysis showed that the first 6 indexes with strong correlations contained solely the first principal component closely related to vagal tone, whereas the remaining 5 indexes also contained the second component unrelated to vagal tone. These results indicate that most of the time and frequency domain analyses in use provides an accurate and common measure of cardiac vagal tone at rest.
  • NONINVASIVE EVALUATION OF LEFT-VENTRICULAR PERFORMANCE WITH A NEW SYSTOLIC-TIME INTERVAL, THE Q-V PEAK, AND COMPARISON WITH ESTABLISHED SYSTOLIC-TIME INTERVALS, N OHTE, T HASHIMOTO, H NARITA, R TAKASE, K KOBAYASHI, J HAYANO, T FUJINAMI, AMERICAN JOURNAL OF CARDIOLOGY, 66, (12) 1018 - 1020,   1990年10月, 査読有り
  • CORONARY RISK-FACTORS IN ANGIOGRAPHICALLY DEFINED PATIENTS WITH CHEST PAIN, T FUJINAMI, H HIRATA, J HAYANO, N OHTE, M KOHKETSU, T HASHIMOTO, JAPANESE JOURNAL OF MEDICINE, 29, (5) 462 - 468,   1990年09月, 査読有り, Coronary risk factors were assessed in 186 consecutive patients who received coronary angiography. The severity of coronary luminal narrowing was scored as the coronary sclerosis index (CSI). Patients were divided into normal coronary arteries (N, n = 72), coronary sclerosis without infraction (C, n = 73) and previous myocardial infarction (MI, n = 41). The CSI increased with age. A significant difference in serum triglycerides, HDL cholesterol and atherogenic index was observed between Groups C or MI and N. Multivariate analysis revealed that CSI had correlated with total- and HDL-cholesterol, uric acid and age in subjects under 55 years; and with age, blood sugar, factor H and HDL cholesterol in those of 55 years or over. When patients were classified by their total and LDL cholesterol level, a significantly different CSI was found between the desirable and high cholesterol levels in subjects under the age of 55, but it was not significant in those over 55. Therefore, disorders in lipid metabolism should be corrected in early middle age.
  • DECREASED MAGNITUDE OF HEART-RATE SPECTRAL COMPONENTS IN CORONARY-ARTERY DISEASE - ITS RELATION TO ANGIOGRAPHIC SEVERITY, J HAYANO, Y SAKAKIBARA, M YAMADA, N OHTE, T FUJINAMI, K YOKOYAMA, Y WATANABE, K TAKATA, CIRCULATION, 81, (4) 1217 - 1224,   1990年04月, 査読有り
  • Diurnal variations in vagal and sympathetic cardiac control., Hayano J, Sakakibara Y, Yamada M, Kamiya T, Fujinami T, Yokoyama K, Watanabe Y, Takata K, The American journal of physiology, 258, (3 Pt 2) H642 - 6,   1990年03月, 査読有り
  • Hemorheological effects of coenzyme Q10in patients with ischemic heart disease, Tadashi Kato, Shunki Yoneda, Toshio Kako, Masaaki Koketsu, Junichiro Hayano, Takao Fujinami, Rinsho yakuri/Japanese Journal of Clinical Pharmacology and Therapeutics, 21, 433 - 437,   1990年01月01日, The effects of coenzyme Q10 (CoQ10) on blood rheology were studied in patients with ischemic heart disease. Twenty milligrams of C0Q10 was administrated per os three times daily (total dose 60 mg per day) for two months. Whole blood viscosity was measured at the shear rates of 37. 5, 75, 150 and 375 sec-1with a conplate type viscometer. Whole blood viscosity at each shear rate was decreased after administration of CoQio. Casson viscosity and yield shear stress were calculated using the Casson plot method from the ‘ blood viscosity at each shear rate. Yield shear stress was significantly lowered after admin-istration of CoQio, while Casson viscosity was not significantly changed. Both the hemo- starting- point and hemolysis end point represented by mOsm were determined by means of the coil plant centrifuge method. These parameters, which reflect osmotic fragility of erythrocytes, showed significant decreases after administration of CoQio. After the blood was diluted with a phosphate buffer solution, passage time through the Nuclepore membrane with a pore size of 5 ^m was measured 10 min after the in vitro administration of CoQ10 of 5 pg. This passage time was significantly shortened after administration of CoQio. There were no significant changes in hematocrit and fibrinogen after administration of CoQ10. These results show that administration of CoQio improves hemorheology in ischemic heart disease, and thus suggests that oxygen transport to heart muscle is increased by treatment of CoQ10. © 1990, The Japanese Society of Clinical Pharmacology and Therapeutics. All rights reserved.
