Tricuspid valve edge-to-edge repair simulations are highly sensitive to annular boundary conditions

Collin E Haese; Vijay Dubey; Mrudang Mathur; Alison M Pouch; Tomasz A Timek; Manuel K Rausch

doi:10.1016/j.jmbbm.2024.106879

Tricuspid valve edge-to-edge repair simulations are highly sensitive to annular boundary conditions

J Mech Behav Biomed Mater. 2024 Dec 22:163:106879. doi: 10.1016/j.jmbbm.2024.106879. Online ahead of print.

Authors

Collin E Haese¹, Vijay Dubey¹, Mrudang Mathur², Alison M Pouch³, Tomasz A Timek⁴, Manuel K Rausch⁵

Affiliations

¹ Department of Mechanical Engineering, The University of Texas at Austin, 204 E. Dean Keeton Street, Austin, TX, 78712, USA.
² Department of Cardiothoracic Surgery, Stanford University, 870 Quarry Rd Extension, Palo Alto, CA, 94304, USA.
³ Department of Radiology, University of Pennsylvania, 3700 Hamilton Walk, Philadelphia, PA, 19104, USA.
⁴ Division of Cardiothoracic Surgery, Corewell Health West, Michigan State University College of Human Medicine, 100 Michigan Ave SE, Grand Rapids, MI, 49503, USA.
⁵ Department of Mechanical Engineering, The University of Texas at Austin, 204 E. Dean Keeton Street, Austin, TX, 78712, USA; Department of Aerospace Engineering & Engineering Mechanics, The University of Texas at Austin, 2617 Wichita Street, Austin, TX, 78712, USA; Department of Biomedical Engineering, The University of Texas at Austin, 107 W. Dean Keeton Street, Austin, TX, 78712, USA; The Oden Institute for Computational Engineering & Sciences, The University of Texas at Austin, 201 E. 24th Street, Austin, TX, 78712, USA. Electronic address: [email protected].

PMID: 39742687
DOI: 10.1016/j.jmbbm.2024.106879

Abstract

Transcatheter edge-to-edge repair (TEER) simulations may provide insight into this novel therapeutic technology and help optimize its use. However, because of the relatively short history and technical complexity of TEER simulations, important questions remain unanswered. For example, there is no consensus on how to handle the annular boundary conditions in these simulations. In this short communication, we tested the sensitivity of such simulations to the choice of annular boundary conditions using a high-fidelity finite element model of a human tricuspid valve. Therein, we embedded the annulus among elastic springs to simulate the compliance of the perivalvular myocardium. Next, we varied the spring stiffness parametrically and explored the impact on two key measures of valve function: coaptation area and leaflet stress. Additionally, we compared our results to simulations with a pinned annulus. We found that a compliant annular boundary condition led to a TEER-induced "annuloplasty effect," i.e., annular remodeling, as observed clinically. Moreover, softer springs led to a larger coaptation area and smaller leaflet stresses. On the other hand, pinned annular boundary conditions led to unrealistically high stresses and no "annuloplasty effect." Furthermore, we found that the impact of the boundary conditions depended on the clip position. Our findings in this case study emphasize the importance of the annular boundary condition in tricuspid TEER simulations. Thus, we recommend that care be taken when choosing annular boundary conditions and that results from simulations using pinned boundaries should be interpreted with caution.