Early stent thrombosis with bivalirudin in patients undergoing percutaneous coronary intervention

Although bivalirudin has been shown to reduce bleeding events in patients undergoing percutaneous coronary intervention, residual concerns remain about a possible higher risk of early (within 30 days) stent thrombosis (ST). Therefore, we performed a meta-analysis of randomised trials reporting ST events with bivalirudin compared to other antithrombotic therapies (heparins ± glycoprotein IIb/IIIa inhibitors). A systematic literature search of electronic resources was performed through May, 2014. The primary endpoint was definite early ST, according to Academic Research Consortium criteria. Secondary endpoints included: all-cause death, myocardial infarction and major bleeding. A total of 11 trials, including 16,415 patients, were accrued. Compared to other regimens, bivalirudin significantly increased the risk of early ST (odds ratio [OR]=1.80; 95 % confidence interval [CI], 1.28-2.52; p=0.0007) and reduced the risk of major bleeding (OR [95 %CI]=0.64 [0.51-0.82], p=0.0003), with a comparable risk of mortality or myocardial infarction. The higher risk of early ST was mainly attributable to acute (OR [95 % CI] =4.33 [2.33-8.05], p < 0.001) than subacute (OR [95 % CI] =0.89 [0.53-1.50], p =0.67) ST events (p for interaction < 0.001). Non-fatal myocardial infarction was the most common presentation (83 %) of early ST events, while death occurred infrequently (about 5 %). In conclusion, in patients undergoing PCI, bivalirudin compared to heparins is associated with a higher risk of early ST, which is mainly related to more frequent acute events. Further studies are required to evaluate alternative strategies to mitigate this risk, without hampering the benefits derived from the reduction in bleeding events with bivalirudin.