This randomized controlled trial aims to evaluate the safety and efficacy of an aspirin-free strategy after 3-6 months of dual antiplatelet therapy (DAPT) in patients with acute coronary syndrome (ACS) who have undergone complete coronary revascularization by percutaneous coronary intervention (PCI). Participants will be randomized to either discontinue aspirin and continue P2Y12 inhibitor monotherapy or continue standard antiplatelet therapy. The primary objective is to determine whether the aspirin-free strategy reduces bleeding events without increasing ischemic events during follow-up.