Catheter Ablation vs. Medical Therapy in Congested Hearts With AF

Inclusion Criteria: * must be 18 years of age or older * Provide signed written Informed Consent * symptomatic AF documented by EKG or heart rhythm monitoring within 12 months * patients should be on optimal medical therapy for heart failure for 3 months prior to randomization. Adjustments to medications within this 3 month period are permitted. * chronically impaired LV function defined as EF between 20%-45% within last 3 months * all patients should be on an optimal therapy for impaired LV function * ability to complete 6 minute walk test * eligible for catheter ablation and anti-arrhythmic drugs Exclusion Criteria: * women of childbearing potential unless post- menopausal or surgically sterile * patients hospitalized for heart failure within the 3 months prior to randomization * reversible causes of AF such as pericarditis, thyroid disorders, acute alcohol intoxication, recent major surgical procedures or trauma * recent reversible LV impairment that may be attributed to AF with rapid ventricular response and may improve with introduction of rate control * valvular heart disease requiring surgical intervention * Coronary Artery Disease (CAD) requiring surgical or percutaneous intervention * early post-operative AF (within 3 months of surgery) * previous MAZE or left atrial instrumentation (including ablation and left atrial appendage exclusion) * history of Atrioventricular Node (AVN) ablation * hypertrophic cardiomyopathy * prolonged QT interval * liver failure * renal failure requiring dialysis * social factors that would preclude follow up or make compliance difficult- history of drug, alcohol or substance abuse * contraindications to the use of AADs and/or anticoagulation therapy * Currently enrolled in, or discontinued within the last 30 days from a clinical trial involving an investigational product or non-approved use of a drug or device or concurrently enrolled in any other type of medical research judged not to be scientifically or medically compatible with this study. * severe pulmonary disease * documented intra-atrial thrombus, tumor, or structural abnormality which precludes catheter introduction * unwilling to comply with protocol requirements or deemed by the investigator to be unfit for the study.