Use of flecainide acetate for refractory junctional tachycardias in children with the Wolff-Parkinson-White syndrome.

The response of sustained supraventricular tachycardia to intravenous and oral flecainide acetate was investigated in 5 children, aged 5.5 to 11.5 years, who had tachycardias associated with Wolff-Parkinson-White syndrome. All children had failed to respond to at least 2 conventional agents. The effect of flecainide was studied using intracardiac techniques. Intravenous flecainide terminated tachycardia in all 5 patients. After drug infusion, slow, sustained tachycardia could be initiated in 1 patient. With oral treatment, slow, sustained tachycardia was started in 2 children and nonsustained in 2. One child had no inducible tachycardias. In 4 of 5 patients, long-term treatment has reduced the frequency of episodes and the drug is well tolerated. Thus, flecainide may be used to terminate and suppress junctional tachycardias in children who have failed to respond to conventional therapy.