Andexanet alpha-induced heparin resistance treated by nafamostat mesylate in a patient undergoing total aortic arch repair for Stanford type A acute aortic dissection: a case report.

Background: Andexanet alfa, an anti-Xa inhibitor antagonist, induces heparin resistance. Here, we report a case of successful management of cardiopulmonary bypass with andexanet alfa-induced heparin resistance using nafamostat mesylate.

Case Presentation: An 84-year-old female, with Stanford type A acute aortic dissection, underwent an emergency surgery for total aortic arch replacement. Andexanet alfa 400 mg was administered preoperatively to antagonize edoxaban, an oral Xa inhibitor. Heparin 300 IU/kg was administered before cardiopulmonary bypass, and the activated clotting time (ACT) was 291 s. The ACT was 361 s after another administration of heparin 200 IU/kg. According to our routine therapy for heparin resistance, an initial dose of nafamostat mesylate 10 mg was administered intravenously, followed by a continuous infusion of 20-30 mg/h. The ACT was prolonged to 500 s, and cardiopulmonary bypass was successfully established thereafter.

Conclusions: This case report presents the successful management of cardiopulmonary bypass with andexanet alfa-induced heparin resistance using nafamostat mesilate. This report presents the successful management of cardiopulmonary bypass with andexanet alfa-induced heparin resistance using nafamostat mesilate.