A numerical study on the application of the functionally graded materials in the stent design

Area of Science:

• Biomedical Engineering
• Materials Science
• Computational Mechanics

Background:

• Stent deformation can cause significant injury to blood vessels and atherosclerotic plaques.
• Minimizing undesirable stent deformation is crucial for improving patient outcomes.

Purpose of the Study:

• To investigate the efficacy of Functionally Graded Materials (FGM) in reducing undesirable stent deformation.
• To optimize stent design through tailored material properties for biomechanical performance.

Main Methods:

• Finite Element (FE) method was utilized to simulate stent expansion and plaque displacement.
• Simulations included three hyperelastic plaque models and five elastoplastic stent materials.
• Key metrics evaluated were dogboning, foreshortening, maximum plaque stress, and stent expansion pressure.

Main Results:

• All simulated FGMs exhibited reduced dogboning compared to uniform stents.
• The FGM with the lowest heterogeneous index demonstrated the least dogboning.
• Steel stents showed minimal foreshortening and expansion pressure, but dogboning reduction was more significant with FGMs.

Conclusions:

• Functionally Graded Materials show significant potential for minimizing stent deformation, particularly dogboning.
• An FGM with a heterogeneous index of 0.5 is predicted to yield optimal results.
• Tailoring FGM parameters offers a promising approach for biomechanical optimization in stent design.