In 167 patients with suspected coronary artery disease, 74 of whom had myocardial infarction (MI), measurement of myocardial fractional flow reserve (FFR) in previous infarction territories, using a cut-off point of 0.75, showed a sensitivity of 79% and a specificity of 79% for myocardial ischemia as demonstrated by thallium-201 myocardial imaging. This sensitivity and specificity were similar to a sensitivity of 79% and a specificity of 72% observed in territories not related to MI. In addition, a receiver-operating characteristic curve analysis revealed that the best predictability of FFR for myocardial ischemia was between 0.74 and 0.76, regardless of the presence or absence of MI.