(See also Overview of Coronary Artery Disease.)
Many patients with variant angina also have significant fixed obstruction of at least one major coronary artery. Patients with mild or no fixed obstructions have better long-term outcomes than patients with associated severe fixed obstructions.
Diagnosis of variant angina is suspected if ST-segment elevation occurs during the attack. Between anginal attacks, the ECG may be normal or show a stable abnormal pattern.
Confirmation is by provocative testing with ergonovine or acetylcholine, which may precipitate coronary artery spasm. Coronary artery spasm is identified by finding significant ST-segment elevation on ECG or by observation of a reversible spasm during cardiac catheterization. Testing is done most commonly in a cardiac catheterization laboratory.
Average survival at 5 years is 89 to 97%, but mortality risk is greater for patients with both variant angina and atherosclerotic coronary artery obstruction. Risk increases with increasing obstruction.
Usually, sublingual nitroglycerin promptly relieves variant angina. Calcium channel blockers may effectively prevent symptoms. Theoretically, beta-blockers may exacerbate spasm by allowing unopposed alpha-adrenergic vasoconstriction, but this effect has not been proven clinically.
Oral drugs most commonly used are calcium channel blockers:
Although all these drugs relieve symptoms, they do not appear to alter prognosis.