Asystole episodes and bradycardia in patients with end-stage renal disease

Background Knowledge of arrhythmias in patients with end-stage renal disease (ESRD) is mainly based on ambulatory electrocardiography (ECG) studies and observations during haemodialysis. We used insertable cardiac monitors to define the prevalence of arrhythmias, focusing on bradyarrhythmias, in ESRD patients treated with several dialysis modes including home therapies. Moreover, we assessed whether these arrhythmias were detected in baseline or ambulatory ECG recordings. Methods Seventy-one patients with a subcutaneously insertable cardiac monitor were followed for up to three years. Asystole (≥4.0 secs) and bradycardia (heart rate <30 bpm for ≥4 beats) episodes, ventricular tachyarrhythmias and atrial fibrillation were collected and verified visually. A baseline ECG and a 24-48-hour ambulatory ECG were recorded at recruitment and once a year thereafter. Results At recruitment, forty-four patients were treated in in-center haemodialysis, 12 in home haemodialysis and 15 in peritoneal dialysis. During a median follow-up of 34.4 months, 18 (25.4%) patients had either an asystolic or a bradycardic episode. The median length of each patient’s longest asystole was 6.6 seconds and that of a bradycardia 13.5 seconds. Ventricular tachyarrhythmias were detected in 16 (23%) patients, and atrial fibrillation in 34 (51%) patients. In-center haemodialysis and type II diabetes were significantly more frequent among those with bradyarrhythmias whereas no bradyarrhythmias were found in home haemodialysis. No bradyarrhythmias were evident in baseline or ambulatory ECG recordings. Conclusions Remarkably many patients with ESRD had bradycardia or asystolic episodes, but these arrhythmias were not detected by baseline or ambulatory ECG.