The heart grows in response to changes in hemodynamic loading during normal development and in response to valve disease, hypertension, and other pathologies. In general, a left ventricle subjected to increased afterload (pressure overloading) exhibits concentric growth characterized by thickening of individual myocytes and the heart wall, while one experiencing increased preload (volume overloading) exhibits eccentric growth characterized by lengthening of myocytes and dilation of the cavity. Predictive models of cardiac growth could be important tools in evaluating treatments, guiding clinical decision making, and designing novel therapies for a range of diseases. Thus, in the past 20 years there has been considerable effort to simulate growth within the left ventricle. While a number of published equations or systems of equations (often termed “growth laws”) can capture some aspects of experimentally observed growth patterns, no direct comparisons of the various published models have been performed. Here we examine eight of these laws and compare them in a simple test-bed in which we imposed stretches measured during in vivo pressure and volume overload. Laws were compared based on their ability to predict experimentally measured patterns of growth in the myocardial fiber and radial directions as well as the ratio of fiber-to-radial growth. Three of the eight laws were able to reproduce most key aspects of growth following both pressure and volume overload. Although these three growth laws utilized different approaches to predict hypertrophy, they all employed multiple inputs that were weakly correlated during in vivo overload and therefore provided independent information about mechanics.

中文翻译：

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心肌肥厚现象学生长规律的比较

心脏随着正常发育过程中血流动力学负荷的变化以及瓣膜疾病、高血压和其他病理变化而生长。一般来说，后负荷增加（压力超载）的左心室表现出以单个肌细胞和心壁增厚为特征的同心生长，而经历前负荷增加（容量超负荷）的左心室表现出以肌细胞延长和腔扩张为特征的离心生长. 心脏生长的预测模型可能是评估治疗、指导临床决策和设计针对一系列疾病的新疗法的重要工具。因此，在过去的 20 年中，已经做出了相当大的努力来模拟左心室内的生长。虽然许多已发表的方程或方程组（通常称为“生长定律”）可以捕捉实验观察到的生长模式的某些方面，但尚未对各种已发表的模型进行直接比较。在这里，我们检查了其中的八项定律，并在一个简单的试验台中对它们进行了比较，在该试验台中，我们施加了在体内压力和容量超负荷期间测量的拉伸。根据它们预测实验测量的心肌纤维和径向生长模式以及纤维与径向生长的比率的能力，比较了这些定律。八项定律​​中的三项能够在压力和容量超载后重现增长的大多数关键方面。尽管这三个生长定律使用了不同的方法来预测肥大，