二维斑点追踪分层应变技术定量评价冠状动脉慢血流患者左心室收缩功能的价值

Quantitative evaluation of left ventricular systolic function in patients with slow coronary blood flow by two-dimensional speckle tracking hierarchical strain technique

目的探讨二维斑点追踪成像(2D-STE)分层应变技术定量评价冠状动脉慢血流(CSF)患者左心室收缩功能的应用价值。方法选择2018年7月—2021年10月陕西中医药大学附属医院心血管内科收治并经冠状动脉造影(CAG)确诊的CSF患者48例为研究对象(CSF组),再纳入经CAG确诊为冠状动脉血流正常者48例作为对照组,2组患者均采集动态二维超声心动图声像图,采用Echo Pac软件从各切面对2组患者左心室3层心肌分层应变进行脱机分析,记录各节段左心室肌分层应变参数,并计算2组左心室心肌整体纵向分层应变(GLS)、环向分层应变(GCS)及各层心肌跨壁应变梯度△GLS和△GCS。采用ROC曲线分析左心室分层应变参数诊断CSF患者左心室收缩功能的效能。结果CSF组患者前降支、回旋支、右冠状动脉TIMI血流帧数(TFC)显著高于对照组(t/P=3.355/0.001、3.084/0.003、2.910/0.004)。2组患者舒张末期室间隔厚度、舒张末期左心室后壁厚度、左心室舒张末期容积、左心室收缩末期容积、左心室每搏输出量及左心室射血分数比较,差异均无统计学意义(P>0.05)。2组患者左心室心肌各层GLS与GCS由内膜向外膜均表现为逐层递减的特征,CSF组患者心内膜下层、中层及外层GLS与△GLS较对照组患者降低(t/P=2.068/0.044、2.020/0.049、2.196/0.033、2.062/0.045);2组患者左心室心肌GCS、△GCS比较差异无统计学意义(P>0.05)。ROC曲线显示,△GLS最佳截断值为-4.765,曲线下面积(AUC)为0.764,优于心内膜下层、中层及外层GLS单独预测效能(Z=2.163、2.653、2.325,P<0.05)。结论基于2D-STE的心肌分层应变技术可更为敏感地定量评价CSF患者左心室收缩功能受损情况,具有较好的临床应用价值。

Objective To investigate the application value of two-dimensional speckle tracking imaging(2D-STE)layered strain technique to quantitatively evaluate left ventricular systolic function in patients with coronary slow flow(CSF).Methods A total of 48 patients with CSF who were admitted to the Department of Cardiovascular Medicine,Affiliated Hospital of Shaanxi University of Traditional Chinese Medicine and confirmed by coronary angiography(CAG)from July 2018 to October 2021 were selected as the research subjects(CSF group),and then included in the CAG confirmed coronary artery Forty-eight patients with normal blood flow served as the control group.Dynamic two-dimensional echocardiographic sonograms were collected from both groups of patients.Echo Pac software was used to analyze the layered strain of left ventricular layer 3 of the two groups of patients from each section.parameters,and calculated the global longitudinal layered strain(GLS),circumferential layered strain(GCS)and transmural strain gradients△GLS and△GCS of the left ventricular myocardium in the two groups.The ROC curve was used to analyze the efficacy of left ventricular layered strain parameters in diagnosing left ventricular systolic function in patients with CSF.Results The TIMI flow frame number(TFC)of the anterior descending artery,circumflex artery and right coronary artery in the CSF group was significantly higher than that in the control group(t/P=3.355/0.001,3.084/0.003,2.910/0.004).There was no significant difference in end-diastolic ventricular septal thickness,end-diastolic left ventricular posterior wall thickness,left ventricular end-diastolic volume,left ventricular end-systolic volume,left ventricular stroke volume and left ventricular ejection fraction between the two groups(P>0.05).The GLS and GCS of each layer of the left ventricular myocardium in the two groups showed the characteristics of decreasing layer by layer from the endocardium to the outer layer,and the GLS and△GLS of the subendocardium,middle layer and subepicardium in the CSF group were lower than those in the control group(t/P=2.068/0.044,2.020/0.049,2.196/0.033,2.062/0.045).There was no significant difference in left ventricular myocardial GCS and△GCS between the two groups(P>0.05).The ROC curve showed that the best cut-off value of△GLS was-4.765,and the area under the curve(AUC)was 0.764,which was better than the individual prediction performance of subendocardial,middle and subepicardial GLS(Z=2.163,2.653,2.325,P<0.05).Conclusion The myocardial layered strain technique based on 2D STE can more sensitively and quantitatively evaluate the impairment of left ventricular systolic function in CSF patients,and has good clinical application value.