What is a radionuclide ventriculogram?

A radionuclide ventriculogram (RVG) uses a radioactive chemical injected into your vein to show how well your heart is pumping. It measures the amount and flow of blood that is pumped with each heartbeat. An RVG also gives information about the size of the chambers of the heart and the strength of the heart muscle. It is also called a MUGA (multigated acquisition) scan.

The heart has 4 sections, or chambers. The upper chambers are each called atria, and the lower chambers are called ventricles. Blood flows from the right atrium into the right ventricle, and the right ventricle pumps it to the lungs. As it passes through the lungs, the blood picks up oxygen and leaves behind carbon dioxide. Then the blood flows back to the heart and into the left atrium, and from there into the left ventricle. The left ventricle pumps the blood out to the rest of the body, with a small amount going to the heart muscle itself.

When is it used?

An RVG can detect early changes in your heart that might be missed by other tests. It may be used to check how well the heart is pumping if you have:

• Heart problems that your child was born with
• Cancer chemotherapy
• Lung problems that affect the heart
• Cardiomyopathy, which is a problem with the heart muscle

How do I prepare for this procedure?

• You may or may not need to take your regular medicines the day of the procedure. Tell your healthcare provider about all medicines and supplements that you take. Some products may increase your risk of side effects. Ask your healthcare provider if you need to avoid taking any medicine or supplements before the procedure.
• Tell your healthcare provider if you have any food, medicine, or other allergies such as latex. Tell your provider if you have had kidney problems or an allergy to chemicals, such as contrast dye. Contrast dye is used for some scans.
• Your healthcare provider will tell you when to stop eating and drinking before the procedure. This helps to keep you from vomiting during the procedure.
• Follow your provider’s instructions about not smoking before and after the procedure. Smokers may have more breathing problems during the procedure and heal more slowly. It’s best to quit 6 to 8 weeks before surgery.
• Follow any other instructions your healthcare provider gives you.
• Ask any questions you have before the procedure. You should understand what your healthcare provider is going to do. You have the right to make decisions about your healthcare and to give permission for any tests or procedures.

What happens during the procedure?

An ECG (also called an EKG or electrocardiogram) to measure and record your heartbeat is done at the same time. For an ECG, small sticky pads are put on your chest, arms, and legs. Long wires will be attached to the pads and connected to a recording machine.

For the RVG, you will lie down on a table. A radioactive chemical is injected into your vein. The level of radiation is about the same as the amount you get during a chest X-ray. The radioactive chemical goes through your bloodstream to your heart. A camera that shows the radioactive chemical takes several pictures during each heartbeat while you are resting. You may also have an RVG while you exercise on a treadmill or pedal a stationary bicycle.

What happens after the procedure?

After the test, you can go home and go back to your normal activities. Any skin irritation from the ECG pads will go away quickly after they are removed.

Ask your healthcare provider:

• How and when you will hear your test results
• What symptoms or problems you should watch for and what to do if you have them

Make sure you know when you should come back for a checkup. Keep all appointments for provider visits or tests.

What are the risks of this procedure?

Every procedure or treatment has risks. Some possible risks of this procedure include:

• You may have a reaction to the radioactive chemical.
• You may have an abnormal heart rhythm during the test.

Ask your healthcare provider how these risks apply to you. Be sure to discuss any other questions or concerns that you may have.