Six-channel ECG-based pulse wave velocity for assessing whole-body arterial stiffness

Abstract

Background. Despite the proposal of different means of non-invasive arterial stiffness assessment, none offers simultaneous information on whole-body peripheral arterial condition. We investigated the validity of applying a six-channel electrocardiogram-based pulse wave velocity (ECG-PWV) measurement system for this purpose. Methods. The study consisted of two parts. Part One enrolled hypertensive (Group 1, n = 32) and normal (Group 2, n = 32) subjects, whereas Part Two recruited diabetic (Group 3, n = 50) and normal (Group 4, n = 50) subjects. To validate the application of ECG-PWV in assessing peripheral arterial stiffness in different parts of body, ECG-PWV data were compared with three other parameters including the cardio-ankle vascular index (CAVI), pulse wave velocity–digital volume pulse (PWV-DVP) and intima-media thickness (IMT). Results. ECG-PWV in healthy subjects in Part One correlated significantly with CAVI and PWV-DVP (p < 0.05), whereas ECG-PWV and CAVI were significantly different between the hypertensive and normal subjects. Moreover, comparison of IMT and ECG-PWV from different sites showed significant correlation only between IMT and ECG-PWV from earlobe (r = 0.495, p = 0.004). No significant association, however, was noted between IMT and CAVI. For Part Two, significant differences existed between diabetic and normal subjects in body weight, waist circumference, level of HbA1c, fasting blood sugar, serum creatinine and ECG-PWV from the foot. However, no significant difference was noted in PWV-DVP between two groups. Conclusions. Six-channel ECG-PWV measurement system showed remarkable correlation with IMT in hypertensive subjects and with key anthropometric and biochemical parameters in diabetic patients, suggesting its validity in assessing whole-body arterial stiffness in subjects with peripheral arterial diseases within 10 min.