Numerical models of valve-in-valve implantation: effect of intentional leaflet laceration on the anchorage.

Abstract

Transcatheter aortic valve implantation (TAVI) is currently recommended in practice guidelines for patients who are at intermediate to high surgical risk for surgical aortic valve replacement. Coronary artery obstruction is a fatal complication of TAVI that occurs in up to 3.5% of the implantations inside a failed surgical bioprosthetic valve (valve-in-valve, ViV). A new technique to address this problem is intentional laceration of the bioprosthetic leaflets, known as BASILICA. In this technique, the leaflets are lacerated to prevent coronary obstruction and may also help in preventing leaflet thrombosis. Our hypothesis is that this technique may harm the circumferential stress in the surgical valve and weaken the anchorage of the TAVI device. This study aims to compare the anchorage post-ViV implantations, with and without lacerations, using numerical modelling. Deployments of TAVI stents (Medtronic Evolut PRO; Edwards SAPIEN 3) inside an externally mounted surgical bioprosthetic valve (Sorin Mitroflow) were modelled by finite element analysis. The results show that each laceration reduces the contact area of the TAVI stent with its landing zone and that the anchorage contact force weakens. The BASILICA technique has lesser effect on the anchorage contact area and forces in the SAPIEN than in the Evolut cases, because the balloon inflation is less sensitive to the deployment region. TAVI stent migration was not found in any of the models. These results can help expanding the use of leaflet laceration by choosing a better matched TAVI devices for the BASILICA technique.