What is the rationale for using beta-blockers in symptomatic heart failure with reduced ejection fraction?

• A. They increase myocardial contractility to improve output.
• B. They reduce mortality by attenuating chronic sympathetic overactivity and improve remodeling.
• C. They primarily vasodilate the pulmonary vasculature.
• D. They rapidly diurese to reduce preload.

Answer: (B)

Beta-blockers in systolic heart failure work by countering the harmful chronic sympathetic activation that the failing heart triggers to maintain perfusion. In heart failure, sustained high sympathetic drive increases heart rate and Myocardial oxygen demand, promotes adverse remodeling, and raises the risk of dangerous arrhythmias. Blocking beta-adrenergic receptors reduces heart rate and the harmful effects of catecholamines, which over time slows or even reverses remodeling and lowers mortality. The benefit comes from changing the disease trajectory rather than just providing symptomatic relief. They’re started once the patient is stabilized and titrated up carefully, since the initial effect can slightly decrease contractility, but the long-term outcome improves. They’re not primarily diuretics or pulmonary vasodilators, which handle preload or afterload differently.