β-Blockers For Congestive Heart Failure

Despite the availability of angiotensin converting enzyme (ACE) inhibitors for patients with congestive heart failure (CHF), mortality and morbidity remains unacceptably high. CHF is thought to progress as a result of activation of endogenous neurohormonal systems which are activated by the initial myocardial injury. The 2 neurohormonal systems which seem to be important in CHF are the sympathetic nervous system (SNS), and the renin-angiotensin-aldosterone system (RAAS). While stimulation of the SNS has important circulatory support functions in the short term, long term activation appears to have deleterious effects on cardiac function and outcomes. The purpose of this article is to review the literature on the use of β-blockers in patients with CHF.The published randomised clinical trials of β-blockers in patients with CHF have shown very promising effects on mortality and morbidity. Several systematic overviews of these trials also suggest beneficial effects on mortality, hospitalisation for CHF, need for transplant, and ejection fraction. The effect of β-blockers on exercise tolerance, New York Heart Association Function Class (NYHA-FC) and quality of life remain equivocal. The recent presentation of the results from several large-scale trials which were terminated early because of significant survival benefit, has removed any concern over the robustness of the mortality data. Available evidence suggests that a wide variety of patients with CHF, including the elderly, should be considered for β-blocker therapy. Caution is warranted in the initiation and titration of therapy, as symptoms of CHF may transiently worsen. Whether all β-blockers are equally efficacious remains unknown.