Trinity Centre for Biomedical Engineering, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland.
Department of Mechanical, Manufacturing & Biomedical Engineering, School of Engineering, Trinity College Dublin, Dublin 2, Ireland.
Ann Biomed Eng. 2021 Mar;49(3):1022-1032. doi: 10.1007/s10439-020-02644-4. Epub 2020 Oct 15.
Bioprosthetic heart valves (BHVs) are implanted in aortic valve stenosis patients to replace the native, dysfunctional valve. Yet, the long-term performance of the glutaraldehyde-fixed bovine pericardium (GLBP) leaflets is known to reduce device durability. The aim of this study was to investigate a type of commercial-grade GLBP which has been over-looked in the literature to date; that of high collagen fibre dispersion (HD). Under uniaxial cyclic loading conditions, it was observed that the fatigue behaviour of HD GLBP was substantially equivalent to GLBP in which the fibres are highly aligned along the loading direction. It was also found that HD GLBP had a statistically significant 9.5% higher collagen content when compared to GLBP with highly aligned collagen fibres. The variability in diseased BHV delivery sites results in unpredictable and complex loading patterns across leaflets in vivo. This study presents the possibility of a shift from the traditional choice of circumferentially aligned GLBP leaflets, to that of high fibre dispersion arrangements. Characterised by its high fatigue life and increased collagen content, in addition to multiple fibre orientations, GLBP of high fibre dispersion may provide better patient outcomes under the multi-directional loading to which BHV leaflets are subjected in vivo.
生物瓣(BHV)被植入主动脉瓣狭窄患者体内,以替代功能失调的原生瓣膜。然而,戊二醛固定牛心包(GLBP)瓣叶的长期性能众所周知会降低装置的耐久性。本研究旨在研究一种迄今在文献中被忽视的商业级 GLBP,即具有高胶原纤维分散性(HD)的 GLBP。在单向循环加载条件下,观察到 HD GLBP 的疲劳行为与纤维沿加载方向高度排列的 GLBP 基本相当。还发现,与胶原纤维高度排列的 GLBP 相比,HD GLBP 的胶原含量统计学上显著高出 9.5%。病变 BHV 输送部位的可变性导致体内瓣叶上的负载模式不可预测且复杂。本研究提出了从传统的环形排列 GLBP 瓣叶选择转变为高纤维分散排列的可能性。具有高疲劳寿命和增加的胶原含量,以及多个纤维方向,高纤维分散的 GLBP 可能为 BHV 瓣叶在体内承受的多向负载提供更好的患者结果。