Circumferential pulmonary-vein ablation for chronic atrial fibrillation

Background: We conducted a randomized, controlled trial of circumferential pulmonary-vein ablation for the treatment of chronic atrial fibrillation. Methods: A total of 146 patients with a mean (+/-SD) age of 57+/-9 years who had chronic atrial fibrillation were randomly assigned to receive amiodarone and undergo two cardioversions during the first three months alone (the control group) or in combination with circumferential pulmonary-vein ablation. Cardiac rhythm was assessed with daily telephonic transmissions for one year. The left atrial diameter and the severity of symptoms were assessed at 12 months. Results: Among the 77 patients assigned to undergo circumferential pulmonary-vein ablation, ablation was repeated because of recurrent atrial fibrillation in 26 percent of patients and atypical atrial flutter in 6 percent. An intention-to-treat analysis showed that 74 percent of patients in the ablation group and 58 percent of those in the control group were free of recurrent atrial fibrillation or flutter without antiarrhythmic-drug therapy at one year (P=0.05). Among the 69 patients in the control group, 53 (77 percent) crossed over to undergo circumferential pulmonary-vein ablation for recurrent atrial fibrillation by one year and only 3 (4 percent) were in sinus rhythm without antiarrhythmic-drug therapy or ablation. There were significant decreases in the left atrial diameter (12+/-11 percent, P<0.001) and the symptom severity score (59+/-21 percent, P<0.001) among patients who remained in sinus rhythm after circumferential pulmonary-vein ablation. Except for atypical atrial flutter, there were no complications attributable to circumferential pulmonary-vein ablation. Conclusions: Sinus rhythm can be maintained long term in the majority of patients with chronic atrial fibrillation by means of circumferential pulmonary-vein ablation independently of the effects of antiarrhythmic-drug therapy, cardioversion, or both. The maintenance of sinus rhythm is associated with a significant decrease in both the severity of symptoms and the left atrial diameter.