Cardiomyopathies: Evaluation with radionuclide techniques

Abstract

In recent years radioactive tracers have been used more extensively in the care of patients with coronary artery disease (CAD), valvular lesions, intracardiac shunts and cardiomyopathies. Radionuclide techniques have achieved a role in cardiology equal in importance to electrocardiography, echocardiography and cardiac catheterization. Several factors have contributed to the progress in nuclear cardiology. The fIrst is the development of gamma scintillation cameras with better spatial resolution. The second is the availability of medically suitable radiopharmaceuticals which will selectively in the normal or injured myocardium. The third involves minicomputers and microprocessors which are nowadays fast, powerful and compact and allow the processing and storing of large volumes of data at a relatively low cost. Fourth, since radionuclide studies are noninvasive, they can easily be repeated and interventions can be studies at short term. At last, radionuclide studies provide information of cardiac function which can not be given with other diagnostic techniques. For example, recent research with cyclotron-produced radioisotopes, such as free fatty acids (FFA) labeled with carbon-11 or iodine-123, indicates that is possible to study regional myocardial metabolism and to differentiate diseases characterized by a decreased supply of blood from those characterized by an increased demand of substrate. Not only in CAD, but also in idiopathic cardiomyopathy, such studies may be valuable to improve out understanding of disease processes.