AORTIC AND LARGE ARTERY COMPLIANCE IN END-STAGE RENAL-FAILURE

Pulse wave velocity (PWV) was measured in the aorta, right leg and arm of 90 control subjects (CS) and 92 hemodialysis patients (HD) of the same age and mean arterial pressure (MAP). Blood chemistry, including blood lipids, and echographic dimensions of the aorta, were measured in all subjects. Presence of aortic calcification was evaluated by abdominal X-ray and echography. Whereas femoral and brachial PWV were only slightly increased in HD (P < 0.05), the aortic PWV was significantly elevated (1113 ± 319 cm/sec) in comparison with CS (965 ± 216 cm/sec; P = 0.0016). Aortic diameters were larger in HD, both at the root of aorta (32.7 ± 4 vs. 28.2 ± 2.8 mm; P < 0.0001) and aortic bifurcation (16.9 ± 3.1 vs. 14.6 ± 2.2 mm; P < 0.0001). Although the MAP was similar in HD (109.9 ± 19.3 mm Hg) and CS (110.2 ± 17.2 mm Hg), the pulse pressure was significantly increased in HD patients (76.6 ± 23.7 vs. 63.9 ± 22 mm Hg; P = 0.007). In the two populations, aortic PWV was found to increase with age (P < 0.0001) and MAP (P < 0.0001). The presence of aortic calcification showed only a borderline relationship with the increase in aortic PWV (P = 0.050 in CS and P = 0.069 in HD). As change in PWV is directly related to change in distensibility, and the aortic diameters were increased in HD, these results indicate that aortic wall compliance is decreased in HD, resulting in an increase in the pulsatile component of arterial pressure. Alteration of pulsatile arterial dynamics contributes to an increase in left ventricular load and is significantly related to the left ventricular hypertrophy which is frequently observed in these patients (P < 0.001).