Arrhythmias Requiring ECMO in Infants Without Structural Congenital Heart Disease.

Arrhythmias account for 55 per 100,000 patient evaluations in pediatric emergency departments. Most arrhythmias in children are amenable to medical management or cardioversion. Rarely, arrhythmias lead to significant hemodynamic instability requiring extracorporeal membrane oxygenation (ECMO) support. This study seeks to evaluate children under 1 year of age with a structurally normal heart requiring ECMO for an arrhythmia. This is a retrospective review of the Extracorporeal Life Support Organization Registry. All patients less than 1 year of age between 2009 and 2019 with a diagnosis of arrhythmia and without a diagnosis of structural heart malformation were included. Demographics, clinical characteristics, and outcomes were assessed with descriptive statistics and univariate and multivariable analyses. A total of 140 eligible patients were identified from the dataset. The most common arrhythmia was supraventricular tachycardia (SVT) in 70 (50%) patients. ECMO complications occurred in 106 (76.3%) patients and survival to discharge was achieved in 120 (85.7%) patients. In-hospital mortality was associated with neuromuscular blockade prior to ECMO [aOR 10.0 (95% CI 2.95-41.56), p < 0.001], neurologic ECMO complication [aOR 28.1 (95% CI 6.6-155.1), p < 0.001], and race with white race being protective [aOR 0.13, (95% CI 0.02-0.21), p = 0.002]. Similar survival and complication rates were found in subgroup analysis of SVT arrhythmias alone. Arrhythmias necessitating ECMO support in infants without structural congenital heart disease is a rare occurrence. However, survival to hospital discharge is favorable at greater than 85%. Given the favorable survival, earlier and more aggressive utilization of ECMO may result in improved outcomes.