Nuclear stress test
Published April 17, 2024 | 
(1997)
A nuclear stress test involves taking images of the heart after injecting a small amount of a radioactive substance (radionuclide) such as thallium or sestamibi into a vein during monitored physical exercise. The images are made with a special camera that can detect the very low level of energy (radiation) given off by the material as it passes through the heart or localizes in the heart muscle. Such a test can give useful information about the size of the chambers of the heart, the pumping action of the ventricles and vital information about the blood supply to the heart muscle.
Nuclear scanning of the heart may provide more detailed information than a simpler and much less expensive exercise electrocardiogram. Because of the special equipment that the scan requires and the expense, such testing is reserved for people whose problems can’t be resolved by simpler and less costly examination. In people who are unable to exercise, nuclear testing can be done after administration of medications that can mimic the effects of physical stress on the heart. Lastly, the scans do not provide detailed information about blockages of the coronary arteries, which are best seen using an injection of dye into the arteries (angiogram).