This is a multi-center, prospective open label, feasibility study evaluating the safety and efficacy of the combined ablation procedure for the treatment of longstanding persistent atrial fibrillation.

The purpose of this feasibility study is to evaluate the safety and efficacy of the epicardial / endocardial combined procedure using the nContact Numeris®-AF Guided Coagulation System with VisiTrax® epicardially and the St. Jude Medical Therapy™ Cool Path™ Ablation Catheter endocardially to treat longstanding persistent Atrial Fibrillation (AF) patients.

Inclusion Criteria:

• Age > 18 years; < 80 years
• Left atrium less than or equal to 6.5 cm (TTE)
• History of AF for less than or equal to 10 years
• Provided written informed consent
• Symptomatic longstanding persistent Atrial Fibrillation (AF).

Exclusion Criteria:

• Patients requiring concomitant surgery
• Left ventricular ejection fraction < 30%
• Pregnant or planning to become pregnant during study
• Co-morbid medical conditions that limit one year life expectancy
• Measured left ventricular wall thickness > 1.5 cm
• History of coagulopathy
• Previous cardiac surgery
• History of pericarditis
• Previous cerebrovascular accident (CVA), excluding fully resolved TIA
• Patients who have active infection or sepsis
• Patients who have uncorrected reversible cause(s) of AF
• Patients who are contraindicated for anticoagulants
• Patients who are being treated for arrhythmias other than AF
• Patients who have had any previous AF or left atrial catheter ablation
• 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).