Characterization of critical hemodynamics contributing to aneurysmal remodeling at the basilar terminus in a rabbit model.
Characterization of critical hemodynamics contributing to aneurysmal remodeling at the basilar terminus in a rabbit model.
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DOI：
10.1161/strokeaha.110.585992
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发表时间：
2010-08
期刊：
影响因子：
8.3
通讯作者：
Meng H
中科院分区：
文献类型：
--
作者：
Metaxa E;Tremmel M;Natarajan SK;Xiang J;Paluch RA;Mandelbaum M;Siddiqui AH;Kolega J;Mocco J;Meng H
在兔模型中，双侧颈总动脉（CCA）结扎引起的血流动力学损伤可诱导基底动脉末梢动脉瘤重构。为了描述引发这种重构的关键血流动力学特征，我们应用了一种新的血流动力学-组织学共作图技术。8只兔接受双侧CCA结扎以增加基底动脉流量。其中三人接受了假手术。计算流体动力学评估基底端血流动力学损伤。第5天采集分叉组织；组织学与结扎后壁剪应力（WSS）和壁剪应力梯度（WSSG）的初始血流动力学场共同绘制。所有分叉在暴露于高WSS和正WSSG加速流的尖周区域均表现出内部弹性层（IEL）损失。在WSS>122 Pa和WSSG>530 Pa/mm的位置，IEL损伤发生率为100%。破坏性重构的程度与血流动力学损伤的程度相关，包括IEL损失、内侧变薄和管腔膨出。当局部血流动力学力超过兔基底动脉末端的特定极限时，动脉瘤重构开始。高WSS和阳性WSSG的结合代表“危险的”血流动力学可能诱发动脉瘤重构。
Hemodynamic insult by bilateral common carotid artery (CCA) ligation has been shown to induce aneurysmal remodeling at the basilar terminus in a rabbit model. To characterize critical hemodynamics that initiate this remodeling, we applied a novel hemodynamics-histology co-mapping technique. Eight rabbits received bilateral CCA ligation to increase basilar artery flow. Three underwent sham operations. Hemodynamic insult at the basilar terminus was assessed by computational fluid dynamics. Bifurcation tissue was harvested on day 5; histology was co-mapped with initial postligation hemodynamic fields of wall shear stress (WSS) and WSS gradient (WSSG). All bifurcations showed internal elastic lamina (IEL) loss in periapical regions exposed to accelerating flow with high WSS and positive WSSG. IEL damage happened 100% of the time at locations where WSS>122 Pa and WSSG>530 Pa/mm. The degree of destructive remodeling accounting for IEL loss, medial thinning, and luminal bulging correlated with the magnitude of the hemodynamic insult. Aneurysmal remodeling initiates when local hemodynamic forces exceed specific limits at the rabbit basilar terminus. A combination of high WSS and positive WSSG represents “dangerous” hemodynamics likely to induce aneurysmal remodeling.