Failing surgical bioprosthesis in aortic and mitral position

Bioprosthetic heart valves are preferentially selected over mechanical prostheses in the majority of patients undergoing valve replacement surgery. These bioprostheses are prone to structural degeneration, and hence an increasing number of patients are presenting with bioprosthetic failure requiring redo surgery. In selected high-risk cases, successful implantation of a transcatheter aortic valve (TAV) within the failing bioprosthetic surgical aortic valve (SAV) or mitral valve (SMV) has been performed. Herein, we summarise the available evidence, describe the technical challenges, and highlight important procedural considerations for these innovative interventions.