Braided composite stent for peripheral vascular applications

Area of Science:

• Biomaterials Engineering
• Medical Device Design
• Computational Mechanics

Background:

• Braided composite stents (BCS) offer a hybrid design combining nitinol wires and polyethylene terephthalate (PET) strips.
• The mechanical properties of these novel stents require thorough investigation for clinical application.

Purpose of the Study:

• To systematically investigate the influence of key design factors on the mechanical performance of BCS.
• To provide guidance for optimizing BCS design to minimize complications.

Main Methods:

• Computational modeling was employed to study five design factors: nitinol wire number, braiding angle, nitinol wire diameter, PET strip thickness, and PET strip stiffness.
• Orthogonal experimental design was utilized for efficient quantitative analysis of factor sensitivity.

Main Results:

• Nitinol wire diameter and braiding angle were identified as the most critical factors for mechanical performance.
• Increased nitinol wire diameter enhanced radial strength but reduced flexibility.
• A larger braiding angle improved both radial strength and flexibility, though its impact diminished under large deformation.

Conclusions:

• The study elucidates the relationship between design parameters and mechanical behavior of BCS.
• Nitinol wire diameter and braiding angle are key determinants of stent performance.
• PET strip properties become more influential during large deformations, and PET strip count affects surface coverage, informing future stent optimization.