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Abstract: TH-PO1193

Multicenter RCT of Vitamin K Antagonist Replacement by Rivaroxaban with or Without Vitamin K2 in Hemodialysis Patients with Atrial Fibrillation: The Valkyrie Study

Session Information

Category: Dialysis


  • De Vriese, An S., AZ Sint-Jan Brugge - Oostende AV, Brugge, Belgium
  • Caluwé, Rogier, OLV Hospital Aalst, Aalst, Belgium
  • Pyfferoen, Lotte, AZ Sint-Jan Brugge-Oostende AV, Brugge, Belgium
  • De Bacquer, Dirk, Ghent University, Ghent, Belgium
  • De Boeck, Koen, ZNA Middelheim, Antwerpen, Belgium
  • Delanote, Joost Lmc, AZ Sint-Jan Brugge-Oostende AV, Brugge, Belgium
  • De Surgeloose, Didier P., ZNA Middelheim, Antwerpen, Belgium
  • Van Vlem, Bruno, OLV Hospital Aalst, Aalst, Belgium
  • Verbeke, Francis, University Hospital Ghent, Ghent, Belgium

Vitamin K antagonists (VKA) have been incriminated as probable cause of accelerated vascular calcification (VC) in hemodialysis patients. Functional vitamin K deficiency may further contribute to their susceptibility for VC. We investigated the effect of vitamin K status on VC progression in 132 hemodialysis patients with atrial fibrillation treated with VKA or qualifying for anticoagulation.


Patients were randomized to VKA, rivaroxaban 10 mg od, or rivaroxaban plus vitamin K2 2000 µg trice weekly during 18 months. Systemic dp-ucMGP levels were quantified to assess vascular vitamin K status. Cardiac and thoracic aorta calcium scores and pulse wave velocity were measured to evaluate VC progression.


Initiation or continuation of VKA increased dp-ucMGP, while levels decreased in the rivaroxaban group and to a larger extent in the rivaroxaban+vitamin K2 group, but remained nevertheless elevated (Figure). Changes in coronary artery, thoracic aorta and cardiac valve calcium scores and pulse wave velocity were not different among the treatment arms. All cause death, stroke, cardiovascular event and bleeding rates were not significantly different between the groups. The incidence of life-threatening and major bleeding was significantly lower in the pooled rivaroxaban arms than in the VKA arm.


Withdrawal of VKA and high-dose vitamin K2 improve vitamin K status in hemodialysis patients, but have no significant favorable effect on VC progression. Severe bleeding complications may be lower with rivaroxaban than with VKA.

Estimated marginal mean changes in dp-ucMGP levels from baseline (95% CI).


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