小剂量多巴酚丁胺负荷超声结合心肌背向散射评价存活心肌

目的：观察小剂量多巴酚丁胺负荷超声（LDDSE）结合心肌背向散射积分（IBS）检测存活心肌的应用价值。方法：选取22例经定量冠状动脉造影（QCA）确诊为冠心病的患者,行经皮冠脉介入治疗术（PCI）,术前1周内行LDDSE[5、10μg/（kg.min）两级负荷]检查,于静息、LDDSE每级负荷5 min采集全心尖切面（长轴、二腔、四腔）IBS图像,术后（3个月）复查二维超声和IBS检查。根据心肌背向散射周期变化幅度（CVIB）值在小剂量多巴酚丁胺负荷过程中增加的特点,探索CVIB最大变化值K值定义存活心肌,并检测K值识别存活心肌的敏感性、准确性。与LDDSE进行比较。结果：与小剂量多巴酚丁胺负荷超声相比,负荷超声结合心肌背向散射的K值检测存活心肌敏感性、准确性明显提高（91.1%vs 77.8%、90.4 vs 75.7%,均P〈0.05）。结论：LDDSE结合IBS技术较LDDSE能提高检测存活心肌的敏感性和准确性。

Assessment of viable myocardium by low dose dobutamine stress echocardio-graphy combined with integrated backscatter

Objective： To observe the clinical value of low dose dobutamine（Dob） stress echocardiography（LDDSE） combined with integrated backscatter for identifying viable myocardium in patients with coronary artery disease（CAD）.Methods： 22 patients who were diagnosed CAD by quantitative coronary artery（QCA） and percutaneous coronary intervention（PCI） were performed further.DSE [5,10 μg/（kg·min）] were performed one week before PCI.IBS images at rest and every grade infusion of Dob 5 minutes were obtained in total apical views（Lax,2-ch,4-ch）.Two-dimension echocardiography and IBS were examined after three months of PCI again.The maximum changing value of CVIB（K value） during DSE was defined as the criterion of viable myocardium,then the sensitivity and accuracy were compared between LDDSE and DSE combined with IBS.Results： The sensitivity,accuracy of LDDSE combined with IBS were significantly higher than those of LDDSE（91.1% vs 77.8%,90.4 vs 75.7%,all P0.05）.Conclusion： Identifying viable myocardium by LDDSE combined with IBS has higher sensitivity,accuracy than those of single LDDSE.