Inotropes and beta-blockers: is there a need for new guidelines?
Beta-adrenergic blocking agents are standard treatment for patients with mild-to-moderate heart failure. When patients receiving beta-blockers decompensate they often need treatment with a positive inotropic agent. The beta-agonist dobutamine may not produce much increase in cardiac output during full-dose beta-blocker treatment and may increase systemic vascular resistance via alpha-adrenergic stimulation. In contrast, phosphodiesterase inhibitors (PDEIs) such as milrinone or enoximone retain full hemodynamic effects during complete beta-blockade because the site of action of PDEIs is beyond the beta-adrenergic receptor and because beta-blockade reverses some of the desensitization phenomena that account for the attenuation of PDEI response in heart failure related to upregulation in G(alphai). Inotrope-requiring subjects with decompensated heart failure who are undergoing long-term therapy with beta-blocking agents should be treated with a type III-specific PDEI, not a beta-agonist such as dobutamine.
Bristow
M R
MR
Department of Cardiology, University of Colorado Health Sciences Center, 4200 E 9th Ave, Denver, CO 80262, USA.
Shakar
S F
SF
Linseman
J V
JV
Lowes
B D
BD
D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D002316:Cardiotonic Agents / Q000627:therapeutic use*; D004359:Drug Therapy, Combination; D006333:Heart Failure / Q000188:drug therapy; D006801:Humans; D009200:Myocardial Contraction / Q000187:drug effects / Q000502:physiology; D010726:Phosphodiesterase Inhibitors / Q000627:therapeutic use; D017410:Practice Guidelines as Topic; D013997:Time Factors; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology
D000319:Adrenergic beta-Antagonists; D002316:Cardiotonic Agents; D010726:Phosphodiesterase Inhibitors