EFFECTS OF HEMODIALYSIS ON BODY-SURFACE MAPS IN PATIENTS WITH CHRONIC-RENAL-FAILURE

To examine the effects of hemodialysis on the electrocardiogram, 87-le ad body surface maps were performed in 38 patients with chronic renal failure, before and after hemodialysis. The patients were divided into two groups; 16 patients with coronary artery disease (CAD group), and 22 patients without ischemic heart disease (control group). Three map s were analyzed, QRS isopotential maps, isochrone maps, and QRS isoint egral maps. Parameters measured were maximal R wave voltage (Peak R), minimal QRS wave voltage (Peak S), maximal ventricular activation time (VAT(max)) and QRS duration (QRSd). In the control group, Peak R and Peak S increased but VAT(max) decreased after hemodialysis. There were negative correlations between the changes of body weight and the chan ges in Peak R (r = -0.67, p < 0.01) and Peak S (r = -0.87, p < 0.001), although there were no correlations between changes in left ventricul ar diastolic dimension and the changes in Peak R and Peak S. In the CA D group, Peak S increased but Peak R and VAT(max) did not change signi ficantly. There were negative correlations between the change of body weight and the change of Peak S (r = -0.73, p < 0.01). The most pronou nced changes in mean QRS isointegral maps on hemodialysis were an incr eased magnitude of positivity in the control group and negativity in t he CAD group on the anterior thorax. These findings suggested that the increase in the QRS amplitude after hemodialysis was influenced by th e changes of the conductivity of extracardiac thorax and the relative heart position to the chest wall rather than myocardial ischemia or ve ntricular conduction delay.