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.