  • SHORT-TERM AND LONG-TERM EFFECTS OF CIGARETTE-SMOKING ON HEART-RATE-VARIABILITY, J HAYANO, M YAMADA, Y SAKAKIBARA, T FUJINAMI, K YOKOYAMA, Y WATANABE, K TAKATA, AMERICAN JOURNAL OF CARDIOLOGY, 65, (1) 84 - 88,   1990年01月, 査読有り
  • TYPE-A BEHAVIOR PATTERN IN JAPANESE EMPLOYEES - CROSS-CULTURAL-COMPARISON OF MAJOR FACTORS IN JENKINS-ACTIVITY-SURVEY (JAS) RESPONSES, J HAYANO, S TAKEUCHI, S YOSHIDA, H JOZUKA, N MISHIMA, T FUJINAMI, JOURNAL OF BEHAVIORAL MEDICINE, 12, (3) 219 - 231,   1989年06月, 査読有り
  • Type A behaviors pattern in panic disorders, H. Jozuka, J. Hayano, S. Yoshida, Japanese Journal of Psychosomatic Medicine, 28, 345 - 349,   1988年01月01日
  • [A multivariate autoregressive model of R-R intervals and blood pressure time series]., Watanabe Y, Yokoyama K, Takata K, Hayano J, Fujinami T, Iyo denshi to seitai kogaku. Japanese journal of medical electronics and biological engineering, 24, (7) 511 - 516,   1986年12月, 査読有り
  • [A study on experimental pancreatitis]., HAYANO J, [Hokkaido igaku zasshi] The Hokkaido journal of medical science, 36, 89 - 100,   1961年02月, 査読有り

MISC

  • Relationship between Subjective Assessment of Sleep Quality and Heart Rate Variability during Sleep, E. Yuda, Y. Yoshida, J. Hayano, 2018 IEEE International Conference on Consumer Electronics-Taiwan, ICCE-TW 2018,   2018年08月27日, © 2018 IEEE. Assessment of autonomic function during sleep is gathering attention as an indicator of sleep quality that is closer to subjective assessment than that from polysomnography or actigraphy. This study examined the relationships between subjective sleep quality assessment and heart rate variability (HRV) indices, particularly those derived from a new sleep index (Hsi) that we have recently developed to detect non-REM sleep. We studied 18 sets of nighttime ECGs and the responses to sleep inventory questionnaires obtained from 5 male workers. We observed that subjective quality was associated with sleep latency estimated by Hsi and with the length of time in bed excluding the period of non-REM sleep in these subjects.
