In STEMI patients undergoing PPCI there is a delayed onset of action of oral P2Y12 receptor inhibitors, including prasugrel and ticagrelor. Crushing prasugrel and ticagrelor improves their PK and PD profiles as it favors drug absorption and onset of antiplatelet effects and because of this, it is commonly used in STEMI patients undergoing PPCI. However, despite the use of crushed tablets, up to one-third of patients may still have high on-treatment platelet reactivity (HPR) within the first 2 hours after loading dose (LD) administration of these oral agents. Cangrelor is a potent intravenous P2Y12 receptor inhibitor with rapid onset and offset of action associated with a greater reduction in ischemic events compared with clopidogrel in P2Y12 receptor naïve patients undergoing PCI. To date most studies have explored cangrelor in the setting of PCI subjects treated with clopidogrel. The PD effects of cangrelor in STEMI patients undergoing PPCI treated with a newer generation P2Y12 receptor inhibitor and how this compares with a crushed formulation of the oral drug is unexplored. The aim of this prospective randomized study is to investigate the PD effects of cangrelor in STEMI patients undergoing PPCI treated with crushed ticagrelor.