Short-term versus long-term antiarrhythmic drug treatment after cardioversion of atrial fibrillation (Flec-SL): a prospective, randomised, open-label, blinded endpoint assessment trial

Antiarrhythmic drugs prolong the atrial action potential and refractory period, and thereby prevent recurrent atrial fibrillation after cardioversion. The atrial action potential normalises after 2—4 weeks of sinus rhythm, suggesting that antiarrhythmic drugs might not be needed beyond that period. Therefore, we investigated whether short-term antiarrhythmic drug treatment after cardioversion is non-inferior to long-term treatment.

We enrolled patients in a prospective, randomised, open-label, blinded endpoint assessment trial between May 4, 2007, and March 12, 2010, at 44 centres in Germany. Eligible patients were adults with persistent atrial fibrillation undergoing planned cardioversion. After successful cardioversion, patients were randomly assigned in permuted blocks of six per centre to: no antiarrhythmic drug treatment (control); treatment with flecainide (200—300 mg per day) for 4 weeks (short-term treatment); or flecainide for 6 months (long-term treatment). The primary endpoint was time to persistent atrial fibrillation or death. Patients and clinicians were unmasked to group assignment and treatment.  Read more