Intracoronary Bivalirudin Bolus in ST-Elevation Myocardial Infarction Patients Treated with Primary Angioplasty: Theoretical Bases, Clinical Experience, and Future Applications

Intracoronary thrombus is a common finding in acute coronary syndromes and often correlates with adverse prognosis and complications during percutaneous coronary interventions (PCIs). Bivalirudin, a direct thrombin inhibitor, is one of the recommended antithrombotic treatments for PCI in ST-elevation myocardial infarction (STEMI). The intracoronary administration of a bivalirudin loading dose, even if off-label, offers theoretical advantages over the standard intravenous route, providing a very high drug concentration in the infarct-related artery without increasing the total dose of the drug administered. After the description in case reports of such an approach, a larger scale experience was recently reported in a large cohort of patients with STEMI treated during primary PCI with a bivalirudin intracoronary loading dose followed by the standard intravenous maintenance infusion. As a control group, a propensity score-matched cohort of patients undergoing primary PCI treated with intravenous bivalirudin in the same institution was selected. Compared with the intravenous bolus, the intracoronary administration of bivalirudin was associated with improved ST-segment resolution, lower post-procedural peak CK-MB levels, and better Thrombolysis in Myocardial Infarction (TIMI) frame count values, without difference in bleeding rates. Thus, this new promising antithrombotic strategy, based on the intracoronary administration of a bivalirudin loading dose during primary PCI, appeared safe, improved myocardial reperfusion, and mitigated enzymatic myocardial infarct size compared with the standard intravenous protocol. Randomized trials are warranted to confirm these results and evaluate the possible long-term clinical benefits.

Contemporary anticoagulation therapy in patients undergoing percutaneous intervention

The proper use of anticoagulants is crucial for ensuring optimal patient outcomes post percutaneous interventions in the cardiac catheterization laboratory. Anticoagulant agents such as unfractionated heparin, a thrombin inhibitor; low-molecular weight heparins, predominantly Factor Xa inhibitors; fondaparinux, a Factor Xa inhibitor and bivalirudin, a direct thrombin inhibitor have been developed to target various steps in the coagulation cascade to prevent formation of thrombin. Optimal anticoagulation achieves the correct balance between thrombosis and bleeding and is related to optimal outcomes with minimal complications. This review will discuss the mechanisms and appropriate use of current and emerging anticoagulant therapies used during percutaneous interventions.