Rivaroxaban or Aspirin for Biological Aortic Prosthesis

• Status: Recruiting
• Trial end date: 2022-11-01
• Target enrollment: 0
• Participant gender: All

Summary

Aortic valve replacement with a biological prosthesis is the most common valve surgery performed with about 1000 operations performed in Denmark each year. Further, the introduction of percutaneous stent valves will increase these types of replacements in the years to come. A biological valve is a foreign body prone to cause thrombus formation at least until the valve is covered with recipient endothelium. There are no conclusive studies of anticoagulation and the investigators have shown stroke to be a common complication. Guidelines have variably recommended aspirin or rivaroxaban for anticoagulation, and currently aspirin is the most common recommendation. In a register study, the investigators have shown that proper anticoagulation with warfarin is likely to be superior. There is a clear need for a large randomised study of aspirin versus anticoagulation for biological aortic valve replacement. This protocol describes a randomised study where 1000 patients will be randomised to receive either rivaroxaban or aspirin for 6 months following aortic valve replacement with a biological prosthesis. The primary efficacy endpoint is a combined event of all-cause mortality and hospitalisation for either acute myocardial infarction or stroke. This study has the power to settle a discussion of appropriate anticoagulation for this operation

• Phase: Phase 4
• Accepts Healthy Volunteers?: No

Details

• Lead Sponsor: Christian Torp-Pedersen
• Collaborators: Aalborg Universitetshospital; Aalborg University Hospital; Aarhus University Hospital; Odense University Hospital; Rigshospitalet, Denmark
• Treatments: Aspirin; Rivaroxaban

Criteria

Inclusion Criteria:

1. Patients ≥ 18 years scheduled for surgical bioprosthetic aortic valve replacement.

2. Ability to understand the study background, risk and benefit of treatment and to give written informed consent

3. Scheduled for routine antithrombotic treatment after surgical valve replacement. Patient required to receive aspirin due to simultaneous by-pass operation are allowed in the study - to receive either aspirin alone or rivaroxaban in addition to aspirin.

Exclusion Criteria:

1. Ongoing treatment with oral anticoagulants (warfarin, phenprocoumon or thrombin/factorXa oral anticoagulants).

2. Indication for oral anticoagulation treatment even if currently not treated (e.g. chronic atrial fibrillation, recent deep vein thrombosis, recent pulmonary embolism)

3. Indication for dual antiplatelet therapy (e.g. aspirin and ADP receptor inhibitor)

4. Known intolerance to aspirin or rivaroxaban.

5. Stroke within 6 months of study start.

6. Concomitant therapy with systemic drugs that are strong inhibitors of both CYP 3A4 and P-gp (azole antimycotics such as ketoconazole and itraconazole or HIV protease inhibitors such as ritonavir)

7. Concomitant therapy with drugs that are strong CYP 3A4 inducers (e.g. carbamazepine, phenytoin, rifampin, St. John's wort)

8. Platelet count of less than 90,000 per cubic millimeter

9. Preoperative anemia with hemoglobin <6mmol/l

10. Creatinine clearance (Cockroft formula) <15 ml/min

11. Clinically significant gastrointestinal bleeding within 3 months

12. Previous intracranial hemorrhage;

13. The presence of a severe or active bleeding disorder.

14. Non-adherence to medications

15. Pregnancy or risk of pregnancy. In women of childbearing age, an approved birth control must be ensured.