The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Room 2119 U. A. Whitaker Building, 313 Ferst Drive, Atlanta, GA 30332-0535, USA.
Ann Biomed Eng. 2013 Jul;41(7):1331-46. doi: 10.1007/s10439-013-0785-7. Epub 2013 Mar 21.
The aortic valve (AV) experiences a complex mechanical environment, which includes tension, flexure, pressure, and shear stress forces due to blood flow during each cardiac cycle. This mechanical environment regulates AV tissue structure by constantly renewing and remodeling the phenotype. In vitro, ex vivo and in vivo studies have shown that pathological states such as hypertension and congenital defect like bicuspid AV (BAV) can potentially alter the AV's mechanical environment, triggering a cascade of remodeling, inflammation, and calcification activities in AV tissue. Alteration in mechanical environment is first sensed by the endothelium, which in turn induces changes in the extracellular matrix, and triggers cell differentiation and activation. However, the molecular mechanism of this process is not understood very well. Understanding these mechanisms is critical for advancing the development of effective medical based therapies. Recently, there have been some interesting studies on characterizing the hemodynamics associated with AV, especially in pathologies like BAV, using different experimental and numerical methods. Here, we review the current knowledge of the local AV mechanical environment and its effect on valve biology, focusing on in vitro and ex vivo approaches.
主动脉瓣（AV）经历着复杂的机械环境，包括在每个心动周期中由于血流产生的张力、弯曲、压力和切应力。这种机械环境通过不断更新和重塑表型来调节 AV 组织的结构。体外、离体和体内研究表明，高血压等病理状态和二叶式主动脉瓣（BAV）等先天性缺陷可能会改变 AV 的机械环境，引发 AV 组织中的一系列重塑、炎症和钙化活动。机械环境的改变首先被内皮细胞感知，内皮细胞继而引起细胞外基质的变化，并触发细胞分化和激活。然而，这个过程的分子机制还不是很清楚。了解这些机制对于推进有效的基于医学的治疗方法的发展至关重要。最近，已经有一些关于使用不同的实验和数值方法来描述与 AV 相关的血流动力学的有趣研究，尤其是在 BAV 等病理情况下。在这里，我们回顾了局部 AV 机械环境及其对瓣膜生物学影响的现有知识，重点介绍了体外和离体方法。
