Role of pulse wave velocity for assessing autonomic nervous system activities in reference to heart rate variability

Pulse wave velocity (PWV) is related to arterial wall elasticity, which in part is regulated by sympathetic nervous system activity. The present study investigated the potential for the simultaneous use of PWV and heart rate variability using noninvasive recordings in order to provide a quantitative evaluation of the sympathovagal interaction modulating cardiovascular functions. We obtained 10 indices from the PWV and heart rate (HR) time series of 92 healthy subjects (control group) and compared the results with those of 135 patients with diabetes mellitus or vertigo. Five indices were obtained from a PWV series, that is, the mean, the coefficient of variation (CV) during supine rest, those immediately after standing up unaided, and the change of the mean PWVs before and after standing. The rest of the indices were also obtained from the instantaneous HR series. Statistical analyses revealed significant differences in the change of the mean PWVs after standing, the mean and CV of resting HR, the mean and CV of standing HR, and the change of mean HRs in patients with diabetic neuropathy as compared with healthy subjects (P < 0.01). The change of the mean PWV immediately after standing allows for the assessment of peripheral vascular sympathetic functions, provided one uses HR variability indices simultaneously.