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Positron Emission Tomography (PET) of the Heart


Michael J. Shea

, MD, Michigan Medicine at the University of Michigan;

Thomas Cascino

, MD, MSc, University of Michigan

Last full review/revision Oct 2019| Content last modified Oct 2019

In positron emission tomography (PET), a substance necessary for heart cell function (such as oxygen or sugar) is labeled with a radioactive substance (radionuclide) that gives off positrons (electrons with a positive charge). The labeled nutrient is injected into a vein and reaches the heart in a few minutes. A sensor detects the positrons and uses them to create a picture of the body part being studied.

PET is used to determine how much blood is reaching different parts of the heart muscle and how different parts of the heart muscle process (metabolize) various substances. For example, when labeled sugar is injected, doctors can determine which parts of the heart muscle have an inadequate blood supply because those parts use more sugar than normal.

PET scans produce clearer images than do other radionuclide procedures. However, the procedure is expensive and not widely available. It is used in research and in cases in which simpler, less expensive procedures are inconclusive.

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