Early reduction of neurohumoral factors plays a key role in mediating the efficacy of β-blocker therapy for congestive heart failure

This study examined the role played by neurohumoral factors in mediating the effects of β-blocker therapy for congestive heart failure. Fifteen patients with congestive heart failure underwent β-blocker therapy. Plasma norepinephrine and α-atrial natriuretic peptide concentrations decreased 2 weeks after initiation of β-blocker therapy. Decrease in plasma norepinephrine level persisted for 6 months. Lymphocyte β-adrenoceptor density increased 2 weeks after therapy but was not increased 6 months later. Left ventricular ejection fraction was unchanged 2 weeks after therapy, but it increased 6 months after introduction of β-blockers. Plasma norepinephrine level decreased 2 weeks after the therapy in the responders (increase in ejection fraction>0.10) but not in the nonresponders. Thus early reduction of neurohumoral factor levels preceded the late improvement of left ventricular contractile function and may therefore be partly responsible for the efficacy of β-blocker therapy for congestive heart failure.