Mitral Valve Calcification as an Index of Left Ventricular Dysfunction in Patients With End-Stage Renal Disease on Peritoneal Dialysis

Abstract

To determine whether mitral valve or anulus calcification (MC) in patients with end-stage renal disease is associated with abnormalities of left ventricular (LV) structure and function, cardiac characteristics of 55 patients undergoing continuous ambulatory peritoneal dialysis (CAPD) with (n = 26; age: 59 +/- 10 years) vs without (n = 29; age: 58 +/- 12 years) MC were analyzed using echocardiography and Doppler echocardiography. Sclerosis of the mitral valve anulus was detected in 18 (7 women, 11 men; age: 58 +/- 10 years) patients, sclerosis of mitral valve leaflets in 24 (13 women, 9 men; age: 59 +/- 10 years) patients. Patients with MC had higher systolic arterial blood pressure before initiation of dialysis therapy (191/104 mm Hg vs 173/94 mm Hg; p < 0.05) and higher calcium-phosphorus products (55 +/- 13 vs 42 +/- 16; p < 0.05) during CAPD therapy than those without MC. Neither prevalence nor severity of MC was related to dialysis duration or patient age. Systolic LV function was reduced (ejection fraction: 58 +/- 12 percent vs 65 +/- 13 percent; p < 0.05) and LV end-diastolic diameters were dilated (54 +/- 5 vs 50 +/- 8 mm; p < 0.05) in patients with MC. Left atrial dilatation (73 percent vs 31 percent; p < 0.005) and mitral valve regurgitation (65 percent vs 21 percent; p < 0.001) were more frequent in patients with vs those without MC. Excluding patients with significant mitral regurgitation from pulsed Doppler analysis, diastolic LV function was comparably impaired in patients with vs those without MC (maximal early/atrial filling velocity ratio: 0.77 +/- 0.25 vs 0.75 +/- 0.22; atrial filling fraction: 47 +/- 10 percent vs 48 +/- 11 percent; p = NS). The presented data suggest that MC follows long-standing and severe arterial hypertension before start of dialysis therapy. Therefore, effective blood pressure control in the predialysis period may be a tool to prevent these lesions. MC has clinical significance as a marker of LV dilatation and reduced LV systolic function in patients with chronic CAPD.