Cardiac receptor physiology and imaging: An update

Understanding cardiac receptor physiology is crucial to the study of cardiovascular diseases. The availability of noninvasive imaging technology in studying cardiac receptors has greatly expanded our knowledge of their roles in the pathogenesis of several cardiac disorders such as ischemia and heart failure. The dynamic nature imaging "physiology" rather than anatomy often requires precise imaging protocols and complex mathematical modeling. The use of radiolabeled ligands adds the additional complications of radiation safety and radiopharmaceutical synthesis. Successful utilization of this technology must involve collaborative efforts of cardiologists, radiologists, radiochemists, physicists, mathematicians, technologists, and of course, referring physicians. Cardiac receptor imaging offers, in return, only tremendous opportunities for scientific discovery in physiology and pathophysiology, but also opportunities for clinical decision making. Imaging is a powerful tool for following the patients' responses to therapy and for predicting prognosis and dictating treatment. Much more effort is still needed to develop radiopharmaceutical agents for the various receptors and parts of receptor systems that cannot be imaged currently. More research needs to be done to expand this technology for wider clinical application.