Although coronary heart disease claims the lives of women and men in nearly equal numbers, it’s the leading cause of death among women in the United States. The cardiac stress test is an important tool in diagnosing heart disease. Early diagnosis increases the number of treatment options and the probability of a good outcome. A cardiac stress test evaluates the blood supply to the heart muscle. It can be done by either exercise or "chemical" methods.

There are two types of exercise stress tests:

• Regular—The patient walks on a treadmill while his or her heart and blood pressure are monitored. The treadmill’s speed and incline are increased slowly in an effort to reach a predetermined heart rate. Most people are on the treadmill for five to 10 minutes. Electrocardiograms (EKGs), which allow the physician to evaluate the blood supply to the heart during exercise, are obtained throughout the test.

• Nuclear, or Cardiolite—This is a two-day test. The first day is similar to a regular stress test but includes an intravenous (IV) injection of Cardiolite. Cardiolite allows physicians to evaluate the blood flow to the heart by using a heart scan that is done after the test’s treadmill portion. On the second day of the test, the physician injects the patient with Cardiolite again and takes a resting heart scan.

Chemical stress tests are available for people unable to walk on a treadmill or walk fast enough to raise their heart rate to the target number. In a chemical stress test, the heart’s arteries are expanded with an IV medication. The physician then injects the patient with Cardiolite and performs a heart scan. The scan determines whether the heart arteries are expanding normally. Like the nuclear exercise stress test, the chemical test isn’t complete until the resting heart scan has been obtained on the second day.

Patients are usually instructed to fast (no food or drink) for six hours before the nuclear and chemical stress tests; exceptions may be made for people with diabetes. Patients should also delay taking their morning medications before the test. It’s also important to wear comfortable walking shoes for an exercise cardiac stress test.

The patient’s heart rate and blood pressure are checked before the test, and he or she wears a heart monitor throughout the test. The physician checks the patient’s EKG and blood pressure at regular intervals during the test.

At McCullough-Hyde, a registered nurse with special coronary and critical care training assists the physician with all stress tests. The internal medicine physician is present to monitor and interpret the test, and if a heart scan is done, a radiologist will interpret it.

The thought of a cardiac stress test can be scary, but knowing that you will be surrounded by a well-trained, caring team at McCullough-Hyde Memorial Hospital will make the experience less frightening.