Electrocardiogram of the month Tachycardia caused by a double fire – simultaneous double atrioventricular nodal conduction: a rare or underdiagnosed arrhythmia? Spectrum of electrocardiographic pictures in three patients

Abstract

We describe three patients with incessant supraventricular arrhythmia known as nonreentrant supraventricular tachycardia that is caused by double atrioventricular nodal conduction of each sinus beat. Electrocardiograms showing various patterns of atrioventricular conduction are presented. These include Wenckebach periodicity with AV block in both AV nodal pathways, only in slow pathway, only in fast pathway or picture mimicking a regular supraventricular tachycardia with T wave pseudo-alternans. We propose a new name for this arrhythmia: AV nodal dual response bigeminy. All three cases were successfully treated with radiofrequency ablation: two of slow pathway and one of AV node.