Study designs of evaluations included in the review
Randomised controlled trials (RCTs) using a parallel design were eligible.
Specific interventions included in the review
Studies comparing beta-blockers with placebo were eligible. Concomitant treatment with angiotensin-converting enzyme inhibitors was provided to the majority of patients in both study groups. The beta-blockers used included bisoprolol, metoprolol, bucindolol, carvedilol and nebivolol.
Participants included in the review
Studies of patients with congestive HF were eligible. Patients with AF at baseline were excluded from the analysis. In the included studies HF was secondary to coronary artery disease or idiopathic dilated cardiomyopathy. The mean left ventricular ejection fraction ranged from 20 to 36% and the New York Heart Association class from I to IV. The mean age of the participants varied from 57 to 76 years.
Outcomes assessed in the review
Eligible studies had to report the incidence of AF. Follow-up ranged from 0.5 to 2 years.
How were decisions on the relevance of primary studies made?
Two reviewers independently selected the studies.