How does a radionuclide angiogram work?

Advertisement
Advertisement
A radionuclide angiogram is a test used to gather images of the heart throughout its pumping cycle. You may also hear it referred to as a MUGA scan (multigated acquisition scan) or blood pool scan. The test can help assess how well your heart is pumping by measuring what is called the “ejection fraction,” the amount of blood that is pumped out of the heart’s two lower chambers (the ventricles). Generally, a healthy ejection fraction range is 50-70%. The test can be used to determine damage from a heart attack or chemotherapy, for example. A radionuclide angiogram may be performed at rest, or you may be asked to exercise to “stress” the heart.

For a radionuclide angiogram, a small amount of a radioactive tracer (technetium-99m) that emits gamma rays is injected into the bloodstream. The tracer “tags” red blood cells, making it possible to gather images of blood circulation in the heart. The gamma rays emitted by the tracer in the bloodstream are detected by a gamma camera. After the gamma rays are converted into an electrical signal, they go to a computer, which creates an image of the chambers of the heart.