[Comparison of the efficacy and safety of dronedarone and flecainide as maintenance antiarrhythmic therapy for sinus rhythm in atrial fibrillation].

Introduction And Objectives: Dronedarone and flecainide are the first pharmacological choice to reduce recurrence of atrial fibrillation (AF); however, there are no studies comparing them. A study was performed to compare the efficacy in terms of recurrence of AF and safety of both drugs.

Methods: A retrospective cohort study was conducted that included 123 consecutive patients treated with flecainide or dronedarone due to paroxysmal AF (76.4%) or persistent AF (23.6%), from October 2010 to February 2013. Electrical cardioversion was performed in 7.3% of patients and pharmacological cardioversion in 16.3%. The median (interquartile range) follow-up was 301days (92-474) with a mean of 2.8 reviews per patient. Time to first event analysis was performed using Kaplan-Meier and Cox regression, adjusted for propensity score.

Results: Of the 123 consecutive patients with AF included, 71 were on dronedarone and 52 on flecainide. During the follow-up, there were 36 AF recurrences and 20 safety events. There were recurrences in 36.6% of patients treated with flecainide, compared with 21% of those receiving dronedarone (P=.073). Dronedarone showed to be at least as effective as flecainide in preventing recurrence of atrial fibrillation (HR: 0.53, 95% CI: 0.20-1.44, P=.221), and demonstrated an acceptable safety profile when compared with flecainide (HR: 0.68, 95% CI: 0.18-2.53, P=.566).

Conclusions: In our experience, dronedarone has been at least as effective and safe as flecainide, despite it was most frequently prescribed in patients with worse baseline risk profile.