Abstract 15923: Development of Self-Regenerative Heart Valves Based on Non-Degradable Scaffolding Approach
Objective: Despite early interesting results of tissue engineering of heart valves, there is still a need for patient-specific, self-regenerative heart valves. Most of the engineered tissues that were implanted in animals failed mainly because of limited durability and progressive regurgitation due to shrinkage of their degradable scaffolds. To overcome these limitations, we have developed self-regenerative heart valves comprised of a non-degradable ultra-flexible Nitinol scaffold enclosed by autologous cells. This approach promises the long-term durability along with improved biocompatibility and hemodynamics.
Methods: By using a 3D cell culture method, the Nitinol mesh scaffold is enclosed through cultured layers of cells similar to those observed in vivo. The layers consist of smooth muscle and fibroblasts/myofibroblasts to fulfill the role of valvular interestitial cells and a layer of endothelial cells as the outer lining. Cell-metal attachment for each leaflet was tested using a custom-made bioreactor capable of producing physiological flows. Finally, the tri-leaflet hybrid valves are tested in a heart flow simulator to test their functionality in a naturally simulated condition.
Results: The tests confirmed the proper compliance of the leaflets. The mesh-based leaflets open and clos suitably -similar to a natural heart valve- due to physiological ventricular pressure. The hybrid valve is found to operate properly even under the low flow rates (i.e., 2.5 L/min) exhibiting a comparable compliance to the natural heart valves. No tissue separation or decomposition of valve was observed during this experiment (Figure 1).
Conclusions: We have successfully developed and tested a hybrid self-regenerative heart valve that mimics the native valve’s biocompatibility and hemodynamics while maintaining adequate strength and long-term durability.
- © 2013 by American Heart Association, Inc.