Cardiac arrhythmias and silent myocardial ischemia in chronic renal failure patients on hemodialysis

ABSTRACT

Cardiovascular diseases are the most common cause of death in patients with End Stage Renal Disease [ESRD] on renal replacement therapy. Cardiac arrhythmias are frequent cardiovascular complication during dialysis session. ST segment depression on ambulatory ECG without patient awareness is a marker of what has been termed "silent ischemia". It has been suggested that in patient with ESRD transient ST segment depressions are associated with increased cardiovascular mortality. The objective of this study is to evaluate and to detect the effect of hemodialysis on cardiac rhythm in ESRD patients on regular hemodialysis by using Holler's monitor [24 hours. ambulatory electrocardiogram] and also to detect prevalence of silent myocardial ischemia among these patients. This study was conducted in the Dialysis Unit, Sohag University Hospital, Sohag Faculty of Medicine. It included 40 adult patients [29 males and 11 females] with ESRD on regular hemodialysis. Their ages ranged from 18-50 years with a mean age of [35 +/- 2.36] years. Results of this study showed that there is runs of ventricular and supraventricular arrhythmia in dialysis patients and the occurrence of this arrhythmia in the form of insignificant ventricular runs which occurred in 2 [5%] out of 40 patients studied. However there is a significant prevalence of total ventricular arrhythmia which occurred in 80% of the patients. There is significant occurrence of supraveniricular arrhythmia which occurred in 62.5%, 42.5% and 40% [predialysis, during dialysis and postdialysis respectively]. Ventricular tachycardia was not seen, and supraventricular was observed in 5 patients [12.5%]. The total number of these arrhythmias [both ventricular and supraventricular] were improved by hemodialysis. The present study showed that there is a high incidence of myocardial ischemic episodes in relation to hemodialysis. 29 [72.5%] out of 40 patients showed ischemic episodes of whether 24 [83%] patients showed asymptomatic ischemic episodes. The study also showed that most ischemic episodes whether painful or silent were recorded during hemodialysis session [72.8%]. Dialysis per se is not arrhythmogenic. The isolated ventricular and atrial arrhythmias occurred in patients with ESRD cluster before next hemodialysis sitting are assumed to be due to disturbances of both serum phosphorus and serum potassium levels. On the other hand myocardial ischemic episodes frequently occurred during hemodialysis