Design–simulation–manufacturing–assessment framework for geometric optimization of polymeric heart valves toward enhanced durability
摘要
Owing to their excellent biocompatibility and potential for durability enhancement, polymeric heart valves (PHVs) are emerging as a promising alternative to traditional prostheses. Unlike conventional materials, PHVs can be manufactured under precise design criteria, enabling targeted performance improvements. This study introduces a geometric optimization strategy for enhancing the durability of PHVs. The finite element method (FEM) is combined with a dip-molding technique to develop a novel polymeric aortic valve with improved mechanical properties. The tri-leaflet geometry is parameterized using B-spline curves, and the maximum stress in the valve is reduced from 2.4802 to 1.7773 MPa using a multiobjective optimization algorithm NSGA-II (non-dominated sorting genetic algorithm II). Pre-optimized and optimized valve prototypes were fabricated via dip-molding and evaluated during pulsatile-flow tests and accelerated wear tests. The optimized design meets the ISO 5840 standards, with an effective orifice area of 2.019 cm2, a regurgitant fraction of 5.693%, and a transvalvular pressure gradient of 7.576 mmHg. Moreover, the optimized valve maintained its structural integrity and functionality over 14 million cycles of the accelerated wear test, whereas the unoptimized valve failed after two million cycles. These findings confirm that the FEM-based geometric optimization method enhances both the mechanical performance and durability of PHVs.