Morphological and stent design risk factors to prevent migration phenomena for a thoracic aneurysm: A numerical analysis

The simulation results show that PASL > 18 mm is a crucial factor to prevent migration at a neck angle of 60°, and the smoothest contact condition with low friction coefficient (μ = 0.05). The increase in O% ranging from 10% to 20% improved the fixation strength. However, O% ≥ 25% at 60° caused eccentric deformation and stent collapse. Higher coefficient of friction μ > 0.01 considerably increased the migration risk when PASL = 18 mm. No migration was found in an idealized aorta model with a neck angle of 0°, PASL = 18 mm and μ = 0.05. Our results suggest carefully considering the stent length and oversizing value in this neck morphology to strengthen the contact and prevent migration.