What is a MuGA scan?
A MuGA scan is a test that shows how your heart is pumping blood during rest, exercise, or both. During a MuGA scan, a radioactive substance is injected into your bloodstream. The substance is safe and will not harm you.

The radioactive substance "tags", or attaches to, the red blood cells in your blood. A special camera that picks up gamma rays is used to take pictures of your heart as the "tagged" red blood cells circulate.

A MuGA scan may be called by other names, such as Gated Blood Pool Scan, multigated acquisition, Cardiac Blood Pool Scan, Ejection Fraction Study, Radionuclide Angiography, Radionuclide Ventriculogram, and Wall Motion Study

What information will it give my doctors? Why is it requested?
The test can tell your doctors how well your heart is pumping blood. It can help determine how hard your heart is working. It is used to determine the “ejection fraction” or percentage of the blood that is pumped out of your heart's lower chambers (called the ventricles) with each heartbeat.

It may be requested to evaluate the effect of coronary heart disease, heart failure, cardiomyopathies, or heart function in general. It may also be used to evaluate heart function before giving drugs which may cause heart damage, and then repeated at intervals to check for any heart damage from these drugs.

What should my doctor know before I have this scan done?
If you think you might be pregnant, talk to your doctor before you schedule this test.

Where is the MuGA scan done?
MuGA scans are done in Nuclear Cardiology, in the Duke Clinic Radiology Department.

How do I prepare for a MuGA scan?
For a resting MuGA scan, no special preparation is needed.

For a stress -- or exercise -- MuGA, do not eat or drink anything other than water after midnight the night before the test. Ask your doctor about taking any medications you may be on. If you are taking any heart medications bring the medicine with you.

Do I need to have someone drive me home afterward?
No.

What happens during the MuGA scan?
A technologist will clean certain areas on your chest so that he or she can place small metal disks called electrodes on those areas. The electrodes have wires called leads, which are attached to a nuclear imaging computer. Then the technologist will give you two injections: the first injection prepares the red blood cells, and the second is used to "tag" the red blood cells.

The technologist will ask you to lie down on a small examination table, which has a special camera around it. Then, the technologist will take a number of pictures of your heart with the gamma-ray camera. If your doctor ordered only a resting MuGA scan, this would be the end of the test.

If your doctor ordered an exercise MuGAscan, you will be moved to a different examination table. When you lie down, there will be pedals at the end of the bed. You will put your feet in the pedals and, while still lying down, begin to pedal as if you were riding a bicycle. Using the gamma-ray camera, the technician will take a number of pictures of your heart. Your doctor may also be present to look at the pictures of your heart during the test.

The test can be stopped at any time that you feel fatigued or experience discomfort. If you feel chest pain, tell the technologist.  The whole procedure generally takes one-and-a-half to two hours.

What happens after the MuGA scan?
After the test, if you exercised you may feel tired. If you have had an exercise MuGA, someone will stay with you and monitor you until your blood pressure and pulse return to normal. You will be allowed to resume your normal activities as soon as you are done with the test and monitoring. The harmless radioactive substance will leave your body within one or two days.

What are the risks associated with this test?
On rare occasions, problems may arise as a result of the exercise. Staff experienced in treating cardiac problems will be available during the test.

When should I call the doctor?
If you have coronary artery disease and develop chest pain after returning home, contact your cardiologist.

How will I get the results of this test?
Your doctor will discuss the results of the MuGA Scan with you. The technologist will make calculation based on the computer images. These are given to the radiologist to interpret. The radiologist's interpretation will be available to your doctor the same day of the study.

This article is intended as a resource for patients receiving their cancer care at Duke University Hospital or Duke Clinic. It is not intended to substitute for medical advice from your health care team. If your doctor’s instructions differ from the information in this article, please talk with your doctor before making any changes.

Source: Duke Cancer Patient Education Program / Patient & Family Education Committee 8/00