title: The structure and mechanical properties of the mitral valve leaflet-strut chordae transition zone.
abstract: Biaxial testing, histological measurements and theoretical continuum mechanics modeling were employed to investigate the structure and mechanical properties of the mitral valve leaflet-strut chordae transition zone (LCT). The results showed that geometry changes and collagen fiber angle distribution contribute to variations in mechanical properties in the LCT zone. A simple three-coefficient exponential constitutive law was able to simulate the variation in stress-stretch behavior in the LCT zone by spatially varying a single coefficient and incorporating collagen fiber angle and degree of alignment. This quantitative information can greatly improve the predictions from biomechanical valve models by incorporating regional variations of structure and properties in the mitral leaflet-chordae tendineae system. These data provide the foundation for a computational model for studying stress distributions before and following chordal rupture, which may indicate the underlying reasons for the development of valve insufficiency in patients.
authors.affiliation: Department of Mechanical Engineering, San Diego State University, San Diego, CA 92182-1323, USA. lchen@kahuna.sdsu.edu
authors.forename: Ling
authors.initials: L
authors.lastname: Chen
authors.forename: Frank C
authors.initials: FC
authors.lastname: Yin
authors.forename: Karen
authors.initials: K
authors.lastname: May-Newman
mesh_terms: D000818:Animals; D016880:Anisotropy; D001696:Biomechanical Phenomena / Q000379:methods; D002815:Chordae Tendineae / Q000166:cytology* / Q000502:physiology*; D003094:Collagen / Q000502:physiology* / Q000648:ultrastructure*; D003198:Computer Simulation; D046508:Culture Techniques; D004548:Elasticity; D008943:Mitral Valve / Q000166:cytology* / Q000502:physiology*; D008955:Models, Cardiovascular; D011487:Protein Conformation; D013314:Stress, Mechanical; D013329:Structure-Activity Relationship; D013552:Swine
chemical_list: D003094:Collagen