Not Found

Find information on medical topics, symptoms, drugs, procedures, news and more, written for the health care professional.

Syndrome X (Microvascular Angina)

By James Wayne Warnica, MD, FRCPC , Professor Emeritus of Cardiac Sciences and Medicine, The University of Calgary

Click here for
Patient Education

Syndrome X is cardiac microvascular dysfunction or constriction causing angina in patients with normal epicardial coronary arteries on angiography.

Patients with cardiac syndrome X have

  • Typical angina that is relieved by rest or nitroglycerin

  • Normal coronary arteriograms (eg, no atherosclerosis, embolism, or inducible arterial spasm)

Some of these patients have ischemia detected during stress testing; others do not. In some patients, the cause of ischemia seems to be reflex intramyocardial coronary constriction and reduced coronary flow reserve. Other patients have microvascular dysfunction within the myocardium: The abnormal vessels do not dilate in response to exercise or other cardiovascular stressors; sensitivity to cardiac pain may also be increased.

This disorder should not be confused with variant angina due to epicardial coronary spasm or with another disorder also called syndrome X, which refers to the metabolic syndrome.

Prognosis is better than for patients with demonstrable coronary artery disease, although symptoms of ischemia may recur for years.

In many patients, beta-blockers relieve symptoms.