The direct oral anticoagulants (DOACs) and particularly the FXa inhibitors are a concern in patients presenting with type A aortic dissection as this may contribute to severe bleeding complications. The antidote andexanet alfa (Ondexxya®) can interact with the heparin- anti-thrombin III (ATIII) complex which may neutralize the anticoagulant effect of heparin and the use of andexanet alfa before surgery necessitating heparin-anticoagulation has been reported to cause unresponsiveness to heparin. The investigators have preliminary in-vitro data demonstrating the ability to remove apixaban from reconstituted blod by hemadsorption and are now analyzing if aFXa inhibitor levels may be reduced by hemadsorption in the clinical setting analyzing this in patients using FXa inhibitors being operated acutely for type A aortic dissection.

Inclusion Criteria:

• Indication for urgent surgery for proximal aortic disease
• Treatment with FXa inhibitor for more than 2 weeks
• Measured concentration of FXa inhibitor in therapeutic range (>50 ng/mL) at the time of admission.
• Intraoperative use of Cytosorb® hemadsorber.

Exclusion Criteria:

• Low FXa inhibitor concentration (<50 ng/mL) at the time of admission

Patients who are anticoagulated with FXa inhibitors beeing operated acutely for acute proximal aortic disease with the use of Cytosorb® hemadsorber intraoperatively.