Arterial pulse in health and disease

Abstract

Arterial stiffness exerts a major influence on cardiac afterload and coronary perfusion. Indices of arterial stiffness have therefore been proposed as surrogate markers of cardiovascular risk and as a potential therapeutic target. A description of arterial stiffness in both healthy and diseased populations and an understanding of the variables that affect it is an essential prelude to further work in this area. Therefore, I applied the techniques of pulse wave analysis to measure augmentation index (AI%), an index of wave reflection in the ascending aorta with measurement of pulse wave velocity (PWV) in 25% of cases, to 416 individuals (aged 16-86 years, 228 healthy, 188 untreated hypertensive patients). AI% and PWV were correlated (r = 0.62, n=130, p<0.001). In the older hypertensive subjects, heart rate and height and diastolic blood pressure (DBP) and gender in the younger normotensive population were the major determinants. For PWV, age and systolic blood pressure were the principal determinants in both normotensive and hypertensive subjects. Also, PWV was significantly higher in males, while AI% was higher in females. The aortic systolic blood pressure (SBP) was significantly higher in the young males compared to females but was the same in both sexes in the hypertensive group. Pulse pressure (PP) amplification, which was higher in males than females had a stronger inverse relationship to AI% than PWV and was significantly reduced in the hypertensive compared to the healthy subjects. I identified a group of healthy young individuals who had pseudo-systolic hypertension, a state of elastic arteries with markedly increased PP amplification, giving rise to a normal aortic but elevated brachial SBP. These individuals were all male, non-smokers and active sportsmen.