A resting and exercise radionuclide angiogram (RNA) is a type of nuclear medicine test. This means that a tiny amount of a radioactive substance, called a tracer, is used to help show the tissue under study. In this test, doctors study the heart's chambers in motion. This test can tell the doctor how well the heart pumps and how much blood it pumps with each heartbeat (called the ejection fraction) both during exercise and at rest.
Your doctor injects a radioactive tracer (usually technetium) into an arm vein to "tag" blood cells so he or she can track their progress through the heart with a scanner. A special camera (called a gamma camera) then records the heart muscle at work, like a movie. Your doctor can match these recordings with the electrocardiogram (ECG), a recording of the heart's electrical activity.
An RNA test with rest and exercise is done so the doctor can assess the heart's function during exercise and compare it to how well the heart works at rest. If the heart muscle does not move in a normal way, or not enough blood is pumped out by the heart, it may be a sign of one or more of the following:
Reasons for your doctor to request a resting and exercise radionuclide angiogram (RNA) include:
If a screening exam (such as an electrocardiogram or ECG) suggests some type of heart disease that needs to be explored further, a resting and exercise RNA may be done.
There may be other reasons for your doctor to recommend resting and exercise RNA.
The amount of the radioactive tracer your doctor injects into your vein for the test is very small. So, there is no need for precautions against radiation exposure.
The injection of the radioactive tracer may cause some slight discomfort. Allergic reactions to the tracer are rare.
If you are pregnant or think you could be, tell your healthcare provider. There is risk of injury to the fetus from this test. Radiation exposure during pregnancy may lead to birth defects. If you are lactating, or breastfeeding, tell your healthcare provider due to the risk of contaminating breast milk with the radionuclide.
There may be other risks depending on your specific medical condition. Be sure to discuss any concerns with your doctor before the test.
Certain factors may interfere with or affect the results of this test. These include:
A resting and exercise radionuclide angiogram (RNA) may be done on an outpatient basis or as part of your stay in a hospital. Steps may vary depending on your condition and your doctor's practices.
Generally, a resting and exercise RNA follows this process:
Move slowly when getting up from the scanner table to avoid any dizziness or lightheadedness from lying flat for the length of the test.
Drink plenty of fluids and empty your bladder often for 24 to 48 hours after the test to help flush the remaining radioactive tracer from your body.
A nurse will check the IV site for any signs of redness or swelling. If you notice any pain, redness, or swelling at the IV site after you go home, tell your doctor as this may be a sign of infection or other type of reaction.
Your doctor may give you other instructions after the test, depending on your situation.
Before you agree to the test or the procedure make sure you know: