In PET Positron Emission Tomography (PET) Positron emission tomography (PET) is a type of medical imaging called radionuclide scanning. By detecting radiation after a radioactive material is administered, PET creates images that can... read more , 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, usually combined with computed tomography Computed Tomography (CT) of the Heart Computed tomography (CT) is a type of medical imaging that combines a series of x-rays to create cross-sectional, detailed images of internal structures, including the heart. CT may be used... read more (PET-CT), 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. CT generates cross-sectional slices of these areas and then combines them to produce detailed three-dimensional images.
PET-CT scans produce clearer images than do other radionuclide procedures Radionuclide Imaging of the Heart Radionuclide imaging is a type of medical imaging that produces images by detecting radiation after a radioactive material is administered by vein. Radionuclide imaging of the heart can be helpful... read more and can be used for stress testing Stress Testing Stress testing measures the heart's function with electrocardiography (ECG) while the heart is under stress, either from exercise or from a medication used to stress the heart. Stressing the... read more . However, the procedure is expensive and not as widely available as single-photon emission computed tomography. It is used in research and in cases in which simpler, less expensive procedures are inconclusive.