Cardiac Syndrome X

Your Care Explained > Conditions and Diagnoses : Cardiac Syndrome X

Cardiac syndrome X is a name cardiologists have given to a baffling condition that occurs primarily in women. It was coined to describe angina that persists even though coronary angiography has failed to show coronary artery disease. However, there is increasing evidence that cardiac syndrome X is actually microvascular disease.

What Causes Cardiac Syndrome X?

In the past, researchers proposed a couple of theories about the cause of cardiac syndrome X. One was that it had to do with how patients feel pain; another was that it is linked to low levels of estrogen. New research has shown that cardiac syndrome X is most likely a symptom of microvascular disease.

Diagnosing Cardiac Syndrome X

Cardiac syndrome X is usually diagnosed by many of the same tests used to diagnose coronary artery disease, including electrocardiogram (ECG) or an exercise stress test. If either test indicates ischemic heart disease, coronary angiography is performed to check for blockages in the coronary arteries. If your doctors do not see a coronary artery obstruction they will perform coronary flow reserve studies during the same procedure. Coronary flow reserve studies do not give a direct view of the tiny vessels; instead, they measure the blood flowing into the coronary arteries. Microvascular disease is diagnosed when the tiny vessels that feed into the coronary arteries are narrowed or do not dilate enough to provide an adequate blood supply to the heart.

Treating Cardiac Syndrome X

Because women with this disorder don’t have distinct arterial blockages, treatment is usually similar to that for microvascular disease—lifestyle changes, including a heart-healthy diet, exercise, smoking cessation and, if needed, medication to control blood pressure and cholesterol.

Nutrition and Prevention

Reference these links for information on how to prevent heart disease and how to live a healthy lifestyle.

Date Last Modified: January 21, 2011

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