Objective: The purpose of the present study was to assess the efficacy of the long-term results after video-assisted pulmonary vein isolation and left atrial appendage excision for lone atrial fibrillation (AF) and to determine the most significant risk factors for the long-term results. Methods: From December 2006 to December 2012, 332 consecutive patients with lone AF underwent minimally invasive surgical ablation at our center. Of the 332 patients, 91, who had undergone video-assisted pulmonary vein isolation >5 years earlier, were evaluated in the present study (48 with paroxysmal AF, 21 with persistent AF, and 22 with long-standing persistent AF). The median follow-up period was 66 months. The primary endpoint was the success rate of video-assisted pulmonary vein isolation, defined as the absence of any atrial arrhythmia recurrence lasting >30 seconds at the clinical visit and on the electrocardiogram or long-term cardiac rhythm recording after discharge. Results: During the follow-up period, 1 patient (1.1%) experienced a stroke and 4 (4.4%) died of noncardiac disease. At the 5-year follow-up point, 43 of 78 patients (55.1%) were in normal sinus rhythm. Of the 39 patients with paroxysmal AF and 39 with nonparoxysmal AF, 27 (69.2%) and 16 (44.1%) were in normal sinus rhythm, respectively. The results of the univariate and multivariate analyses of the preoperative risk factors for AF recurrence showed a left atrial diameter of >= 44 mm (hazard ratio, 5.56; 95% confidence interval, 1.68-18.387; P = .005) and an AF duration of >= 31.5 months (hazard ratio, 3.67; 95% confidence interval, 1.50-8.95; P = .004) were the most significant independent risk factors. Conclusions: Patients with lone AF with a large preoperative left atrial diameter and long AF duration will not be suitable for video-assisted pulmonary vein isolation alone and might need to undergo ablation of the lesions.