Strain Energy Minimization Technique to Design a Surgical Heart Valve Using a Novel Polymer

The natural aortic heart valve exhibits an exceptional balance of durability and efficiency, enabling over two billion cycles during a human lifespan. Designing a prosthetic valve that replicates these attributes presents significant challenges. The development of polymeric heart valves offers a promising alternative to existing biologic and mechanical options, aiming to improve durability and hemodynamic performance. This study focuses on the optimized design of the Foldax TRIA polymeric heart valve, leveraging computational modeling to minimize strain energy and enhance structural integrity.

A fully three-dimensional computational model of the TRIA valve was developed using LS-Dyna to simulate its behavior across a full cardiac cycle and optimize for fully open and fully closed configurations. The model incorporated an explicit finite element formulation without symmetry constraints, ensuring accurate representation of valve dynamics. The leaflets, composed of LifePolymer™ (a proprietary silicone urethane-urea), and the frame, made from Solvay Zeniva® PEEK, were analyzed for strain energy distribution. A perturbation analysis was conducted by varying leaflet width to assess its impact on strain distribution, durability, and kinematic efficiency. Additionally, hydrodynamic performance was evaluated using a pulse duplicator system.

The computational analysis identified an optimal leaflet width that minimized strain energy and provided uniform stress distribution, reducing the potential for long-term material fatigue. Leaflets that deviated from this optimal width exhibited excessive strain at critical points, leading to potential durability concerns. Hydrodynamic testing demonstrated that the TRIA valve exhibited a low pressure gradient and an efficient equivalent orifice area (EOA) compared to a leading bioprosthetic control valve. Long-term durability testing indicated stable valve performance over 600 million cycles, equivalent to nearly 20 years of use.

The optimized design of the Foldax TRIA polymeric heart valve successfully minimizes strain energy while maximizing hydrodynamic efficiency. Computational and experimental results suggest that this novel polymeric valve provides a viable, long-lasting alternative to traditional heart valve prostheses. Future studies should focus on in vivo validation to further establish clinical efficacy and longevity.