Radiofrequency catheter ablation for incessant atrioventricular nodal reentrant tachycardia normalized H-V block associated with tachycardia-induced cardiomyopathy.

A 30-year-old man was admitted for treatment of tachycardia-induced cardiomyopathy caused by incessant atrioventricular nodal reentrant tachycardia (AVNRT). An echocardiogram revealed dilatation of all cardiac chambers with severe globally depressed biventricular systolic function. During an electrophysiologic study, HV interval was prolonged to 118 ms by atrial extrastimulus and 2:1 HV block was documented during AVNRT. Four weeks after catheter ablation for AVNRT, an echocardiogram demonstrated regression of the wall motion abnormality of both ventricles and of their dimensions. In the electrophysiologic study, the HV conduction disturbance disappeared. So far, this is the first case in which tachycardia-induced cardiomyopathy was accompanied by transient His-Purkinje conduction abnormality.