Vascular Stent Analysis

It is important for cardiologist to understand the stresses and strains the stent experiences during deployment. We created a 3-D model of the coiled stent which is exported into ANSYS creating the finite element model. The stent material is Poly-L-Lactic Acid (PLLA) fiber with a Young's modulus of 7043(MPa) and a Poisson's ratio of 0.35. A nonlinear material analysis simulates the material behavior through plastic deformation during expansion from 1(atm) to 14(atm). The von Mises stresses, principal stresses, and principal strains are analyzed to determine the yielding of the PLLA fiber. Also, the effect of different material properties including Young's modulus, yield stress, yield strain is examined for the baseline case and three additional cases with Young's modulus of 4701, 3189, and 2266(MPa). The axial displacement values are increased to see any effect on the maximum shear stresses.
Finally, verification testing is performed to compare the experimental results to the simulation results.