  • ALLSTAR心拍変動ビッグデータ解析からみた日本人の老衰死率の地域差と健康指標の関連, 湯田恵美, 吉田豊, 木曽原昌也, 早野順一郎, 電子情報通信学会技術研究報告, 118,   2018年05月24日
  • 眠気に伴う生理学的変化 心拍および脳波による検討, 湯田恵美, 吉田豊, 川嶋宏行, 山本浩彰, 田中春仁, 早野順一郎, 自動車技術会大会学術講演会講演予稿集(CD-ROM), 2018,   2018年05月21日
  • Introduction to heart rate variability, Junichiro Hayano, Clinical Assessment of the Autonomic Nervous System,   2016年01月01日, © Springer Japan 2017. Beat-to-beat intervals of cardiac sinus rhythm are not constant but show complex and continuous fluctuations called heart rate variability (HRV). Because HRV disappears with cardiac denervation by complete autonomic blockades or cardiac transplantation, HRV is thought to originate from the brain and to transfer to the heart through the autonomic nervous system. HRV includes a plenty of information not only about autonomic neural cardiac regulations but also about health state and hazard that are captured by the brain. To extract information that meets with particular purposes, various methods have been developed for the analysis of HRV. This chapter explains the basic mechanisms generating HRV and introduces the purposes and corresponding methods for HRV analyses.
  • Heart rate variability (hrv) and sympathetic nerve activity, Ken Kiyono, Junichiro Hayano, Eiichi Watanabe, Yoshiharu Yamamoto, Clinical Assessment of the Autonomic Nervous System,   2016年01月01日, © Springer Japan 2017. The available epidemiological and clinical data implicate increased sympathetic nervous system activity in increased cardiovascular morbidity and mortality and show that it has strong predictive power for mortality and cardiovascular events. Analysis of heart rate variability (HRV) has been widely used as a noninvasive assessment tool for autonomic nervous system function, and results show that reduced and/or abnormal HRV is associated with an increased risk of mortality in cardiac patients such as patients after acute myocardial infarction and patients with congestive heart failure. However, most indices derived from HRV primarily reflect vagal function. In contrast, few indices have been suggested as markers of sympathetic nervous system activity. This chapter reviews characteristics of HRV that have been proposed as potential markers of cardiac sympathetic activity, such as (in the frequency domain) low-frequency (LF) power, short-term scaling exponent, and non-Gaussianity index. While there is no widely accepted and well-tested HRV-based index of cardiac sympathetic activity, we discuss the key issues for the assessment of cardiac sympathetic activity based on HRV analysis.
  • Respiratory sinus arrhythmia and entraining heartbeats with cheyne-stokes respiration: Cardiopulmonary works to be minimal by synchronizing heartbeats with breathing, Fumihiko Yasuma, Junichiro Hayano, Clinical Assessment of the Autonomic Nervous System,   2016年01月01日, © Springer Japan 2017. There are two types of interaction between heartbeats and respiration with different time scales. One is the well-known respiratory sinus arrhythmia (RSA) and another is entraining heartbeats with Cheyne-Stokes respiration (CSR). The latter is the cyclical fluctuation with the clustering heartbeats during the hyperventilation phase of CSR and their scattering during the apnea/hypopnea phase, which we call the Entrainment with CSR. The wisdom of the body for maintaining the homeostasis efficiently could be achieved by synchronizing heartbeats with breathing and consequently by saving the cardiopulmonary works. Analogous to that the RSA benefits the pulmonary gas exchange, we have hypothesized that the Entrainmentwith CSR might function to supply “effective” heartbeats during the hyperventilation phase and save “ineffective” heartbeats during the apneic/hypopneic phase to benefit the pulmonary gas exchange according to our previous investigations on the pulmonary gas exchange and RSA, the control of RSA and respiratory muscles during hypercapnia and hypoxia, the role of vagal nerve on RSA and respiratory muscles, and our clinical experiences in heart failure and atrial fibrillation. The concept that the RSA and Entrainment with CSR would serve for the cardiopulmonary works to be minimal by synchronizing heartbeats with breathing would be tested in the future.
