[Effectiveness and electrophysiologic action of amiodarone in controlling attacks of supraventricular paroxysmal tachycardia].

The study was undertaken to examine 21 patients with episodes of recurrent ventricular paroxysmal tachycardia. The latter were arrested by amiodarone intravenously injected in a dose of 5 mg/kg. The episode was stopped in 9 (45%) cases, i.e. in 6 (60%) cases with atrioventricular junction tachycardia and 3 (30%), involving accessory conduction tracts. Amiodarone-induced deterioration was observed in the atrioventricular conduction (in the anterograde one in most cases) and that along the accessory conduction tracts. In all the cases, the episode was abolished due to the anterograde block of impulse conduction along the atrioventricular node. There was an amiodarone-induced small decrease in the function of automatism in the sinus node.