What Does Stress Testing Show?

Stress testing gives your doctor information about how your heart works during physical stress (exercise) and how healthy your heart is.

A standard exercise stress test uses an EKG (electrocardiogram) to monitor changes in your heart's electrical activity. Imaging stress tests take pictures of blood flow in various parts of your heart. They also show your heart valves and the movement of your heart muscle.

Both types of stress tests are used to look for signs that your heart isn't getting enough blood flow during exercise. Abnormal test results may be due to coronary heart disease (CHD) or other factors, such as a lack of physical fitness.

If you have a standard exercise stress test and the results are normal, no further testing or treatment may be needed. But if your test results are abnormal, or if you're physically unable to exercise, your doctor may want you to have an imaging stress test or other tests.

Even if your standard exercise stress test results are normal, your doctor may want you to have an imaging stress test if you continue having symptoms (such as shortness of breath or chest pain).

Imaging stress tests are more accurate than standard exercise stress tests, but they're much more expensive.

Imaging stress tests show how well blood is flowing in the heart muscle and reveal parts of the heart that aren't contracting strongly. They also can show the parts of the heart that aren't getting enough blood, as well as dead tissue in the heart, where no blood flows. (A heart attack can cause some tissue in the heart to die.)

If your imaging stress test suggests significant CHD, your doctor may want you to have more testing and/or treatment.