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Inotropes and beta-blockers: is there a need for new guidelines?
M R Bristow1, S F Shakar, J V Linseman
1Department of Cardiology, University of Colorado Health Sciences Center, 4200 E 9th Ave, Denver, CO 80262, USA.
Journal of Cardiac Failure
|October 18, 2001
Summary
For heart failure patients on beta-blockers, phosphodiesterase inhibitors (PDEIs) are more effective than dobutamine. PDEIs maintain hemodynamic benefits during beta-blockade, unlike beta-agonists.
Area of Science:
- Cardiology
- Pharmacology
Background:
- Beta-adrenergic blocking agents are standard for mild-to-moderate heart failure.
- Decompensation in patients on beta-blockers often necessitates positive inotropic agents.
Purpose of the Study:
- To compare the efficacy of phosphodiesterase inhibitors (PDEIs) versus beta-agonists in heart failure patients receiving beta-blockers.
Main Methods:
- The study discusses the pharmacological mechanisms of PDEIs and beta-agonists in the context of beta-blockade.
- It analyzes the hemodynamic effects of these agents during complete beta-blockade.
Main Results:
- Beta-agonists like dobutamine may have limited efficacy and increase systemic vascular resistance during full beta-blockade.
- Phosphodiesterase inhibitors (PDEIs) retain full hemodynamic effects due to their action site being beyond the beta-adrenergic receptor.
- Beta-blockade can reverse desensitization phenomena, enhancing PDEI response.
Conclusions:
- Type III-specific PDEIs are recommended over beta-agonists for inotrope-requiring patients with decompensated heart failure on long-term beta-blocker therapy.
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