Safety and Dosing of Unfractionated Heparin in Fondaparinux-Treated Patients Undergoing Percutaneous Coronary Intervention

Fondaparinux, a synthetic factor Xa inhibitor, has recently emerged as an effective and safe alternative to low-molecular-weight heparin in patients with acute coronary syndromes (ACS). However, fondaparinux does not offer adequate antithrombotic protection during percutaneous coronary intervention (PCI). Although both European and American guidelines recommend adjunctive unfractionated heparin in this setting, they differ on the dose.

In the manufacturer-sponsored FUTURA/OASIS-8 trial, 3235 patients with non–ST-segment elevation ACS were treated with subcutaneous fondaparinux (2.5 mg). The 2026 patients slated for PCI were then randomized to receive unfractionated heparin either at a fixed, low dose (50 U/kg) or at a standard dose (85 U/kg)…