Expert Review: Heart Failure

Efficacy of β blockers in patients with heart failure plus atrial fibrillation: an individual-patient data meta-analysis

 

Background and knowledge gap
According to current guidelines, a rhythm-control strategy (including pharmacological or electrical cardioversion) in patients with chronic HF, has not been demonstrated to be superior to a rate-control strategy in reducing mortality or morbidity. Preference of beta-blockers over other rate-control medications has been extrapolated from results of patients in sinus rhythm3,4.

Aim of the Study
The study aimed to test the efficacy and safety of β blockers in patients with HF and concomitant AF.
The primary outcome was all-cause mortality.
Major secondary outcomes were cardiovascular death, the composite of all-cause mortality and cardiovascular hospitalisation, and non-fatal stroke.
Methods
The authors of the study performed a meta-analysis of individual-patient data from 10 randomized controlled trials of the comparison of beta-blockers versus placebo in HF. Baseline electrocardiogram was used to establish the diagnosis of sinus rhythm and AF.

Results
The researchers found that, of the 18,254 patients assessed, 76% had sinus rhythm and 17% had AF at baseline. Crude death rates over a mean follow-up of 1.5 years were 16% in patients with sinus rhythm and 21% (633 of 3,064) in patients with AF. The use of beta blockers was associated with a 27% reduction in the risk for all-cause mortality for patients with HF in sinus rhythm (p<0.001), but patients with AF had a non-significant 3% reduction. Similarly, patients with HF in sinus rhythm who were treated with beta blockers had significant reductions in the risk for cardiovascular hospital admission, HF-related hospital admission, and composite clinical outcomes, whereas patients with HF and AF did not. In addition for patients who started out in sinus rhythm, allocation to beta blockers was also associated with a 33% reduction in the adjusted odds of incident AF (from 6% without beta blockers to 4% with beta blockers).
The lack of efficacy of beta-blockers extended to all subgroups of AF, including age, sex, left ventricular ejection fraction, New York Heart Association class, heart rate, and baseline medical therapy

Clinical Impact:
The results of this study suggest that, for the primary reason of preventing major adverse cardiovascular outcomes in patients with chronic HF and reduced ejection fraction, beta-blockers do not seem to be effective in patients with AF and should no longer be regarded as standard therapy to improve prognosis. However, this therapy proved to be safe, with no increase in mortality or hospital admission rates. This finding should reassure clinicians, particularly for patients with another indication for beta-blockers (eg, myocardial infarction or the need for rate control of rapid AF with ongoing symptoms).
Further research comparing beta-blockers with other rate-control medications in this common and increasingly important group of patients is needed.

Corresponding author from original paper
Dr Dipak Kotecha
University of Birmingham Centre for Cardiovascular Sciences, Medical
School, Vincent Drive, Edgbaston, Birmingham
B15 2TT, UK
Electronic address: d.kotecha@bham.ac.uk

References
1.- Maisel WH, Stevenson LW. Atrial fi brillation in heart failure: epidemiology, pathophysiology, and rationale for therapy. Am J Cardiol 2003; 91: 2D–8D

2.- Lewis RV, McMurray J, McDevitt DG. Effects of atenolol, verapamil, and xamoterol on heart rate and exercise tolerance in digitalised patients with chronic atrial fibrillation. J Cardiovasc Pharmacol 1989;13:1–6.

3.- Camm AJ, Kirchhof P, Lip GYH, Schotten U, Savelieva I, Ernst S et al. Guidelines for the management of atrial fi brillation: The Task Force for the Management of Atrial Fibrillation of the European Society of Cardiology (ESC). Eur Heart J 2010; 31: 2369–429.

4.- McMurray JJ, Adamopoulos S, Anker SD, Auricchio A, Böhm M, Dickstein K et al. Task Force for the Diagnosis and Treatment of Acute and Chronic Heart Failure 2012 of the European Society of Cardiology (ESC). Eur J Heart Fail. 2012;14(8):803-69.

 

 

Citation: Citation: Kotecha D, Holmes J, Krum H, Altman DG, Manzano L, Cleland JG, et al; on behalf of the Beta-Blockers in Heart Failure Collaborative Group. Efficacy of β blockers in patients with heart failure plus atrial fibrillation: an individual-patient data meta-analysis. Lancet. 2014 doi: 10.1016/S0140-6736(14)61373-8. [Epub ahead of print]

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