Department of Mechanical Engineering, University of Zabol, Zabol, Iran.
Biological Fluid Mechanics Research Laboratory, Biomedical Engineering Faculty, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran.
Math Biosci. 2017 Dec;294:143-159. doi: 10.1016/j.mbs.2017.10.007. Epub 2017 Oct 26.
Understanding the effects of cardiac diseases on the heart's functionality which is the purpose of many biomedical researches, directly affects the diagnostic and therapeutic methods. Myocardial infarction (MI) is a common complication of cardiac ischemia, however, the impact of MI on the left ventricle (LV) flow patterns has not been widely considered by computational fluid dynamics studies thus far.
In this study, we present an insightful numerical method that creates an artificial MI on an image-based fluid-structure interactional model of normal LV to investigate its influence on the flow in comparison with the normal case. Seventeen different models were developed to evaluate the effects of location, percentage, myocardial material properties and dilation size of MI on the LV's performance, area strain, wall displacement, pressure-volume loop, wall shear stress and velocity field.
The results show that MI considerably changes blood flow features which are fully dependent on MI parameters. For the case of constant MI location, the effect of a decrease of infarcted myocardium stiffness, increase of dilation size and increase of MI percentage are mostly similar. Although the location differences of MI under other constant conditions have similar impact on the ejection fraction, they also lead to dissimilar variations in the LV flow pattern and other indicators.
The presented model showed a capable computational method for investigating various mechanical MI conditions with respect to cardiac flow pattern. The perspective of this model development seems to be an applicable tool for MI clinical diagnosis and prediction of complications related to MI.
了解心脏病对心脏功能的影响是许多生物医学研究的目的，这直接影响到诊断和治疗方法。心肌梗死（MI）是心脏缺血的常见并发症，然而，迄今为止，计算流体动力学研究还没有广泛考虑 MI 对左心室（LV）流动模式的影响。
在这项研究中，我们提出了一种有见地的数值方法，即在正常 LV 的基于图像的流固相互作用模型上创建人工 MI，以与正常情况相比研究其对流动的影响。开发了 17 个不同的模型来评估 MI 的位置、百分比、心肌材料特性和扩张大小对 LV 性能、面积应变、壁位移、压力-容积环、壁切应力和速度场的影响。
结果表明，MI 会极大地改变血流特征，这些特征完全取决于 MI 参数。对于 MI 位置不变的情况，梗死心肌刚度降低、扩张尺寸增大和 MI 百分比增大的效果大多相似。尽管在其他恒定条件下 MI 位置的差异对射血分数有相似的影响，但它们也会导致 LV 流动模式和其他指标的不同变化。
所提出的模型展示了一种针对心脏血流模式研究各种机械 MI 情况的有能力的计算方法。该模型开发的观点似乎是 MI 临床诊断和预测与 MI 相关并发症的一种适用工具。
