A new scoring system used in treadmill testing may help physicians improve their accuracy in diagnosing heart disease, according to a study presented at the American Heart Association Scientific Sessions.

Treadmill tests have been used for decades to help diagnose atherosclerosis, the narrowing of coronary arteries that can lead to a heart attack or stroke.

The treadmill test, also called an exercise stress test, helps physicians learn how well an individual's heart handles physical exertion. The test measures heart rate, blood pressure and the electrical function of the heart as the patient walks on a treadmill.

The speed at which the patient walks gradually increases, requiring the body to use more oxygen and the heart to pump harder. Treadmill test results can show if there's a lack of blood supply through the arteries that go to the heart.

A diagnosis of heart disease is made by using results of the treadmill test, along with other "clinical" information, such as medical problems and risk factors.

An angiogram - an X-ray of the blood vessel - can be used to confirm the diagnosis, said Dr. Victor Froelicher of Stanford University Medical School, lead researcher of the study.