Atrial fibrillation is the most common sustained cardiac arrhythmia affecting 5% of people older than 65 years. It is associated with a 5 times increase of the risk of stroke in patients who are not receiving anticoagulant therapy and a doubling of the rate of death in all patients.~Congestive heart failure (CHF) and atrial fibrillation (AF) often co-exist, where one condition is promoting the development of the other and worsens its condition.~It is the purpose of the study to show the benefit of the endocardial catheter ablation by pulmonary vein isolation in patients with persistent (for a minimum of 1 week to a maximum of 1 year duration) or longstanding persistent (for a minimum of 1 year to a maximum of 4 years) atrial fibrillation, low LVEF (<=35%) and requiring ICD or CRT-D therapy compared to the best medical treatment with antiarrhythmic drugs.~Patients meeting the inclusion and exclusion criteria will be randomized in a 1:1 fashion in an unblinded, parallel arm treatment format to either drug therapy (directed at rate or rhythm control) or catheter ablation.~All therapies will be established and optimized in a 3 month treatment initiation phase (Blanking Period) starting with randomization. For all morbidity and mortality end-points, intention-to-treat analysis will begin at randomization. Efficacy with respect to AF treatment will be established for long-term follow up beginning after 3-month initiation phase.~Improvement of LVEF within 12 month is the primary endpoint of this study. The transthoracic echocardiographic (TTE) assessment at enrollment, discharge and 12 months follow-up follows a standardized protocol. The assessments are analyzed, calculated and expressed by an independent Core Lab.
It is the purpose of the study to show the benefit of the endocardial catheter ablation by pulmonary vein isolation in patients with persistent or longstanding persistent atrial fibrillation, low LVEF and requiring ICD or CRT-D therapy compared to the best medical treatment with antiarrhythmic drugs.