Corti Mattia, Zingaro Alberto, Dede' Luca, Quarteroni Alfio Maria
MOX-Dipartimento di Matematica, Politecnico di Milano, Piazza Leonardo da Vinci 32, Milan, 20133, Italy.
MOX-Dipartimento di Matematica, Politecnico di Milano, Piazza Leonardo da Vinci 32, Milan, 20133, Italy.
Comput Biol Med. 2022 Nov;150:106143. doi: 10.1016/j.compbiomed.2022.106143. Epub 2022 Sep 21.
We analyse the haemodynamics of the left atrium, highlighting differences between healthy individuals and patients affected by atrial fibrillation. The computational study is based on patient-specific geometries of the left atria to simulate blood flow dynamics. We design a novel procedure to compute the boundary data for the 3D haemodynamic simulations, which are particularly useful in absence of data from clinical measurements. With this aim, we introduce a parametric definition of atrial displacement, and we use a closed-loop lumped parameter model of the whole cardiovascular circulation conveniently tuned on the basis of the patient's characteristics. We evaluate several fluid dynamics indicators for atrial haemodynamics, validating our numerical results in terms of clinical measurements; we investigate the impact of geometric and clinical characteristics on the risk of thrombosis. To highlight the correlation of thrombus formation with atrial fibrillation, according to medical evidence, we propose a novel indicator: age stasis. It arises from the combination of Eulerian and Lagrangian quantities. This indicator identifies regions where slow flow cannot properly rinse the chamber, accumulating stale blood particles, and creating optimal conditions for clots formation.
我们分析了左心房的血流动力学，突出了健康个体与受心房颤动影响患者之间的差异。该计算研究基于左心房的患者特异性几何结构来模拟血流动力学。我们设计了一种新颖的程序来计算三维血流动力学模拟的边界数据，这在缺乏临床测量数据时特别有用。为此，我们引入了心房位移的参数定义，并使用了一个基于患者特征方便调整的全心血管循环闭环集总参数模型。我们评估了心房血流动力学的几个流体动力学指标，并根据临床测量验证了我们的数值结果；我们研究了几何和临床特征对血栓形成风险的影响。为了突出血栓形成与心房颤动的相关性，根据医学证据，我们提出了一个新指标：年龄淤滞。它源于欧拉量和拉格朗日量的结合。该指标识别出缓慢血流无法适当冲洗心房腔、积聚陈旧血液颗粒并为血栓形成创造最佳条件的区域。
