UPPER RATE PACING AFTER RADIOFREQUENCY CATHETER ABLATION IN A MINUTE VENTILATION RATE-ADAPTIVE DDD PACEMAKER

A 58-year-old man with an implanted minute ventilation rate adaptive D DD pacemaker underwent RF ablation of the AV junction because of sympt omatic supraventricular tachyarrhythmias. Immediately after ablation, while the pacemaker was programmed in the DDDR mode, AV sequential pac ing at upper rate was observed. After programming the pacing system to the DDD mode and repeated ablation, no abnormalities were observed. I t was concluded that AV sequential upper rate pacing was caused by fal se interpretation of the RF current by the sensor measuring transthora cic impedance as an indicator for minute ventilation.