Reliability of noninvasive methods to measure cardiac autonomic function.
Cardiac autonomic modulation was examined in 10 healthy subjects (mean age = 27.8 +/- 1.7) at rest (paced breathing at 12 and 16 breaths/min) and during a submaximal cycle ergometer exercise test. Heart rate variability (HRV) spectral parameters and spontaneous baroreflex (SBR) function variables showed no significant differences between mean values for any of the testing conditions. Spectral parameters and SBR function did not differ significantly between the resting conditions. Significant reliability coefficients (r = 0.59-0.73) were observed for all spectral parameters except low frequency power (r = 0.22) during 12 breaths/min, with moderately lower values during 16 breaths/min (r = 0.10-0.75) and exercise (r = 0.20-0.89). Significant reliability coefficients were observed for baroreflex sensitivity at 12 (r = 0.83) and 16 (r = 0.92) breaths/min. It was concluded that at rest, HRV spectral and SBR analyses are reliable methods for studying cardiac autonomic balance.
School of Physical and Health Education, Queen's University, Kingston, ON, Canada.
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Amara
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Wolfe
D000328:Adult; D000704:Analysis of Variance; D001341:Autonomic Nervous System / Q000502:physiology*; D017704:Baroreflex / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology; D005080:Exercise Test; D005260:Female; D006329:Heart Conduction System / Q000502:physiology*; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008991:Monitoring, Physiologic; D010101:Oxygen Consumption / Q000502:physiology; D005082:Physical Exertion / Q000502:physiology; D012044:Regression Analysis; D015203:Reproducibility of Results; D012119:Respiration / Q000502:physiology; D012146:Rest / Q000502:physiology; D012815:Signal Processing, Computer-Assisted; D013990:Tidal Volume / Q000502:physiology