Antiplatelet therapy has a prominent role in the treatment of a broad range of cardiovascular diseases, and data supporting the role of aspirin in secondary prevention are robust.1 As monotherapy, the thienopyridine clopidogrel has also been shown to have modestly superior efficacy compared with aspirin in secondary prevention for patients with recent myocardial infarction or stroke or with established peripheral arterial disease.2 When given in addition to aspirin, clopidogrel has been demonstrated to have an incremental benefit in patients with acute coronary syndromes, in those undergoing percutaneous coronary intervention (PCI), and most recently, in those who have atrial fibrillation but are not candidates for warfarin.3,4