Rationale and design of a study assessing treatment strategies of atrial fibrillation in patients with heart failure: The Atrial Fibrillation and Congestive Heart Failure (AF-CHF) trial

Background: Nonrandomized studies suggest that atrial fibrillation is independently associated with increased mortality in patients with heart failure. Whether restoring and maintaining sinus rhythm will have a beneficial impact on cardiovascular mortality in patients with heart failure has never been tested in an adequately powered randomized trial. Objective: The primary objective of the Atrial Fibrillation and Congestive Heart Failure (AF-CHF) trial is to determine whether restoring and maintaining sinus rhythm significantly reduces cardiovascular mortality compared with a rate-control strategy in patients with atrial fibrillation and CHF. Methods: AF-CHF is a prospective multicenter trial (109 centers in Canada, United States, South America, Europe, and Israel), that will randomize 1450 patients with CHF with left ventricular ejection fraction ≤35% and atrial fibrillation to 1 of 2 treatment strategies: (1) rhythm control with the use of electrical cardioversion combined with antiarrhythmic drugs (amiodarone or other class III agents), (2) rate control with the use of β-blockers, digoxin, or pacemaker and AV nodal ablation. Cardiovascular mortality is the primary end point and the intention-to-treat approach the primary method of analysis. We anticipate an 18.75% 2-year cardiovascular mortality in the rate control arm with a 25% mortality reduction in the rhythm control group. Results: As of August 13, 2002, 334 patients have been enrolled from 68 participating centers. Enrollment is expected to be concluded in May 2003 with a minimum follow-up of 2 years. Conclusion: The results of this trial should provide definitive information concerning 2 widely applicable treatment strategies of atrial fibrillation in a large cohort of patients with CHF.