Feasibility of redo-TAVI in the self-expanding ACURATE neo2 valve: a computed tomography study

Abstract

Background: Redo-transcatheter aortic valve implantation (TAVI) may be unfeasible because of the risk of compromising coronary flow or coronary access by the pinned back leaflets of the index transcatheter aortic valve.

Aims: We aimed to evaluate the feasibility of redo-TAVI using the balloon-expandable SAPIEN 3 (S3) implanted within the self-expanding ACURATE neo2 (ACn2) valve and to identify predictors associated with a high risk of compromising coronary flow.

Methods: A total of 153 post-ACn2 TAVI cardiac computed tomography scans were analysed. Redo-TAVI using an S3 was simulated in two positions: S3 outflow to the ACn2 upper crown (low implant) and S3 outflow to the base of the ACn2 commissural posts (high implant). The risk for coronary flow compromise and inaccessibility was determined by the height of the neoskirt created by the pinned back leaflets and the valve-to-aorta distances.

Results: At a low S3 implant position, risk of coronary flow compromise was predicted in only 8% of patients and this increased to 60% with a high S3 position. In accordance, coronary access was predicted to be unrestricted in 52% versus 13% of patients with a low versus high S3 implantation. Female sex, a small aortic annular dimension and a sinotubular junction-to-aortic annulus mean diameter ratio <1.15 were independent predictors associated with a high risk for coronary flow compromise.

Conclusions: The feasibility of redo-TAVI with an S3 in an ACn2 depends on the implant depth of the S3 and the geometry of the surrounding aorta. A low S3 implant may reduce the risk of coronary flow compromise and inaccessibility.