【摘要】 目的应用二维斑点追踪成像技术(two-dimensional speckle tracking echocardiography,2D-STE)分析冠状动脉慢血流(coronary slow flow,CSF)患者左室心肌分层应变,研究2D-STE在临床上评估CSF患者左室各层心肌收缩功能的准确性及应用价值。方法设定CSF组41例(CSF患者)及对照组59例(冠状动脉造影检查结果正常者),分别采集存储6个切面观(心尖左室长轴、心尖四腔、心尖两腔及二尖瓣、乳头肌、心尖水平左室短轴)的动态二维超声图像,利用软件于各切面观脱机分析CSF组和对照组左室3层心肌(心内膜下、中层和心外膜下)的分层应变,分别计算出两组左室3层心肌整体纵向应变(global longitudinal strains,GLS)和整体环向应变(global circumferential strains,GCS)以及相应的跨壁应变梯度△GLS、△GCS。结果 CSF组及对照组左室3层心肌(心内膜下层、中层、心外膜下层)GLS和GCS均保持由内向外逐层递减的跨壁梯度特征;CSF组GLS、△GLS较对照组减低,差异有统计学意义(P<0.05),尤以心内膜下层GLS和△GLS降低更为显著(P<0.001);CSF组GCS、△GCS减低,但与对照组相比差异无统计学意义。应用ROC曲线计算分层应变参数预测CSF左室收缩功能,△GLS的曲线下面积最大(AUC=0.766,P<0.001),当△GLS取截断值为-4.87%时,灵敏度及特异度分别可达66.7%及76.3%。结论 2D-STE可通过评估心肌分层应变识别CSF患者左室3层心肌收缩功能受累的差异(心内膜下层为甚)。心肌纵向应变跨壁梯度△GLS可早期识别CSF患者的心肌收缩功能异常,具有临床诊断的应用前景。更多还原

【Abstract】 Objective To discuss the clinical value and accuracy of two-dimensional speckle tracking echocardiography(2 D-STE)for the evaluation of left ventricular systolic function of the coronary slow flow(CSF)by assessing left ventricular layer-specific myocardial strains in patients with CSF. Methods CSF group contained 41 patients with CSF,and 59 patients with normal coronary angiography results were involved as the control group.All 2-dimensional(2 D)echocardiographic images from6 standard views(apical views of long-axis,4-chamber,and 2-chamber;parasternal short-axis views of mitral valve,papillary muscle,and apical level)were acquired for offline analysis.Layer-specific strain from endocardium,mid-myocardium and epicardium of LV wall was analyzed by 2 D-STE software.Layerspecific global longitudinal strains(GLS)and global circumferential strains(GCS)were assessed at endocardium,midmyocardium and epicardium by2 D-STE.The transmural gradient between endocardial and epicardial(△GLS,△GCS)were calculated. Results GLS and GCS of each myocardium showed gradient descent,which is subendocardium>midmyocardium>subepicardium in both CSF group and control group.As comparing to the control group,GLS and △GLS in CSF group were significantly lower(P<0.05);especially the endocardial GLS and △GLS(P<0.001).There were no significant difference in both GCS and △GCS between CSF group and control group.The AUC of △GLS was biggest(AUC=0.766,P<0.001),and when the cut off value was-4.87%,the sensitivity and the specificity was 66.7% and76.3%,respectively. Conclusions 2 D-STE can identify left ventricular 3-layer contractility(especially the subendocardium)by assessing left ventricular layer-specific myocardial strains in patients with CSF.Meantime,lognitudinal transmural gradient △GLS can identify the abnormity of left ventricular contractility in patients with CSF and have the promising prospect of clinical diagnosis.更多还原