BACKGROUND: Contrasting evidence exists on the comparative efficacy and safety of bivalirudin and unfractionated heparin (UFH) in relation to the planned use of glycoprotein IIb/IIIa inhibitors (GPIs).
OBJECTIVES: This study assessed the efficacy and safety of bivalirudin compared with UFH with or without GPIs in patients with acute coronary syndrome (ACS) who underwent invasive management.
METHODS: In the MATRIX (Minimizing Adverse Haemorrhagic Events by Transradial Access Site and Systemic Implementation of AngioX) program, 7,213 patients were randomly assigned to receive either bivalirudin or UFH with or without GPIs at discretion of the operator. The 30-day coprimary outcomes were major adverse cardiovascular events (MACEs) (a composite of death, myocardial infarction, or stroke), and net adverse clinical events (NACEs) (a composite of MACEs or major bleeding).
RESULTS: Among 3,603 patients assigned to receive UFH, 781 (21.7%) underwent planned treatment with GPI before coronary intervention. Bailout use of GPIs was similar between the bivalirudin and UFH groups (4.5% and 5.4%) (p = 0.11). At 30 days, the 2 coprimary endpoints of MACEs and NACEs, as well as individual endpoints of mortality, myocardial infarction, stent thrombosis or stroke did not differ among the 3 groups after adjustment. Compared with the UFH and UFH+GPI groups, bivalirudin reduced bleeding, mainly the most severe bleeds, including fatal and nonaccess site-related events, as well as transfusion rates and the need for surgical access site repair. These findings were not influenced by the administered intraprocedural dose of UFH and were confirmed at multiple sensitivity analyses, including the randomly allocated access site.
CONCLUSIONS: In patients with ACS, the rates of MACEs and NACEs were not significantly lower with bivalirudin than with UFH, irrespective of planned GPI use. However, bivalirudin significantly reduced bleeding complications, mainly those not related to access site, irrespective of planned use of GPIs. (Minimizing Adverse Haemorrhagic Events by Transradial Access Site and Systemic Implementation of AngioX [MATRIX]; NCT01433627).