Mechanical performance of self-expandable nitinol stent with lesion-specific design

This paper aims to assess the performance of a self-expandable nitinol stent, with lesion-specific design, using a finite-element (FE) method. A superelastic model was adopted to describe the superelasticity of nitinol. Hyperelastic models with damage, calibrated against experimental results, were used to describe the stress-stretch responses of arterial layers and plaque. Abaqus CAE was used to create FE models for a femoral artery with non-uniform diffusive stenosis and a nitinol stent with a lesion-specific design. In numerical simulations, an elastic tube was used to crimp and release the self-expandable stent in the diseased artery. The effect of this lesion-specific design on lumen gain was investigated by employing FE results for a commercial stent with a uniform design as a reference. The obtained results showed that the lesion-specific stent achieved larger lumen area in the artery with diffusive lesions.