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[The effect of captopril in nitrate tolerance]
1Abteilung für Kardiologie, Universität Frankfurt/Main.
Deutsche Medizinische Wochenschrift (1946)
|February 19, 1993
Summary
Angiotensin-converting-enzyme (ACE) inhibitors like captopril can counteract nitrate tolerance in patients with coronary artery disease. Combining ACE inhibitors with nitrates improves anti-ischemic effects, even when tolerance develops.
Area of Science:
- Cardiology
- Pharmacology
Background:
- Nitrate tolerance is a common issue in managing coronary artery disease.
- Angiotensin-converting-enzyme (ACE) inhibitors are used to treat cardiovascular conditions.
Purpose of the Study:
- To investigate if ACE inhibitors can overcome nitrate tolerance.
- To assess the combined anti-ischemic effects of ACE inhibitors and nitrates.
Main Methods:
- 15 male patients with significant coronary artery stenosis underwent ergometric tests.
- Medications administered included captopril (an ACE inhibitor) and nitrate patches.
- S-T segment depression during exercise and recovery was measured to assess cardiac ischemia.
Main Results:
- Captopril alone reduced S-T segment depression.
- Nitrate application initially decreased S-T segment depression, but tolerance developed with continuous use.
- In the presence of nitrate tolerance, captopril administration still significantly reduced S-T segment depression.
- The combined effect of captopril and residual nitrate action was additive.
Conclusions:
- ACE inhibitors, such as captopril, can effectively counteract nitrate tolerance in patients with coronary artery disease.
- Combining ACE inhibitors with nitrates offers additive anti-ischemic benefits, enhancing treatment efficacy.
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