A Reliable Measurement to Assess Atherosclerosis of Differential Arterial Systems

Abstract

There are several assessments used to measure pulse wave velocity. We have ever designed an instrument to measure brachial-femoral pulse wave velocity by photoplethysmograpy with infrared sensors. This method is reliable and correlate with another instrument recorded with tonometry. Our method demonstrates the difference of velocity between brachial and femoral arteries. On some occasions, the measurement gets a false-negative result when the examinee has similar atherosclerotic changes of both brachial and femoral arteries. Therefore, we design a measurement to assess pulse wave velocities by the time difference between R wave of ECG and initiation point of the pulse wave. The infra-red sensors can be placed on the eardrops, fingertips or toes then measure pulse wave velocities in different arterial systems including carotid artery, brachial artery and femoral artery directly. These measurements also reflect atherosclerotic changes of aortic arch and descending aorta respectively. Although atherosclerosis is a systemic disorder, patients sometimes get various involvements in different regions of the arterial tree. In this study, 33 healthy adults (25 males and 8 females) are enrolled. They received measurement of pulse wave velocity by our new method and brachial-femoral pulse wave velocity. There is the statistically significant correlation between this new method and brachial-femoral pulse wave velocity (r=0.453, p<0.01). In the mean time, the new assessment shows the pulse wave velocities are different in carotid, brachial and femoral arterial system. The ratio of the speeds is 1:2:3, which relates to diameters of these vessels inversely. This finding is fit the continuity equation, Q=AV, in hydraulics.Herein, we demonstrate a new method, which can be used to measure pulse wave velocity in different arterial systems. This method is reliable and reproducible. In addition to be applied in assessment of aortic stiffness, it can also be used to evaluate atherosclerosis of different arterial systems.KeywordsPWVECGcardiovascular diseases