术中冠脉血流显像技术评价急性心肌梗死犬心肌血流灌注的研究

目的探讨术中冠脉血流显像（CFI）技术观察急性心肌梗死犬心肌血流灌注的应用价值。方法18只健康开胸杂种犬于前降支分出第一对角支后约1 cm处结扎3小时建立急性心肌梗死模型。分别于结扎前、结扎3小时后应用i13L高频探头观察前降支远端及前壁心尖段心肌内血流灌注程度、血流方向,并测量心肌内冠脉血流速度,同时在以上观察时点经股静脉匀速推注造影剂（C3F8）行心肌声学造影（MCE）检查对照。结果18只犬均成功建立急性心肌梗死模型。结扎前降支3 h后,根据MCE显示前壁心尖段有无造影剂充填分为无侧支循环形成组（A组）和侧支循环形成不充分组（B组）,A组10只犬中,CFI显示60%（6/10）未见血流信号显示,40%（4/10）前壁心尖段内仅见星点状血流信号。B组7只犬中,CFI则均显示有少量血流信号,与基础状态相比,舒张期峰值血流速度（D-Vmax）、收缩期峰值血流速度（S- Vmax）及D-Vmax/S-Vmax比值均明显降低（P〈0.05）。另有1只犬MCE显示前壁心尖段造影剂充填良好,CFI亦显示丰富的血流信号,舒张期峰值血流速度（0.65 m/s）快于基础状态峰值血流速度（0.28 m/s）。结论术中冠脉血流显像技术能直观、无创、敏感地显示心肌血流灌注状态,与MCE比较,能更敏感的反映心肌血流灌注。

Coronary flow imaging technique during operation evaluating the myocardial perfusion in the mongrel''s acute myocardial infarction model

Objective To investigate the value of the coronary flow imaging (CFI) technique in assessing the myocardial perfusion during operation. Methods Eighteen anesthetized open-chest dogs were performed the acute myocardial infarction models by ligating the left anterior descending (LAD) 3 hours. Before ligating LAD, CFI was performed by i13L probe to observe the perfusion of LAD and apical-anterior wall separately, then the contrast agent (C₃F₈) was injected into femoral vein to perform myocardial contrast echocardiography (MCE) examination. After ligating LAD 3-hour, CFI and MCE were performed again. Results All 18 dogs were successfully performed acute myocardial infraction models. 3 hours after ligating LAD, in A group (n=10) that MCE displayed no microbubble filled in apical-anterior wall, CFI showed 60% (6/10) had no flow signal in apical-anterior wall, and 40% (4/10) had a little flow signals. B group (n=7) that MCE showed some microbubbles filled in apical-anterior wall had some flow signals in the same position by CFI too, and the peak velocity in diastolic phase (D-Vmax), the peak velocity in systolic phase (S-Vmax), the ratio of D-Vmax and S-Vmax all were obviously lower than those before ligating LAD (P<0.05). One dog filled very well by microbubbles in MCE, had full flow signals in CFI, but the D-Vmax in model was faster than the one in normal period (0.65m/s vs 0.28 m/s). Conclusion CFI during operation could directly, noninvasvely, sensitively evaluate the myocardial perfusion, and had an advantage of MCE.