Nuclear stress tests use a small amount of radioactive tracer, administered through an IV, to provide advanced images of the heart. A nuclear stress test might help your doctor diagnose a heart condition, such as a coronary artery blockage or poor heart pumping function. Your physician might order a nuclear stress test to determine if:
- Areas of your heart are damaged
- Your coronary arteries are blocked
- The blood flows normally through your heart
- The size and shape of your heart are normal
- To determine the differences between how your heart performs at rest and during exercise
What to expect during a nuclear stress test
Preparing for your procedure
Do not eat or drink anything for at least three hours prior to your nuclear stress test. Check with your physician to determine if any of your medications should be avoided for the days leading up to your scheduled test. Make sure to bring all of your medications, as well as any herbal or dietary supplements and over-the-counter medications, to the test with you. Your physician might instruct you to stop certain medicines before this test. Wear loose clothing and comfortable walking shoes.
During your procedure
A nuclear stress test can take up to four hours. First, a technician injects a small amount of radioactive tracer through an IV, and advanced scanning cameras take images that record whether this tracer shows up in your heart. Like other heart tests, electrodes are placed on your chest to monitor your heart’s electrical activity.
The pictures or images are fed into a computer, which reconstructs them as "slices" of a three dimensional heart. The technicians gather two sets of images: the first set provides information about how your heart performs at rest, and the second set provides information about how your heart performs with stress. Stress is accomplished as exercise stress, usually on a treadmill. If you are unable to exercise, a nurse will administer a drug to mimic the effect that exercise has on your heart. Prior to taking pictures of your heart, you may be asked to do light walking or drink water to help improve the quality of your heart pictures.
After your procedure
Your physician will provide detailed instructions on how to recover from a nuclear stress test. In general, you should get plenty of rest after your test is complete. A cardiologist will review the results of your test, and then your physician will contact you to discuss the results.
It is possible that the results from your nuclear stress test could lead to a change in the treatment of your heart condition or additional cardiac procedures. The test is also helpful in determining what kind of exercise program is safe for you.