Catheter ablation of the atrioventricular conduction system to treat patients with atrial tachyarrhythmias, including patients with pacemakers

ABSTRACT

Electrical catheter ablation of the AV conduction system is a safe and effective procedure for patients with intractable atrial tachyarrhythmias, including patients with previously implanted pacemakers. Seven such patients were treated with this procedure, and there were no complications. All seven patients’ tachycardia was relieved, and six had sustained, chronic, complete AV block at follow-up (mean 7.4 months). Production of chronic, complete AV block appears to require two shocks at initial ablation and a unipolar His-bundle electrogram >0.4 mV. Electrical ablation of the AV conduction system seems to have permanently converted one patient’s chronic atrial fibrillation to sinus rhythm., This procedure caused no adverse sequelae in previously implanted pacemakers or leads. In one patient, the procedure temporarily elevated pacing thresholds in the ventricle and the atruium.