This study is a prospective parallel assignment trial, the aim of which is to determine whether prescribing prasugrel or ticagrelor, rather than clopidogrel, after primary PCI in carriers of CYP2C19*2 LoF alleles is superior in reducing a net clinical benefit outcome consisting of cardiovascular death, myocardial infarction (MI), stent thrombosis, stroke and Platelet Inhibition and Patient Outcomes (PLATO) major bleeding. This evidence concerns the gene CYP2C19 and myocardial infarction.