TAVI and valve performance: update on definitions, durability, transcatheter heart valve failure modes and management.

Aortic bioprostheses are increasingly used both for surgery, as an alternative to mechanical valves, and for transcatheter implantation in patients with severe aortic stenosis. Transcatheter aortic valve implantation (TAVI) has been widely adopted for the treatment of severe symptomatic aortic stenosis in elderly (>75 years) patients who are at risk for surgery and who have favourable transfemoral access. It is already under evaluation in low-risk patients. The aim of this review is to present an update on definitions and to assess the various forms of transcatheter heart valve failure and their management: structural valve deterioration, non-structural deterioration, thrombosis and endocarditis.