A randomized, double-blind, placebo-controlled evaluation of the efficacy and safety of intravenously administered dofetilide in patients with Wolff-Parkinson-White syndrome

\Pharmacological conversion of arrhythmias in Wolff-Parkinson-White (WPW) s yndrome is often frequently undertaken. Current antiarrhythmic drugs used f or conversion can be associated with significant side effects and variable efficacy. Fifteen male patients (mean age 34, range 18-63 years) with WPW s yndrome and atrial fibrillation or AVRT induced in the electrophysiology la boratory were enrolled in a prospective, randomized, placebo-con trolled cr ossover study. Patients were randomized to one of two doses of intravenous dofetilide or placebo. Patients who failed to respond to this initial infus ion received a second higher dose infusion of dofetilide. With the initial infusion, six of ten dofetilide patients converted to sinus rhythm compared to one of five placebo patients. After a second infusion of dofetilide for placebo patients and higher dose dofetilide for low dose dofetilide patien ts, the overall conversion rate was 71% with dofetilide compared with 20% f or placebo (P = 0.046). Atrial fibrillation converted to sinus rhythm in 82 % of patients who received dofetilide. Intravenous dofetilide was safe and effective at converting induced atrial fibrillation in patients with WPW sy ndrome.