Patients did not want to be randomized in hybrid ablation.

The overall objective of the study is to compare and assess the clinical outcomes of the standard of care hybrid ablation using epicardial ablation in conjunction with endocardial PVI alone versus epicardial ablation in conjunction with endocardial ablation using PVI with additional RF ablation in a randomized, prospective population of patients with persistent AF of at least 6 months duration. All devices that are used are being utilized under the approved labeling of the devices.

Atrial fibrillation (AF) is one of the leading causes of stroke and heart failure. It is also a major cause of hospitalizations and mortality (Stewart, Wattigney, and Wolf). Patients with atrial fibrillation (AF) who are intolerant to Class I and III antiarrhythmic drugs often require endocardial ablation, which can include pulmonary vein isolation (PVI) using radiofrequency (RF) catheter ablation or cryoballoon ablation (Medtronic, MN) and reported success rates vary (Calkins et al). In patients with persistent and long standing persistent AF success rates may not be as high (Akoum et al) and there is little data analyzing outcomes for patients in this population (Calkins et al). Using an epicardial-endocardial, or hybrid, approach Gehi et al describes a 66% 12 month arrythmia-free survival rate following the procedure, with 37% patients still on antiarrythmic drug therapy at 12 months. Furthermore, a paper by Anderson et al reports that the hybrid ablation results in lower costs and higher quality adjusted life years for patients with non-paroxysmal AF as reported by the studie's results of fewer repeat ablations and maintenance of sinus rhythm at 5 years. Conflicting reports exist on how much endocardial catheter ablation is needed for patients in persistent and long standing persistent AF. Verma et al reports results for patients in persistent AF having endocardial PVI compared to P VI plus additional linear lesions. Eighteen month success rates for these patients were 59% and 46% respectively.

Success of surgical hybrid ablation using epicardial ablation cocontaminent with endocardial PVI alone versus the hybrid approach using epicardial ablation with endocardial ablation consisting of PVI ablation and RF ablation has not been studied using a randomized, prospective approach.

If it is found that the PVI alone is as effective as PVI plus additional catheter ablation for patients receiving a hybrid ablation, it may reduce the need for extensive catheter ablation, thereby reducing the radiation exposure, procedure time, and radiofrequency ablation time.

Inclusion Criteria:

• The subject is 18 years of age or older
• Left atrium < 6.0 em (Trans Thoracic Echo - TTE- parasternal4 chamber view performed within 6 months)
• History of AF for at least 6 months
• Failed or refractory to one AAD (class I and/or Ill)
• Documentation of persistent AF
• Provided written informed consent
• Be eligible for the hybrid procedure

Exclusion Criteria:

• Pregnant or planning to become pregnant during study
• Co-morbid medical conditions that limit one year life expectancy
• Previous cardiac surgery
• Previous abdominal surgery which will prevent epicardial access
• History of pericarditis
• Previous cerebrovascular accident (CVA), excluding fully resolved TIA
• Patients who have active infection or sepsis
• Patients with esophageal ulcers strictures and varices
• Patients with renal dysfunction who are not on dialysis (defined as GFR ::5 40)
• Patients who are contraindicated for anticoagulants such as heparin and coumadin
• Patients who are being treated for ventricular arrhythmias
• Patients who have had a previous left atrial catheter ablation for AF (does not include ablation for AFL or other supraventricular arrhythmias)
• Current participation in another clinical investigation of a medical device or a drug, or recent participation in such a study within 30 days prior to study enrollment
• Not competent to legally represent him or herself (e.g., requires a guardian or caretaker as a legal representative)