OBJECTIVE Whether early rhythm suppression with extensive antiarrhythmic drugs (AADs) in persistent atrial fibrillation (AF) after catheter ablation decreases arrhythmia recurrence is unknown. We now report the 12-month follow-up data in this prospective and randomized study. METHODS AND RESULTS 123 consecutive patients with persistent AF undergoing catheter ablation were randomly divided into an extensive AADs therapy group (group 1:62 patients using both class Ic and III AADs) or one AAD therapy group (group 2:61 patients using class Ic or III AADs alone) for the initial 2 months after ablation. Recurrence of atrial tachyarrhythmias (ATa) was valuated at both 2 months and 12 months following ablation. During the first 2 months after ablation, less ATa were found in group 1 compared with group 2 (17/62 versus 29/61, P = 0.021). However, there was no difference with regard to ATa at 12 months between the groups (21/62 versus 22/61, P = 0.799). ATa at 2 months and left atrial diameter (LAD) were the statistically significant predictors of ATa during 12-month follow-up. CONCLUSIONS While use of extensive AADs within the initial 2 months after persistent AF ablation decreases early ATa, it does not prevent late ATa. Moreover, LAD as well as early ATa is a strong predictor of ATa at 12 months.