急性冬眠心肌动物模型的制备及多巴酚丁胺负荷超声心动图的检测价值

The experimental study of establishing an animal model of acute hibernating myocardium and its performance in two-dimensional echocardiography after dobutamine infusion

目的 使用闭胸法建立急性冬眠心肌动物模型 ,以病理学指标为“金标准” ,探讨多巴酚丁胺超声负荷试验 (DSE)检测急性冬眠心肌的价值。方法 对 13只小型中国家猪采用闭胸介入法制备急性冬眠心肌模型 (以右冠状动脉为靶血管 ) ,采用完整的DSE方案 (0～ 40 μg·kg-1·min-1)检测急性冬眠心肌 ,以目测半定量法观察的双相反应为标准 ,评价其检出价值。实验结束后处死实验动物 ,观察心肌细胞的病理改变。结果 ① 10只 (76.92 % )实验动物成功制备急性冬眠心肌模型 ,大体染色未示心肌坏死灶 ,光镜仅示缺血的非特异性改变。②模型制备成功后 ,160个节段中有 10 5个节段运动正常 ,3 3个运动减弱 ,2 2个运动消失 ,无一节段表现为反常运动 ;DSE期间 ,41个节段发生双相反应 ,DSE检出急性冬眠心肌的阳性率为 74.5 4% ;运动减弱节段发生双相反应的比例高于运动消失节段 (84.85 %vs 5 9.10 % ,P <0 .0 5 )。结论 以双相反应为标准 ,DSE对急性冬眠心肌有较高的检出价值 ;

Objective The pathological index of myocardium was considered as 'gold standard', to investigate the value of dobutamine stress echocardiography (DSE) in detecting acute hibernating myocardium(AHM) by establish an animal model of AHM.Methods Thirteen little domestic Chinese swine were established to the model of AHM by interventional method with angioplasty ballon (closed chest),then they underwent different stages of DSE(0～40 μg·kg -1 ·min -1 ),the segments which appeared biaphasic response were considered AHM; In the end, animals were killed, the heart was stained with TTC and the histomography changes of AHM cells were assessed by microscope. Results ①Ten animals(76.92%)were established to the model of AHM successfully, myocardium necrosis were not found, swelled nucleolus and dilatated capillaries were found under the microscope. ②Among 160 segments, the wall motion of 105 segments was normal, 33 hypokinesia, 22 akinesia; biphasic response appeared in 41 segments during DSE. The positive percentage of DSE in detecting AHM was 74.54 %. The incidence of biphasic response was higher in hypokinesia segments than akinesia segments( 84.85 % vs 59.10 %,P< 0.05 ).Conclusions DSE can detect AHM moderately efficient while biphasic response as a standard,and AHM is more exist in the form of hypokinesia.