TAVI within failing surgical aortic bioprostheses
Stented valves are primarily constructed using a rigid radiopaque or radiolucent base ring from which a stent or frame is positioned as support for the valve leaflets. This ring is covered by a synthetic fabric or pericardium that protects the frame. A sewing ring is attached here and the three stent posts rise at a right angle to support the valve leaflets which then serve as markers for positioning the transcatheter valves.
Biological stented prostheses are currently the main type of prosthetic valve used for aortic valve replacement with the ratio of bioprostheses to mechanical prostheses reversing itself over the last 15 years. Moreover, the total number of implanted stented bioprostheses has remained stable over the last few years despite competing procedures like stentless prostheses or transcatheter aortic valve implantation.