Heart Disease and Stress Tests
How Should I Prepare for the Exercise Stress Test?
Before your stress test:
- Do not eat or drink anything except water for four hours before the 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 (for example, Isordil, Dilatrate SR); Isosorbide mononitrate (for example, ISMO, Imdur, Monoket); Nitroglycerin (for example, Deponit, Nitrostat, Nitro-bid). Your doctor may also ask you to stop taking other heart drugs on the day of your test. If you have any questions about your medications, ask your doctor. Do not discontinue any drug without first talking with your doctor.
- If you use an inhaler for your breathing, bring it to the test.
What If I Have Diabetes?
If you have diabetes and are scheduled for a stress test:
- If you take insulin to control your blood sugar, ask your doctor what amount of your medication you should take the day of the test. Often, you will take only half of your usual morning dose and eat a light meal four hours before the test.
- If you take pills to control your blood sugar, do not take your medication until after the test is complete.
- Do not take your diabetes medication and skip a meal before the test.
- If you own a glucose monitor, bring it with you to check your blood sugar levels before and after your exercise stress test. If you think that your blood sugar is low, tell the lab personnel immediately.
- Plan to eat and take your blood sugar medication following your stress test.
What Should I Wear the Day of the Stress Test?
On the day of your stress test, wear soft-soled shoes suitable for walking and comfortable clothes. Do not bring valuables.
What Happens During the Exercise Stress Test?
First, during a stress test, a technician will gently clean 10 small areas on your chest and place electrodes (small, flat, sticky patches) on these areas. The electrodes are attached to an electrocardiograph monitor (ECG or EKG) that charts your heart's electrical activity during the test.
Before you start exercising, the technician will perform an ECG to measure your heart rate at rest and will take your blood pressure.
You will begin to exercise by walking on a treadmill or pedaling a stationary bicycle. The rate of exercise or degree of difficulty will gradually increase. You will be asked to exercise until you feel exhausted.
At regular intervals, the lab personnel will ask how you are feeling. Please tell them if you feel chest, arm, or jaw pain or discomfort, short of breath, dizzy, lightheaded, or any other unusual symptoms. It is normal for your heart rate, blood pressure, breathing rate, and perspiration to increase during the test. The lab personnel will watch for any symptoms or changes on the ECG monitor that suggest the test should be stopped.