Patients with end-stage kidney disease untergoing chronic maintenance dialysis (HD) are a high risk group for sudden death due to cardiovascular complications. It was the aim of the study to investigate the quantity and quality of arrhythmias during HD and between two consecutive HD (interval, I) with regard to the reproducibility of the expected results. 15 patients (8 males, 7 females) underwent continuous Holier monitoring (LT-ECG) under ambulatory conditions over 96 h including two HD (HD 1 + HD2) and two intervals (11 + 12). The LT-ECG recordings were analysed with the computer assisted ‘Multipass-Scanning’ system with regard to heart rate (HR), supraventricular premature beats (SPB), ventricular ectopics (PVC) and malignant ventricular arrhythmias. Results: The HR demonstratd a typical, well-known circadian pattern with remarkable increase of the HR during each HD. Except for rare, single SPB and/or PVC, no supraventricular or ventricular arrhythmias could be detected reproducibly. Single PVC occurred in patients with a lower potassium value. No malignant ventricular arrhythmias were found. In comparison to previously published studies, which demonstrated a high incidence of malignant ventricular arrhythmias, these conflicting results were due to differences in patients’ recruitment (unterlying disease, age, etc.), the performance of HD (duration, ion concentration of the dialysate etc.), serum potassium levels and drug medication (digitalis, quinidine). In summary, chronic HD per se did not enhance the risk of malignant arrhythmias in patients with end-stage kidney di