Development of a tissue engineered heart valve

Heart valves assist the body in efficiently moving blood throughout the circulatory system. Sometimes these valves become diseased and need to be replaced. Currently, the choice of heart valves is limited to two types: mechanical and bioprosthetic. However, both types of valves can suddenly fail due to degraded components, and can cause other post-surgical complications requiring further treatment. Heart valves made of living tissue would improve the durability of the implant and the options available to patients facing this surgery. It was the specific objective of this research to fabricate a biologic scaffold material by digesting the resident cells from viable pericardium. With the biologic scaffold for living valves being made from human pericardium, this tissue was compared to bovine pericardium.; Tissue viability was confirmed by culturing pericardial cells from the fresh tissue upon delivery of the tissue specimens to the laboratory. Fibulin-1, a protein in heart valves or blood vessels, was studied using immunoblots of protein samples from the intact pericardium. Histology of intact human pericardium was compared to biologic scaffolds created by digesting the resident cells. The mechanical properties of the intact tissue were contrasted with biologic scaffolds.; The scaffold creation was done in a manner to conserve the collagen and elastin fibers found in intact pericardium. The Young's modulus was significantly different (p < 0.05) for all biomaterials except between de-cellularized bovine and intact human pericardium. When comparing the ultimate tensile strength for the four biomaterials, all were significantly different. An interesting finding was that fibulin-1 was detected in intact pericardium from bovine and human sources.; From this study it was concluded that a biologic scaffold can be successfully made from pericardium. A scaffold made from unfixed tissue would leave histological features unaffected and would provide more desirable mechanical properties. These scaffolds would be appropriate to fabricate into valve leaflets and may have applicability in other tissue engineering applications.