β-Adrenergic Blockers in Heart Failure: Review of Mechanisms of Action and Clinical Outcomes

Abstract
Better understanding of the pathophysiology of heart failure has shifted the treatment of heart failure away from enhancing myocardial contractility to a new paradigm that targets the root cause of disease progression by blocking the adverse effects of excessive neurohormonal activation. β-Adrenergic receptor-blockers have emerged as a cornerstone in the management of symptomatic heart failure. This article reviews the normal functioning of the β-adrenergic pathway, the consequences of hyperadrenergism on this crucial signaling pathway, and the mechanisms by which chronic β-blocker therapy reverses these abnormalities. The clinical evidence from controlled trials of the efficacy of β-blockers in treating heart failure is summarized. Finally, the concomitant use of β-blockers and positive inotropic agents in advanced heart failure is discussed.