Development of Magnesium Alloy Scaffolds to Support Biological Myocardial Grafts: A Finite Element Investigation
Lesioned myocardial tissue can be replaced with innovative biological grafts. However, the strength of most biological grafts is initially not sufficient for left ventricular applications. Implants that mechanically support these grafts and gradually lose their function as the graft develops its strength are a possible solution. We are developing magnesium alloy scaffolds for this purpose. The finite element method was used to perform simulations wherein scaffolds are deformed according to the heart movement. This allows us to identify highly stressed regions within the implant that need design changes. Preformed scaffolds were determined to have significantly lower stresses in comparison to flat ones. The method of tensile triangles suggests shape changes for notable stress reduction. Furthermore, new scaffold shapes were developed and simulated. Two of them are recommended for further examinations through in vitro and in vivo tests. A completely new alternative scaffold concept is also proposed.
KeywordsNumerical simulation FEM Tensile triangles LA63 Left ventricle Heart attack Tissue substitution Supporting structure
The authors are thankful to the German Research Foundation (DFG) for their financial support. This project is funded within the Collaborative Research Center 599 (SFB 599) and the International Research Training Group 1627 (GRK 1627). Furthermore, we thank Martina Baldrich who developed scaffold shape 7 and Julian Schrader who developed shapes 8–12 in student projects, respectively.
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