Patients were treated with video-assisted thoracoscopy under general anesthesia, according to a previously described protocol. In brief, PVI was performed from the epicardial side with a bipolar radiofrequency ablation clamp. At least 2 overlapping applications around each of the ipsilateral veins were made, and isolation was confirmed by the absence of PV potentials and exit block during pacing. In addition to PVI, the bilateral epicardial ganglia were found by high-frequency stimulation and ablated, as confirmed by the absence of a vagal response after ablation. Finally additional lines were made to create a posterior box lesion. Sensing and pacing maneuvers verified isolation of the posterior box.

Patients were treated with video-assisted thoracoscopy under general anesthesia, according to a previously described protocol. In brief, PVI was performed from the epicardial side with a bipolar radiofrequency ablation clamp. At least 2 overlapping applications around each of the ipsilateral veins were made, and isolation was confirmed by the absence of PV potentials and exit block during pacing. In addition to PVI, the bilateral epicardial ganglia were found by high-frequency stimulation and ablated, as confirmed by the absence of a vagal response after ablation. Finally additional lines were made to create a posterior box lesion. Sensing and pacing maneuvers verified isolation of the posterior box.The left atrial appendage was removed by stapling and then cutting.