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Potassium channel activators in vasospastic angina
J M Lablanche1, C Bauters, E P McFadden
1Service de Cardiologie B et Hémodynamique, Hôpital Cardiologique, Lille, France.
European Heart Journal
|July 1, 1993
Summary
Nicorandil, a potassium channel activator, effectively relaxes vascular smooth muscle and dilates coronary arteries. It is a novel therapeutic option for vasospastic angina, reducing anginal episodes.
Area of Science:
- Cardiovascular Pharmacology
- Vascular Physiology
Background:
- Potassium channel activation promotes vascular smooth muscle relaxation.
- Potassium channel activators exhibit potent coronary vasodilator properties.
Purpose of the Study:
- To evaluate the efficacy of nicorandil in patients with vasospastic angina.
- To assess nicorandil's vasodilatory effects in coronary stenosis and spasm.
Main Methods:
- Investigated nicorandil's vasodilatory action in normal and stenotic coronary segments.
- Assessed nicorandil's effect on methylergometrine-induced and spontaneous coronary spasm.
- Compared nicorandil's efficacy to nifedipine in relieving ergometrine-induced spasm.
- Evaluated oral nicorandil's impact on anginal episode frequency in vasospastic angina patients.
Main Results:
- Nicorandil induced vasodilatation in normal coronary segments and at sites of dynamic coronary stenosis.
- The drug effectively relieved both provoked and spontaneous coronary spasm.
- Nicorandil's efficacy in relieving ergometrine-induced spasm was comparable to nifedipine.
- Oral nicorandil significantly reduced the frequency of anginal episodes in patients with vasospastic angina.
Conclusions:
- Nicorandil is a potent coronary vasodilator with efficacy in vasospastic angina.
- It offers a novel therapeutic option, alone or with other agents, for managing vasospastic angina.
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