Specific Aims: The primary objective of this registry is to determine the percentage of patients who are free from atrial fibrillation (AF) at 6 and 12 months following a surgical ablation procedure when the patient has a history of failing one or more previous catheter based ablations for AF. The first 3 months following surgical ablation will be a blanking period; any arrhythmia occurring during this time will not be used to determine success.

Primary Objectives:

1. Determine the percent success of surgical ablation for AF at 6, and 12 months both on and off of antiarrhythmic drugs (AAD) following a failed catheter based ablation for AF
2. Record and evaluate all complications associated with the surgical procedure.

Secondary Objectives:

1. Evaluate usage of anticoagulants at 6, and 12 months.
2. Determine the percentage of Pulmonary Veins (PV) that were electrically isolated by intra-operative, pre-surgical mapping

Inclusion Criteria:

• Diagnosis of atrial fibrillation
• Has undergone one or more catheter based ablation procedures for AF and the procedure failed
• Has undergone a minimal access surgical ablation procedure for the treatment of AF following failure of catheter based ablation for AF

Patients that have undergone surgical ablation after failing catheter based ablation at investigator sites