Incidence of Cardiac Arrhythmias in Chronic Renal Failure, Especially during Hemodialysis

Dr. S.C. Chhabra, Professor (Addl.) of Nephrology, Department of Medicine, New Dayanand Hospital, Ludhiana, Punjab (India) Dear Sir, With great interest we read the article by Kimura et al. [1] discussing the incidence and causative factors of cardiac arrhythmias in patients on maintenance hemodialysis. A number of studies to define the same have been published previously [2–5]. We have conducted a similar study and would like to present our findings so as to compare our observations with the study quoted above. Holter monitoring was done in 25 patients with chronic renal failure over a period of 24 h beginning the night before dialysis. Monitoring was extended till 4 h after dialysis. The incidence of ventricular and supraven-tricular arrhythmias analysed by sub-grouping into frequent, sporadic, and non-arrhythmia groups (as taken by the previous investigators) is compared in figure 1. Contrary to the observations of Kimura et al., both ventricular and supraventricular arrhythmias were infrequent in our cases, nor did hemodialysis precipitate arrhythmias in these cases. The only patient with frequent ventricular premature depolarizations (VPDs) had precipitation during dialysis, and of the 3 with supraventricular premature depolarizations (SVPDs), only 1 had more frequent SVPDs during dialysis. In fact, the patient with frequent ventricular arrhythmias had been known as having ischaemic heart disease and had undergone coronary bypass 5 years ago. Our observations suggest that arrhythmias may not be a causative factor in dialysis-induced hypotension. In fact, arrhythmias were not observed in any of the 5 episodes of hypotension during hemodialysis. Another interesting observation in our study was the occurrence of marked sinus tachycardia late during dialysis (3rd and 4th h) which persisted till 4 h after dialysis. This sinus tachycardia, as shown in figure 2, correlated