Myocardial Perfusion Imaging

Also known as: Rest-stress myocardial perfusion scan, myocardial perfusion scan, MPI test.

What is myocardial perfusion imaging?

Myocardial perfusion imaging, also called a nuclear cardiac stress test, helps determine the adequacy of blood flow to the heart. A radiopharmaceutical, a radioactive material, is injected through a vein and is taken up by the heart. The heart can then be imaged with a Gamma Camera. The camera is able to detect emissions from the radioactive material taken up by the heart muscle. Imaging is performed at rest and after exercise. Comparison of the stress and rest images helps detect inadequate blood flow to the heart to determine if there is ischemia or scarring.

Why am I having a myocardial perfusion scan?

Myocardial perfusion scan helps diagnose cardiac disease and is used to evaluate symptoms of unexplained chest pain or chest pain brought on by exercise, called angina. In congenital heart disease perfusion imaging also helps assess the impact of anatomical abnormalities.

Myocardial perfusion imaging:

  • Evaluates the presence and extent of suspected or known coronary artery disease.
  • Determines the extent of injury to the heart following a heart attack, or myocardial infarction.
  • Evaluates the results of bypass surgery or other revascularization procedures designed to restore blood supply to the heart.
  • Evaluates heart-wall movement and overall heart function with a technique called cardiac gating.

How long does the test take?

The exam is performed in 2 parts and will take 4-5 hours. A resting scan is performed in the morning following an injection of a radiopharmaceutical after an hour wait. A second stress scan is performed following exercise on a treadmill.

Can I have a reaction to the radiopharmaceutical?

The radiopharmaceutical is a radioactive material.  It is not a dye or iodine contrast and therefore an allergy or reaction is extremely rare.

What can I expect? 

After registering at patient access you will be directed to the nuclear department in radiology. First an IV will be placed in a peripheral vein. Then the radiopharmaceutical will be injected and a resting scan will be performed after a 60 minute wait. The exercise treadmill portion of the exam will take place in the cardiac stress lab and is performed by the on staff pediatric cardiologist. After a light lunch the final stress scan will be performed.

How Should I prepare for the test?

  • Have only a light early breakfast 3 hours before the test of a piece of toast or a piece of fruit.
  • You MAY drink some water or a few sips of juice prior to the test.
  • No coffee, tea, or cola or other caffeine containing products.
  • Ask your physician which medications you can take prior to the exam. Bring a list of your medications with you.
  • NO beta blockers or calcium channel blockers (unless otherwise instructed by your physician).
  • If you have asthma: Your physician will tell you NOT to take theophylline (Theo-Dur®) for 48 hours before the test. Please plan to bring your asthma inhaler to the test.
  • If you take heart medications: DO NOT take the following heart medications on the day of the test unless your physician tells you otherwise, or unless it is needed to treat chest discomfort the day of the test:
    • Isosorbide dinitrate (for example: Dilatrate®, Isordil®)
    • Isosorbide mononitrate (for example: Imdur®, ISMO®, Monoket®)
    • Nitroglycerin (for example: Minitran®, Nitropatches®, Nitrostat®)
    • Dipyridamole (Persantine®): Stop taking 48 hours before the test.
  • If you are diabetic please inform your doctor for special instructions.
  • Wear comfortable clothes and running shoes. Wear a comfortable two-piece outfit; avoid wearing dresses, jumpsuits or shirts with metallic buttons or zippers on the chest area. Avoid perfumes, lotions or oils on your chest area.

If you have further questions about the test please contact the nuclear medicine department at 305-666-6511 ext 8268.

Reviewed by: Rachel M Pevsner Crum, DO

This page was last updated on: January 07, 2022 10:04 AM

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