A computational optimization study of a self-expandable transcatheter aortic valve

Area of Science:

• Biomedical Engineering
• Materials Science
• Mechanical Engineering

Background:

• Transcatheter aortic valve (TAV) stent design requires optimization beyond current clinical and leaflet focus.
• Existing peripheral stent optimization studies do not fully address unique TAV functional requirements.
• Nickel-Titanium (Ni-Ti) alloy is a common material for TAV stents, necessitating design improvements.

Purpose of the Study:

• To develop a cost-effective optimization framework for TAV stent design.
• To identify optimal TAV stent configurations by minimizing maximum strain during crimping.
• To investigate the influence of geometric parameters on TAV stent performance.

Main Methods:

• Utilized a simplified stent model to reduce computational cost during optimization.
• Investigated the impact of strut cross-section (width, thickness) and repeating unit geometry (cell size) on maximum strain.
• Employed 3D simulations to validate the simplified model and calculated radial force for further evaluation.

Main Results:

• The number of repeating units (cells) and strut width significantly influence maximum strain in TAV stents.
• A simplified modeling approach demonstrated less than 5% difference in maximum strain compared to 3D simulations.
• The developed framework provides a reliable method for TAV stent design improvement.

Conclusions:

• The proposed framework offers a simple, cost-effective, and reliable procedure for optimizing TAV stent designs.
• Geometric parameters like cell number and strut width are critical for managing strain in TAV stents.
• The validated simplified modeling strategy enhances the efficiency of TAV stent design optimization.