Circumferential radiofrequency ablation of pulmonary vein ostia for atrial fibrillation: Long-term results from a large, single-Center experience

The dominance of the left atrium (LA) in the pulmonary vein (PV) regions for triggering and maintaining atrial fibrillation (AF) is now widely recognized. Radiofrequency (RF) PV isolation with electroanatomical guidance has recently emerged as a promising approach for AF treatment. We report the clinical outcome of the procedure in 251 consecutive patients with paroxysmal (n=179) or permanent (n=72) AF. Circular RF lesions were deployed transseptally during sinus rhythm or AF at 5 mm from PV ostia. Procedural and mapping times were 112±32 min and 75±27 min, respectively, with 29±11 min of fluoroscopy. Complete lesions (peak-to-peak bipolar electrogram amplitude <0.1 mV inside the line and no double potentials) were achieved in 85% of the veins treated. Sinus rhythm was restored during RF delivery in 52% and by DC shock in the remaining. Major complications (cardiac tamponade) occurred in 3%. Extent of ablated area was 4.9±0.5 cm2, accounting for 28±9% of the total LA map surface. After 11±5 months, procedure success rates (freedom from AF without antiarrhythmic drugs) were 85% for paroxysmal and 68% for permanent AF. No PV stenoses were detected. By univariate analysis, an increased risk of recurrence was predicted by LA dilation (diameter >50 mm), AF duration, and a low ablated area (<15% of total LA surface). After adjustment, only the latter variable continued to be significant (odds ratio 3.5, 95% confidence interval, 1.6-5.8). In conclusion, RF PV isolation is safe and effective in either paroxysmal or permanent AF. Patients with enlarged left atrium may require wider lesions to achieve AF suppression.