Association of risk factors with increased pulse wave velocity detected by a novel method using dual-channel photoplethysmography.

BACKGROUND Pulse wave velocity (PWV) is correlated with cardiovascular risk. This study presents a new method for measuring the arterial PWV by simultaneously recording the digital volume pulse through the finger and the toe by way of dual-channel photoplethysmography (PPG). METHODS In this study, 100 asymptomatic subjects (54 men and 46 women, 19 to 64 years of age) were enrolled. The PWV was measured both by dual-channel PPG (PWV-DVP) and by the standard method that current used applanation tonometry (PWV-AT). The developed dual-channel PPG system recorded digital volume pulse simultaneously from both the finger and toe. Time of pulse transition was measured on the time delay difference between two digital volume pulses. The PWV was calculated by dividing the distance between finger and toe by that of transit time. RESULTS The PWV-DVP was significantly correlated with PWV-AT (r = 0.678, P < .01). With multivariate analysis controlled for age, heart rate, systolic blood pressure, and diastolic blood pressure, PWV-DVP was still significantly correlated with PWV-AT (r = 0.669, P < .01). Subjects with hypertension and dyslipidemia had significant higher PWV detected by both methods. CONCLUSION This study showed that PWV measured with dual-channel PPG system correlated very well with that measured using the traditional method.