FE-DOE: Finite element informed design of experiments to optimise bioinspired melt electrowritten (MEW) polymeric heart valves

Aortic stenosis is predominantly treated through transcatheter bioprosthetic heart valve implantation. The materials used in these devices, however, suffer from premature failure. Polymer heart valves have the potential to improve current commercial devices, offering materials with extended durability and customisation through fibre-reinforcement. Due to the wide range of available materials and structures, there is a need for a methodical approach to the design and optimisation of novel, bioinspired polymeric leaflets. This work presents a framework using FE and DOE tools to enable the creation of optimised bioinspired, 3D-printed, fibre-reinforced polymer leaflets using MEW. Here, FE models are created to represent MEW fibre-reinforced polymer leaflets for application in a transcatheter aortic heart valve. The behaviour of this valve under physiological loading conditions is modelled to predict valve performance and leaflet material response. These models were first used to investigate the impact of fibre orientation on valve performance and leaflet response, showing the benefit of using a bioinspired fibre reinforcement structure. Using DOE, the structural combination of MEW fibre-reinforcement and elastomeric matrix was optimised based on valve performance and leaflet stress and strain. Overall, the framework offers an efficient and versatile methodology for optimising fibre-reinforced polymer leaflets by utilising an in-silico approach to remove the need for manufacturing and testing of these devices.