心肌声学造影无创评价犬急性冠状动脉闭塞缺血心肌及侧支循环的状态

目的：探讨经静脉心肌志学造影在动态评价犬急性冠状动脉闭塞时缺血、坏死心肌，及侧支循环逐步建立开放中的价值。方法：7只健康杂种犬，分别于基础状态，左冠前降支（LAD）结扎即刻、结扎后3h行经静脉心肌声学造影（MCE）。定量分析冠脉闭塞后心肌低灌注区视频密度峰值（VI），测量充盈缺损区面积，监测血流动力学变化。结果：1只犬于LAD结扎2min时因发生室颤死亡，统计分析时剔除，其余6只犬经静脉MCE未见血流动力学影响。LAD结扎3h的造影充盈缺损面积小于结扎即刻（P＜0．001）；LAD结扎3h的心肌低灌注区视频密度峰值较结扎即刻明显增加（P＜0．001）；心肌病理染色确定的坏死心肌部位在MCE的充盈缺损范围内。结论：MCE是反映心肌血流灌注的安全、有效方法，可准确评价冠脉急性闭塞时心肌血流灌注的变化及侧支循环状态。

Experimental study on myocardial ischemia and collateral recruitment after acute coronary occlusion by myocardial contrast echocardiography

Objective To evaluate the value of intravenous myocardial contrast echocardiography(MCE) on the assessment of myocardial ischemia,infarction and collateral recruitment after coronary occlusion.Methods Seven anesthetized open chest normal dogs were performaed by MCE.The myocardial perfusion was observed at baseline conditions,instant and 3 hours after LAD occlusion.Quantitative assessment of myocardial videointensity was analysed by AD software,and the negative contrast area was also measured.Hemodynamic changes were assessed.Results one dog died of ventricular fibrillation.The intravenous contrast echocardiography were observed on the other six dogs.The negative contrast area at 3h after occlusion was lower than that at instant after occlusion( P <0 001);The myocardial video intensity in the anterial wall was significantly higher at 3h after occlusion than that at instant after occlusion( P <0 001).The myocardial infarction areas by TTC stained corresponded with that by MCE.Conclusion MCE is a safe and efficient method on assessing myocardial perfusion.The myocardial perfusion and coronary collateral recruitment after coronary occlusion could be measured by MCE.