Predictors and Outcomes of Arrhythmia on Stage I Palliation of Single Ventricle Patients

BACKGROUND Arrhythmias are common in single ventricle patients though their effect on outcomes during stage I palliation (S1P) is unclear. OBJECTIVES The authors sought to study associated risks for arrhythmia in patients undergoing S1P for single ventricle disease and evaluate the outcome of arrhythmias and their treatment strategies on survival. METHODS Retrospective patient, surgical, medication, and arrhythmia data were obtained from the NPC-QIC (National Pediatric Cardiology Quality Improvement Collaborative) database. Bivariate analysis of variables associated with arrhythmias, as well as those associated with survival, was performed at the time of stage II palliation. Appropriate variables were included in multivariate modeling. RESULTS Of the 2,048 patients included in the study, 36% had arrhythmia noted during their S1P hospitalization, with supraventricular tachycardia (12%) and focal atrial tachycardia (11%) the most common. At S1P discharge, 11% of patients were on an antiarrhythmic medication. Arrhythmias were associated with lower survival and increased hospital length of stay. Heterotaxy syndrome, younger age at S1P, male sex, and additional anomalies were associated with increased risk of arrhythmia in multivariable modeling (P <= 0.01). Arrhythmia and female sex were associated with increased mortality, whereas antiarrhythmic medication and digoxin use were associated with decreased mortality (P <= 0.003, model area under the curve 1/4 0.79). The use of antiarrhythmic medications within the subcohort of arrhythmia patients was also associated with decreased risk of mortality (P < 0.0001; odds ratio: 2.0-7.2). CONCLUSIONS Arrhythmias are common during admission for S1P and associated with poor outcomes. The use of antiarrhythmic medications may improve survival, though future studies are needed.