Nuclear ventriculography (MUGA or RNV)
RNV; Cardiac blood pooling imaging; Nuclear heart scan; Radionuclide ventriculography; MUGA
nuclear ventriculography (MUGA or RNV) is a test that uses radioactive tracers to make heart chambers and blood vessels visible. The procedure is non-invasive. The heart structures are not touched by instruments.
How the test is performed
A radioactive isotope is injected into your vein. Commonly used isotopes include technetium and thallium. Radioactive isotopes attach to red blood cells and pass through the heart in the circulating blood. The radioactive isotope can be traced through the heart using special cameras or scanners. The images may be synchronized with an electrocardiogram.
You will be tested when you are resting, then tested again with exercise or after administering certain medications.
How to prepare for the test
You may be required to abstain from food or beverages containing caffeine or alcohol for several hours before the test.
Infants and children:
The physical and psychological preparation you can provide for this or any test or procedure depends on your child’s age, interests, previous experiences, and level of trust. For specific information regarding how you can prepare your child, see the following topics as they correspond to your child’s age:
- Infant test or procedure preparation (birth to 1 year)
- Toddler test or procedure preparation (1 to 3 years)
- Preschooler test or procedure preparation (3 to 6 years)
- School age test or procedure preparation (6 to 12 years)
- Adolescent test or procedure preparation (12 to 18 years)
How the test will feel
Electrodes may be placed on your chest. An intravenous line will be placed in your arm to inject the radioactive isotope. A camera or scanner will be placed over the chest area to process the images. The scan may be repeated during exercise on a treadmill or stationary bicycle.
Why the test is performed
The test is performed when it is important to very accurately measure the pumping function of the heart.
Normal results indicate normal heart function, or a normal cardiac response to exercise.
What abnormal results mean
Abnormal results may indicate a myocardial infarction, coronary artery disease, heart valve disease, or other cardiac disorders.
Additional conditions under which the test may be performed:
- Atrial septal defect
- Dilated cardiomyopathy
- heart failure
- Idiopathic Cardiomyopathy
- Lyme disease, secondary
- Mitral stenosis
- Peripartum cardiomyopathy
- Senile cardiac amyloid
- SVC obstruction
What the risks are
Nuclear imaging tests carry a very low risk of complications. Exposure to radio tracers can be a concern for the nuclear lab staff, but not for patients undergoing an occasional nuclear imaging test.
by Potos A. Aagen, M.D.
All ArmMed Media material is provided for information only and is neither advice nor a substitute for proper medical care. Consult a qualified healthcare professional who understands your particular history for individual concerns.