Aspirin has a steadfast role in the short-term treatment and prevention of recurrence of ASCVD, though its role in long-term secondary prevention ≥ 1 year may change with excess bleeding compared to P2Y12 inhibitors, as well as when used in combination with anticoagulants for other indications such as atrial fibrillation. This evidence concerns the gene P2RY12 and atrial fibrillation.