  • Heart rate variability and cardiac diseases, Eiichi Watanabe, Ken Kiyono, Yoshiharu Yamamoto, Junichiro Hayano, Clinical Assessment of the Autonomic Nervous System,   2016年01月01日, © Springer Japan 2017. Heart rate variability (HRV) is a noninvasive methodology for evaluating the autonomic nervous system modulation of the sinoatrial node and to identify patients at risk of cardiac disorders. The contemporary therapeutic use for the HRV analysis is for risk stratification in patients with post-myocardial infarction or heart failure who are prone to have arrhythmic death and who would benefit from implantable cardioverter-defibrillators (ICDs). Although multiple HRV measurements have been developed to achieve a better risk stratification, the HRV measurements have been rarely tested to see whether they harbor a significant power to serve as a practical risk predictor. To date, the only reliable metric to predict the benefit from an ICD is a severely reduced ejection fraction; however, the predictive value of the ejection fraction is relatively low. Because of the high negative predictive value of the HRV, a combination with the ejection fraction may be helpful to identify candidates who are unlikely to benefit from ICD therapy. A more sophisticated risk approach that combines the HRV and other known clinical measures should be developed to provide accurate estimates of the risk to allow patients to make informed treatment decisions. Another requirement is to explore the novel HRV measurements for atrial fibrillation. The prevalence of atrial fibrillation rapidly increases among the aging population and is independently associated with a higher risk of ischemic strokes and excess mortality. The HRV measurements specific for atrial fibrillation may facilitate the risk stratification in such a high-risk population.
  • 心拍変動バイオフィードバック法が睡眠中の心肺系休息機能に及ぼす影響, 榊原雅人, 早野順一郎, 心身医学, 55,   2015年09月01日
  • 外国人教員との英語医療面接の試み, 村上里奈, 金井美晴, 飯塚成志, 三浦裕, 金澤智, 辻田麻紀, 早野順一郎, 医学教育, 46,   2015年07月10日
  • 医療系学部連携による被災地での支援活動, 飯塚成志, 村上里奈, 川出義浩, 鈴木匡, 早野順一郎, 医学教育, 46,   2015年07月10日
  • 心拍変動解析による鍼刺激に対する自律神経反応の評価―腹部鍼刺激の経穴特異性の検討―, 皆川宗徳, 黒野保三, 山田篤, 山田篤, 各務壽紀, 早野順一郎, 自律神経, 52, (2) 145 - 151,   2015年06月15日
  • CKDにおけるAsilsartan治療急性期/慢性期の血圧日内リズムの検討, 佐々木優加子, 福田道雄, 美浦利幸, 不破大祐, 佐藤諒, 荻山義明, 白澤祐一, 吉田篤博, 清野健, 山本義春, 早野順一郎, 大手信之, 日本腎臓学会誌, 57,   2015年04月30日
  • 心拍変動解析deceleration capacityが交感神経系の影響を受ける可能性の検証, 福田道雄, 美浦利幸, 荻山義明, 不破大祐, 佐藤諒, 佐々木優加子, 白澤祐一, 吉田篤博, 清野健, 山本義春, 早野順一郎, 大手信之, 日本腎臓学会誌, 57,   2015年04月30日
  • CKDにおける昼夜別心拍変動と血圧日内リズムの関係, 美浦利幸, 福田道雄, 荻山義明, 不破大祐, 佐藤諒, 佐々木優加子, 白澤祐一, 吉田篤博, 清野健, 山本義春, 早野順一郎, 大手信之, 日本腎臓学会誌, 57,   2015年04月30日
  • 就寝前の心拍変動バイオフィードバック訓練が睡眠中の心肺系休息機能に及ぼす影響, 榊原雅人, 早野順一郎, バイオフィードバック研究, 42, (1) 47 - 56,   2015年04月25日
  • ALLSTAR研究から見えてきたもの, 早野順一郎, 心電図, 35,   2015年03月30日
  • 慢性腎臓病(CKD)診療に心拍変動を活かす, 福田道雄, 美浦利幸, 荻山義明, 磯部優加子, 佐藤諒, 不破大祐, 清野健, 山本義春, 早野順一郎, 大手信之, 日本内科学会雑誌, 104,   2015年02月20日

書籍等出版物

  • Big data technologies and applications, 共著, ALLSTAR Project Investigators. Association between regional difference in heart rate variability and inter-prefecture ranking of healthy life expectancy: ALLSTAR big data project in Japan, Springer Nature,   2017年
  • Clinical assessment of the autonomic nervous system, 早野 順一郎, 共編者(共編著者), Introduction to heart rate variability, Springer Nature,   2016年
