Impact of renal transplantation on uremic cardiomyopathy

In chronic uremia, cardiomyopathy manifests itself as systolic dysfunction, concentric left ventricular (LV) hypertrophy, or LV dilatation. To determine the impact of renal transplantation on uremic cardiomyopathy, all dialysis patients participating in a long-term cohort study who received a successful renal transplant were followed with echocardiography. The transplanted group comprised 102 of 433 (24%) endstage renal disease (ESRD) patients. They were significantly younger and, on starting ESRD therapy, had significantly less ischemic heart disease and cardiac failure than the overall ESRD cohort. During followup, ischemic heart disease developed in only 1 patient and none experienced cardiac failure. In the 12% (n = 12) of patients with systolic dysfunction before renal transplant, fractional shortening normalized in all patients, increasing from 21.5 +/- 4.6% to 33.5 +/- 5.6% after transplantation. In the 41% (n = 41) with concentric LV hypertrophy before transplantation, the LV mass index improved from 158 +/- 39 g/m2 to 132 +/- 39 g/m2. LV dilatation was present in 32% (n = 32) of patients before transplantation. After transplantation, LV volume fell from 116 +/- 3.1 ml/m2 to 89 +/- 21 ml/m2, and LV mass index in this group fell from 166 +/- 55 g/m2 to 135 +/- 37 g/m2. It was not possible to associate risk factors characteristic of the uremic state with the improvement in cardiac structure and function, although the fall in LV mass was significantly associated with fall in blood pressure. We conclude that correction of the uremic state by renal transplantation leads to normalization of LV contractility in systolic dysfunction, regression of hypertrophy in concentric LV hypertrophy, and improvement of cavity volume in LV dilatation. The degree of improvement suggests that dialysis patients with uremic cardiomyopathy would benefit from renal transplantation.