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Updated: Jan 2, 2026
08:05
Cardiac Response to β-Adrenergic Stimulation Determined by Pressure-Volume Loop Analysis
Published on: May 19, 2021
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Summary
Bisoprolol, a beta-blocker, effectively reduced blood pressure and heart rate in angina patients. However, higher doses (30-40 mg) increased airway resistance and decreased lung function, indicating potential respiratory risks.
Area of Science:
- Pharmacology
- Cardiology
- Pulmonology
Background:
- Angina pectoris and chronic obstructive bronchitis often coexist.
- Beta-adrenoceptor antagonists are commonly used for cardiovascular conditions.
- The respiratory effects of beta-blockers in patients with obstructive lung disease require careful evaluation.
Purpose of the Study:
- To investigate the dose-dependent effects of bisoprolol on cardiovascular and respiratory parameters.
- To assess the safety of bisoprolol in patients with both angina pectoris and chronic obstructive bronchitis.
Main Methods:
- An open-label study involving 16 patients with angina pectoris and chronic obstructive bronchitis.
- Administration of single oral doses of bisoprolol ranging from 5 to 40 mg.
- Monitoring of blood pressure (BP), heart rate (HR), airway resistance (AWR), and forced expiratory volume in 1 s (FEV1).
Main Results:
- Bisoprolol consistently reduced BP and HR across all tested doses.
- Doses of 5-20 mg bisoprolol did not significantly alter AWR or FEV1.
- Doses of 30-40 mg bisoprolol led to increased AWR and decreased FEV1, suggesting bronchoconstriction.
Conclusions:
- Bisoprolol demonstrates cardiovascular benefits at therapeutic doses.
- Higher doses of bisoprolol may pose a risk of bronchospasm in patients with COPD.
- Careful dose selection and monitoring are crucial when prescribing bisoprolol to patients with comorbid respiratory conditions.
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