Paroxysmal atrial flutter and fibrillation associated with preexcitation syndrome: treatment with ajmaline

Ajmaline was administered intravenously to six patients with the Wolff-Parkinson-White syndrome for the acute management of paroxysmal atrial flutter (three patients) or fibrillation (three patients) with a fast ventricular response (over the accessory pathway). Ajmaline increased refractoriness in the accessory pathway in all three patients with atrial flutter and stopped the flutter in one. The drug completely abolished preexcitation in two of the three patients with atrial fibrillation, decreasing the means ventricular rate of 240 and 300 beats/min to 110 and 180 beats/min, respectively. In the third patient with atrial fibrillation, ajmaline increased refractoriness over the accessory pathway, decreasing the mean ventricular rate of 300 beats/min to 160 beats/min. In two patients ajmaline was continued as an intravenous maintenance infusion until sinus rhythm was restored. It is concluded that ajmaline is an effective drug for the acute management of atrial flutter or fibrillation with a fast ventricular response in patients with the Wolff-Parkinson-White syndrome.