The purpose of this study is to demonstrate the superiority of a strategy of platelet monitoring (Monitoring Arm) with down-adjustment of the dose of prasugrel in high responders and up-adjustment of the dose of prasugrel in low responders as compared to a more conventional strategy of a fixed dose of 5 mg to every patient without monitoring (Conventional Arm) as measured by a reduction in the composite endpoint of, cardiovascular (CV) death, myocardial infarction (MI) , stroke, stent thrombosis (ARC definition type "definite"), urgent revascularisation or bleeding (BARC definition type 2, 3 or 5).