Effects of glycoprotein IIb/IIIa inhibitors in patients undergoing percutaneous coronary intervention after pretreatment with clopidogrel: a meta-analysis of randomized trials

: Glycoprotein (Gp) IIb/IIIa inhibitors reduce morbidity and mortality in patients undergoing percutaneous coronary intervention (PCI) when added to aspirin and heparin. However, the benefits of Gp IIb/IIIa inhibition in patients pretreated with clopidogrel are less clear. We conducted a meta-analysis to determine the efficacy and safety of adding a Gp IIb/IIIa inhibitor to clopidogrel, aspirin, and heparin before PCI. Five trials were identified via electronic searches of the MEDLINE and Cochrane Central Register of Controlled Trials databases. The studies randomized a total of 5303 patients; 2654 received a Gp IIb/IIIa inhibitor. Two trials examined patients with acute coronary syndromes and 3 examined patients undergoing elective PCI. Loading doses of clopidogrel ranged from 375 to 600 mg. Follow-up ranged from 30 days to 1 year.Gp IIb/IIIa inhibition did not reduce the endpoints of death, myocardial infarction (MI), or target vessel revascularization (odds ratio [OR] = 0.84; 95% confidence interval [CI] = 0.58-1.22, P = 0.35 for death; OR = 0.86; 95% CI = 0.69-1.08, P = 0.19 for MI; and OR = 0.96; 95% CI = 0.81-1.15, P = 0.68 for target vessel revascularization). Analyses restricted to acute coronary syndromes trials yielded similar results (OR = 0.70; 95% CI = 0.33-1.48, P = 0.35 for death; OR = 0.78; 95% CI = 0.59-1.03, P = 0.08 for MI). Gp IIb/IIIa inhibition increased major and minor bleeding (OR = 1.35; 95% CI = 1.04-1.75, P = 0.02) driven by use of abciximab. There was no evidence of heterogeneity in the analyses.