Coronary Vasospasm & Angina with Normal Coronary Arteriograms

Key Features

• Precordial chest pain, often occurring at rest during stress or without known precipitant, relieved rapidly by nitrates

• ECG evidence of ischemia during pain, sometimes with ST-segment elevation, including by Holter monitor

• No significant obstruction of major coronary vessels

• Coronary spasm that responds to intracoronary nitroglycerin or calcium channel blockers

Clinical Findings

• Spasm of the large coronary arteries with resulting decreased coronary blood flow

  • May occur spontaneously or induced by exposure to cold, emotional stress, or vasoconstricting medications and substances, such as ergots and cocaine

  • May occur both in normal and in stenosed coronary arteries

• Ischemia may be silent or result in angina pectoris or even infarction

• Prinzmetal (variant) angina

  • Chest pain occurs without the usual precipitating factors and is associated with ST-segment elevation rather than depression

  • The associated ischemia usually results from coronary vasoconstriction

  • It tends to involve the right coronary artery and there may be no fixed stenoses

  • Myocardial ischemia may also occur in patients with normal coronary arteries as a result of disease of the coronary microcirculation or abnormal vascular reactivity

  • Often affects women under 50 years of age

  • Characteristically occurs in the early morning or on awakening from sleep and is associated with arrhythmias or conduction defects

Diagnosis

• Prinzmetal (variant) angina

  • May be diagnosed by challenge with ergonovine (a vasoconstrictor)

  • However, results of ergonovine provocation are not specific and it entails risk

• Patients with chest pain associated with ST-segment elevation should undergo coronary arteriography to determine whether fixed stenotic lesions are present

Treatment

• If fixed stenotic lesions are present, aggressive medical therapy or revascularization is indicated

• If significant stenotic lesions are absent and spasm is suspected, avoidance of precipitants such as cigarette smoking and cocaine is the top priority

• Treatment of coronary vasospasm episodes generally involves nitrates

• Prophylaxis of episodes can be achieved with both nitrates and calcium channel blockers (including long-acting nifedipine, diltiazem, or amlopidine)

• Beta-blockers

  • Can exacerbate coronary vasospasm by allowing unopposed alpha-1-mediated vasoconstriction

  • May have a role in patients in whom spasm is associated with fixed stenoses