β-Adrenergic Receptor Blockade in Chronic Heart Failure

Abstract

The failing human heart is adrenergically activated,^{4 5 6} which helps to maintain cardiac performance over the short term by increasing contractility and heart rate. In contrast, in the resting state there is no adrenergic support of normally functioning human left ventricles.⁶ Multiple lines of evidence^{7 8 9} indicate that it is the increase in cardiac adrenergic drive rather than an increase in circulating norepinephrine that is both initially supportive and then ultimately damaging to the failing human heart.