Antiarrhythmics After Ablation of Atrial Fibrillation (5A Study).

BACKGROUND: Atrial arrhythmias are common early after atrial fibrillation (AF) ablation. We hypothesized that empirical antiarrhythmic drug (AAD) therapy for 6 weeks after AF ablation would reduce the occurrence of atrial arrhythmias.

METHODS AND RESULTS: We randomized consecutive patients with paroxysmal AF undergoing ablation to empirical antiarrhythmic therapy (AAD group) or no antiarrhythmic therapy (no-AAD group) for the first 6 weeks after ablation. In the no-AAD group, only atrioventricular nodal blocking agents were prescribed. All patients wore a transtelephonic monitor for 4 weeks after discharge and were reevaluated at 6 weeks. The primary end point of the study was a composite of (1) atrial arrhythmias lasting more than 24 hours; (2) atrial arrhythmias associated with severe symptoms requiring hospital admission, cardioversion, or initiation/change of antiarrhythmic drug therapy; and (3) intolerance to antiarrhythmic agent requiring drug cessation. Of 110 enrolled patients (age 55+/-9 years, 71% male), 53 were randomized to AAD and 57 to no-AAD. There was no difference in baseline characteristics between groups. During the 6 weeks after ablation, fewer patients reached the primary end point in the AAD compared with the no-AAD group (19% versus 42%; P=0.005). There remained fewer events in the AAD group (13% versus 28%; P=0.05) when only end points of AF >24 hours, arrhythmia-related hospitalization, or electrical cardioversion were compared.

CONCLUSIONS: AAD treatment during the first 6 weeks after AF ablation is well tolerated and reduces the incidence of clinically significant atrial arrhythmias and need for cardioversion/hospitalization for arrhythmia management.