The purpose of this research training fellowship is to provide the candidate with a unique opportunity to learn the interdisciplinary knowledge of heart valve disease and its treatment using engineering tools. The candidate will learn how to apply engineering mechanics principles, computational technologies and biomedical sciences to solve clinical issues related to heart valve disease treatment. To accomplish this training plan, the candidate will conduct research to investigate the biomechanics involved in minimally invasive mitral valve repair, through a combined experimental and computational study, to better understand underlying valve repair mechanisms, and to facilitate novel intervention device design. Specifically, the following specific aims will be achieved: 1) Quantify the elastic properties of coronary sinus (CS)/great cardiac vein (GCV), and mitral valve tissues as well as adjacent myocardium. 2) Utilize constitutive models to accurately model tissue properties. 3) Generate 3D Finite Element (FE) models of the mitral valve apparatus from excised human hearts and cardiac CT images, and validate the FE models. Methods: The candidate will perform a series of experiments to characterize mitral tissue properties. Histology analysis will be conducted to study the microstructures of tissues and to understand tissue structure-function relations. A rigorous strain energy function will be applied to accurately model the tissue properties, which will in turn be incorporated into FE simulations. 3D geometries of associated tissues will be recreated from physical measurements of excised hearts and cardiac images. Model error estimation will be performed and simulation results will be validated through comparison with experiment data. The achievements will be 1) the establishment of databases of biomechanical properties, geometries and FE models for analyzing minimally invasive mitral valve repair treatment;2) the candidate will gain extensive training and an in-depth understanding of the cardiovascular biomechanics, especially the mechanics related to heart valve disease.
This research is relevant to a minimally invasive treatment of mitral valve disease, in particular for high-risk patients who cannot undergo open-heart surgery. Findings of this study will offer insights for better device designs and valve disease treatments.
|Zuo, Keping; Pham, Thuy; Li, Kewei et al. (2016) Characterization of biomechanical properties of aged human and ovine mitral valve chordae tendineae. J Mech Behav Biomed Mater 62:607-618|
|Bhattacharya, Shamik; Pham, Thuy; He, Zhaoming et al. (2014) Tension to passively cinch the mitral annulus through coronary sinus access: an ex vivo study in ovine model. J Biomech 47:1382-8|
|Pham, Thuy; Sun, Wei (2014) Material properties of aged human mitral valve leaflets. J Biomed Mater Res A 102:2692-703|
|Pham, Thuy; Deherrera, Milton; Sun, Wei (2014) Finite element analysis of the biomechanical interaction between coronary sinus and proximal anchoring stent in coronary sinus annuloplasty. Comput Methods Biomech Biomed Engin 17:1617-29|
|Pham, Thuy; Sun, Wei (2012) Comparison of biaxial mechanical properties of coronary sinus tissues from porcine, ovine and aged human species. J Mech Behav Biomed Mater 6:21-9|
|Martin, Caitlin; Pham, Thuy; Sun, Wei (2011) Significant differences in the material properties between aged human and porcine aortic tissues. Eur J Cardiothorac Surg 40:28-34|
|Pham, Thuy; Sun, Wei (2010) Characterization of the mechanical properties of the coronary sinus for percutaneous transvenous mitral annuloplasty. Acta Biomater 6:4336-44|