Bivalirudin versus heparin in patients planned for percutaneous coronary intervention: a meta-analysis of randomised controlled trials

Background Bivalirudin is an alternative to heparin in patients undergoing percutaneous coronary intervention (PCI). We aimed to define the effects of a bivalirudin-based anticoagulation regimen compared with a heparin-based anticoagulation regimen on ischaemic and bleeding outcomes. Methods We searched Medline, the Cochrane Library, and relevant meeting abstracts (search done on April 9, 2014) for randomised trials that assessed bivalirudin versus heparin in patients planned for PCI. The primary efficacy endpoint was the incidence of major adverse cardiac events (MACE) up to 30 days. Secondary efficacy endpoints were death, myocardial infarction, ischaemia-driven revascularisation, and stent thrombosis. The primary safety endpoint was major bleeding up to 30 days. We calculated pooled risk ratios and 95% CIs using random-effects models. Findings We included data from 16 trials involving 33 958 patients, of whom 2422 experienced MACE and 1406 had a major bleed. There was an increase in the risk of MACE with bivalirudin-based regimens compared with heparin-based regimens (risk ratio 1.09, 95% CI 1.01-1 17; p=0.0204), which was largely driven by increases in myocardial infarction (1.12, 1.03-1.23) and seemingly also by ischaemia-driven revascularisation (1.16, 0.997-1.34) with bivalirudin compared with heparin, with no effect on mortality (0 99, 0 82-1.18). Bivalirudin increased the risk of stent thrombosis (risk ratio 1.38, 95% CI 1.09-1.74; p=0.0074), which was primarily due to an increase in acute cases in ST-segment elevation myocardial infarction (4.27, 2.28-8 00; p<0 0001). Overall, bivalirudin-based regimens lowered the risk of major bleeding (risk ratio 0.62, 95% CI 0 49-0.78; p<0 0001), but the magnitude of this effect varied greatly (p<0 0001) depending on whether glycoprotein IIb/IIIa inhibitors were used predominantly in the heparin arm only (0.53, 0.47-0 61; p<0 0001), provisionally in both arms (0.78, 0.51-1.19; p=0 25), or planned in both arms (1.07, 0.87-1.31; p=0 53). Interpretation Compared with a heparin-based regimen, a bivalirudin-based regimen increases the risk of myocardial infarction and stent thrombosis, but decreases the risk of bleeding, with the magnitude of the reduction depending on concomitant glycoprotein IIb/IIIa inhibitor use. Physicians should weigh the trade-off between ischaemic and bleeding events when choosing between different anticoagulant regimens.