| Abstrakt: |
Aortic distensibility (AoD) is markedly impaired in patients (pts) with chronic renal failure (CRF). Little is still known about the beneficial effect of hemodialysis (HD) on the AoD. We aimed at clarifying the magnitude of this beneficial effect in hypertensive and normotensive pts with CRF. Our study was consisted of 50 CRF pts (31 men, 19 women, aged 45 ± 14 years) undergoing regular HD. Twenty-eight pts were hypertensive (17 men, 11 women, aged 51 ± 14 years), controlled with antihypertensive treatment and without exceeding blood pressure over 160/95 mmHg as was detected by blood pressure Holter monitoring. The remaining 22 pts were normotensive (14 men, 8 women, aged 38 ± 11 years). AoD was calculated as a function of changes in aortic diameter and pulse pressure, using the formula: 2 × (pulsatile change in diameter)/([diastolic diameter] × [pulse pressure]). Aortic diameters were measured by transthoracic echocardiography, while arterial pressure was measured simultaneously by sphygmomanometry at the brachial artery. The 2 groups did not differ with respect to the prevalence of coronary risk factors other than hypertension, neither regarding body mass index, body weight before and after HD, ultrafiltration volume, EPO therapy, plasma fibrinogen, plasminogen, fibronectin, creatinine and calcium/phosphorus ratio values. AoDist was significantly lower in hypertensive compared with normotensive CRF pts both before (1.7 ± 0.7 vs. 2.2 ± 0.6 cm2 · dyn-1 · 10-6, p < 0.01) and immediately after completion of the HD session (2.1 ± 1.1 vs. 3.2 ± 0.9 cm2 · dyn-1 · 10-6, p < 0.001). A significant improvement of AoDist was noted in both groups of pts after HD; The magnitude of the improvement, however, was significantly greater in normotensive compared with hypertensive pts (0.9 ± 0.6 vs. 0.4 ± 0.5 cm2 · dyn-1 · 10-6, p < 0.001). Our findings show that HD has a less beneficial effect on the AoD of hypertensive CRF compared to that of normotensive ones. The improvement of AoD after HD, although likely passive in nature and possibly of limited duration, may however add considerably to the overall hemodynamic benefit offered by regular HD in CRF pts. |
