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Intracoronary Acetylcholine Provocation Testing for Assessment of Coronary Vasomotor Disorders
06:39

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Published on: August 18, 2016

Alpha-adrenoceptor-mediated coronary artery spasm

D L Levene, M R Freeman

    JAMA
    |August 30, 1976
    PubMed

    Insights

    Coronary artery spasm, mediated by alpha-adrenoceptors, can mimic organic lesions during arteriography. This condition may contribute to angina pectoris, with alpha-blockade improving symptoms.

    Area of Science:

    • Cardiology
    • Pharmacology

    Background:

    • Angina pectoris can be caused by coronary artery stenosis.
    • Coronary artery spasm is a potential cause of chest pain.
    • Nitrate therapy is commonly used to treat angina.

    Observation:

    • Selective coronary arteriography revealed proximal stenosis in a patient with angina pectoris.
    • The stenosis was unresponsive to nitrate therapy.
    • Repeat arteriography showed increased narrowing, suggesting spasm.

    Findings:

    • Intravenous phentolamine hydrochloride abolished the observed 90% stenosis.
    • Prolonged alpha-adrenoceptor blockade with phenoxybenzamine hydrochloride improved exercise tolerance and ECG abnormalities.
    • Control patients receiving placebo did not show similar improvements.

    Implications:

    • Alpha-adrenoceptor-mediated coronary artery spasm can mimic organic coronary artery disease.
    • This type of spasm may be a significant factor in the pathogenesis of angina pectoris in some individuals.
    • Alpha-adrenoceptor blockade presents a potential therapeutic strategy for specific cases of angina.

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