Combined sotalol and flecainide given at low dosage in patients with the Wolff-Parkinson-White syndrome.

We determined the effects of combined sotalol (160 mg/day) and flecainide (200 mg/day) in 15 patients with the Wolff-Parkinson-White syndrome. After medication given for 3 days, the plasma levels were 0.8 +/- 0.3 micrograms/ml for sotalol and 232 +/- 104 ng/ml for flecainide. Electrophysiologic testing showed complete blockade of the accessory pathway in 4 patients and a decrease in the anterograde conduction capacity by 27% in the remainder. The effect on the accessory pathway was unrelated to the resting conduction properties. Initiation of circus movement tachycardia was prevented in 5 of 11 patients. During a median period of 28 months of follow-up, 87% of patients were either free of tachycardia or satisfactorily improved. No proarrhythmic or adverse drug effects were observed.