Dynamic finite-strain modelling of the human left ventricle in health and disease using an immersed boundary-finite element method.
Dynamic finite-strain modelling of the human left ventricle in health and disease using an immersed boundary-finite element method.
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DOI：
10.1093/imamat/hxu029
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发表时间：
2014-10
影响因子：
1.2
通讯作者：
Luo X
中科院分区：
文献类型：
--
作者：
Gao H;Carrick D;Berry C;Griffith BE;Luo X
心脏生物力学的详细模型对于改善心脏病患者的干预措施以及患者风险分层和治疗计划都很重要。例如，心脏中的压力分布影响心脏重构，但目前还无法在患者中获得这种分布。心脏的生物力学模型提供了详细的三维变形、应力和应变场，可以补充传统的临床数据。在这项工作中，我们介绍了人类左心室（LV）的动态计算模型，该模型来源于健康受试者和心肌梗死（MI）患者的临床成像数据。这两种模型都包含了详细的基于不变量的心室肌被动弹性的正交各向异性描述，以及详细的心室肌主动张力产生的生物物理模型。这些本构模型是在一个动态模拟框架内使用的，该框架考虑了心室肌和血液的惯性，该框架基于浸入边界（IB）方法和结构力学的有限元描述。模型的几何形状基于心脏磁共振（CMR）非侵入性获得的数据。CMR成像数据也用于估计被动和主动本构模型的参数，确定这些参数，使模拟的舒张末期和收缩末期体积与CMR成像研究确定的相应体积一致。利用这些模型，我们模拟了左室从舒张末期到收缩期末期的动力学。我们的模拟结果被证明与受试者特异性cmr衍生的应变测量结果以及早期对人类LV菌株分布的临床研究非常一致。
Detailed models of the biomechanics of the heart are important both for developing improved interventions for patients with heart disease and also for patient risk stratification and treatment planning. For instance, stress distributions in the heart affect cardiac remodelling, but such distributions are not presently accessible in patients. Biomechanical models of the heart offer detailed three-dimensional deformation, stress and strain fields that can supplement conventional clinical data. In this work, we introduce dynamic computational models of the human left ventricle (LV) that are derived from clinical imaging data obtained from a healthy subject and from a patient with a myocardial infarction (MI). Both models incorporate a detailed invariant-based orthotropic description of the passive elasticity of the ventricular myocardium along with a detailed biophysical model of active tension generation in the ventricular muscle. These constitutive models are employed within a dynamic simulation framework that accounts for the inertia of the ventricular muscle and the blood that is based on an immersed boundary (IB) method with a finite element description of the structural mechanics. The geometry of the models is based on data obtained non-invasively by cardiac magnetic resonance (CMR). CMR imaging data are also used to estimate the parameters of the passive and active constitutive models, which are determined so that the simulated end-diastolic and end-systolic volumes agree with the corresponding volumes determined from the CMR imaging studies. Using these models, we simulate LV dynamics from enddiastole to end-systole. The results of our simulations are shown to be in good agreement with subject-specific CMR-derived strain measurements and also with earlier clinical studies on human LV strain distributions.