Myocardial reperfusion studies have provided a significant contribution in patients known to be carriers or with symptoms suggesting CAD; however, the use of functional tests in asymptomatic patients hv as not been defined with accuracy. In the light of the available epidemiological data in ischemic heart disease, in previously asymptomatic patients, the strategies and algorithms proposed should be reviewed to try to prevent major cardiac events in patients who were previously considered healthy. A proper use of radioisotope imaging may offer significant documentation and help in screening asymptomatic patients. The goal is to select subsets of asymptomatic patients in whom performing a functional myocardial perfusion SPECT test would be useful, and in turn to identify who between these patients would not benefit, having to undergo functional tests that has them even exposed to radiation unnecessarily.