Pacemaker function during radiofrequency ablation.

There are increasing numbers of radiofrequency current ablation procedures being reported. Selected patients have antitachycardia or antibradycardia pacemakers. The pacemaker behavior during and after ablation procedures differs widely. We report on the pacemaker reaction of 25 patients with 13 different devices, most with unipolar electrodes. Sensing failures were observed in 8 (32.0%) and pacing failures in 4 (16.0%) patients. Prolonged pauses and induction of tachyarrhythmias were observed. No pacemaker damage was seen although it is reported by other investigators. We recommend deactivation of implanted generators and an external bipolar pacing electrode. Manufacturers should focus their attention on this problem and protect the generators and their functions for 500 kHz radiofrequency current.