斑点追踪成像技术鉴别诊断扩张型心肌病与缺血性心肌病的价值探讨

Evaluation of speckle-tracking imaging in differential diagnosis of dilated cardiomyopathy and ischemic cardiomyopathy

目的 探讨斑点追踪成像（STI）技术对扩张型心肌病（DCM）及缺血性心肌病（ICM）的鉴别诊断价值.方法 对40例DCM、32例ICM患者及30例对照组行超声心动图检查,记录左室各切面高帧频图像,应用STI技术测量心肌18个节段长轴纵向应变（Tls）、短轴圆周应变（Tcs）及径向应变（Trs）的达峰时间,同时计算出各峰值应变达峰时间的最大差（Ts-dif）及标准差（Ts-SD）.比较两组间各参数差异,并采用受试者工作特征（ROC）曲线确定诊断的敏感性、特异性.结果 ICM组各节段Tls、Tcs及Trs的达峰时间的最大差（Ts-dif）及标准差（Ts-SD）均高于DCM组,差异有统计学意义（P＜0.05）.通过ROC曲线得出Trs-dif及Trs-SD曲线下面积分别为0.920、0.946,以170 ms及53 ms为截断值诊断两种疾病的敏感性、特异性、准确性分别为87.5％、87.5％、87.5％及90.6％、90％、90.2％.结论 通过STI技术得到各应变指标的Ts-dif及Ts-SD鉴别DCM和ICM的敏感性和特异性很高,可以在二维图像的基础上进一步诊断两种疾病,其中以Trs-SD的诊断效力最大,为临床诊断提供了新的参考依据.

Objective To explore the differential diagnostic value of speckle-tracking imaging （STI） between dilated cardiomyopathy（DCM） and ischemic cardiomyopathy（ICM）.Methods 40 DCM patients,32 ICM patients and 30 normal controls were enrolled for this study.Different views of high frame images of left ventricle were recorded.The time to peak radial strain,circumferential strain and longitudinal strain of 18 myocardial segments were measured by STI,and the maximum differential （Ts-dif） and the standard deviation（Ts-SD） of time to the peak strain were calculated.The left ventricular parameters measured by STI were compared between DCM and ICM,and the diagnostic sensitivity and specificity were investigated by the areas under the receiver operating characteristic （ROC） curves.Results Parameters of different segments of ICM were obviously higher than those of DCM （P ＜ 0.05）,and there were significant differences between ICM and DCM.The areas under the ROC curves of Ts-dif and Ts-SD to radial strain were 0.920 and 0.946 respectively.At the cut off of 170 ms and 53 ms for diagnosing DCM and ICM,the sensitivity,specificity and accuracy were 87.5％,87.5％,87.5％ and 90.6％,90％,90.2％ respectively.Conclusions These strain parameters by STI,especially Ts-SD to peak strain can offer a new quantitative diagnostic method in distinguishing DCM from ICM.