Abstract
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.
Original language | English |
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Pages (from-to) | 105-116 |
Number of pages | 12 |
Journal | Cardiovascular Engineering and Technology |
Volume | 6 |
Issue number | 2 |
DOIs | |
State | Published - Jun 1 2015 |
Bibliographical note
Funding Information:This work was performed as part of the Living Heart Project. The authors thank Pamela Derish in the Department of Surgery, UCSF, for proofreading the manuscript. This work was supported by NIH Grants R01-HL-077921 and R01-HL-118627 (J.M. Guccione) and U01-HL-119578 (J.M. Guccione and E. Kuhl); K25-NS058573-05 (G. Acevedo-Bolton); and Marie-Curie International Outgoing Fellowship within the 7th European Community Framework Program (M. Genet). Ellen Kuhl also acknowledges support by the National Science Foundation CAREER award CMMI 0952021, by the National Science Foundation INSPIRE grant 1233054, and by the National Institutes of Health Grant U54 GM072970. Ivan Costa acknowledges support by the Brazilian Science Agency CNPq Grants 474831/2012-4 and 245677/2012-7.
Publisher Copyright:
© 2015, The Author(s).
Keywords
- Finite element method
- Ischemic mitral regurgitation
- Mitral annuloplasty
- Myocardial infarction
- Realistic simulation
- Ventricular function
ASJC Scopus subject areas
- Biomedical Engineering
- Cardiology and Cardiovascular Medicine