In clinical practice, indications might include high-risk patients who undergo PCI without proper pre-loading with an oral P2Y12-inhibitor (e.g., patients undergoing ad hoc high-risk PCI or STEMI patients presenting with resuscitated cardiac arrest) or opiate-treated STEMI patients in whom absorption of oral P2Y12 inhibitors is known to be delayed [33]. This evidence concerns the gene P2RY12 and cardiac arrest.