Cardiovascular nuclear medicine: a new look at an old problem. Noninvasive approaches to the evaluation of coronary heart disease: new horizons for radiologists lecture.

Radioactive tracers were first used to investigate cardiovascular physiology in 1927. Since that time, many procedures have been developed to measure perfusion to the myocardium and the function of the heart. The site and extent of both fixed and transient changes in regional perfusion can be detected noninvasively with monovalent cationic tracers. In addition, both the total function of the heart, such as cardiac output, and ejection fraction of both ventricles and the regional function such as wall motion measurements can be readily performed following intravenous administration of tracers. These tests are useful in evaluating patients with suspected or proved coronary artery disease.