Test provides images of the heart throughout pumping cycle
A radionuclide angiogram (RNA) is an imaging test involving injection of radioactive tracer (radionuclide) that allows for clear images of the heart while it is pumping. The test is used to determine ejection fraction, which is how much blood is being pumped with each heartbeat, and it may be used to assess damage from a heart attack or from chemotherapy. A doctor may also recommend the test to determine reasons for symptoms such as chest pain, dizziness or fatigue.
An RNA is also referred to by different names, including multi-gated acquisition (MUGA) scan, gated blood pool single-photon emission computed tomography (SPECT) or just blood pool scan. The scan may be done at “rest” (lying on a table) or with “exercise/stress” (using a treadmill or stationary bike).
What to expect from MUGA scan
A MUGA scan is done on an outpatient basis. Your doctor may ask you to avoid any drinks with caffeine beforehand as drinking caffeinated beverages can affect your heart rhythm. If you are having an exercise stress test, you will be asked to avoid eating or drinking for four hours beforehand.
For the resting test, you will have electrodes (patches) attached to your chest, similar to an ECG. The electrodes are hooked up to a machine that records the electrical activity of the heart. Your own blood is drawn and mixed with a radioactive tracer then injected back into the bloodstream. The tracer highlights specific areas and a camera takes multiple images of the heart at different intervals throughout the pumping cycle.
After the MUGA scan you’ll be able to resume normal activities. Be sure to drink plenty of water to flush the radioactive tracer out of your body. Your doctor will review the results of your test and discuss any further testing or treatment options.