In aortic dissection (AAD), S‐nitrosylated Septin2 in macrophages relieves TIAM1 inhibition, activating RAC1–NF‐κB to promote vascular inflammation. RAC1 inhibitors (NSC23766, R‐Ketorolac) attenuate AAD progression [198]. This evidence concerns the gene RAC1 and Aortic dissection.