MCE 与2D-STI 评价不同冠状动脉狭窄程度患者的心肌灌注水平与收缩功能

目的： 应用心肌声学造影(myocardial contrast echocardiography，MCE) 与二维斑点追踪技术(twodimensional speckle tracking imaging，2D-STI)评价不同程度冠状动脉狭窄时心肌灌注水平与收缩功能的变化。方法： 选取25 例冠心病患者行MCE，2D-STI及冠状动脉造影检查，各患者心肌节段根据冠状动脉造影中冠状动脉狭窄情况 分为4 组：A组(正常冠状动脉)、B组(轻度狭窄50%~75%)、C组(中度狭窄76%~90%)及D组(重度狭窄91%~100%)。 经过MCE和2D-STI 软件采样及计算，记录每组心肌节段MCE定量指标血容量、血流速度、血流量及2D-STI 定量指 标心肌纵向应变值，并比较其差异。结果： B，C及D组定量指标血流速度、血流量逐渐减小，差异有统计学意义 (P<0.05)，A组血容量、血流速度、血流量与B组无明显差异(P>0.05)，4 组间心肌纵向应变值差异均有统计学意义 (P<0.05)。结论：MCE及2D-STI 可评价不同冠状动脉狭窄程度的心肌灌注水平与收缩功能，2D-STI 发现冠状动脉轻 度狭窄的能力较MCE更好。

Evaluation of myocardial perfusion and systolic function in patients with different degree of coronary artery stenosis by MCE and 2D-STI

Objective: To study myocardial perfusion and systolic function in patients with different coronary artery stenosis by myocardial contrast echocardiography (MCE) and two-dimensional speckle tracking imaging (2D-STI). Methods: MCE, 2D-STI and coronary angiography were conducted in patients with coronary heart disease in our hospital. Myocardial segments were divided into 4 groups according to the degree of coronary artery stenosis: group A (normal group), group B (mild stenosis, 50%-75%), group C (moderate stenosis, 76%-90%) and group D (severe stenosis, 91%-100%). Blood volume, blood flow velocity, blood flow and longitudinal myocardial strain value (SL) in each group were measured by analysis software for MCE and 2D-STI. The differences in blood volume, blood flow velocity, blood flow and SL were evaluated. Results: The blood flow velocity and blood flow in B, C and D groups were decreased gradually, with significant difference (P<0.05). There was no significant difference in blood volume, blood flow velocity, blood flow between group A and group B (P>0.05). There were significant differences in SL among the 4 groups (P<0.05). Conclusion: There is a good correlation between coronary stenosis degree and myocardial perfusion or systolic function. The ability of 2D-STI to detect mild stenosis of coronary artery is better than MCE.