The place of fondaparinux in the ESC and ACC/AHA guidelines for anticoagulation in patients with non-ST elevation acute coronary syndromes

The European Society of Cardiology (ESC) and American College of Cardiology/American Heart Association (ACC/AHA) Practice Guidelines Committees recently published new guidelines on the management of patients with non-ST elevation acute coronary syndromes (NSTE-ACS). In both guidelines, the use of an anticoagulant drug (unfractionated heparin, enoxaparin, bivalirudin, or fondaparinux) became a class IA recommendation. As bleeding events impact survival prognosis, the main focus of new anticoagulant strategies has been on limiting major bleeding complications associated with their use, while maintaining a high level of efficacy. In patients with NSTE-ACS, fondaparinux, the first selective factor Xa inhibitor approved for use in this setting, exhibited similar short-term efficacy compared with enoxaparin, but reduced major bleeding and 30 day mortality. Therefore, in the context of early invasive or conservative strategy, fondaparinux was given a prominent place (class I recommendation) by both societies, notably in patients at risk of bleeding. Fondaparinux was preferred over enoxaparin (class IA vs. IIa-B) in the ESC guidelines, regardless of initial strategy (excluding urgent revascularization for life-threatening conditions). In the ACC/AHA guidelines, fondaparinux was considered the drug of choice in conservative strategy. In fondaparinux patients undergoing invasive procedures, it was recommended to add unfractionated heparin. Fondaparinux was proposed as a drug of choice in patients with renal dysfunction.