二维径向应变显像在心肌梗死诊断中的应用价值探讨

The Application Value of Two-Dimensional Radial Strain Imaging in the Diagnosis of Myocardial Infarction

目的应用超声二维径向应变显像(2D-STI)与冠状动脉造影(CAG)结果对照,探讨左室径向运动指标收缩期峰值径向应变(SR)、应变率(SRs)、径向位移(DR)在诊断节段性室壁运动异常中的临床应用价值。资料与方法采集34例心肌梗死患者和36例正常对照者左室短轴(二尖瓣、乳头肌、心尖)三个水平二维灰阶动态图。应用二维应变分析软件测量三个水平各节段心肌收缩期峰值SR、SRs、DR,并与冠脉造影结果比较分析,得出径向运动指标诊断心肌运动异常的特异性、敏感性、阳性预测值、阴性预测值、Youden指数。结果心梗组梗死节段峰值SR、SRs、DR在二尖瓣、乳头肌水平均低于对照组,心尖水平部分节段低于对照组(P<0.05),不同程度冠脉狭窄组的SR、SRs、DR比较,差异有统计学意义(P<0.01)。SR、SRs、DR检测异常心肌的灵敏度分别为67%、72%、80%;特异度分别为73%、76%、81%;阳性预测值分别为73%、77%、82%;阴性预测值分别为76%、72%、69%;Youden指数分别为0.40、0.48、0.61。结论 2D-STI可评价心肌坏死的程度,为临床治疗提供可靠信息,为节段性室壁运动障碍提供更为客观、科学的方法。径向指标--DR可作为判断冠状动脉病变情况的良好指标。

Purpose To discuss the clinical application value of left ventricular peak systolic radial strain （SR） , strain rate （SRs） , displacement （DR） in the diagnosis of segmental ventricular wall abnormal motion by comparing the results of two-dimensional radial strain imaging （2D-STI） and coronary angiography （CAG） . Materials and Methods The high frame rate two-dimensional images of 34 patients with myocardial infarction and 36 healthy subjects were collected, which included the levels of mitml annulus, papillary muscle and apex. Measuring the myocardium＇s SR, SRs, DR using two-dimension strain analysis software. The results were Compared with CAG to calculus the sensitivity, specificity, positive predictive value, negative predictive value and Youden index. Results The segment of infarction＇s SR, SRs and DR of the healthy subjects were lower at the papillary muscle and mitral annulus level than those of the patients, and at apex level, only part of the indicators were lower （P〈0.05）. The SR, SRs, DR of different degrees of coronary stenosis were statistical significant （P〈0.01）. Sensitivity ofSR, SRs, DR to detect abnormal cardiac were 67%, 72%, and 80%, respectively; specificity were 73%, 76%, and 81%,respectively; positive predictive value were 73%, 77%, and 82%,respectively; negative predictive value were 76%, 72%, and 69%,respectively;Youden index were 0.40, 0.48, and 0.61,respectively. Conclusion 2D-STI can evaluate the degree of myocardial necrosis, provide some reliable information for clinic and provide a scientific method for segmental ventricular wall abnormal motion. The index of DR can be used to judge pathological changes of the coronary artery.