Intravenous to Oral Transition of Amiodarone (IOTA): Effect of Various Durations of Overlap on Atrial Fibrillation Recurrence After Cardiothoracic Surgery.

ABSTRACT: The use of amiodarone for postoperative atrial fibrillation (AF) is widespread; however, there is a paucity of data on the optimal duration of overlap when transitioning from intravenous (IV) to oral amiodarone. The objective of this study was to evaluate the safety and efficacy of varying durations of overlap when amiodarone IV infusion is transitioned to oral administration in cardiothoracic surgery patients. This retrospective, observational, single-center study included cardiothoracic surgery patients who were initiated on IV amiodarone for supraventricular arrhythmia and subsequently transitioned to oral amiodarone. The primary outcome was AF recurrence within 24 hours after IV amiodarone discontinuation. Safety outcomes include occurrence of bradycardia or hypotension while on amiodarone. A total of 184 patients were included for analysis. AF recurrence occurred in 24.5% of patients (n = 45). No significant association was found between various overlap durations and AF recurrence (odds ratio (OR) 1.00, 95% CI 1.00-1.01, P = 0.9). In addition, no significant association was found between duration of overlap and rates of bradycardia (OR 1.00, 95% confidence interval (CI) 0.99-1.00, P = 0.08) or hypotension (OR 1.00, 95% CI 0.99-1.00, P = 0.21), which occurred in 35.9% and 47.3% of patients, respectively. Our study suggests following conversion to normal sinus rhythm; cardiothoracic surgery patients can effectively and safely be transitioned from IV to oral amiodarone without the need for specific overlap duration or transition strategy.