  • 9. 循環器疾患と自律神経機能, 早野 順一郎, 共著, 心拍変動による自律神経解析, 医学書院,   2001年

講演・口頭発表等

  • Sleep stage classification by combination of actigraphic and heart rate signals, Junichiro Hayano, Emi Yuda, Yutaka Yoshida, 2017 IEEE International Conference on Consumer Electronics - Taiwan, ICCE-TW 2017,   2017年07月25日, © 2017 IEEE. This paper presents the performance of sleep stage classification by combination of actigraphic and heart rate signals. We studied 40,643 epochs (length 3 min) of polysomnographic data in 289 subjects. Body movement indices derived from actigraphic data and autonomic functional indices from heart rate variability were useful for discriminating between non-REM sleep and waking/REM sleep at 76.9% sensitivity and 74.5% specificity and between REM sleep and waking at 77.2% sensitivity and 72.3% specificity.
  • Fast algorithm of long-range cross-correlation analysis using Savitzky-Golay detrending filter and its application to biosignal analysis, Yutaka Tsujimoto, Yuki Miki, Eiichi Watanabe, Junichiro Hayano, Yoshiharu Yamamoto, Taishin Nomura, Ken Kiyono, 2017 International Conference on Noise and Fluctuations, ICNF 2017,   2017年07月19日, © 2017 IEEE. To evaluate long-range cross-correlated behavior observed in bivariate time series, detrended cross-correlation analysis (DCCA) was proposed. In the DCCA, trends embedded in each time series are eliminated via piecewise least-squares polynomial fitting in the same way as the detrended fluctuation analysis (DFA). In this paper, as an improved variant of DCCA, we propose a DCCA method using the Savitzky-Golay detrending filters and its fast implementation algorithm. In addition, as an application of our method, we analyze the cardiorespiratory interaction.
  • Characteristics of basal heart rate during daily life: Relationships with age, sex, and mean heart rate, Junichiro Hayano, Yutaka Yoshida, Emi Yuda, ACM International Conference Proceeding Series,   2017年05月23日, Vast heart rate (HR) data during daily activities are being accumulated with widespread use of wearable sensors. To interpret the meaning of these HR data, the reference point of HR in individual subject is required. Although resting HR has been used for this purpose, the definition of resting HR has not been established and particularly, the effects of time of the day (circadian rhythm) on resting HR have not been considered. One of the other candidates for the reference point may be basal HR, i.e., the lowest HR in the day. In the present study, we therefore investigated the characteristics of basal HR by examining the effects of age and sex on basal HR and the occurrence time of basal HR during 24 h in 113,341 males and 140,332 females extracted from a 24-h Holter ECG database of the Allostatic State Mapping by Ambulatory ECG Repository (ALLSTAR). Although basal HR decreases with age until 20 yr old in both sexes, it increases slightly with advancing age thereafter. Although the clock time to reach basal HR appears between 02 and 05 h on average, it shows progress or delay depending on the time of life. The difference between 24-h mean and basal HR decrease linearly with age, suggesting that age-dependent decline in the increases in HR with daily activities can be detected by using basal HR as the reference point.
