Finite element analysis of annuloplasty and papillary muscle relocation on a patient-specific mitral regurgitation model

• Authors: Fanwei Kong, Georgia Institute of Technology; Thuy Pham, Georgia Institute of Technology; Caitlin Martin, Georgia Institute of Technology; John Elefteriades, Yale University; Raymond McKay, The Hartford Hospital; Charles Primiano, The Hartford Hospital; Wei Sun, Emory University
• Journal Title: PLoS ONE
• Volume: Volume 13, Number 6
• Publisher: Public Library of Science | 2018-06-14, Pages e0198331-e0198331
• Type of Work: Article | Final Publisher PDF
• Publisher DOI: http://doi.org/10.1371/journal.pone.0198331
• Subjects: Engineering, Biomedical; Health Sciences, General

Abstract

Objectives: Functional mitral regurgitation (FMR) is a significant complication of left ventricle (LV) dysfunction associated with poor prognosis and commonly treated by undersized ring annuloplasty. This study aimed to quantitatively simulate the treatment outcomes and mitral valve (MV) biomechanics following ring annulopalsty and papillary muscle relocation (PMR) procedures for a FMR patient. Methods: We utilized a validated finite element model of the left heart for a patient with severe FMR and LV dilation from our previous study and simulated virtual ring annuloplasty procedures with various sizes of Edwards Classic and GeoForm annuloplasty rings. The model included detailed geometries of the left ventricle, mitral valve, and chordae tendineae, and incorporated age- and gender- matched nonlinear, anisotropic hyperelastic tissue material properties, and simulated chordal tethering at diastole due to LV dilation. Results: Ring annuloplasty with either the Classic or GeoForm ring improved leaflet coaptation and increased the total leaflet closing force while increased posterior mitral leaflet (PML) stresses and strains. Classic rings resulted in larger coaptation forces and areas compared to GeoForm rings. The PMR procedure further improved the leaflet coaptation, decreased the PML stress and strain for both ring shapes and all sizes in this patient model. Conclusions: This study demonstrated that a rigorously developed patient-specific computational model can provide useful insights into annuloplasty repair techniques for the treatment of FMR patients and could potentially serve as a tool to assist in pre-operative planning for MV repair surgical or interventional procedures.