NUCLEAR STRESS TESTING
Diagnostic Testing & Imaging
What is nuclear stress testing?
A nuclear stress test (also called myocardial perfusion imaging) is a specialized type of test in cardiology that is helpful when other tests (exercise stress test or cardiac catheterization) either cannot be performed or do not give conclusive answers. It combines aspects of a stress test (where exercise or a medication is used to increase your heart rate) and nuclear imaging (where radioactive tracers are caught by a gamma camera) to provide highly accurate information about how your heart works at rest and when working harder.
How is nuclear stress testing performed?
The first thing your doctor will want to do is see how your heart works at rest. To do this, ECG wires will be connected to your chest, arms, and legs to help tell the camera when to take a picture. A small amount of the radiotracer will be injected into your blood through an IV line, and the special camera will take pictures over the next 10-30 minutes as you lie still on a table. Afterward the doctor will want to get images when your heart is stressed, or working harder. You may be asked to exercise to get your heart rate up, but usually your doctor can do this artificially with a medication. The medication will be given through your IV line while your doctor watches your heart rate with the ECG. When your heart is appropriately stressed, more radiotracer will be given by the IV line, and the camera will again start taking pictures. By comparing the two sets of images - at rest and when your heart is stressed - your doctor can get valuable information about your heart muscle as it works. Overall, the entire process can take up to several hours.
Nuclear Stress Testing
What is nuclear stress testing used for?
The nuclear stress test is most beneficial for patients with stable chest pain that is concerning for coronary artery disease. Coronary artery disease is easiest to diagnose when the heart is stressed because the narrowed arteries cannot provide enough blood to the working heart muscle. As the nuclear stress test is performed, the specialized radiotracer moves from your blood to the heart muscle, and the special camera can see what parts of your heart, if any, are not getting enough blood. This information is helpful in evaluating your risk for a heart attack or to plan for definitive intervention to prevent a heart attack from even happening.
References
[1] Aboyans, V., Criqui, M. H., Abraham, P., Allison, M. A., Creager, M. A., Diehm, C., … Treat-Jacobson, D. (2012). Measurement and interpretation of the Ankle-Brachial Index: A scientific statement from the American Heart Association. Circulation, 126(24), 2890–2909.