Nuclear Stress Testing

One way that a physician diagnoses coronary heart disease is through a nuclear stress test. During a nuclear stress test, a small dose of a radioactive isotope is injected into the bloodstream. The radioisotope, or tracer, is carried through the bloodstream and into the myocardium, or heart muscle. Shortly after exercising, a special camera senses the radioactivity of the tracer and constructs an image of the heart. Parts of the heart muscle that receive normal blood flow receive larger amounts of tracer and appear brighter than areas that have inadequate blood flow.