小鼠冠状动脉粥样硬化斑块的易损性与其下游支配区域心肌灌注和心肌应变的关系探讨  

The relationship between vulnerability of coronary atherosclerotic plaque and downstream myocardial perfusion and myocardial strain in mice

作　　者：黄凌霙 邓又斌[1] 刘娅妮 王译斌 田洁 王佳玉 孙睿颖 Huang Lingying;Deng Youbin;Liu Yani;Wang Yibin;Tian Jie;Wang Jiayu;Sun Ruiying(Department of Medical Ultrasound,Tongji Hospital,Huazhong University of Science and Technology,Wuhan 430030,China)

机构地区：[1]华中科技大学同济医学院附属同济医院超声影像科,武汉430030

出　　处：《中华超声影像学杂志》2021年第3期259-265,共7页Chinese Journal of Ultrasonography

基　　金：国家自然科学基金 (81571695)。

摘　　要：目的探讨小鼠冠状动脉斑块的易损性与其下游支配区域心肌灌注和心肌应变的关系。方法应用Vevo2100型高分辨小动物超声仪分别对13只冠状动脉具有稳定斑块的ApoE基因敲除小鼠(稳定斑块组)、13只冠状动脉具有易损斑块的ApoE基因敲除小鼠(易损斑块组)及15只性别、周龄相匹配的具有相同遗传背景的C57BL/6小鼠(对照组)行超声心动图检查。用心肌造影超声心动图(MCE)联合腺苷负荷实验对小鼠局部心肌灌注进行量化评估。根据拟合曲线计算上升期造影剂强度随时间变化的斜率(β)和平台期造影剂的峰值强度(A)。局部心肌血流量(MBF)等于A值与β值的乘积。用斑点追踪显像技术联合腺苷负荷试验对小鼠左室心肌纵向应变进行评估。斑块的易损性将通过组织病理学在左冠状动脉的连续组织切片中评估。结果稳定斑块组、易损斑块组、对照组小鼠的体重、心率、左心室舒张末期容积、左心室收缩末期容积、左心室质量及左室射血分数差异无统计学意义(均P>0.05)。稳定斑块组与易损斑块组血清三酰甘油、总胆固醇、高密度脂蛋白及低密度脂蛋白水平高于对照组(均P<0.05)。病理结果显示稳定斑块组与易损斑块组小鼠冠状动脉管腔狭窄率分别为(74.3±4.9)%、(75.5±7.1)%,差异无统计学意义(P>0.05)。稳定斑块组与易损斑块组在静息及腺苷负荷状态下,左心室前间隔中段以及后壁中段MBF值明显低于对照组(均P<0.05)。静息状态下稳定斑块组与易损斑块组MBF值差异无统计学意义(P>0.05)。腺苷负荷状态下易损斑块组MBF值明显低于稳定斑块组(P<0.05)。静息状态下,稳定斑块组与易损斑块组左室纵向应变较对照组降低,但差异无统计学意义(P>0.05)。腺苷负荷状态下,稳定斑块组与易损斑块组纵向应变较对照组明显下降(均P<0.05),且易损斑块组纵向应变较稳定斑块组也明显降低(P<0.05)。结�Objective To investigate the relationship between vulnerability of mouse coronary artery plaque and downstream myocardial perfusion and myocardial strain.Methods Thirteen ApoE knockout mice with stable coronary plaques(stable plaque group)and 13 ApoE knockout mice with vulnerable coronary plaques(vulnerable plaque group)were selected as the experimental group,and 15 sex-and age-matched C57BL/6 mice with the same genetic background as ApoE mice were chosed as the control group.Myocardial contrast echocardiography(MCE)was carried out to quantify regional myocardial perfusion at rest and during adenosine stress using a Vevo 2100 system(Visual sonics).Replenishment curves of myocardial contrast were obtained,and rates of signal rise(β)and plateau intensity(A)were recorded.MBF was estimated by the product of A andβ.Speckle tracking imaging combined with adenosine stress test was used to evaluate the longitudinal strain of left ventricular myocardium in mice.The vulnerability of the plaque was assessed by histopathology in serial tissue sections of proximal and middle left coronary artery according to the previously reported method.Results There were no significant differences in body weight,heart rate,left ventricular end diastolic volume,left ventricular end systolic volume,left ventricular mass and ejection fraction among the three groups(P>0.05).The levels of serum triglyceride,total cholesterol,high density lipoprotein and low density lipoprotein in stable plaque group and vulnerable plaque group were significantly increased when compared with those in control group(all P<0.05).The pathological results showed that the coronary luminal stenosis rates in the stable plaque group and the vulnerable plaque group were(74.3±4.9)%and(75.5±7.1)%respectively,with no significant difference between the two groups(P>0.05).MBF of the middle anterior septum and left ventricular posterior wall in the experimental groups were significantly decreased when compared with that in the control group both in the resting status and du

关 键 词：超声心动描记术 心肌造影 心肌灌注 心肌应变 易损斑块 

分 类 号：R543.3[医药卫生—心血管疾病]