Primary Outcome Measures:
- sinus rhythm at end of follow-up (6 months) [ Time Frame: 6 months ] [ Designated as safety issue: No ]
Secondary Outcome Measures:
- absence of permanent atrial fibrillation at end of follow-up [ Time Frame: 6 months ] [ Designated as safety issue: No ]
- absence of any symptomatic atrial fibrillation [ Time Frame: 6 months ] [ Designated as safety issue: No ]
- atrial volume and contraction at end of follow-up [ Time Frame: 6 months ] [ Designated as safety issue: No ]
- left ventricular diameters and function at end of follow-up [ Time Frame: 6 months ] [ Designated as safety issue: No ]
- thromboembolism [ Time Frame: 6 months ] [ Designated as safety issue: Yes ]
- pulmonary vein stenosis [ Time Frame: 6 months ] [ Designated as safety issue: Yes ]
- immediate postoperative complications (and related sequelae) [ Time Frame: directly post-operative ] [ Designated as safety issue: Yes ]
- surgical procedure time and total epicardial ablation time [ Time Frame: directly post-operative ] [ Designated as safety issue: No ]
- any pacemaker implantation [ Time Frame: 6 months ] [ Designated as safety issue: Yes ]
- mortality [ Time Frame: 6 months ] [ Designated as safety issue: Yes ]
- bleeding [ Time Frame: 6 months ] [ Designated as safety issue: Yes ]
- hospitalization for heart failure [ Time Frame: 6 months ] [ Designated as safety issue: No ]
- antiarrhythmic drugs during follow-up [ Time Frame: 6 months ] [ Designated as safety issue: No ]
- electrical cardioversions during follow-up [ Time Frame: 6 months ] [ Designated as safety issue: No ]
- re-ablations [ Time Frame: 6 months ] [ Designated as safety issue: No ]
- syncope [ Time Frame: 6 months ] [ Designated as safety issue: No ]
- quality of life and specific arrhythmia symptoms [ Time Frame: 6 months ] [ Designated as safety issue: No ]
Atrial fibrillation is a major health problem.Despite adequate treatment of underlying heart disease, rhythm control is unsuccessful in almost half of patients, also in patients with lone atrial fibrillation.If patients remain highly symptomatic, a non-pharmacological approach may be considered including pulmonary vein isolation and Cox maze III surgery. Maze III surgery has high succes rates, however it includes major cardiac surgery with substantial risk of complications. New surgical strategies for symptomatic lone atrial fibrillation focus on minimal invasive off-pump procedures omitting cardiopulmonary bypass (and thus lowering the complication rate), while taking advantage of an easier approach to the ablation site and a shorter procedure time. Epicardial surgical ablation isolating pulmonary veins by high intensity focused ultrasound performed off-pump by Video Assisted Thoracic Surgery (VATS)may be a promising treatment option. In this pilot study, we aim to study the feasibility of this new surgical ablation approach in patients with lone atrial fibrillation.