Proarrhythmic Adverse Events Analysis of FDA Reported Dofetilide and Sotalol Use

Abstract 2278839, presented at Western Atrial Fibrillation Symposium 2026

Antiarrhythmic drugs (AAD) sotalol and dofetilide are commonly used to treat atrial fibrillation (AF). Both medications may cause arrhythmogenic adverse events (AEs), although incredibly rare (< 0.6%), including ventricular arrhythmias. We performed a pharmacovigilance and disproportionality study to compare proarrhythmic AEs of dofetilide and sotalol. To evaluate the difference between AEs in AF patients prescribed sotalol versus dofetilide to lend additional insight to the risks of the two commonly prescribed AADs.The FDA Adverse Event Reporting System (FAERS) database was searched for AF patients prescribed sotalol or dofetilide. Proarrhythmic AEs, including ventricular tachycardia (VT), TdP, cardiac arrest, and bradycardia events were identified for the target population. Additionally, recurrent AF episodes were noted. The reporting odds ratios (RORs) were calculated between sotalol and dofetilide for each proarrhythmic event (VT, TdP, cardiac arrest, bradycardia) and AF recurrence (Table I).From 2004-2023, 3,097 cardiac AEs were reported for sotalol and dofetilide. Recurrent AF was recorded in 436 cases (222 dofetilide, 214 sotalol) and dofetilide displayed a greater ROR for AF recurrence [27 (95% CI: 25-29), sotalol: [17 (16-19)]. Sotalol demonstrated greater ROR values for TdP [76 (66-87) vs. 53 (44-63)] and bradycardia [15 (13, 17) vs. 2 (2, 3)].Cardiac AEs and AF recurrence are commonly reported to the FDA in patients taking sotalol and dofetilide. While TdP was found to be more common in patients prescribed sotalol, AF recurrence was most commonly reported with dofetilide use. These factors may influence decision-making when selecting AADs for AF patients. These findings underscore the need for careful patient selection, close monitoring, and individualized risk assessment. Further research is required to determine the clinical implications of AADs and AEs.