The importance of the pericardium for cardiac biomechanics: from physiology to computational modeling
The importance of the pericardium for cardiac biomechanics: from physiology to computational modeling
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DOI：
10.1007/s10237-018-1098-4
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发表时间：
2019-04-01
影响因子：
3.5
通讯作者：
Wall, Wolfgang A.
中科院分区：
文献类型：
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作者：
Pfaller, Martin R.;Hoermann, Julia M.;Wall, Wolfgang A.
人的心脏被包裹在心包腔内。心包由一层薄囊组成，与心肌之间由一层薄薄的液体隔开。它提供了一种空间固定器和心肌的无摩擦滑动。心包的影响对于心脏的预测性机械模拟是必不可少的。然而，对于生理上正确的和计算上容易处理的心包边界条件，还没有达成共识。在这里，我们建议将心包的影响模拟为一个平行的弹簧和阻尼器，沿法线方向作用于心外膜。使用四腔几何模型，我们比较了有心包边界条件的模型和有固定心尖的模型。参数研究显示了心包僵硬的影响。将模拟结果与电影磁共振成像的测量结果进行比较，发现添加心包边界条件可以得到关于房室平面移位、心房充盈和总体空间近似误差的更好的近似。我们证明，这个简单的心包-心肌相互作用模型可以正确地预测心脏的泵血机制，正如先前临床研究所评估的那样。利用心包模型不仅可以提供更真实的心脏力学模拟，而且还可以对心包-心肌相互作用提供新的见解，这在临床测量中尚不能评估。
The human heart is enclosed in the pericardial cavity. The pericardium consists of a layered thin sac and is separated from the myocardium by a thin film of fluid. It provides a fixture in space and frictionless sliding of the myocardium. The influence of the pericardium is essential for predictive mechanical simulations of the heart. However, there is no consensus on physiologically correct and computationally tractable pericardial boundary conditions. Here, we propose to model the pericardial influence as a parallel spring and dashpot acting in normal direction to the epicardium. Using a four-chamber geometry, we compare a model with pericardial boundary conditions to a model with fixated apex. The influence of pericardial stiffness is demonstrated in a parametric study. Comparing simulation results to measurements from cine magnetic resonance imaging reveals that adding pericardial boundary conditions yields a better approximation with respect to atrioventricular plane displacement, atrial filling, and overall spatial approximation error. We demonstrate that this simple model of pericardial-myocardial interaction can correctly predict the pumping mechanisms of the heart as previously assessed in clinical studies. Utilizing a pericardial model not only can provide much more realistic cardiac mechanics simulations but also allows new insights into pericardial-myocardial interaction which cannot be assessed in clinical measurements yet.