摘要
目的观察多巴酚丁胺负荷期间QT离散度(QTd)的变化情况,探讨其临床意义。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(右冠状动脉为靶血管),利用多巴酚丁胺超声负荷实验(DSE,0～40μg·Kg-1·min-1)检出冬眠心肌,之后成功复灌,处死动物,对心脏行TTC大体染色及光镜检查。分别于模型制备前后、DSE期间及复灌后观察QTd的变化情况。结果①10只动物(76.92%)成功制备成模型,病理检查未示心肌坏死改变。②模型制备成功后QTd较正常状态明显增加[(68.75±5.33)ms和(25.00±1.77)ms,P<0.05];复灌后明显降低[(35.62±3.47)ms和(68.75±5.33)ms,P<0.05],与正常状态差异无统计学意义[(35.62±3.47)ms和(25.00±1.77)ms,P>0.05]。③DSE期间QTd呈现先降低后增加的双相反应的变化趋势。④模型制备成功后的QTd与DSE检出的急性冬眠心肌节段数呈中等程度的负相关(r=-0.64,P<0.05)。结论①.急性冬眠心肌动物模型的QTd明显增加,早期有效复灌可降低QTd。②DSE期间急性冬眠心肌模型的QTd呈现双相反应趋势。③急性冬眠心肌模型的QTd是反映冬眠心肌数量的指标之一。
Objective To establish the animal model of acute hibernating myocardium （AHM） by the method of closed-chest, observe the changes of QT dispersion （QTd） of AHM and the effect of dobutamine on QTd of AHM, investigate the clinical significance. Methods 13 little domestic Chinese swine were established to the model of AHM by interventional method （closed-chest）, RCA was target vessel, standard dobutamine stress echocardiography （ DSE, 0-40 μg·Kg^-1·min^-1） were performed to detect hibernating myocardium. After reperfusion successfully, animals were killed, the heart was stained with TTC and the histomography changes of AHM cells were assessed by microscope. QTd were observed throughout the course. Results （ 1 ） 10 animals （76.92%）were established to the model of AHM successfully, myocardium necrosis were not found. （2） QTd increased significantly in AHM model [ （ 68.75±5.33 ） ms vs （25.00± 1.77 ） ms, P〈0.05 ], and decreased obviously after reperfusion successfully [ （35.62±3.47）ms vs （68.75±5.33）ms,P〈0.05]. There was no difference between normal status and reperfusion [ （ 35.62±3.47 ） ms vs （25.00± 1.77 ） ms, P〉0.05 ]. （ 3 ） During DSE, QTd appeared as the trend of biaphasic response. （4）QTd of AHM correlated to the amounts of AHM segments negatively （r=-0.64,P〈0.05）. Conclusion （1）QTd of AHM increased significantly, it decreased obviously after early reperfusion successfully. （2）During DSE, QTd appeared as the trend of biaphasic response. （3）QTd may be a valuable index which can reflect the amounts of hibernating myocardium.
出处
《中国心血管病研究》
CAS
2006年第10期769-772,共4页
Chinese Journal of Cardiovascular Research
基金
江苏省卫生厅重点科研项目(H9809)
