ABSTRACT
Activation of the adrenergic nervous system acts in the short term to compensate for reduced cardiac performance in heart failure and attempts at treating heart failure centered initially on augmenting adrenergic support to the failing heart. ß-blockers are a heterogeneous group of agents which differ substantially in their properties, their biological effects, and perhaps their impact on clinical outcomes. ß-blockers can be divided into three classes based on their ß-adrenergic receptor blocking profiles, vasodilating activity, and ancillary properties. Acute administration of ß-blockers slows the heart rate and decreases myocardial contractility as a result of reducing adrenergic support for the failing heart. This may result in a clinical worsening of heart failure when introducing ß-blockers in patients with heart failure. The long-term administration of ß-blockers produces a diverse range of effects on myocardial structure and function which become evident after several weeks of therapy, and is usually manifest by an improvement in measures of clinical outcome.
