The challenge of interpreting comparative TAVI studies

Over the last 20 years, the evolution in transcatheter aortic valve implantation (TAVI) has resulted in several devices becoming commercially available for selection. Transcatheter aortic valves (TAVs) exhibit significant heterogeneity in the design of their stent frame, leaflets and/or method of implantation, rendering specific TAVs potentially more or less favourable for specific patient anatomies. The anatomy of patients with severe aortic stenosis (AS) can vary significantly based on the underlying aortic valve phenotype (tricuspid, bicuspid), distribution and degree of leaflet calcification, size of the aortic annulus and aortic root, and height of the coronary ostia. Consequently, studies evaluating which valve designs perform favourably in specific anatomical scenarios are necessary to enable physicians to adopt a more patient-tailored approach, which is increasingly relevant given the expansion of TAVI into younger and more complex patient cohorts.

In this issue of EuroIntervention, Yamamoto et al1 present a study comparing outcomes obtained with the Navitor (n=518; Abbott) versus Evolut FX (n=401; Medtronic) TAV in patients with a small aortic annulus (area <430 mm2). Both are self-expanding TAVs, with the Navitor having an intra-annular leaflet...