Cardiovascular factors influencing survival in end-stage renal disease treated by continuous ambulatory peritoneal dialysis

Abstract

To determine whether hemodynamic advantages of continuous ambulatory peritoneal dialysis (CAPD) over intermittent hemodialysis are associated with improved survival and identify cardiac risk factors for early death, 55 patients on CAPD (age 58 ± 11 years; CAPD duration: 29 ± 25 months) were followed in a noninvasive prospective analysis over 35 months. At follow-up, 25 patients had died; 16 deaths were related to cardiovascular causes. Nonsurvivors were older (62 ± 8 vs 55 ± 12 years; p < 0.015) and had more angina pectoris (40 vs 20%; p < 0.05) than survivors, but had comparable CAPD duration, arterial blood pressure, hemoglobin, serum creatinine, urea and parathyroid hormone concentrations. On echocardiography, nonsurvivors had a lower mean left ventricular (LV) ejection fraction (59 ± 15 vs 66 ± 9%; p < 0.03), higher LV end-systolic volume indexes (49 ± 31 vs 36 ± 13 ml/m²; p < 0.03) and a shorter mean LV ejection time (371 ± 41 vs 390 ± 22 ms; p < 0.03). LV muscle mass, LV diastolic and left atrial dimensions, stroke volume and cardiac index were comparable. On pulsed Doppler analysis of a subgroup of 48 patients in sinus rhythm and without valve disease, nonsurvivors (n = 23) had more severely decreased ratios of peak early/atrial filling velocities (0.66 ± 0.18 vs 0.81 ± 0.24; p < 0.03) and increased atrial filling fractions (52 ± 11 vs 46 ± 9%; p < 0.03) than survivors. Mean isovolumlc relaxation periods were increased in both groups (135 ± 39 vs 129 ± 33 ms; p > 0.05). These data suggest that older age, and reduced LV systolic and diastolic functions are attributed to increased mortality in patients with CAPD, whereas a significant influence of LV muscle mass and CAPD duration is not.