Objectives: To assess the determinants of central pulse pressure (CPP) in end stage renal disease (ESRD), with special focus on respective roles of wave reflection, aortic stiffness and geometry (diameter) compared with controls (CT).

Methodology: 115 ESRD (49±15 years, SBP/DBP: 152±3/82±1 mmHg) were compared to 59 CT without renal insufficiency (46±13 years (NS), 143±3 (<0.02)/87±2 mmHg (NS)). Cardiac echography (stroke volume (StVl), aortic diameter), carotid artery wave analysis, aortic wave reflections (tonometry) and aortic pulse wave velocity (PWV) were measured, with calculation of characteristic impedance (Zc, dyne.s.cm⁻⁵). Multiple regression analyses were based on 2 models: M1: age, BP, cardiac function, AI% and Zc, and M2: age, BP, cardiac function, AI%, PWV and Aortic diameter (to assess determinants of Zc).

Results: Versus CT, ESRD had higher carotid pressures, heart rate, AI%, and PWV while aortic diameter was similar. Determinants of CPP in ESRD were age, MBP, cardiac StVl, AI% and Zc (M1 model: R²= 0.70, p<0.001), in CT: MBP, AI% and Zc (R²= 0.67, p<0.001). M2 model shows in ESRD: age, MBP, AI%, Aortic diameter and PWV (R²= 0.61, p<0.001). In CT, determinants were AI% and PWV (R²= 0.46, p<0.001) with no impact of aortic geometry.

Conclusion: Increased CPP is associated with increased arterial Zc and wave reflections. In controls, CPP is linked to stiffness and AI% only, and in ESRD: mainly stiffness and AI% plus minor impact of aortic geometry. In normal subjects and hypertensives without renal failure, CPP is determined by stiffness and reflection, but not by aortic geometry.