The Effect of Renal Transplantation on Ventricular Repolarization in Children with Chronic Renal Failure

BACKGROUND Chronic renal failure and hemodialysis affect many ECG parameters which can affect cardiac repolarization. OBJECTIVE To investigate the change in ventricular repolarization before and after kidney transplantation in children. METHODS A total of 45 children with end-stage renal disease, 45 children at least 6 months after successful renal transplantation, and 45 normal age-matched subjects were enrolled into this study. A 12-lead ECG was recorded in the 3 groups. QT dispersion, QTc dispersion, and T peak to T end (TPE) dispersion were measured. RESULTS In the patients before and after renal transplantation and the normal children, respectively, the mean±SD QT dispersion was 0.083±0.033, 0.056±0.029, and 0.033±0.016 (p<0.01); the mean±SD QTc dispersion was 0.104±0.038, 0.066±0.033, and 0.039±0.020 (p<0.01); the mean±SD TPE interval dispersion was 0.060±0.021, 0.045±0.021, and 0.034±0.019 (p<0.01). There was a significant correlation between left intra-ventricular diastolic diameter and QT dispersion, QTc dispersion, and TPE dispersion. The systolic velocity of the mitral valve also correlated with TPE dispersion (r=0.44, p=0.01). CONCLUSION In children with chronic renal failure, indices of ventricular repolarization improve after transplantation, though they still remain longer than the normal values.