斑点追踪成像结合腺苷负荷超声评价心肌梗死患者心肌存活性

目的探讨运用二维斑点追踪技术（Two—dimensionalSpeckleTrackingImaging，2DSTI）结合腺苷负荷超声心动图，观察心肌梗死患者心肌旋转运动、评价其存活性的可行性。方法选择35例陈旧性心肌梗死患者在静息状态及腺苷作用（140ngOkg-1 mm-1，持续6min）下，观察其左心室各节段峰值旋转角度（PeakRotation，Prot）及收缩期峰值旋转率（Peak—systoleRotationRate，PRRs）。以核素心肌灌注，代谢显像结果作为金标准，将各节段划分为存活及非存活心肌进行比较研究。结果在基础状态下，存活组与非存活组间的二尖瓣及心尖水平心肌Prot、PRRs无显著性差异（P〉O．05）。腺苷负荷后，存活组二尖瓣及心尖水平心肌Prot、PRRs（绝对值）均明显升高，而非存活组的二尖瓣及心尖水平心肌Prot、PRRs无显著性变化。以腺苷负荷后APRot（％）≥14．5％作为截断值、识别存活心肌的敏感性和特异性分别为91．26％（115／126）、88．23％（90／102）；以腺苷负荷后APRRs（％）≥18．5％作为最佳截断值，其识别存活心肌的敏感性和特异性分别为88．89％（113／126）、86．27％（88／102）；联合APRot（％）与APRRs（％）两项指标，其敏感性和特异性分别为94．41％（119／126）、90．19％（92／102）。结论二维斑点追踪成像结合腺苷负荷超声心动图观察心肌旋转运动，可以作为一种识别心肌梗死患者存活心肌较可靠的新方法。

Evaluation of Viable Myocardium by Speckle Tracking Imaging under Adenosine Stress Echocardiography in Patients with Myocardial Infarction

Objective To explore a new method to evaluate myocardium viability by two-dimensional speckle tracking imaging （2DSTI） combined with adenosine stress echocardiography in the patients with myocardial infarction. Methods The regional peak rotation （PRot） and peak-systole rotation rate （PRRs） of each segment were detected using 2DSTI in 35 cases of patients with elderly myocardial infarction at rest and adenosine （140/zg.kg-~.min4, continuing 6 min）. And then, every corresponding segment were defined as viable or non-viable myocardium according to radionuclide myocardial perfusion / metabolic imaging. Results At baseline, there was no significant difference in PRot and PRRs between viable and nonviable myocardium segments. And under adenosine stress, PRot and PRRs of myocardial segments at the mitral or apical levels in viable group increased significantly while didn＇t change remarkably in the nonviable in contrast with those at rest. Compared with those in nonviable group, PRot and PRRs of myocardial segments at mitral or apical levels in viable group increased significantly respectively, Using a cutoff of 14.5%,/kPRot had a sensitivity of 91.26% and specificity of 88.23% for distinguishing viable from nonviable segment. Using a cutoff of 18.5%, z~PRRs had a sensitivity of 88.89% and specificity of 86.27% for distinguishing viable from nonviable segment. Combined with PRot and PRRs, the sensitivity and specificity could reach 94.41% and 90.19%. Conclusion Speckle tracking imaging combined with adenosine stress echocardiography could provide a reliable and new method for identifying viable myocardium from evaluating myocardium rotation motion.