Long-term results of ablation for isolated atrial fibrillation through a right minithoracotomy: toward a rational revision of treatment protocols

Objective: Despite continued technical improvements, results of transcatheter radiofrequency ablation of atrial fibrillation may be suboptimal in some patient subgroups. Short-term follow-up of minimally invasive epicardial ablation of isolated atrial fibrillation has been encouraging.

Methods: One hundred four patients with drug-refractory isolated atrial fibrillation underwent minimally invasive surgical ablation through right 3- to 4-cm minithoracotomy by isolation of pulmonary veins and were followed-up for an average of 17 months. Previous failed transcatheter ablation was not a criterion for this procedure. Antiarrhythmic drugs were continued until postoperative month 6, despite demonstration of stable sinus rhythm.

Results: The procedure was confirmed to be safe (1 case of procedure-related morbidity, no operative deaths) and effective (89% overall freedom from recurrent arrhythmia at follow-up, 96% freedom from paroxysmal atrial fibrillation, 80% freedom from persisting type atrial fibrillation). Results tended to improve with the expansion of the surgical experience. Cox hazard regression and Kaplan-Meier analysis identified persisting type atrial fibrillation and enlarged left atrium as the major predictors of recurrent atrial fibrillation at follow-up. Health-related quality of life was confirmed to be improved at the end of the follow-up relative to baseline in most Medical Outcomes Study 36-Item Short-Form Health Survey domains.

Conclusions: Minimally invasive epicardial ablation of isolated atrial fibrillation yields stable, gradually improving results. Earlier surgical referral is justifiable after careful cardiologic work-up. To define the relative roles of minimally invasive ablation and transcatheter ablation, which may be considered in the future as alternative therapies, a randomized trial to compare these procedures is advisable.