  • Criticality and universality in healthy heart rate dynamics, Zbigniew R. Struzik, Ken Kiyono, Junichiro Hayano, Seiichiro Sakata, Shin Kwak, Yoshiharu Yamamoto, AIP Conference Proceedings,   2005年08月25日, Methodologies originally developed in the field of statistical physics of complex phenomena have been proven to provide new insights into the modeling, description and understanding of the human heart rate regulatory system. Recent studies have shown the heart rate control system to maintain universality properties characteristic of physical systems exhibiting far-from-equilibrium, critical state-like dynamics. Simultaneously, heart rate regulation has been shown to display correlation properties of antagonist dynamics involving antagonist actors, pertinent to some far-from-equilibrium systems. We discuss the range of validity and breakdown scenarios of the universal properties in heart rate regulation leading to the diagnostic capability and also to new challenges for both analysis methods and up-to-date simulation models. © 2005 American Institute of Physics.
  • Probing temporal correlation in ventricular interbeat intervals during atrial fibrillation with local continuous DFA, Stefan Heinrichs, Zbigniew, R. Struzik, Zbigniew, R. Struzik, Junichiro Hayano, Yoshiharu Yamamoto, Yoshiharu Yamamoto, Proceedings of SPIE - The International Society for Optical Engineering,   2004年09月13日, Using the method of local Continuous Detrended Fluctuation Analysis (CDFA) we analyze the correlations of ventricular interbeat intervals of patients with Atrial Fibrillation (AF). CDFA yields a local Holder exponent h for a neighborhood around each point in the time series by determining the scaling of fluctuations with window size after detrending. We compare the histograms of Hölder exponents for original data with those of randomly shuffled data and find some correlations not only in long-range windows but also at short time scales where interbeat intervals during AF have been believed to be random in nature. Furthermore, we find unique temporal correlation structures to occur only in the heart rate of patients who were in the survivor group when a follow up was conducted at least one year after data acquisition. We conclude that ventricular interbeat intervals during AF contain richer information than previously considered and the study of the local correlations may be useful in predicting mortality of the patients.
  • Evidence for the origins and breakdown of 1/f noise in heart rate, Zbigniew R. Struzik, Zbigniew, R. Struzik, Junichiro Hayano, Seiichiro Sakata, Shin Kwak, Yoshiharu Yamamoto, Yoshiharu Yamamoto, Proceedings of SPIE - The International Society for Optical Engineering,   2004年09月13日, We present the first systematic evidence for the origins and breakdown of I/f scaling in human heart rate. We confirm a previously posed conjecture that I/f scaling in heart rate is caused by the intricate balance between antagonistic activity of sympathetic (SNS) and parasympathetic (PNS) nervous systems. We demonstrate that modifying the relative importance of either of the two branches leads to a substantial decrease of I/f scaling. In particular, the relative PNS suppression both by congestive heart failure (CHF) and by the parasympathetic blocker atropine results in a substantial increase in the Hurst exponent H and a shift of the multifractal spectrum f(α) from 1/f towards random walk scaling 1/f2. Surprisingly, we observe a similar breakdown in the case of relative and neurogenic SNS suppression by primary autonomic failure (PAF). Further, we observe an intriguing interaction between multifractality of heart rate and absolute variability. While it is generally believed that lower absolute variability results in monofractal behaviour, as has been demonstrated both for CHF and the parasympathetic blockade, in PAF patients we observe conservation of multifractal properties at substantially reduced absolute variability to levels closer to CHF. This novel and intriguing result leads us to the conjecture that the multifractality of the heart rate can be traced back to the intrinsic dynamics of the parasympathetic nervous system.
