Taghizadeh Hadi, Tafazzoli-Shadpour Mohammad, Shadmehr Mohammad B
Cardiovascular Engineering Lab, Faculty of Biomedical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran.
Cardiovascular Engineering Lab, Faculty of Biomedical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran.
J Am Soc Hypertens. 2015 Sep;9(9):735-44. doi: 10.1016/j.jash.2015.07.014. Epub 2015 Jul 31.
Arterial wall remodels its geometry and mechanical properties in response to hypertension to maintain functionality. The elevated pressure is sensed through cellular mechanotransduction pathways, and extra extracellular matrix is synthesized, leading to thickening and stiffening. The present study enquires the response of aortic lamellar structure to hypertensive blood pressure regarding unchanged circumferential stress "profile" across the media as remodeling criterion. We tested the hypothesis that alterations in the thickness of structural layers contributes to maintain stress profile with least deviation from normotensive conditions. To test this notion, finite element analysis was recruited to evaluate stress profile, considering wall residual stress, and lamellar structure was adjusted through an optimization algorithm. Our results indicated 47% increased thickness of the aortic media that originates from nonhomogenous thickening of the microstructural units. The thickening and stiffening responses of the wall tissue were coupled, and the optimized pattern of hypertension-induced remodeling was established.
动脉壁会响应高血压重塑其几何形状和力学性能,以维持功能。升高的压力通过细胞机械转导途径被感知,进而合成额外的细胞外基质,导致增厚和变硬。本研究以整个中膜圆周应力“分布”不变作为重塑标准,探究主动脉层状结构对高血压血压的反应。我们检验了这样一个假设,即结构层厚度的改变有助于维持应力分布,且与正常血压条件下的偏差最小。为验证这一观点,我们采用有限元分析来评估应力分布,同时考虑壁残余应力,并通过优化算法调整层状结构。我们的结果表明,主动脉中膜厚度增加了47%,这源于微观结构单元的非均匀增厚。壁组织的增厚和变硬反应是相互关联的,并且建立了高血压诱导重塑的优化模式。