IMPACT OF HEMODIALYSIS ON COMREHENSIVE VENTRICULAR REPOLARIZATION

Abstract

Cardiac arrhythmia is a very important cause of mortality in chronic renal failure patients on regular hemodialysis. QT dispersion is a good marker that can predict arrhythmic events and sudden death. In this study we have tried to detect the relation between chronic hemodialysis and arrhythmia by monitoring the effect of dialysis on QT dispersion. Also we have tried to find out if standard 12 leads of ECG are sufficient to have a complete idea about ventricular repolarization or it is a must to use full ECG leads including right sided leads and extra left sided leads. Our study included 35 patients on maintenance hemodialysis , 22 males (63%) and 13 females(27%),their age ranged between 20 and 63 years, with mean age 41 ±2.27. Patients with ischemic heart disease, congenital heart disease,pericardial disease like pericarditis or pericardia! effusion, patients with rhythm or conductive disorder and patients taking antiarrhythmic drugs, all were excluded. They were subjected to the following: -full history analysis. -clinical examination including body wt., BP (pre and post dialysis) and for detection and exclusion of cardiac lesions. -laboratory estimation of serum BUN, creatinine, sodium, potassium, and calcium pre and post-dialysis. -ECG was done to all patients just pre-dialysis and 45 min post­ dialysis, at a speed of 25mm/sec. Standard 12 lead ECG, right ventricular leads (RV3•6), left ventricular posterior wall leads (V7•8•9).Leads were divided into 3 groups: group A (standard 12 ECG leads),group B(Right side leads),group C (All the leads). The duration of repolarization parameters: QT, JT, QTc, JTc,was measured in all leads manually in all groups, before and after dialysis. Dispersion of repolarization parameters: QTd, QTcd, JTd, JTcd was measured in all groups before and after dialysis. Mean predialysis body weight was 57. 7 ± 14.1Kg,mean Postdialysis body weight was 56.9 ± 12Kg ( with non-significant change).