Effect of clopidogrel pretreatment on ischemic complications of percutaneous coronary intervention among bivalirudin-treated patients (from the EVENT registry)

Although clopidogrel pretreatment benefits patients undergoing percutaneous coronary intervention (PCI) for acute coronary syndromes, these benefits are less well established among patients undergoing elective PCI--in particular, when they are treated with the direct thrombin inhibitor, bivalirudin. We used data from the multicenter Evaluation of Drug Eluting stents and ischemic Events registry to assess the association between clopidogrel pretreatment and PCI-related complications among patients undergoing elective PCI with bivalirudin as the antithrombotic regimen. The primary end point was the composite of in-hospital death or myocardial infarction. From January 2005 and December 2007, 4,681 patients underwent elective PCI at 55 United States centers, and 1,913 (41%) received bivalirudin as the planned anticoagulant. Clopidogrel pretreatment was used in 923 patients (48%). The incidence of in-hospital death or myocardial infarction was similar among patients who did and did not receive clopidogrel pretreatment (5.5% vs 5.8%, p = 0.83). This result was unchanged in propensity-adjusted analyses (adjusted odds ratio for pretreatment 0.91, 95% confidence interval 0.60 to 1.39, p = 0.66). Also, no differences were seen in the in-hospital bleeding events (1.0% vs 1.0%, p = 0.94) or 1-year ischemic complications between the 2 treatment groups (7.5% vs 8.3%, p = 0.26). In conclusion, among unselected patients undergoing elective PCI with bivalirudin as the planned anticoagulant, clopidogrel pretreatment was common but was not associated with a reduced risk of ischemic complications.