VISCOELASTIC BEHAVIOR OF HEART VALVE TISSUES UNDER BIAXIAL STRETCH

摘要

Recent in-vitro studies have demonstrated the peak strain rates of the anterior leaflet of the mitral valve (MV) to be between 500-1000%/s. Quantification of the MV biaxial mechanical behavior is a critical step in the development of a comprehensive constitutive model to predict in-vivo stresses from in-vitro or in-vivo strain data. However, previously reported biaxial testing methods have been limited to quasi-static strain rates on the order of 10%/s or less, which is insufficient to quantify the MV visco-elastic behavior. In order to address these issues, a novel high-speed biaxial stretching device was developed. This new device was used to fully characterize the biaxial mechanical properties of the anterior leaflet of the MV at physiological strain rates.