Cardiac Stress Test Patient Services

What To Expect Before Stress Testing

Be sure to wear athletic or other shoes in which you can exercise comfortably. You may be asked to wear comfortable clothes in which you can easily exercise, or you may be given a gown to wear during the test.

Your doctor may ask you not to eat or drink anything but water for a short time before the test. If you’re diabetic, ask your doctor whether you need to adjust your medicines on the day of your test.

For some stress tests, you can’t drink coffee or other caffeinated drinks for a day before the test. Certain over-the-counter or prescribed medicines also may interfere with some stress tests. Ask your doctor whether you can take all your medicines as usual and whether you need to avoid certain drinks or foods.

If you use an inhaler for asthma or other breathing problems, bring it to the test and be sure to let the doctor know that you use it.


What To Expect During Stress Testing

During all types of stress testing, a technician will always be with you to closely monitor your health status.

Before you start the “stress” part of a stress test, a technician will put small sticky patches called electrodes on the skin of your chest, arms, and legs. To help an electrode stick to the skin, the technician may have to shave a patch of hair where the electrode will be attached.

The electrodes are connected to a machine that records the electrical activity of your heart. This recording, which is called an EKG (electrocardiogram), shows how fast your heart is beating and the heart’s rhythm (steady or irregular). The machine also records the strength and timing of electrical signals as they pass through each part of your heart.

The technician will put a blood pressure cuff on your arm to monitor your blood pressure during the stress test. (The cuff will feel tight on your arm when it expands every few minutes.) In addition, you may be asked to breathe into a special tube so the gases you breathe out can be monitored.

After these preparations, you will exercise on a treadmill or stationary bicycle. If such exercise poses a problem for you, you may instead turn a crank with your arms. During the test, the exercise level will get harder. But you can stop whenever you feel the exercise is too much for you.

The illustration shows a patient having a stress test. Electrodes are attached to the patient’s chest and connected to an EKG (electrocardiogram) machine. The EKG records the heart’s electrical activity. A blood pressure cuff is used to record the patient’s blood pressure while he walks on a


If you can’t exercise, a technician will inject a medicine into a vein in your arm or hand. This medicine will increase the flow of blood through the coronary arteries and/or make your heart beat faster, as would exercise. This results in your heart working harder, so the stress test can be performed. The medicine may make you flushed and anxious, but the effects disappear as soon as the test is over. The medicine may also give you a headache.

While you’re exercising or receiving medicine to make your heart work harder, the technician will ask you frequently how you’re feeling. You should tell him or her if you feel chest pain, shortness of breath, or dizzy. The exercise or medicine infusion will continue until you reach a target heart rate, or until you:

  • Feel moderate to severe chest pain
  • Get too out of breath to continue
  • Develop abnormally high or low blood pressure or an arrhythmia (an abnormal heartbeat)
  • Become dizzy

The technician will continue to monitor your heart functions and blood pressure for a short time after you stop exercising or stop receiving the stress-creating medicine. The “stress” part of a stress test (when you’re exercising or given a medicine that makes your heart work hard) usually lasts only about 15 minutes or less. But there is preparation time before the test and monitoring time afterward. Both extend the total test time to about an hour for a standard stress test, and up to 3 hours or more for some imaging stress tests.


What Does Stress Testing Show?

Stress testing provides your doctor with information about how your heart works during physical stress (exercise) and how healthy your heart is. Standard exercise stress testing uses an EKG (electrocardiogram) to monitor changes in the electrical activity of your heart. Imaging stress tests take pictures of the blood flow to different parts of your heart.

Both types of stress testing are used to look for signs that your heart isn’t getting enough blood flow during exercise. Abnormal results on stress testing may be due to coronary artery disease (CAD), but also can be due to other factors such as a lack of physical fitness.

If you have a standard exercise stress test and the results are normal, no further testing or treatment may be needed. But if your standard exercise stress test results are abnormal, or if you’re physically unable to exercise, your doctor may want you to have an imaging stress test or undergo other testing. Even if your standard exercise stress test results are normal, your doctor may want you to have an imaging stress test if you continue having symptoms (such as shortness of breath or chest pain).

Standard exercise stress testing isn’t equally accurate in men and women. Normal results from a standard exercise stress test usually accurately rule out CAD in both men and women. But a standard exercise stress test can show abnormal results even when the patient doesn’t have CAD (these results are called false positives). False positive exercise stress tests happen more often in women than in men.

Imaging stress tests are more accurate than standard exercise stress tests (in men and women) because they directly show how well blood is flowing in heart muscle and reveal parts of the heart that aren’t contracting strongly. But imaging stress tests are much more expensive than standard exercise stress tests.

Imaging stress tests can show the parts of the heart not getting enough blood, as well as dead tissue in the heart, where no blood flows. (A heart attack can cause some tissue in the heart to die.) If your imaging stress test suggests significant CAD, your doctor may want you to have more testing and/or treatment.

What Are the Risks of Stress Testing?

There’s little risk of being seriously harmed from any type of stress testing. The chance of these tests causing a heart attack or death is about 1 in 5,000. More common but less serious side effects linked to stress testing include:

  • Arrhythmia (an irregular heartbeat). This often will go away quickly once you’re at rest. But if it persists, you may need to go to the hospital and be monitored or get treatment.
  • Low blood pressure, which can cause you to feel dizzy or faint. This will go away once your heart stops working hard; it doesn’t usually require treatment.
  • Jitteriness or discomfort while getting medicine to make your heart work harder (you will be given medicine if you can’t exercise). These side effects usually disappear shortly after you stop getting the medicine, but in some cases may last a few hours.


A  Certified Internal Medicine Physician with Specialized Cardiac Training will review your results before you leave.  Then your exam is reviewed and interpreted by a board certified Cardiologists for the final detailed written report sent to your physician. Once your Physician has received and reviewed your results, they will call you to discuss the results with you. Urgent results will be telephoned immediately to your doctor.