Improving the repair or replacement of heart valves
Associate Professor of Surgery and Biomedical Engineering Karyn S. Kunzelman in collaboration with Dr. Pat Cochran, is studying the material properties of valves in both the healthy and diseased states in an effort to improve the repair and replacement of heart valves. Previously, material testing of heart valve tissue was performed in a single direction (uniaxial testing). This test involves pulling on the tissue and measuring the forces generated and the amount of deformation. However, uniaxial testing does not represent the loading conditions in a physiologic system, where the loads are applied in many directions. Biaxial tensile testing more accurately represents the physiologic stresses encountered in an active heart. An understanding of a tissue's biaxial behavior will help improve valve repair and tissue valve design. The focus of the biaxial project shown is to determine the material properties of healthy and diseased mitral and aortic valve tissue. The ultimate goal is to track how the properties change as the heart is exposed to increased stresses (from various forms of heart disease), and to determine better methods for repairing or replacing the valves.