Blood and Urine Tests. Blood and urine tests that indicate a risk for coronary artery disease and heart attack include those for cholesterol, homocysteine, the protein albumin, and blood clotting factors, especially fibrinogen.

Electrocardiograms and Echocardiograms. An electrocardiogram (ECG) measures and records the electrical activity of the heart during an angina attack. Between 25% and 50% of people who suffer from angina or have silent ischemia, however, have normal ECG readings. An echocardiogram uses ultrasound images of the heart. This test is more expensive than an ECG, but it can detect muscle weakness from a prior heart attack or motion abnormalities. Echocardiograms may be more useful for women than ECGs.

Stress Test. A stress test (exercise tolerance test) monitors the patient's heart rhythms, blood pressure, and clinical status while the patient walks on a treadmill or rides a stationary bicycle. Exercise continues until the heart is beating at least 85% of its maximum rate or until heart rhythm abnormalities, angina, fatigue, or other symptoms of heart trouble occur. An ECG is usually used to monitor heart rhythms during a stress test, although an echocardiogram may be used. Failure to reach the target heart rate may be a sign of a risk for heart attack and angina in people with coronary artery disease or even a predictor for coronary artery disease in people without a current problem. Unfortunately, only about 65% of patients are diagnosed correctly using an ECG test, and the accuracy is even worse for women. (Using an echocardiogram instead of an ECG appears to be a more accurate procedure for women.) About 10% of healthy patients, particularly younger people, will have abnormal test results (false positive). Because stress tests can precipitate angina, irregular heart rhythms, or, rarely, even heart attacks, they must be performed under careful supervision. For patients who cannot exercise, the drug dobutamine may be given, which simulates the stress of exercise.