Cardiac Positron Emission Tomography (PET)


What is a cardiac PET study?

A PET study is a test used to check blood flow to your heart. During the test, a small amount of radioactive tracer is injected into a vein. The tracer is not a dye or contrast. A special camera, called a PET scanner, detects the radiation released by the tracer and creates computer images of your heart. The test is combined with a medication to open your blood vessels (vasodilator). The medication simulates the effects of exercise on your cardiovascular system, and is used if you are unable to exercise on a treadmill or stationary bike. The test plus the medication helps your doctor know if your heart is getting enough blood while you are active compared to when you are resting.

The test is also used to:

  • Find out how much heart damage you have after a heart attack
  • Find out how well your cardiac treatment plan is working

Test Details

Can I eat or drink on the day of the test?

  • DO NOT eat or drink anything except water for 4 hours before the test.
  • DO NOT have anything that contains caffeine for 24 hours before the test. This includes coffee, tea, cola and other sodas, chocolate and strawberries (these contain a small amount of caffeine). It also includes products labeled decaffeinated and caffeine-free (these contain small amounts of caffeine). Caffeine affects the test results.
  • DO NOT SMOKE ON THE DAY OF THE TEST; nicotine affects the test results.

Should I take my medications the day of the test?

Please bring a list of all medications and supplements you take, including those that are non-prescription (over-the-counter

Medications with caffeine: DO NOT take any over-the-counter medication that contains caffeine (such as Excedrin®, Anacin®, diet pills and NoDoz®) for 24 hours before the test. Talk to your doctor, pharmacist or nurse if you have questions about other medications that may contain caffeine.

If you have asthma: DO NOT take theophylline (Theo-dur) for 48 hours before the test. Please bring your asthma inhaler to the test.

If you have diabetes: If you take insulin, ask your doctor how much you should take the day of the test. You may need to take half of your usual morning dose and eat a light meal 4 hours before the test. If you take pills to manage your blood sugar, do not take your medication before the test. Bring your diabetes medication with you so you can take it after you finish the test. 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 test. If you think your blood sugar is low, tell us right away. Plan to eat and take your medication after the test.

If you take heart medications: Ask your doctor about changes you need to make to your medications before the test. DO NOT stop taking any medication unless your doctor tells you to. You should only take these medications on the day of the test if you have chest pain:

  • Isosorbide dinitrate (Dilatrate®, Isordil®)
  • Isosorbide mononitrate (Imdur®, ISMO®, Monoket®)
  • Nitroglycerin (Minitran®, Nitropatches®, Nitrostat®)
  • Dipyridamole (Persantine®) -- Stop taking 48 hours before the test

What to expect during the test

  • Your test will take place in Nuclear Medicine located at JB-3 (in the basement of the Miller Family Pavilion). The testing area is supervised by a doctor.
  • You will remove clothing from the waist up and wear a hospital gown during the test.
  • You will have an EKG before and during the test to keep track of your heart’s electrical activity. Several small, sticky patches (electrodes) will be placed on your body to record the EKG. We will also check your blood pressure before the test.
  • You will get an IV in your arm or hand. The IV is used to give you medication and the tracer during the test.
  • You will lie still on the exam table. A camera will be over you.
  • You will get a small amount of radioactive tracer, through your IV so your doctor can check your blood flow while you are resting. It will be about 20 minutes before the first set of images are taken
  • You will get medication (vasodilator) through your IV to cause your heart to react as if you were exercising. You may feel warm or flush and may have a mild headache.
  • You will get another small amount of tracer so your doctor can check your blood flow while you re active. Your doctor will compare the two scans (resting and active).
  • Your healthcare team will ask you how you are feeling several times during the test. Please tell them if you have any pain or discomfort in your chest, arm or jaw, or if you feel short of breath, dizzy, lightheaded, or have any other unusual symptoms.
  • The IV will be removed from your arm at the end of the test.

How long will the test last?

The appointment will take approximately 1-2 hours.

Results and Follow-Up

How do I get the results of my test?

A cardiologist will review your test, and the results will go into your electronic medical record. Your referring doctor will have access to the results and will contact you to discuss them.

This information is about testing and procedures and may include instructions specific to Cleveland Clinic. Please consult your physician for information pertaining to your testing.

Last reviewed by a Cleveland Clinic medical professional on 05/03/2019.

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