Bivalirudin Is Associated With Better Clinical Outcomes As Opposed To Unfractionated Heparin In Patients Undergoing Primary Percutaneous Coronary Intervention

Objectives: Prevention of adverse ischemic events during and after primary percutaneous coronary intervention (PCI) in patients with acute myocardial infarction (AMI) is the essential role of antithrombotic therapy. The clinical outcomes and efficacy of these antithrombotic agents should be weighed in against their relative risks of hemorrhagic complications. The aim of this study was to compare the effect of bivalirudin with unfractionated heparin (UFH) anticoagulant therapies in patients with AMI undergoing primary PCI and to elucidate their clinical prognostic significance. Materials and methods: We performed a prospective, open label multicenter trial in which patients with AMI undergoing primary PCI were randomized to bivalirudin or heparin alone. A total of 459 patients were consecutively enrolled between June 2013 and July 2015. The anti-thrombotic strategy was decided upon by the operator. Patient age ranged from 18 to 80 years. The patients were admitted with AMI within 12 hours after symptom onset or within 12 to 24 hours with ongoing chest pain, with ST-segment elevation, or with a new left bundle branch block, and consequently underwent primary PCI with an approved device. Patients were assigned to 2 cohorts. The first group received bivalirudin as a bolus of 0.75 mg/Kg followed by an infusion of 1.75 mg/Kg/h during the PCI procedure for a median of 3 hours. The second group received UFH monotherapy as an intravenous bolus of 100 IU/Kg, according to the current guidelines, with subsequent boluses targeted to an activated clotting time (ACT) of > 200 seconds. Results: The incidence of stroke (hemorrhagic) and stent thrombosis were similar in both the bivalirudin and heparin cohorts (0.9 vs. 2.97% and 0.9 vs. 1.27%, respectively). There was however a significant difference in the all-cause bleeding cases in the bivalirudin arm as opposed to the heparin arm (5.38 vs. 13.98%; relative risk [RR] for bivalirudin vs. heparin, 0.3848; 95% Cl= 0.2039-0.7262; P= 0.002). Nine patients (4.04%) treated with bivalirudin while 25 (10.59%) treated with heparin only, experienced a statistical significant difference in all bleeding events (including access and non-access sites) at the primary 30-day endpoint (relative risk [RR]= 0.3810; 95% CI= 0.1818-0.7983), P= 0.0073). The rates of major adverse cardiac or cerebral events (4.48% vs. 9.32%; RR= 0.4329; 95% CI= 0.2037-0.9200, P= 0.0241) and its individual components were also statistically significant between the 2 groups. In addition, there was a statistically significant difference in the rates of severe bleeding in the bivalirudin vs. heparin cohorts (0.45% vs. 5.51%; RR= 0.0814; 95% CI= 0.01073-0.6175, P= 0.0016) after 30 days. Conclusion: We put forward that bivalirudin was associated with significant reductions in all-cause bleeding, severe bleedings and major adverse coronary and cerebral events (MACCE) following prolonged hospitalization (30 days). The use of bivalirudin further cements its role as a novel and potent anti-thrombin drug, greatly superior to heparin.