Zhou Jingyuan, Li Yijing, Li Tao, Tian Xiaobao, Xiong Yan, Chen Yu
Department of Applied Mechanics, Sichuan University, Chengdu 610065, China.
College of Mechanical Engineering, Sichuan University, Chengdu 610065, China.
J Funct Biomater. 2023 Jun 1;14(6):309. doi: 10.3390/jfb14060309.
Polymeric heart valves (PHVs) are a promising and more affordable alternative to mechanical heart valves (MHVs) and bioprosthetic heart valves (BHVs). Materials with good durability and biocompatibility used for PHVs have always been the research focus in the field of prosthetic heart valves for many years, and leaflet thickness is a major design parameter for PHVs. The study aims to discuss the relationship between material properties and valve thickness, provided that the basic functions of PHVs are qualified. The fluid-structure interaction (FSI) approach was employed to obtain a more reliable solution of the effective orifice area (EOA), regurgitant fraction (RF), and stress and strain distribution of the valves with different thicknesses under three materials: Carbothane PC-3585A, xSIBS and SIBS-CNTs. This study demonstrates that the smaller elastic modulus of Carbothane PC-3585A allowed for a thicker valve (>0.3 mm) to be produced, while for materials with an elastic modulus higher than that of xSIBS (2.8 MPa), a thickness less than 0.2 mm would be a good attempt to meet the RF standard. What is more, when the elastic modulus is higher than 23.9 MPa, the thickness of the PHV is recommended to be 0.l-0.15 mm. Reducing the RF is one of the directions of PHV optimization in the future. Reducing the thickness and improving other design parameters are reliable means to reduce the RF for materials with high and low elastic modulus, respectively.
聚合物心脏瓣膜（PHV）是机械心脏瓣膜（MHV）和生物人工心脏瓣膜（BHV）一种有前景且更经济实惠的替代品。多年来，用于PHV的具有良好耐久性和生物相容性的材料一直是人工心脏瓣膜领域的研究重点，而瓣叶厚度是PHV的一个主要设计参数。该研究旨在探讨在PHV基本功能合格的前提下，材料性能与瓣膜厚度之间的关系。采用流固耦合（FSI）方法，以获得三种材料（Carbothane PC - 3585A、xSIBS和SIBS - CNTs）下不同厚度瓣膜的有效瓣口面积（EOA）、反流分数（RF）以及应力和应变分布的更可靠解决方案。本研究表明，Carbothane PC - 3585A较小的弹性模量使得能够制造出更厚的瓣膜（>0.3 mm），而对于弹性模量高于xSIBS（2.8 MPa）的材料，小于0.2 mm的厚度将是满足RF标准的一次良好尝试。此外，当弹性模量高于23.9 MPa时，建议PHV的厚度为0.1 - 0.15 mm。降低RF是未来PHV优化的方向之一。分别降低厚度和改善其他设计参数是降低高弹性模量和低弹性模量材料RF的可靠手段。
