Guidant Microwave Ablation System for the Treatment of Atrial Fibrillation

Inclusion Criteria: Patient age >= 18 years Documented permanent AF (for at least three months) Scheduled for an open chest cardiac surgery for the primary indication of mitral valve repair or replacement Has been informed of the nature of the study, agrees to its provisions, and provided written informed consent, which was approved by the appropriate Institutional Review Board/Ethics Committee of the respective clinical site Exclusion Criteria: Cerebral vascular accident (CVA, stroke) or transient ischemic attack (TIA) within the previous 6 months Myocardial infarction within the previous 6 weeks Documented history of pulmonary vein stenosis Previous ablation attempt for AF Previous thoracic procedures Left atrial size > 7.0 cm Left ventricular ejection fraction < 30% Presence of left atrial or left atrial appendage thrombi Esophageal fistula or other stricture, untreated esophagitis, varices, dysphagia or odynophagia contraindicating transesophageal echocardiography Known allergy or contraindication to warfarin therapy Known allergy or contraindication to antiarrhythmic (Classes IA, IC, III) therapy Other comorbidity with reduced life expectancy of less than 1 year or protocol noncompliance that would limit follow-up Geographically remote or unable to return for follow-up examinations Pregnant or planning to become pregnant during the study Enrolled in any concurrent study, without Guidant written approval, that may confound the results of the study