A prospective, non-randomized, multi-center clinical trial. The patient population includes patients with permanent or persistent AF requiring valve replacements or repairs, ASD repairs, PFO closure or coronary artery bypass grafts (CABG) procedures. Patients are not allowed to have had previous atrial ablation, AV-nodal ablation, or surgical Maze procedure.

The Cardioblate Surgical Ablation System is cleared in Canada and Europe for ablation of cardiac tissue for the treatment of cardiac arrhythmias. In the United States, the Cardioblate bipolar is approved for soft tissue ablation, while the Cardioblate Pen is approved for cardiac tissue ablation. The purpose of the clinical study is to obtain a labeling claim for the US market that the Cardioblate Surgical Ablation System can be used for ablation of cardiac tissue in the treatment of cardiac arrhythmias such as atrial fibrillation among permanent and persistent AF patients.

Inclusion Criteria:

• Patients must meet all of the following criteria to be enrolled in the study:

  1. Documented history of AF a For inclusion in permanent AF arm: Patients must have a documented history of permanent AF (cardioversion failure) as defined by the ACC/AHA/ESC Guidelines; Documentation of AF must include one or more chart references to AF and/or one or more ECG's with AF prior to the patient's surgery. Other supporting information could include references to cardioversion attempts using either drugs or electrical shock. b For inclusion in persistent AF arm: Patients must have a documented history of persistent AF as defined by the ACC/AHA/ESC Guidelines: characterized as episodes of non-self-terminating atrial fibrillation that usually lasts more than 7 days
  2. Concomitant indication (other than AF) for open-heart surgery for one or more of the following:

a Mitral valve repair or replacement, b Aortic valve repair or replacement, c Tricuspid valve repair or replacement, d ASD repair, e PFO closure, or f CABG procedures; 3 Able to take the anticoagulant warfarin or other ACC/AHA/ESC-recommended anticoagulant medication; 4 Greater than or equal to 18 years of age; 5 Able and willing to comply with study requirements by signing a Patient Informed Consent form.

Exclusion Criteria:

• Patients who meet any of the following criteria may not be enrolled in the study:

  1 Wolff-Parkinson-White syndrome, 2 NYHA functional class = IV, 3 Left ventricular ejection fraction ≤ 30%, 4 Left atrial diameter > 7.0 cm, 5. Need for emergent cardiac surgery (i.e. cardiogenic shock) or redo open heart surgery, 6 Preoperative need for an intra-aortic balloon pump or intravenous inotropes, 7 Previous atrial ablation, AV-nodal ablation, or surgical Maze procedure, 8 Contraindication for anticoagulation therapy, 9 Current diagnosis of active systemic infection, 10 Renal failure requiring dialysis or hepatic failure, 11 Documented myocardial infarction 6 weeks prior to study enrollment, 12 Life expectancy of less than one year, or 13 Pregnancy or desire to be pregnant within 12-months of the study treatment.