Testing for Heart Disease

After taking a careful medical history and doing a physical exam, the doctor may use some tests to see how advanced the heart disease is. The only certain way to diagnose and assess the extent of coronary heart disease is coronary angiography (see below); other tests can indicate a problem but do not show exactly where it is.

An examination for heart disease may include the following tests:

• An electrocardiogram (EKG) is a graphic record of the electrical activity of the heart as it contracts and rests. Abnormal heartbeats and some areas of damage, inadequate blood flow, and heart enlargement can be detected on the records.

• A stress test (also called a treadmill test or exercise ECG) is used to record the heartbeat during exercise. This is done because some heart problems only show up when the heart is working hard.  In the test, an ECG is done before, during, and after exercising on a treadmill; breathing rate and blood pressure may be measured as well. Exercise tests are useful but are not completely reliable; false positives (showing a problem where none exists) and false negatives (showing no problem when something is wrong) are fairly common.

• Nuclear scanning is sometimes used to show damaged areas of the heart and expose problems with the heart's pumping action. A small amount of radioactive material is injected into a vein, usually in the arm. A scanning camera records the nuclear material that is taken up by heart muscle (healthy areas) or not taken up (damaged areas).

• Coronary angiography (or arteriography) is a test used to explore the coronary arteries. A fine tube (catheter) is put into an artery of an arm or leg and passed through the tube into the arteries of the heart. The heart and blood vessels are then filmed while the heart pumps. The picture that is seen, called an angiogram or arteriogram, will show problems such as a blockage caused by atherosclerosis.