二维斑点追踪检测心肌跨壁应变梯度在非ST段抬高型心肌梗死中的应用

Application of two-dimensional speckle tracking for evaluation on transmural myocardial strain gradient in patients with non-ST-elevation acute myocardial infarction

目的探讨应用二维斑点追踪超声心动图(STE)检测心肌跨壁应变梯度(TMSG)识别非ST段抬高型心肌梗死(NSTEMI)的准确性。方法对58例首次NSTEMI患者(冠状动脉造影前)和50名健康成年人行STE检查,分别测量心内膜下心肌和心外膜下心肌的径向、圆周应变及跨壁应变梯度,并进行统计学分析。结果梗死心肌心内膜下心肌的径向和圆周应变均低于正常心肌(P均<0.001),跨壁梯度显著减小(P均<0.001)。应用TMSG-RS预测梗死心肌的ROC曲线下面积最大(AUC=0.87,P<0.001),以TMSG-RS≤-7.24%为界值,诊断NSTEMI的敏感度和特异度分别为89.30%和80.40%。结论 NSTEMI时梗死心肌的跨壁应变梯度显著减小;STE可通过检测心肌TMSG-RS准确识别梗死心肌。

Objective To explore the accuracy of two-dimensional speckle tracking echocardiography （STE） for evaluation on transmural myocardial strain gradient （TMSG） in identifying infarcted myocardium in patients with non-ST-elevation acute myocardial infarction （NSTEMI）. Methods Fifty-eight patients with NSTEMI before coronary artery angiography and 50 normal subjects underwent STE . The radial strain （RS） and circumferential strain （CS） of subendocardial myocardium and subepicardial myocardium were measured and analyzed statistically. Results RS and CS of subendocardial infracted myocardium were larger, and TMSG was lower than that of normal myocardium （all P〈0.001）. The major determinants of infracted myocardium was TMSG-RS. Taking TMSG-RS ≤-7.24% as the indicator of prognosticated infracted myocardium, the sensitivity was 89.30%, and the specificity was 80.40%. Conclusion TMSG-RS decreases obviously in patients with NSTEMI, and the infracted myocardium can be detected with STE.