The present invention is aimed to provide a valve prothesis especially used in case of aortic stenosis, which structure is capable of resisting the powerful recoil force and to stand the forceful balloon inflation performed to deploy the valve and to embed it in the aortic annulus. The valve prosthesis comprises an expandable cylindrical metal frame (10), comprising a plurality of intercrossing bars which are sufficiently strong and rigid in an expanded state to resist the recoil forces exerted by the stenotic leaflets of the native aortic valve. The valve prosthesis further comprises an expandable valvular structure (14) composed of valvular tissue compatible with the human body and blood, the valvular tissue being sufficiently supple and resistant to allow the valvular structure to pass from a closed state to an open state to allow blood exerting pressure on the valvular structure to flow.
