Dynamics of changes in heart conduction system in dialyzed young adults after kidney transplantation--pilot study

Cardiovascular complications are the main clinical problem in patients with end-stage renal failure (ESRF). After successful kidney transplantation, this situation improves, although cardiovascular complications remain a risk factor for increased mortality in these patients; therefore, their early identification is of key therapeutic and prognostic significance. This study was designed to determine a dynamics of changes in the heart conduction system in hemodialyzed young adult patients after kidney transplantation in a long-term follow-up, based on the body surface potential mapping (BSPM) method.

The study comprised 5 patients (mean age, 20.8 ± 1.16 years) after kidney transplantation (KT) who had been chronically dialyzed before. The mean observation period was 6.7 ± 1.71 years. All of the patients were submitted to the following examinations before and after KT: 12-lead electrocardiography (ECG), echocardiography, standard biochemistry, and BSPM (isochronous maps). The mean creatinine concentration was 1.38 ± 0.05 mg/dL. The control group comprised 30 healthy persons.

BSPM maps taken from the dialyzed patients demonstrated disturbed spreading of electric impulses within the heart ventricles in a type of left bundle branch block, despite normal 12-lead ECG and echocardiography results. A relationship was demonstrated between the BSPM changes and dialysis duration. After KT, the abnormal distribution of isochrones and ventricular activation times (VAT) presented some significant and specific regression.

1) In dialyzed patients, BSPM is a more sensitive method than ECG and enables early identification of changes in the heart conduction system presented as left bundle branch block. 2) Dialysotherapy duration before and after KT determines the extent of the BSPM changes. 3) Successful effects of KT bring about regression of intraventricular conduction disorders. 4) The observations need verification in a larger patient group.