关于基本计算流体动力学对于左心房流量的强大可靠模型的重要性
Ehsan Khalili1, Cécile Daversin-Catty2, Andy L Olivares3
1Department of Computational Physiology, Simula Research Laboratory, Oslo, Norway.
概括
高分辨率的计算流体动力学 (CFD) 对于精确建模左心房 (LA) 流量至关重要. 目前的正常分辨率模拟显示出显著的变化和差的相关性,特别是在左心房附属体 (LAA).
科学领域:
- 心血管流体动力学心血管流体动力学
- 生物医学工程 生物医学工程
- 计算科学是一种计算科学.
背景情况:
- 关于左心房 (LA) 流量的计算流体动力学 (CFD) 研究是复杂的,将血动力学与心房联系起来.
- 然而,LA流动的基本流体建模方面需要进一步研究.
研究的目的:
- 在LA流动模拟中研究时空收.
- 为了比较高分辨率 (HR) 与正常分辨率 (NR) 的解决方案策略,用于LA血动力学和压力预测.
主要方法:
- 在12个患者特定的LA几何形状上进行了硬墙CFD模拟.
- 使用了第二阶准确的,以时空为中心的解决器.
- 对关键血液动力学参数进行了融合和HR与NR策略比较.
主要成果:
- 融合研究显示,在中间分辨率之间,时间平均壁切应力 (WSS),振荡切指数 (OSI),相对停留时间 (RRT) 和内皮细胞激活潜力 (ECAP) 的变化率为30-55%.
- HR与NR模拟显示,在LA中,WSS,RRT和ECAP的相关性很好,但OSI的相关性很差.
- 在左心房附属体 (LAA) 中,OSI,RRT和ECAP的相关性很差,只有WSS显示出良好的相关性.
结论:
- 需要显著的数值分辨率才能对心房血动力学和压力进行可靠的预测.
- 建议每周期大约有1000万个元素和1万个时间步骤,比通常使用的数量更高.
- 关注基本的数值方面对于开发可信,强大和可靠的LA流量模型至关重要.
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