A guide to fluoroscopic identification and design of bioprosthetic valves: a reference for valve-in-valve procedure.

Surgical aortic valve replacement remains the therapy of choice in majority of patients with aortic stenosis. Bioprosthetic heart valves are often preferred over mechanical valves as they preclude the need for anticoagulation with its associated risks of bleeding and thromboembolism. However, bioprosthetic heart valves undergo structural deterioration and eventually fail. Reoperation is the standard treatment for structural failure of the bioprosthetic valve, stenosis or regurgitation but can carry a significant risk, especially in elderly patients with multiple comorbidities. Transcatheter aortic valve implantation has recently been established as a feasible alternative to conventional valve surgery for the management of high-risk elderly patients with aortic stenosis. This treatment modality has also been shown to be of benefit in the management of degenerated aortic bioprosthesis as a valve-in-valve procedure. The success of this procedure depends on a good understanding of the failing bioprostheses. This not only includes the device design but its radiological/fluoroscopic appearance and how it correlates with the implanted valve, as transcatheter aortic valve implantation is performed under fluoroscopic guidance. Here we illustrate the fluoroscopic appearance of 11 commercially available surgical bioprostheses and two commercially available transcatheter heart valves and discuss important aspects in their design which can influence outcome of a valve-in-valve procedure. We have also collated relevant information on the aspects of the design of a bioprosthetic valve, which are relevant to the valve-in-valve procedure.