Circumferential radiofrequency ablation of pulmonary vein ostia - A new anatomic approach for curing atrial fibrillation

Background-The pulmonary veins (PVs) and surrounding ostial areas frequentl y house focal triggers or reentrant circuits critical to the genesis of atr ial fibrillation (AF). We developed an anatomic approach aimed at isolating each PV from the left atrium (LA) by circumferential radiofrequency (RF) l esions around their ostia. Methods and Results-We selected 26 patients with resistant AF, either parox ysmal (n=14) or permanent (n=12). A nonfluoroscopic mapping system was used to generate 3D electroanatomic LA maps and deliver RF energy. Two maps wer e acquired during coronary sinus and right atrial pacing to validate the la teral and septal PV lesions, respectively. Patients were followed up closel y for greater than or equal to6 months. Procedures lasted 290+/-58 minutes, including 80+/-22 minutes for acquisition of all maps, and 118+/-16 RF pul ses were deployed. Among 14 patients in AF at the beginning of the procedur e, 64% had sinus rhythm restoration during ablation. PV isolation was demon strated in 76% of 104 PVs treated by low peak-to-peak electrogram amplitude (0.08+/-0.02 mV) inside the circular line and by disparity in activation t imes (58+/-11 ms) across the lesion. After 9+/-3 months, 22 patients (85%) were AF-free, including 62% not taking and 23% taking antiarrhythmic drugs, with no difference (P=NS) between paroxysmal and permanent AF. No thromboe mbolic events or PV stenoses were observed by transesophageal echocardiogra phy. Conclusions-Radiofrequency PV isolation with electroanatomic guidance is sa fe and effective in either paroxysmal or permanent AF.