A mechanism for the size-related differences in mechanical properties of mitral valve chordae

Understanding the structure/function relationship of mitral valve chordae is important to mitral valve repair, chodral transposition and engineering of artificial chordae-like materials. The objectives of this study were to investigate the size-related variations in the mechanical properties of porcine mitral valve chordae, and explain these variations from their intrinsic microstructure. Based on quantification of collagen, water content, fibril crimp, and fibril ultrastructure, we conclude that collagen fiber crimp and collagen fibril packing are responsible for differences in chordal extensibility and modulus, respectively.