Prinzmetal's variant angina is a rare form of unstable angina caused by coronary artery vasospasm. It is characterized by recurrent episodes of chest pain (angina) at rest. Patients with Prinzmetal's Angina frequently also have obstructive atherosclerotic coronary artery disease.

Episodes of chest pain often occur in clusters, and a patient may be asymptomatic for weeks or months between attacks. These attacks typically resolve spontaneously, and progession to heart attack (myocardial infarction) is rare except in cases of prolonged spasm or in patients in whom vasospasm complicates multivessel obstructive coronary artery disease.