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Cardiac syndrome X: Angina pectoris with normal coronary arteries

Imran Chaudhary, MD
Section Editor
Juan Carlos Kaski, DSc, MD, DM (Hons), FRCP, FESC, FACC, FAHA
Deputy Editor
Gordon M Saperia, MD, FACC


Cardiac syndrome X is a clinical syndrome with the following characteristics:

Angina or angina-like chest pain with exertion. (See "Angina pectoris: Chest pain caused by myocardial ischemia", section on 'Typical qualities of anginal pain'.)

Electrocardiographic evidence of ST segment depression on treadmill exercise testing. (See "Exercise ECG testing: Performing the test and interpreting the ECG results", section on 'ST segment depression'.)

Normal coronary angiography, with no spontaneous or inducible epicardial coronary artery spasm on ergonovine or acetylcholine provocation, such as that seen with variant angina. (See "Vasospastic angina".)

Noncardiac causes of chest pain must be excluded before the diagnosis of cardiac syndrome X can be made. (See "Outpatient evaluation of the adult with chest pain", section on 'Etiologies'.)


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Literature review current through: May 2017. | This topic last updated: May 24, 2017.
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