Multigated Acquisition Scan

What is a Multigated Acquisition Scan (MUGA)?

A multigated acquisition scan (MUGA) is a non-invasive and highly accurate test that evaluates the heart’s ability to pump. In a MUGA scan procedure, nuclear medicine is employed to help generate an image of the heart as it beats, as a tiny amount of radioactive substance is injected into the patient’s bloodstream. This substance attaches to red blood cells that move through the ventricles of the heart as blood circulates, and when viewed with a special camera, creates images of the heart pumping.

What is a MUGA scan used for and what does it show?

In addition to evaluating the heart’s pumping, a MUGA scan is used for determining abnormalities in the size of the ventricles and developing a picture of overall heart health. It can distinguish areas of heart muscle damage and provide information about potentially blocked arteries. A MUGA scan shows both blood flow through the heart and weakened areas of muscle that can limit heart function – and can help doctors treat patients who have experienced heart failure.

Reasons to run a MUGA scan:

  • Evaluate the heart’s pumping
  • Monitor heart ventricle size
  • Distinguish areas of weakened heart muscle
  • Gather information about potentially blocked arteries
  • Help assess and treat patients who have heart failure

MUGA scans can detect a number of conditions, such as congestive heart failure, cardiomyopathy and pulmonary hypertension. Symptoms of these conditions that may lead to your doctor ordering a MUGA heart scan include – but are not limited to – chest pain, difficulty breathing, dizziness and fatigue.

A MUGA procedure involves the use of Technetium 99. This is the radioactive substance that is injected into the patient’s bloodstream in a very restricted amount. The red blood cells that it attaches to then emit low levels of radiation that are detected by a gamma camera. This detection allows for the development of images of the heart as it beats, so the capacity for pumping can be evaluated.

MUGA Scan Preparation

To ensure the most comfortable experience, a patient’s MUGA scan preparation should include:

  • Not eating or drinking for 4-6 hours before the test
  • Abstaining from caffeine and tobacco for 24 hours before the test
  • Talking with the doctor about current medications and if they should be taken the day of the test
  • Informing the doctor of any allergies you may have, including barium
  • Alerting the doctor to any medical conditions
  • Notifying the doctor about recent nuclear tests
  • Informing your doctor if you may be pregnant

MUGA Side Effects

The MUGA scan risks and MUGA scan side effects are minimal. Because a tiny amount of radioactive substance is used to administer the test – less than what a patient is exposed to in an X-ray – the body processes it. In some cases, patients can have an allergic reaction to the substance.

MUGA Heart Scan Results

Typically, MUGA heart scan results will take a few days to receive. Results will be presented in a percentage and represent what is called the “left ventricle ejection fraction (LVEF)”. This determines if the heart is pumping blood into the body as it should be. A percentage between 50-70 is considered normal, and anything above or below this range could indicate a heart condition, and further treatment or surgery may be required.

MUGA Scan Procedures at Baptist Health

Patients experiencing chest pain, shortness of breath, dizziness or fatigue may need to schedule a MUGA scan procedure at Baptist Health. Those who have already experienced heart failure should also have a scan to identify areas of muscle damage and help determine potentially blocked arteries. For more information about a MUGA scan procedure, please contact your provider or the Baptist Health Imaging & Diagnostics team.