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Cardiolite® Stress Test

What is it?

A Cardiolite® stress test takes pictures of your heart muscles and arteries (blood vessels). This test will be done while you exercise. Exercise makes your heart work harder. This test will show caregivers how your heart performs when it needs to work hard. This is a type of nuclear medicine scan that is also called cardiac imaging.

Why do I need a Cardiolite® stress test?

The test helps caregivers diagnose coronary artery disease. This is a condition where the blood vessels that give oxygen-rich blood to your heart muscles become narrow or blocked. The test helps caregivers find areas of heart muscle that do not get enough blood supply. The test can also show areas that have been damaged after a heart attack.

Who should not have this test?

Tell your caregiver before the test if you might be or are pregnant. Caregivers may suggest waiting to have the test until after your baby is born. Tell caregivers if you are breast feeding. They may suggest waiting to have the test until after you have finished breast feeding your baby. You may not be able to have this test if you have certain heart or health conditions. These conditions include bundle branch block, left ventricular hypertrophy, or low blood potassium.

What should I do to get ready for the Cardiolite® stress test?

  • Do not eat or drink anything except water for six hours before the test. Do not eat or drink anything with caffeine for 24 hours (one day) before the test. Caffeine may be found in some types of coffee, tea, soda, chocolate, sports drinks and foods.
  • Do not use any medicines (over-the-counter or prescribed) that contain caffeine for 24 hours (one day) before the test. These include Anacin®, Excedrin®, Darvon®, or Fiorinal®.
  • Do not smoke or use chewing tobacco for six hours before the test.
  • Wear or bring comfortable, loose-fitting clothes and walking shoes.
  • Bring a list of all medicines you are taking, or bring the pill bottles. Ask caregivers if you need to stop taking any of your usual medicines for a time before the test.
  • If you have diabetes and are taking insulin, ask caregivers if you need to change the amount of insulin that you are taking.
  • Tell your caregiver if you take any medicine that has xanthine (ZAN-theen) in it. Some of these medicines include theophylline (Slo-bid™, Theo-dur®) and pentoxifylline (Trental®). You may need to stop taking the medicine for several days before the test.
  • Stop taking sildenafil citrate (Viagra®) for 48 hours (two days) before this test. If you have chest pain during this test, you may be given medicine called nitroglycerin to treat it. This medicine can cause very low blood pressure in people who have recently taken Viagra®.

How is a Cardiolite® stress test performed?

  • When you arrive at the Nuclear Medicine department, you will need to change into comfortable clothes. A caregiver puts an IV (intravenous line) into a vein, usually in your hand or arm. Electrodes (patches) are placed on your chest. The electrodes record your electrocardiogram (ee-lek-troh-KAHR-dee-oh-gram) or "EKG". This is a test that records the activity of your heart.
  • You will start walking on a treadmill, or pedaling on a stationary bicycle. The speed and incline of the treadmill, or the resistance of the bicycle will increase every three minutes.
  • A tracer substance called Cardiolite® is put into the IV when your heart rate reaches a certain speed. The tracer moves through the blood and goes into heart muscle. Heart muscle that does not have enough blood supply takes in the Cardiolite® slowly, or not at all.
  • You will exercise about nine to 12 minutes. After that, you will rest for five to 10 minutes. During this time, caregivers will watch your EKG and blood pressure.
  • One hour after exercising, you will go to the radiology department. There you will have a scan taken. The scan takes about 30 minutes to do. The scan shows areas of narrow or blocked vessels, or areas of damaged heart muscle.
  • You may need another scan on a different day, while you are resting. For this test, you will not need to exercise on a treadmill or bicycle. Do not eat, drink, smoke, use tobacco, or take caffeine for six hours before this test is done.

What will I feel during the test?

You may feel discomfort when the IV is put in your vein. Tell caregivers if you have chest pain, feel short of breath, have very tired legs, or feel dizzy.

What do I have to do after the scan?

You may continue activities, eat, drink, and take your usual medicines as you did before the test. Drink plenty of fluids, such as water and juices to help flush the tracer out of your body. The tracer leaves your body quickly through your urine. Your caregiver may tell you to flush the toilet three times after going to the bathroom. This makes sure that the small amount of tracer leaving your body does not stay in the toilet bowl.


  • You may feel nauseated (sick to your stomach) or vomit (throw up) during or after this test. Rarely, a person might develop a rash, swelling, or have an allergic reaction to the medicine. The place where your IV is could bleed, become red, swollen, painful, or infected. There is a very small chance that you could become very short of breath during or after the test. You may get low blood pressure, have abnormal heartbeats, or have a heart attack. Caregivers will watch for and treat these problems. The radiation that is in the Cardiolite® is small and safe. The camera used for the scan does not take x-rays.
  • If you do not have a Cardiolite® stress test, caregivers may not be able to decide what would be the best care for your health condition. Your condition could get worse or you could die. Call your caregiver if you are worried or have questions about your medicine or care.

Care Agreement

You have the right to help plan your care. To help with this plan, you must learn about your health condition and how it may be treated. You can then discuss treatment options with your caregivers. Work with them to decide what care may be used to treat you. You always have the right to refuse treatment.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.