Method to Quantify Hypertension, Aging Status and Vascular Properties in Vivo from Arterial Optical Plethysmograph Waveform Measurements

摘要

The invention is an in vivo non-invasive method and apparatus for the measurement of hypertensive and aging status of a subject and the mechanical anelastic in vivo properties of arterial blood vessels. The method includes measuring a peripheral arterial pulse volume waveform (PVW) using an infra-red emitter and sensor positioned over an extremity and constructing the first time derivative, dPVW, of the PVW. From a ratio of the fall time over rise time of the dPVW and the time location of the second forward pulse wave, a hypertension index is derived. From the hypertensive index, the mechanical anelastic properties of peripheral arterial vascular vessels are determined. The change in the damping of the high frequency shear waves produces vasodilation/vasocontraction index which is a quantitative indicator of the extent of vasodilation, vasocontraction, or induced hypertension. From the index value the mechanical properties of arterial blood vessels are determined.