Advanced Manufacturing of Coil-Reinforced Multilayer Vascular Grafts to Optimize Biomechanical Performance

Area of Science:

• Biomaterials Engineering
• Medical Device Design
• Vascular Surgery

Background:

• Small diameter vascular grafts require a precise balance of biomechanical properties, including burst pressure, compliance, and kink resistance, for successful clinical application.
• Previous multilayer vascular graft designs achieved high compliance and burst pressure but lacked sufficient kink resistance.

Purpose of the Study:

• To enhance kink resistance in electrospun polyurethane vascular grafts using a 3D-printed polymeric coil.
• To investigate the structure-property relationships between coil parameters and graft biomechanics.
• To utilize finite element (FE) models to explore graft designs for improved compliance and kink resistance.

Main Methods:

• Fabrication of vascular grafts with integrated 3D-printed polymeric coils.
• Experimental testing to evaluate biomechanical properties: compliance, burst pressure, kink radius, and suture retention strength.
• Development and validation of FE models to simulate graft compliance and kink radius.

Main Results:

• The addition of a polymeric coil improved kink resistance but decreased graft compliance.
• A successful graft design achieved saphenous vein graft-like compliance and clinically relevant kink resistance.
• FE models showed good agreement with experimental compliance but over-predicted kink radius, while capturing key trends.

Conclusions:

• The combination of 3D printing and FE modeling provides a framework for optimizing vascular graft design.
• Further model-driven design iterations are necessary to achieve enhanced graft compliance while maintaining kink resistance.
• This approach paves the way for future advancements in designing high-performance vascular grafts.