 Although patients with ESRD are at increase risk for cardiovascular disease there are only scant data concerning the cardioprotective effect of antiplatelets drugs for primary or secondary prevention in this population. In a retrospective evaluation of patients with ESRD after acute myocardial infarction, Berger et al. have found that aspirin is underused in this population 67.0 and Similar results were found by McCullough et al., . Balanced against the potential, but unproven benefit of aspirin in patients with ESRD are its potential risks, including bleeding and a possible acceleration of access thrombosis. The evidence for accelerate dialysis access graft thrombosis is based on the work of Himmelfarb and colleagues. In their trial aspirin appeared to increase the relative risk RR1.99 of graft thrombosis. They subsequently demonstrated that, in vitro, aspirin enhanced platelet-derived growth factor-induced vascular smooth muscle proliferation. Adding clopidogrel to aspirin in hemodialysis patients was associated with a significantly increased risk of bleeding and probably would not result in a reduced frequency of graft thrombosis. Although data concerning aspirin for primary or secondary prevention of cardiovascular disease in ESRD patients is not sufficient its efficacy is well proven in the general population. Currently, it seems not ethical to perform a randomized placebo controlled trial to evaluate the antiplatelet protective effect in these patients. The purpose of this study is to perform a prospective evaluation regarding the relationship between platelets function and cardiovascular events in patients with ESRD. 