Geometric Optimization of Polymeric Heart Valves Shows Breakthrough in Durability

Heart valve disease affects millions worldwide, often requiring surgical replacement with mechanical or biological prostheses. While life-saving, these traditional solutions come with limitations—mechanical valves demand lifelong anticoagulation therapy, and biological valves are prone to degeneration. Now, polymeric heart valves (PHVs) are emerging as a promising third option, combining biocompatibility, manufacturability, and the potential for enhanced durability.

In a new study published in Bio-Design and Manufacturing, researchers from Fudan University have demonstrated how geometric optimization, powered by finite element simulations and advanced dip-molding fabrication, can significantly improve the durability and performance of PHVs.

Smarter Design Through Simulation

The team designed a tri-leaflet polymeric aortic valve using B-spline curves to precisely parameterize its geometry. By applying the non-dominated sorting genetic algorithm II (NSGA-II), they minimized stress concentration in the valve leaflets—a critical factor influencing long-term durability.

This approach reduced maximum stress in the valve from 2.48 MPa to 1.77 MPa, while maintaining strong mechanical performance and fluid dynamics.

Putting Valves to the Test

Both pre-optimized and optimized valves were fabricated using a custom dip-molding process. The prototypes were evaluated under pulsatile-flow conditions and accelerated wear tests in compliance with ISO 5840 standards.

The results were striking:

Effective orifice area (EOA): 2.019 cm² (exceeding ISO minimum requirements)
Regurgitant fraction: Reduced by 65%, from 16.3% to just 5.7%
Durability: Optimized valves withstood 14 million cycles in accelerated wear tests, compared to only 2 million for unoptimized versions

Toward Clinical Translation

These findings highlight that geometry, not just material choice, plays a decisive role in heart valve performance. By optimizing valve curvature and leaflet design, researchers extended the functional lifespan and reduced stress-induced damage.

“Excessive stress concentrations can tear valve leaflets,” the authors note. “By redistributing stress more evenly across the surface, our optimized design demonstrates significantly improved durability.”

The Future of Polymeric Valves

While current results are based on in vitro testing, the study sets a strong foundation for the clinical development of PHVs. The next steps will involve adapting the optimization framework to different heart valve types and sizes, integrating fluid–structure simulations, and potentially incorporating machine learning for faster design cycles.

If successful, polymeric heart valves could usher in a new era of cardiovascular implants—offering longer-lasting, biocompatible, and cost-effective alternatives for patients worldwide.

Reference

Xu, T., Zhu, Z., Cai, Y., Chen, S., Guo, J., & Wang, S. (2025). Design–simulation–manufacturing–assessment framework for geometric optimization of polymeric heart valves toward enhanced durability. Bio-Design and Manufacturing, 1-12. https://doi.org/10.1631/bdm.2500046