Long-term efficacy and safety of propafenone and sotalol for the maintenance of sinus rhythm after conversion of recurrent symptomatic atrial fibrillation

This study was performed to evaluate, using a randomized double-blind, plac ebo-controlled protocol, the longterm efficacy and safety of propafenone an d sotalol in maintaining sinus rhythm after conversion of recurrent symptom atic atrial fibrillation (AF). The maintenance of sinus rhythm in patients with recurrent AF has several potential benefits, the most important being a reduced risk of thromboembolic events. Three hundred patients with recurr ent AF (greater than or equal to4 episodes in the last year) and AF at enro llment lasting <48 hours were randomized to receive either propafenone (mea n daily dose 13 +/- 1.5 mg/kg; 102 patients), sotalol (mean daily dose 3 +/ - 0.4 mg/kg; 106 patients), or placebo (92 patients). After 1-year follow-u p, Kaplan-Meier estimates of the proportion of patients remaining in sinus rhythm were comparable between propafenone (63%) and sotalol (73%) and supe rior to placebo (35%; p = 0.001 vs both drugs). Symptomatic recurrences occ urred later with propafenone and sotalol than with placebo. Nine patients ( 9%) in the propafenone group, 11 (10%) in the sotalol group, and 3 (3%) in the placebo group discontinued therapy due to adverse effects. Malignant no nfatal arrhythmias due to proarrhythmic effects were documented with sotalo l only, and occurred <72 hours from the beginning of therapy in 4 patients (4%). During recurrences, the ventricular rate was significantly reduced in patients taking propafenone and sotalol (p = 0.001 for both drugs vs place bo). The likelihood of remaining in sinus rhythm during follow-up was highe r in younger patients with smaller left atria[ size and without concomitant heart disease. In patients with recurrent symptomatic AF, propafenone and sotalol are not significantly different from each other and are superior to placebo in maintaining sinus rhythm at 1 year. Recurrences occur later and tend to be less symptomatic with propafenone and sotalol compared with pla cebo. (C) 2001 by Excerpta Medica, Inc.