European Society of Cardiology Guide give precise indications (but often ignored) on the use of PCI or coronary artery bypass grafting according to the extent of coronary artery disease and the site of injury . However, especially in patients with NSTE-ACS often we limit ourselves to dilate the culprit stenosis, leaving untreated other injuries that underlie large myocardial territory, that is, by configuring an incomplete revascularization framework. The calculation of the SYNTAX score residual (that is, what remains after percutaneous revascularization procedure) allows to objectively verify the incompleteness of PCI treatment, which correlates with the outcome in the patient's distance . Moreover, in case of equivocal stenosis, especially in patients with stable coronary disease, large should be the use of a functional assessment using the calculation of the Fractional Flow Reserve (FFR).