Elevated plasma B-type natriuretic peptide (BNP) predicts future cardiovascular events in dialyzed patients without heart failure. We investigated whether carvedilol reduces the elevated BNP in these patients. Asymptomatic patients on chronic hemodialysis with elevated BNP but without clinical signs of heart failure were randomly assigned to receive either carvedilol (n = 10) or nothing (control group, n = 10). BNP and malondialdehyde-low density lipoprotein (MDA-LDL) were measured, and ultrasound cardiography was performed at baseline and at 3 months. Carvedilol reduced the concentrations of BNP (551 +/- 90 to 237 +/- 174 ng/L, P < 0.01) and MDA-LDL (174 +/- 63 to 85 +/- 23 U/L, P < 0.01) and increased the velocity ratio of E to A waves of the transmitral flow (E/A: 0.59 +/- 0.04 to 0.71 +/- 0.05, P < 0.05), while no such alterations were observed in the control group. The reduction in BNP concentration was correlated with that in MAD-LDL and the increase in the E/A. There was a significant correlation between the increase in the E/A and the reduction in MDA-LDL concentration. Thus, carvedilol reduces the elevated BNP by improving left ventricular diastolic function in dialyzed patients without heart failure, which may be attributable to the antioxidant property of the beta-blocker. Administering carvedilol may improve the prognosis in this population.