Finite element analysis of mechanical strain to clarify the location of calcification for Jellyfish valve

In order to examine the mechanism of calcification which thought to be one of the major factors to deteriorate the durability of Jellyfish valve, the strain acting on valve membrane at its closed position under the static pressure was analyzed using finite element method(FEM), focusing on charges in mechanical characteristics. Material properties of valve membrane were obtained from the uniaxial tensile test, and the static pressure was 90 mmHg which denoted physiological mean aortic pressure. Using isoparametric membrane element with four nodes, FEM analysis was performed on the one- twelfth model of Jellyfish valve taking symmetry of valve shape into consideration. The result exhibited that strain concentration was observed at two areas. Then, in order to examine the strain distribution toward membrane thickness-wide direction, analysis was performed on the simplified model using isoparametric hexahedron element with eight nodes. The results exhibited that high tensile strain areas by analysis were corresponding to the locations of calcification in the animal trial. Based upon the results above, it was clarified that high tensile strain would have a major role to increase a calcification.