Huang Xiao-Zhen, Wang Zhi-Yun, Dai Xiao-Hua, Zhang Mei
Qilu Hospital of Shandong University, Jinan, China.
Echocardiography. 2013 Feb;30(2):211-8. doi: 10.1111/echo.12005. Epub 2012 Oct 24.
Atherosclerotic plaque rupture is closely related to high regional mechanical stress in the plaque itself. We aimed to explore the longitudinal mechanical properties of upstream and downstream shoulders and fibrous cap tops of human atherosclerotic plaques in vivo by velocity vector imaging (VVI) combined with acoustic densitometry (AD) imaging.
We included 135 patients with carotid atherosclerotic plaque. VVI and AD were used to examine 3 regions of carotid plaque along the longitudinal-axis view. A total of 405 regions were classified with low or high AD values by corrected averages image intensity (AIIc%) < or ≥50, respectively. Peak systolic strain, strain rate (SR), and velocity were significantly greater for upstream than downstream shoulders and fibrous cap tops of carotid plaque (P < 0.05 for both). AIIc% was significantly lower for upstream than downstream plaque shoulders (P < 0.05). Peak systolic SR of the plaque regions was negatively correlated with corresponding AIIc% (R(2) = 0.499, P < 0.05).
The longitudinal strain of human carotid atherosclerotic plaques as derived by VVI is associated with its corresponding AD but also in part with the internal position of the strain, with values greater for upstream than downstream shoulders and fibrous cap tops.
动脉粥样硬化斑块破裂与斑块自身较高的局部机械应力密切相关。我们旨在通过速度向量成像（VVI）结合声学密度测定（AD）成像，在体内探索人类动脉粥样硬化斑块上游和下游肩部以及纤维帽顶部的纵向力学特性。
我们纳入了135例颈动脉粥样硬化斑块患者。采用VVI和AD沿颈动脉斑块的纵轴视图检查3个区域。根据校正平均图像强度（AIIc%）分别<或≥50，将总共405个区域分为低或高AD值。颈动脉斑块上游肩部的收缩期峰值应变、应变率（SR）和速度显著高于下游肩部和纤维帽顶部（两者P均<0.05）。斑块上游肩部的AIIc%显著低于下游肩部（P<0.05）。斑块区域的收缩期峰值SR与相应的AIIc%呈负相关（R² = 0.499，P<0.05）。
通过VVI得出的人类颈动脉粥样硬化斑块的纵向应变与其相应的AD相关，但也部分与应变的内部位置有关，上游肩部和纤维帽顶部的值大于下游。
