Lee Lik Chuan, Sundnes Joakim, Genet Martin, Wenk Jonathan F, Wall Samuel T
Department of Mechanical Engineering, Michigan State University, East Lansing, MI, USA.
Simula Research Laboratory, Oslo, Norway.
Biomech Model Mechanobiol. 2016 Aug;15(4):791-803. doi: 10.1007/s10237-015-0723-8. Epub 2015 Sep 16.
An emerging class of models has been developed in recent years to predict cardiac growth and remodeling (G&R). We recently developed a cardiac G&R constitutive model that predicts remodeling in response to elevated hemodynamics loading, and a subsequent reversal of the remodeling process when the loading is reduced. Here, we describe the integration of this G&R model to an existing strongly coupled electromechanical model of the heart. A separation of timescale between growth deformation and elastic deformation was invoked in this integrated electromechanical-growth heart model. To test our model, we applied the G&R scheme to simulate the effects of myocardial infarction in a realistic left ventricular (LV) geometry using the finite element method. We also simulate the effects of a novel therapy that is based on alteration of the infarct mechanical properties. We show that our proposed model is able to predict key features that are consistent with experiments. Specifically, we show that the presence of a non-contractile infarct leads to a dilation of the left ventricle that results in a rightward shift of the pressure volume loop. Our model also predicts that G&R is attenuated by a reduction in LV dilation when the infarct stiffness is increased.
近年来，已开发出一类新兴模型来预测心脏生长和重塑（G&R）。我们最近开发了一种心脏G&R本构模型，该模型可预测对升高的血流动力学负荷的重塑，以及负荷降低时重塑过程的后续逆转。在此，我们描述了将此G&R模型集成到现有的心脏强耦合机电模型中。在这个集成的机电-生长心脏模型中，生长变形和弹性变形之间的时间尺度被分开。为了测试我们的模型，我们应用G&R方案，使用有限元方法在逼真的左心室（LV）几何形状中模拟心肌梗死的影响。我们还模拟了基于梗死机械性能改变的新型治疗的效果。我们表明，我们提出的模型能够预测与实验一致的关键特征。具体而言，我们表明非收缩性梗死的存在会导致左心室扩张，从而导致压力-容积环向右移动。我们的模型还预测，当梗死硬度增加时，左心室扩张的减少会减弱G&R。
