Effects of Aneurysm on the Mechanical Properties and Histologic Structure of Aortic Sinuses
Effects of Aneurysm on the Mechanical Properties and Histologic Structure of Aortic Sinuses
复制标题
DOI：
10.1016/j.athoracsur.2014.03.016
复制
发表时间：
2014-07-01
影响因子：
4.6
通讯作者：
Sokolis, Dimitrios P.
中科院分区：
文献类型：
--
作者：
Kritharis, Eleftherios P.;Iliopoulos, Dimitrios C.;Sokolis, Dimitrios P.
背景主动脉根部动脉瘤是相对罕见的，但其破裂是一个有害的事件，急性血流动力学损害和高死亡率，有很少的可用数据，其机械性能，虽然动脉瘤破裂时，血流动力学应力超过壁强度。本研究旨在通过检测动脉瘤对主动脉窦力学和结构特性的影响来填补这一空白。从16例窦瘤患者手术修复过程中和18例年龄匹配的非窦瘤尸检受试者中获得窦组织，并按年龄（年轻与老年）、区域（左与右与非冠状动脉）和方向（周向与纵向）分组。组织被提交给弹性蛋白/胶原蛋白含量的组织学评价和机械测试超出断裂的确定故障属性和材料表征的真菌型model.Results.对比方向依赖性（各向异性）材料常数和失效特性，以及健康窦中弹性蛋白/胶原纤维的主要周向增强，在动脉瘤性右冠状窦和左冠状窦中发现了近乎相似的（各向同性）特性和任意排列的纤维，以及动脉瘤性非冠状窦中较少的各向异性特性。在年轻和老年受试者中，鼻窦炎和健康鼻窦之间的变化相当。前者表现出显着更高的破坏应力，破坏拉伸，和峰值弹性模量，其增加的弹性蛋白/胶原蛋白含量的理由。我们提交的证据表明，与非扩张的健康鼻窦相比，鼻窦的各向同性组织力学特性更明显，这似乎与施加在鼻窦上的轴对称应力一致，因为鼻窦的形状更接近球形。(C)2014年由胸外科医师协会
Background. Aortic root aneurysms are relatively uncommon but their rupture is a detrimental event with acute hemodynamic compromise and high mortality, and there are few available data on their mechanical properties, although aneurysm rupture occurs when hemodynamic stresses exceed wall strength. This study aimed to fill this gap by examining the effect of aneurysm on the mechanical and structural properties of aortic sinuses.Methods. Sinus tissue was procured from 16 aneurysmal patients during surgical repair and from 18 age-matched nonaneurysmal autopsy subjects, and grouped by age (young versus old), region (left versus right versus noncoronary), and direction (circumferential versus longitudinal). The tissue was submitted to histologic evaluation of elastin/collagen contents and to mechanical testing beyond rupture for the determination of failure properties and material characterization by the Fung-type model.Results. Contrasting the direction-dependent (anisotropic) material constants and failure properties, and the primarily circumferential reinforcement of elastin/collagen fibers in healthy sinuses, near-similar (isotropic) properties and arbitrarily aligned fibers were found in the aneurysmal right and left coronary sinuses, together with less anisotropic properties in the aneurysmal noncoronary sinus. Variations between aneurysmal and healthy sinuses were comparable in young and old subjects. The former displayed significantly higher failure stress, failure stretch, and peak elastic modulus, justified by their increased elastin/collagen contents.Conclusions. We submit evidence of more isotropic histomechanical properties in the aneurysmal sinuses that seem consistent with the more axisymmetric stresses exerted on them owing to their more spherical shape, compared with the nondilated healthy sinuses that presented marked anisotropic properties. (C) 2014 by The Society of Thoracic Surgeons