Human Cardiac Function Simulator for the Optimal Design of a Novel Annuloplasty Ring with a Sub-valvular Element for Correction of Ischemic Mitral Regurgitation

Brian Baillargeon (1) , Ivan Costa (2) , Joseph R. Leach (3) , Lik Chuan Lee (4) , Martin Genet (5, 6) , Arnaud Toutain (6) , Jonathan F. Wenk (7) , Manuel K. Rausch (8) , Nuno Rebelo (1) , Gabriel Acevedo-Bolton (3, 6) , Ellen Kuhl (8) , Jose L. Navia (9) , Julius M. Guccione (6)

1 Dassault Systèmes Simulia Corporation, Fremont, CA, USA
2 UnB - Universidade de Brasilia [Brasília]
3 UC San Francisco - University of California [San Francisco]
4 Michigan State University [East Lansing]
5 IBT - Institute for Biomedical Engineering [ETH Zürich]
6 Department of Medicine [San Francisco]
7 UK - University of Kentucky
8 Stanford University
9 Cleveland Clinic

Ischemic mitral regurgitation is associated with substantial risk of death. We sought to: (1) detail significant recent improvements to the Dassault Systèmes human cardiac function simulator (HCFS); (2) use the HCFS to simulate normal cardiac function as well as pathologic function in the setting of posterior left ventricular (LV) papillary muscle infarction; and (3) debut our novel device for correction of ischemic mitral regurgitation. We synthesized two recent studies of human myocardial mechanics. The first study presented the robust and integrative finite element HCFS. Its primary limitation was its poor diastolic performance with an LV ejection fraction below 20% caused by overly stiff ex vivo porcine tissue parameters. The second study derived improved diastolic myocardial material parameters using in vivo MRI data from five normal human subjects. We combined these models to simulate ischemic mitral regurgitation by computationally infarcting an LV region including the posterior papillary muscle. Contact between our novel device and the mitral valve apparatus was simulated using Dassault Systèmes SIMULIA software. Incorporating improved cardiac geometry and diastolic myocardial material properties in the HCFS resulted in a realistic LV ejection fraction of 55%. Simulating infarction of posterior papillary muscle caused regurgitant mitral valve mechanics. Implementation of our novel device corrected valve dysfunction. Improvements in the current study to the HCFS permit increasingly accurate study of myocardial mechanics. The first application of this simulator to abnormal human cardiac function suggests that our novel annuloplasty ring with a sub-valvular element will correct ischemic mitral regurgitation.

Domaines: Biomécanique [physics.med-ph]

Brian Baillargeon, Ivan Costa, Joseph R. Leach, Lik Chuan Lee, Martin Genet, et al.. Human Cardiac Function Simulator for the Optimal Design of a Novel Annuloplasty Ring with a Sub-valvular Element for Correction of Ischemic Mitral Regurgitation. Cardiovascular Engineering and Technology, 2015, 6 (2), pp.12. ⟨10.1007/s13239-015-0216-z⟩. ⟨hal-01196412⟩