Related Experiment Videos
[The effect of intracoronary infused captopril on luminal width in coronary stenosis]
R Bettinger1, B Winkelmann, S Schupp
1Abteilung für Kardiologie, Universität Frankfurt/Main.
Insights
Captopril did not acutely dilate coronary artery stenosis in patients with stable angina. This suggests that angiotensin-converting-enzyme inhibitors may not directly affect coronary stenosis diameter via intracoronary infusion.
Area of Science:
- Cardiology
- Pharmacology
Background:
- Angiotensin-converting-enzyme (ACE) inhibitors are used for anti-ischaemic and anti-anginal effects.
- The direct mechanism of their action on coronary stenosis is not fully understood.
Purpose of the Study:
- To investigate whether intracoronary infusion of captopril can cause acute dilatation of coronary stenosis.
- To elucidate the mechanism of anti-ischaemic and anti-anginal action of ACE inhibitors.
Main Methods:
- A randomized, double-blind study was conducted.
- 30 patients with stable angina and significant coronary stenosis received either intracoronary captopril (0.5 mg) or placebo.
- Coronary stenosis diameter was measured before and after infusion.
Main Results:
- Intracoronary captopril did not significantly alter the diameter of coronary stenosis.
- No significant difference in stenosis diameter was observed between the captopril and placebo groups.
- The lack of effect might be due to insufficient liberation of endothelium-derived relaxing factor in arteriosclerotic segments.
Conclusions:
- Intracoronary captopril does not acutely dilate coronary stenosis in patients with stable angina.
- The anti-anginal effects of ACE inhibitors may not be mediated by direct vasodilation of stenotic coronary arteries.
- Further research is needed to understand the precise mechanisms of ACE inhibitors in managing angina.
Abstract:
To elucidate the mechanism of anti-ischaemic and anti-anginal action of angiotensin-converting-enzyme inhibitors, a randomized double-blind study was undertaken in 30 consecutive patients (27 men, 3 women; mean age 58 [28-70] years) with stable angina and at least 50%, angiographically well demonstrated, stenosis of one of the main coronary artery branches. They received an intracoronary infusion of either 0.5 mg captopril (n = 16) or of a placebo (n = 14) to see whether in this form of application the drug could cause an acute dilatation of a coronary stenosis. The diameter before captopril administration was 1.40 +/- 0.63 mm, while 1, 5 and 10 min after infusion it was 1.49 +/- 0.58 mm, 1.30 +/- 0.54 mm and 1.41 +/- 0.59 mm (not significant). There was also no significant difference between captopril and the placebo. The absence of effect with captopril may be due to insufficient liberation of endothelium-derived relaxing factor in an arteriosclerotic coronary segment.