  • Proceedings of the 3rd Japanese Annual Conference on Chronocardiology and Hypertension: Preface, Hiroshi Hayashi, Junichiro Hayano, Clinical and Experimental Hypertension,   2003年04月01日
  • Increased serum triglyceride clearance, unchanged cholesteryl ester transfer protein activity, and elevated HDL cholesterol during treatment of hypertriglyceridemia with bezafibrate, Reiko Ikeuchi, Nagahiko Sakuma, Takeshi Hibino, Takaaki Sato, Yoshinobu Kamiya, Masanobu Kawaguchi, Nobuyuki Ohte, Junichiro Hayano, Current Therapeutic Research,   1994年01月01日, The effects of bezafibrate on lipid metabolism were evaluated in 22 patients with type IIb or type IV hypertriglyceridemia. Bezafibrate 400 mg/d was administered for 8 weeks. A fat emulsion tolerance test (FETT) to evaluate serum triglyceride (TG) clearance (fractional removal rate = K2) and measurement of cholesteryl ester transfer protein (CETP) activity were performed before bezafibrate administration and after the 8-week treatment period using blood samples obtained after overnight fasting. Statistically significant reductions were observed in serum TG (P < 0.01), apolipoprotein (apo) B (P < 0.01), apo C-II (P < 0.05), apo C-III (P < 0.001), and apo E (P < 0.05). Significant increases were seen in high-density lipoprotein cholesterol (HDL-C) (P < 0.001), apo A-I (P < 0.001), and apo A-II (P < 0.001). K2was significantly elevated (P < 0.001). CETP activity declined slightly, but the change was not statistically significant. Strong positive correlations were evident between the absolute value of increased K2and the increase in both HDL-C (r = .67, P < 0.005) and apo A-I (r = .53, P < 0.05). It can be inferred from these findings that the bezafibrate-induced reduction in serum TG and increase in HDL-C observed in patients with hypertriglyceridemia arise from an acceleration in TG-rich lipoprotein metabolism. © 1994 Excerpta Medica, Inc. All rights reserved.

特許

  • CVHR形状測定装置, 早野 順一郎, 特願2015-049863, 特開2016-168188
  • 睡眠解析装置及びプログラム並びに記録媒体, 木村 禎祐, 西井 克昌, 早野 順一郎, 特願2001-099985, 特開2002-291710, 特許第4731031号
  • 睡眠時無呼吸症診断装置, 大崎 理江, 木村 禎祐, 早野 順一郎, 塩見 利明, 特願2000-351713, 特開2002-153432, 特許第4693228号
  • 脈拍変動解析装置, 木村 禎祐, 西井 克昌, 早野 順一郎, 特願2001-140180, 特開2002-330935, 特許第4679755号
  • 睡眠呼吸障害の無呼吸発作又は低呼吸発作に伴うCVHRの検出装置, 早野 順一郎, 特願2008-217131, 特開2010-051387
  • 血管内皮機能検査装置, 早野 順一郎, 小椋 敏彦, 特願2002-300013, 特開2004-129979, 特許第4187498号
  • 心電図に基づく発作性心房細動の検出・評価システム, 早野 順一郎, 特願2002-171136, 特開2004-016248, 特許第3806371号
  • 血管内皮機能検査装置, 早野 順一郎, 小椋 敏彦, 特願2002-300013, 特開2004-129979
  • 心電図に基づく発作性心房細動の検出・評価システム, 早野 順一郎, 特願2002-171136, 特開2004-016248
  • 生体異常監視装置、血圧監視装置、生体異常監視方法、及び血圧監視方法, 西井 克昌, 難波 晋治, 木村 禎祐, 竹内 聡, 早野 順一郎, 特願2002-024056, 特開2003-047601
  • 脈拍変動解析装置、脈拍変動解析方法、プログラム、及び記録媒体, 木村 禎祐, 西井 克昌, 早野 順一郎, 特願2001-140180, 特開2002-330935
  • 睡眠解析装置及びプログラム並びに記録媒体, 木村 禎祐, 西井 克昌, 早野 順一郎, 特願2001-099985, 特開2002-291710
  • 睡眠時無呼吸症候群の診断方法, 大崎 理江, 木村 禎祐, 早野 順一郎, 塩見 利明, 特願2000-351713, 特開2002-153432

受賞

  •   2017年, 第37回ホルター・ノンインベーシブ研究会, 優秀演題賞
  •   1990年, 日本心電学会, 第6回木村栄一賞


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