A new radiofrequency thermal balloon catheter for pulmonary vein isolation

OBJECTIVES We sought to evaluate whether porcine pulmonary vein (PV) isolat ion (PVI) can be produced by ablation using our novel radiofrequency (RF) t hermal balloon catheter (RBC). BACKGROUND It has been proposed that PVI can prevent focal atrial fibrillat ion (AF) originating in or close to the PV. METHODS The PBC is composed of a 12F main shaft, a 4F inner tube and a ball oon. Inside the balloon, there is a unipolar coil electrode with a thermoco uple sensor mounted along the tube, the former to deliver RF energy (13.56 MHz) and the latter to monitor the temperature. After the presence of a PV potential was confirmed, the RBC was safely inserted into the left atrium ( LA) by the trans-septal approach. Once the balloon was inflated and optimal ly wedged at the junction between the PV and LA, RF energy was applied for 5 min. Radiofrequency catheter ablation (RFA) was repeated up to three time s, until elimination of the PV potential or dissociation between the LA and PV was observed. Finally, each heart was examined histologically. RESULTS In 18 PVs that had PV potentials, PVI was performed, resulting in s uccess in 15 (success rate 83%, 95% confidence interval [CI] 58.0% to 96.3% ; failure rate 17%, 95% CI 3.7% to 42.0%). After successful PVI, the PV pot entials completely disappeared and the histologic examination revealed circ umferential, transmural necrosis around the PV trunks. No major early compl ications, such as PV stenosis or macroscopic thrombosis, were observed. CONCLUSIONS The RBC was useful for PVI. (J Am Coll Cardiol 2001;38:2079-86) (C) 2001 by the American College of Cardiology.