A randomized study on the efficacy of intravenous cibenzoline and pilsicainide administered prior to electrical cardioversion in patients with lone paroxysmal and persistent atrial fibrillation.

Methods And Results: This study included 68 patients (47 men, 21 women, mean age 69 years) in whom atrial fibrillation (AF) recurred immediately after electrical cardioversion (EC) was performed with no antiarrhythmic drugs. After administration of cibenzoline (Cib, 70 mg) or pilsicainide (Pil, 50 mg) on a randomized basis, all patients again underwent EC at the same energy as that prior to administration of antiarrhythmic drugs. We compared the efficacy of Cib (n = 35) and Pil (n = 33), and examined factors affecting successful cardioversion in patients treated with Cib.