Cardiac consequences of renal transplantation changes in left ventricular morphology

The aim of this study was to characterize changes in left ventricular morphology and function by conventional echocardiography in a pediatric population after renal transplantation (RT).

This study includes 21 children, 11 female and 10 male, aged 11.8 +/-2.6 years at the time of renal transplantation. Eleven were on regular hemodialysis treatment and two on continuous peritoneal dialysis for 31.8 +/- 31.6 months; eight were transplanted without prior dialysis. Eight children were hypertensive before RT and nine (seven de novo) after RT. The patients were analysed in a prospective follow-up study with echocardiography immediately before and 30.2 +/- 15 months after successful renal transplantation. We measured the following echocardiographic parameters: Left ventricular end diastolic (LVED) and end systolic diameter (LVES), left atrial dimension (LAD), septal thickness (IVST), posterior wall thickness (PWT), shortening fraction (SF) and left ventricular index mass (LVIM). The paired Student's test, Fisher exact test and Pearson's correlation were used for statistical analysis. We analyzed the echocardiographic changes in the total group and separately in the subgroups with and without prior hemodialysis, as well as the influence of the duration of dialysis, anemia and hypertension.

1. After renal transplantation we found a decrease in the LVED LVES, LAD, IVST and PWT measurements (p < 0.05). There was a negligible increase in SF. The LVIM decreased from 139 g/m2 to 104 g/m2, representing a 21% reduction of the initial value, but this reduction was not of statistically significant. 2. The findings were similar in the hemodialysis group-LVIM decreased from 167.6 g/m2 to 94.9 g/m2, representing a 35% reduction in the initial value. 3. In the non dialysis group LVED, LVES, LAD and SVT decreased and LVIM showed a minor increase. There was a negligible increase in SF. 4. We found an increased LVIM in children with prior hemodialysis before RT, especially if dialysis lasted for more than two years. 5. Amelioration of hematocrit correlated with reduction of LVIM. 6. Regression of LV hypertrophy after RT was not dependent on blood pressure levels.

Renal transplantation resulted in a tendency towards normalization of the echocardiographic parameters analysed: Contractility, as assessed by shortening fraction, was normal in this population. Although cardiac hypertrophy and dilation is reversible after RT, it would seem that children may benefit from an earlier transplantation.