What is an Exercise Stress Test?
Patients with coronary artery blockages may have minimal symptoms and an unremarkable or unchanged EKG while at rest. However, symptoms and signs of heart disease may become unmasked by exposing the heart to the stress of exercise. During exercise, healthy coronary arteries naturally dilate. An artery that has a blockage does not dilate as much as health coronary arteries. This unequal dilation causes more blood to be delivered to heart muscle supplied by the normal artery. In contrast, narrowed arteries end up supplying reduced flow to it’s area of distribution. This reduced flow causes the involved muscle to “starve” fo oxygen during exercise. The oxygen “starvation” may produce symptoms like chest discomfort or inappropriate shortness of breath. In addition, EKG may produce characteristic abnormalities seen with myocardial ischemia.
Why Do I need a Stress Test?
- To determine if there is adequate blood flow to your heart during increasing levels of activity.
- To evaluate the effectiveness of your heart medications to control angina and ischemia.
- To determine the likelihood of having coronary artery disease and the need for further evaluation, espeically if you have risk factors for coronary artery disease.
- Check the effectiveness of procedures done to improve blood flow within the heart vessels in people with coronary heart disease.
- To evaluate exercise tolerance when patients have unexplained fatigue or shortness of breath
- Identify abnormal heart rhythm.
- Help you develop a safe exercise program.
How Do I Prepare for Exercise Stress Test?
- Do not eat or drink at least four hours prior to your stress test.
- Do not drink or eat foods containing caffeine for 12 hours before the test. Caffeine will interfere with the results of your test.
- Do not take the following heart medications on the day of your test unless your doctor tells you otherwise, or if the medication is needed to treat chest discomfort the day of the test: isosorbide dinitrate, isosorbide mononitrate, nitroglycerine, certain beta-blocking and calcium channel blocking medications.
- Do not take your diabetic pills until after the test is completed.
- If you take insulin for your diabetes, take half of your usual dose.
- Wear comfortable clothing and flat soled shoes for walking.