Central Artery Pulse Pressure in End-Stage Renal Disease: The Roles of Aortic Diameter, Aortic Stiffness and Wave Reflection

Abstract

In elderly subjects and patients with end-stage renal disease (ESRD), carotid pulse pressure (PP) is an independent and significant predictor of cardiovascular (CV) risk. Whereas in the elderly carotid diameter, but not carotid stiffness, is an associated CV risk factor, an opposite CV risk pattern was observed in ESRD patients that was associated with stiffness. Whether in ESRD patients arterial diameter, stiffness or both are involved in the mechanism(s) of increased carotid PP has never been investigated. Nondiabetic ESRD patients (n = 144) were compared with 57 control subjects matched for age, sex and mean blood pressure, but with higher brachial and carotid PP. Noninvasive echo-Doppler techniques and pulse wave velocity (PWV) and pulse wave analysis were used to evaluate cardiac and carotid arterial structures and functions using multiple stepwise regressions. In controls, carotid PP was associated only with stroke volume, arterial wave reflections and aortic PWV, but not aortic diameter. In ESRD patients, it was associated with wave reflections, aortic PWV, stroke volume and higher aortic diameter. In ESRD patients and controls, elevated carotid PP mainly reflected increased aortic PWV and earlier wave reflections. Aortic diameter had an impact only on ESRD patients, where it compensated for enhanced aortic stiffness and the more pronounced effect of reflected waves. This hemodynamic profile differs consistently from that in elderly subjects of the general population and selectively influences CV risk and drug treatment.