Noninvasive Estimate of Systemic Arterial Compliance by Using Peripheral Arterial Blood Pressure Waveform during Light Exercise in Elderly People

Systemic arterial compliance (SAC) for the aged is a very important index in hemodynamics during exercise. In this study, the blood pressure waveform used for calculation of SAC was noninvasively recorded at finger artery by volume clamp method (VC) and compared with the method recorded by applanation tonometry (AT) at carotid artery, and usefulness and validity of this method were investigated. Continuous blood pressure waveform was recorded using VC at finger artery and AT at carotid artery during the light exercise for 22 elderly patients. The blood pressure waveform by VC was transformed by transfer function into the waveform of brachial artery. The ratio of the subjects recorded with stable waveform was 64% by AT while that of VC is 100%. Significantly high correlationship (r=0.89) between the measured values of the ratio of the area under the arterial blood pressure waveform at one heart beat cycle and at left ventricular diastole by VC and AT was observed, and its agreement was very good. As a consequence, it is supposed to be valid to use the method using blood pressure waveform recorded at peripheral artery by VC as a noninvasive estimate method of SAC for the elderly people during light exercise.