TAVI in 2022: Remaining issues and future direction

Since the first-in-human procedure in 2002, transcatheter aortic valve implantation (TAVI) has become a well-established therapeutic option for severe aortic stenosis, and is offered increasingly to patients at lower surgical risk, who are typically younger. Increasing lifespan carries concerns that "minor" complications that may have little impact in elderly patients could have a greater long-term impact in younger patients. Issues such as mild paravalvular regurgitation, hypoattenuated leaflet thickening, atrioventricular block with need for permanent pacemaker implantation or future coronary access may have a substantial cumulative undesirable impact. Additionally, as with surgical bioprosthetic valves, transcatheter bioprosthetic valves will eventually degenerate, and may require repeat intervention. Although durability data for transcatheter heart valves (THVs) is encouraging, very late data are lacking. Redo TAVI has been shown to be feasible with acceptable outcomes in patients with failed THVs, but in some patients, anatomical or device considerations may preclude a repeatable procedure because of the risk of coronary obstruction. Various strategies for lifetime management in this lower-risk and younger population have been proposed: surgical aortic valve replacement (SAVR) first, followed by TAVI; TAVI then SAVR; TAVI then TAVI, etc. A tailored approach may be considered according to patient co-morbidities, anatomy and the relative advantages and disadvantages of the two therapies. This review offers an overview of current challenges when considering TAVI in populations at lower risk, and summarizes the different approaches that have been developed to address these concerns.