[Aspirin in patients undergoing percutaneous coronary intervention]

Prophylactic use of aspirin at doses between 75 to 162 mg/d is a class I indication for all patients with stable coronary artery disease unless there is a contraindication. However, some studies suggest that long-term treatment with low dose aspirin is associated with a progressive reduction in platelet sensitivity to this drug. Given that percutaneous coronary stent implantation causes vascular injury with a subsequent activation of platelets and proinflammatory cytokines, some investigators suggest that higher aspirin doses should be considered for patients undergoing stent implantation. However, randomized clinical studies failed to show any benefit of additional high dose aspirin on top of standard low dose regimen before elective stent implantation. On the other hand, for those treated with drug-eluting stents aspirin is recommended at relatively higher doses (325 mg/d) started before the procedure and continue for up to 6 months after the intervention. Although, 325 mg/d is the dose preferred in clinical trials one may argue that lower doses can be as effective. Indeed, subgroup analysis of CURE trial demonstrated that aspirin at doses >100 mg/d increases bleeding complications without any additional reduction in cardiovascular events. In summary, although aspirin is recommended for every patient with coronary artery disease, its optimal dose for patients who underwent stent implantation is still not clear.