Although vitamin K antagonists (VKAs) may accelerate bioprosthetic valve calcification by inhibiting matrix Gla protein, a key regulator of vascular and valvular mineralization,13, 14, 15 direct oral anticoagulants (DOACs) may protect the bioprosthesis from the deleterious elevated level of Factor Xa in patients with severe aortic stenosis.16 Here, F10 is linked to aortic stenosis.