Evidence for the Benefits of Beta Blockers
ACE inhibitors had been shown to have significant benefits for survival before beta blockers were implicated as a potential heart failure therapy. It would have been unethical to stop ACE inhibitor treatment in order to investigate a new therapeutic agent, which had not been proven to improve clinical outcome. Therefore, all clinical trials set up to study the effects of beta blockers in heart failure patients used subjects who were already receiving treatment with ACE inhibitors.
Three major clinical trials, and sever-al meta-analyses, have demonstrated the benefits of beta blockade.[8,9,10,11,12,13,14,15] Cardiac Insufficiency Bisoprolol Study (CIBIS II), Metoprolol CR/XL Randomised Interventional Trial in Congestive Heart Failure (MERIT-HF) and Carvedilol Prospective Randomised Cumulative Survival (COPERNICUS) examined the effects of treatment with bisoprolol, metoprolol and carvedilol, respectively, in patients with chronic heart failure who were already receiving ACE inhibitors and diuretics. The beneficial effects of beta-blocker treatment were so apparent in all three trials that they were prematurely terminated. All-cause mortality was reduced by a further 34-35% over the mortality reduction achieved by ACE inhibitor treatment alone. The incidence of sudden death was also reduced in the CIBIS II and MERIT-HF trials, an effect which had not been seen with ACE inhibitors, where the mortality benefit had predominantly come from a reduction in deaths from disease progression.[3,4] A meta-analysis of beta-blocker trials also showed hospitalization rates to be significantly reduced for patients receiving beta blockers.[11]
Other studies have shown that beta blockers have the ability to reverse some degree of heart damage. After three months of treatment with maximally tolerated doses, bisoprolol was shown to have significantly improved left ventricular ejection fraction and reversed the left ventricle remodelling associated with chronic heart failure.[16]
Since the benefits of beta-blocker treatment are now so apparent, a study is currently underway to investigate whether it would be more beneficial to give beta blockers rather than ACE inhibitors as first line in the standard course of treatment.[17]
Br J Cardiol. 2005;12(4):313-317. © 2005 Sherborne Gibbs Ltd.
None declared.
Cite this: Additional Benefits Versus Practicalities of Beta-Blocker Use in CHF Patients: The 'Some Is Better Than None' Rule - Medscape - Jul 01, 2005.
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