Not all patients with cardiovascular disease (CVD) benefit from long-term aspirin therapy. More importantly, recent evidence indicates that patients who are identified as “aspirin resistant” are at a more than fourfold increased risk of having an adverse cardiovascular event.1^–3 These increased risks are seen in patients with different cardiovascular problems who have been classified as aspirin resistant, using a variety of measurements of aspirin resistance. While there are many purported explanations for this—for example, non-compliance, too low an aspirin dose, etc,4 5 it is difficult to refute the evidence that there are numerous platelet function assays, all of which indicate that not all patients’ platelets are dysfunctional after aspirin ingestion—that is, they are aspirin resistant.1^–3 6^–10 Moreover, the increased risks in these patients are higher than in those patients in whom aspirin yields the expected response, regardless of which test is used.1^–3 These increased risks are seen in a wide variety of patient populations with cardiovascular or cerebrovascular disease—that is, in patients with stable CVD, CAD, after percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG), in patients undergoing other vascular procedures and in patients after a stroke.2 However, there is still …