Pulse wave analysis on fingertip arterial pressure: effects of age, gender and stressors on reflected waves and their relation to brachial and femoral artery blood flow

Abstract

Analysis of the contour of the arterial pressure pulse (pulse wave analysis; PWA) adds information about arterial stiffness etc., beyond that obtained from absolute pressures. Peripheral pulses normally show an anterograde systolic peak and two reflected peaks: one in systole and one in diastole. The amplitudes and timings of these were estimated from finger pressure recordings in three study groups. We studied the usefulness of continuous digital pressures for PWA. First, PWA from intra-arterial (brachial) and non-invasive finger pressure recordings was compared. Secondly, stress-induced (mental arithmetics and cold pressor test) changes in pressure pulse reflection were compared with blood flow changes in brachial and femoral arteries (ultrasound). Thirdly, the influence of age and gender on digital pulse pressures was investigated at rest and during exercise. Pulse wave analysis results from brachial and digital pressures correlated strongly. Stress induced changes in systolic reflection were associated with changes in brachial artery flow patterns, whereas diastolic reflection was associated with femoral artery flow changes. At rest, age increased systolic reflection without affecting diastolic reflection. Exercise increased systolic reflection and reduced diastolic reflection more in older subjects (>40 years) than in younger (<40 years). In conclusion, PWA from continuous, digital pressure recordings is a convenient technique to study the arterial function at rest and during exposure to stressors in broad populations. The two reflected waves are differently regulated, which may indicate different anatomical origin.