Coronary arteries on the outer surface of the heart branch into many smaller vessels, which supply blood directly to the heart’s muscle tissue.

Normally, these vessels expand when the heart needs more blood -- during exercise or stress.

With small vessel heart disease, the vessels don’t expand properly and may even get smaller during physical or emotional stress. This lack of dilation can cause symptoms similar to a heart attack.

While reduced blood flow to the heart can cause chest pain, pressure or discomfort, sometimes the symptoms of small vessel disease in women are more subtle, such as fatigue during everyday activities or mental stress.

Diagnosing the condition can be tricky because the standard tool for visualizing blocked arteries -- coronary angioplasty -- doesn’t detect small vessel problems.

When heart disease is suspected and not evident with traditional diagnostic tests, women should consider finding a clinic or hospital with expertise in small vessel heart disease or cardiovascular disease in women.

Specialized tests can identify the problem. The earlier it’s discovered, the better the chances of preventing heart damage.

Standard treatments for coronary heart disease, such as angioplasty, stenting and bypass surgery, aren’t used to treat small vessel heart disease.

Instead, the treatment focuses on reducing risk through managing high blood pressure, diabetes and high cholesterol. Exercising, maintaining a healthy weight and not smoking also are important.

Mayo Clinic Women’s HealthSource is published monthly to help women enjoy healthier, more productive lives.

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