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Updated: Jul 17, 2026
06:32
Evaluation of Coronary Flow Reserve After Myocardial Ischemia Reperfusion in Rats
Published on: June 28, 2019
Does the beta-blocker nebivolol increase coronary flow reserve?
Mario Togni1, Francesco Vigorito, Stephan Windecker
1Swiss Cardiovascular Center Bern, Inselspital, CH-3010 Bern, Switzerland. mario.togni@insel.ch
Cardiovascular Drugs and Therapy
|January 20, 2007
Summary
Nebivolol, a beta-blocker, improves coronary flow reserve (CFR) by affecting resting and maximal coronary blood flow. This study investigated its impact on coronary perfusion in healthy individuals and coronary artery disease patients.
Area of Science:
- Cardiology
- Pharmacology
- Vascular Biology
Background:
- Nebivolol selectively blocks beta1-adrenergic receptors, enhancing nitric oxide (NO) release.
- The effect of nebivolol-induced NO increase on coronary perfusion remains unclear.
- This study aimed to assess nebivolol's impact on coronary flow reserve (CFR) and collateral flow.
Purpose of the Study:
- To evaluate the effect of nebivolol on coronary flow reserve (CFR) in healthy controls and patients with coronary artery disease (CAD).
- To assess the impact of nebivolol on collateral flow in CAD patients.
- To investigate the relationship between nebivolol's effects and myocardial oxygen consumption.
Main Methods:
- Coronary flow velocity was measured using Doppler-flow wire in 10 controls and 8 CAD patients.
- CFR was determined by the ratio of maximal hyperemic flow to resting flow after intracoronary nebivolol administration.
- Collateral flow index (CFI) was assessed in CAD patients after inducing coronary stenosis.
Main Results:
- Nebivolol significantly increased CFR in both controls and CAD patients.
- CFR increased from 2.1+/-0.4 to 2.6+/-0.5 in CAD patients (p<0.05) and from 3.0+/-0.6 to 4.0+/-0.1 in controls (p<0.01).
- CFI decreased significantly with nebivolol, correlating with heart rate and rate-pressure product.
Conclusions:
- Intracoronary nebivolol administration increases CFR in both healthy individuals and CAD patients.
- The increase in CFR is attributed to reduced resting flow in controls and increased maximal flow in CAD patients.
- Nebivolol's reduction in CFI suggests a decrease in myocardial oxygen demand.
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