Simulation of Transcatheter Therapies for Atrioventricular Valve Regurgitation in an Open-Source Finite Element...

Transcatheter edge-to-edge repair (TEER) and annuloplasty devices are increasingly used to treat mitral valve regurgitation, yet their mechanical effects and interactions remain poorly understood. This study aimed to establish an open-source finite element modeling (FEM) framework for simulating patient-specific mitral valve repairs and to evaluate how TEER, annuloplasty, and combined strategies influence leaflet coaptation and valve mechanics. A central objective was to demonstrate how such simulations may support surgical planning by identifying optimal interventions.

A patient-specific mitral valve model was reconstructed using SlicerHeart and 3D Slicer. Four G4 MitraClip geometries were modeled and deployed in FEBio to capture leaflet grasp and subsequent clip-leaflet motion under physiologic pressurization. CardioBand annuloplasty was simulated by reducing annular circumference via displacement-controlled boundary conditions, and Mitralign suture annuloplasty was modeled using discrete nodal constraints. Simulations were performed for prolapse and dilated annulus cases, comparing repairs individually and in combination. Valve competence (regurgitant orifice area, ROA), coaptation/contact area (CA), and leaflet stress and strain distributions were quantified.

In the prolapse anatomy, the simulations showed that while TEER restored coaptation, it also increased the stresses on the leaflets, whereas band and suture annuloplasty generated distinct morphologies with lower stresses. In the dilation anatomy, TEER alone left residual regurgitation, and annuloplasty improved the leaflet closure. Quantitatively, the model found that combined TEER + band annuloplasty yielded the smallest ROA (0.06 ${\text{cm}}^2$ ), the largest CA (2.57 ${\text{cm}}^2$ ), and reduced stresses relative to TEER alone.

This study establishes a reproducible, open-source FEM framework for simulating transcatheter TEER and annuloplasty repairs. The framework enables quantitative evaluation of the mechanical impact of different transcatheter valve repair strategies, offers a foundation for extending virtual repair analyses to additional valve geometries, and supports the broader goal of incorporating virtual repair into procedure planning.