Arrhythmias in Patients on Maintenance Dialysis: A Cross-sectional Study.

Rationale & Objective: Patients with kidney failure treated with maintenance dialysis experience a high rate of mortality, in part due to sudden cardiac death caused by arrhythmias. The prevalence of arrhythmias, including the subset that are clinically significant, is not well known. This study sought to estimate the prevalence of arrhythmias, characterize the pattern of arrhythmic events in relation to dialysis treatments, and identify associated clinical characteristics.

Study Design: Cross-sectional study.

Setting & Participants: 152 patients with kidney failure treated with maintenance dialysis in Denmark.

Exposures: Dialysis treatment; clinical characteristics; cardiac output and preload defined using echocardiography.

Outcomes: Prevalence and pattern of arrhythmias on 48-hour Holter monitoring; odds ratios for arrhythmias.

Analytical Approach: Descriptive analysis of the prevalence of arrhythmias. Pattern of arrhythmias described using a repeated-measures negative binomial regression model. Associations between clinical characteristics and echocardiographic findings with arrhythmias were assessed using logistic regression.

Results: Among the 152 patients studied, 83.6% were treated with in-center dialysis; 10.5%, with home hemodialysis; and 5.9%, with peritoneal dialysis. Premature atrial and ventricular complexes were seen in nearly all patients and 41% had paroxysmal supraventricular tachycardia. Clinically significant arrhythmias included persistent atrial fibrillation observed among 8.6% of patients, paroxysmal atrial fibrillation among 3.9%, nonsustained ventricular tachycardia among 19.7%, bradycardia among 4.6%, advanced second-degree atrioventricular block among 1.3%, and third-degree atrioventricular block among 2.6%. Premature ventricular complexes were more common on dialysis days, while tachyarrhythmias were more often observed during dialysis and in the immediate postdialytic period. Older age (OR per 10 years older, 1.53; 95% CI, 1.15-2.03; P=0.003), elevated preload (OR, 4.02; 95% CI, 1.05-15.35; P=0.04), and lower cardiac output (OR per 1L/min greater, 0.66; 95% CI, 0.44-1.00; P=0.05) were independently associated with clinically significant arrhythmias.

Limitations: Arrhythmia monitoring limited to 48 hours; small sample size; heterogeneous nature of the population, risk for residual confounding.

Conclusions: Arrhythmias, including clinically significant abnormal rhythms, were common. Tachyarrhythmias were more frequent during dialysis and the immediate postdialytic period. The relevance of these findings to clinical outcomes requires additional study.