Biomechanics and Biomaterials Design Laboratory, School of Aerospace and Mechanical Engineering, The University of Oklahoma, Norman, Oklahoma, USA.
Computational Fluid-Structure Interaction Laboratory, Department of Mechanical Engineering, Iowa State University, Ames, Iowa, USA.
Int J Numer Method Biomed Eng. 2020 Jul;36(7):e3346. doi: 10.1002/cnm.3346. Epub 2020 May 8.
Current clinical assessment of functional tricuspid valve regurgitation relies on metrics quantified from medical imaging modalities. Although these clinical methodologies are generally successful, the lack of detailed information about the mechanical environment of the valve presents inherent challenges for assessing tricuspid valve regurgitation. In the present study, we have developed a finite element-based in silico model of one porcine tricuspid valve (TV) geometry to investigate how various pathological conditions affect the overall biomechanical function of the TV. There were three primary observations from our results. Firstly, the results of the papillary muscle (PM) displacement study scenario indicated more pronounced changes in the TV biomechanical function. Secondly, compared to uniform annulus dilation, nonuniform dilation scenario induced more evident changes in the von Mises stresses (83.8-125.3 kPa vs 65.1-84.0 kPa) and the Green-Lagrange strains (0.52-0.58 vs 0.47-0.53) for the three TV leaflets. Finally, results from the pulmonary hypertension study scenario showed opposite trends compared to the PM displacement and annulus dilation scenarios. Furthermore, various chordae rupture scenarios were simulated, and the results showed that the chordae tendineae attached to the TV anterior and septal leaflets may be more critical to proper TV function. This in silico modeling-based study has provided a deeper insight into the tricuspid valve pathologies that may be useful, with moderate extensions, for guiding clinical decisions. NOVELTY STATEMENT: The novelties of the research are summarized below: A comprehensive in silico pilot study of how isolated functional tricuspid regurgitation pathologies and ruptured chordae tendineae would alter the tricuspid valve function; An extensive analysis of the tricuspid valve function, including mechanical quantities (eg, the von Mises stress and the Green-Lagrange strain) and clinically-relevant geometry metrics (eg, the tenting area and the coaptation height); and A developed computational modeling pipeline that can be extended to evaluate patient-specific tricuspid valve geometries and enhance the current clinical diagnosis and treatment of tricuspid regurgitation.
目前,功能性三尖瓣反流的临床评估依赖于从医学成像模式中量化的指标。尽管这些临床方法通常是成功的,但由于缺乏有关瓣膜机械环境的详细信息,因此评估三尖瓣反流存在固有挑战。在本研究中,我们针对一个猪三尖瓣(TV)几何模型开发了一种基于有限元的计算模型,以研究各种病理条件如何影响 TV 的整体生物力学功能。我们的研究结果主要有三个观察结果。首先,乳头肌(PM)位移研究方案的结果表明,TV 生物力学功能的变化更为明显。其次,与均匀瓣环扩张相比,非均匀瓣环扩张方案会引起三个 TV 瓣叶的 von Mises 应力(83.8-125.3 kPa 与 65.1-84.0 kPa)和格林-拉格朗日应变(0.52-0.58 与 0.47-0.53)变化更为明显。最后,与 PM 位移和瓣环扩张方案相比,肺动脉高压研究方案的结果显示出相反的趋势。此外,还模拟了各种腱索断裂方案,结果表明,附着在 TV 前瓣和隔瓣上的腱索可能对 TV 的正常功能更为关键。这项基于计算模型的研究更深入地了解了三尖瓣病变,这些病变可能具有指导临床决策的作用。创新点:研究的创新点总结如下:全面研究孤立性功能性三尖瓣反流病变和断裂腱索如何改变三尖瓣功能的计算模型;对三尖瓣功能进行广泛分析,包括力学量(例如,von Mises 应力和格林-拉格朗日应变)和临床相关的几何度量(例如,帆状面积和对合高度);以及开发了一个计算模型管道,该管道可以扩展到评估特定于患者的三尖瓣几何形状,并增强当前对三尖瓣反流的临床诊断和治疗。