Nonselective Versus Selective β-Adrenergic Receptor Blockade in Congestive Heart Failure

Abstract

Therapy with carvedilol caused significant decreases in systemic and cardiac norepinephrine spillover, an indirect measure of norepinephrine release. Such changes were not observed in patients treated with metoprolol. There was no effect of either agent on sympathetic efferent neuronal discharge to skeletal muscle. These findings suggest that carvedilol, a nonselective beta-blocker, caused its sympathoinhibitory effect by blocking peripheral, prejunctional beta-adrenergic receptors.