What is the role of antiplatelet therapy after CABG, and when is aspirin typically resumed?

• A. Antiplatelet therapy is not used
• B. Aspirin is resumed within 6-24 hours postoperatively once hemostasis is secured
• C. Aspirin starts before surgery only
• D. Do not resume aspirin after CABG

Answer: (B)

Aspirin after CABG is used to keep the grafts open by preventing clot formation on the new conduits. It works by irreversibly inhibiting COX-1 in platelets, which lowers thromboxane A2 and reduces platelet aggregation, helping maintain graft patency.

Because the risk of early graft thrombosis is highest soon after surgery, aspirin is started early once surgical bleeding is controlled. The typical approach is a low dose, such as 75–100 mg daily, resumed within 6–24 hours after surgery when hemostasis has been secured, and then continued long-term unless there are contraindications.

If there’s significant postoperative bleeding or other bleeding risks, timing may be adjusted, but the goal remains to restart aspirin as soon as it’s safely possible to protect graft patency.