通过流体结构相互作用模拟,通过手术和透气导管大动脉替换引起的血液动力学变化的分析
Anna Maria Tango1, Alessandra Monteleone2, Andrea Ducci1
1UCL Mechanical Engineering, University College London, UK.
Computers in biology and medicine
|January 14, 2025
概括
手术和透气管大动脉置换改变了血液流动的动态. 过导管显示性能有所改善,但既不能完全恢复本源的功能,也不能防止血液停滞.
科学领域:
- 心血管工程 心血管工程
- 生物医学流体动力学
- 假体门的设计
背景情况:
- 动脉置换 (AVR) 程序,包括手术和透导管方法,是常见的,但可能导致由于血液动力学变化的并发症.
- 现有的假体门可能无法完全复制健康的主动脉的生理功能.
研究的目的:
- 通过先进的模拟,分析和比较手术和透气管AVRs的流体动力学与理想的本源大动脉.
- 调查当前AVR治疗对大动脉功能的影响,并确定治疗改进的领域.
主要方法:
- 使用LS-DYNA进行了流体结构相互作用 (FSI) 模拟,将拉格朗日 (结构) 和欧勒尔 (流体) 方法与混合任意-拉格朗日-欧勒尔算法相结合.
- 采用了理想化的大动脉根和叶片几何形状,大动脉壁被建模为线性弹性,叶片为超弹性 (奥格登模型).
- 应用了生理流量和压力条件来模拟整个心脏周期.
主要成果:
- 与手术相比,通过导管的动脉替换显示出更好的性能指标 (更大的有效孔径面积,更低的压力下降).
- 虽然透导管装置接近本源的性能,但它们显著改变了瓦萨尔瓦鼻的流动动力学,增加了血液静止和潜在的损伤.
- 两种假肢溶液都没有完全恢复原生门的血液动力学或打开行为.
结论:
- 目前的假体大动脉,特别是它们的设计,不能完全复制本源的生理条件.
- 透导管大动脉替换提供了比手术选择更好的血液动力性能,但需要进一步优化以减轻血液静止等风险.
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