Predictors and Outcomes of Pharmacological and Electrical Cardioversion for Atrial Fibrillation and Flutter in an Indian Emergency Department: A Retrospective Study

ABSTRACT Background Cardioversion is widely used to restore sinus rhythm in atrial fibrillation (AF) and atrial flutter (AFL), yet real‐world outcomes and predictors of success remain underexplored in populations with high rheumatic disease burden. The aim was to evaluate the success rate, in‐hospital complications, and predictors of cardioversion among patients presenting with AF or AFL in the emergency department. Methods We retrospectively analyzed 324 patients who underwent cardioversion between December 2021 and March 2025. Demographic, clinical, and echocardiographic data were extracted. Outcomes assessed included cardioversion success and in‐hospital complications. Logistic regression identified independent predictors of success. Results Of 324 patients (median age 57 years; 61.4% male), 80.9% had AF and 19.1% had AFL; 57.1% had persistent arrhythmia and 31.5% had rheumatic heart disease. Overall, 68.2% achieved successful cardioversion. Success differed by strategy: electrical cardioversion (ECV) 94.3%, pharmacological cardioversion (PCV) 40.9%, and mixed 74.3%. Complications occurred in 4.9%, and in‐hospital death occurred in 0.6%. In multivariable analysis, PCV (aOR 9.84; p < 0.001), mixed cardioversion (aOR 4.38; p = 0.006), and pre‐procedural class IV anti‐arrhythmic drug use (aOR 4.67; p = 0.043) were associated with higher odds of failure, whereas mineralocorticoid receptor antagonist use (aOR 0.50; p = 0.037) and electrophysiologist involvement (aOR 0.43; p = 0.037) were associated with lower odds of failure. Conclusion In a real world with a high rheumatic disease burden, cardioversion achieved a two‐thirds success rate with a modest complication rate. ECV was most effective, and specific clinical predictors, including cardioversion strategy, medication use, and electrophysiologist involvement, were associated with outcomes. These findings provide actionable insights for optimizing acute rhythm‐control strategies.