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

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

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(C_3F_8)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。

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.