超声斑点追踪应变率成像技术结合多巴酚丁胺负荷试验评价冠状动脉粥样硬化性心脏病患者存活心肌的价值

目的探讨超声斑点追踪应变率成像技术(SRI)结合多巴酚丁胺负荷试验(DSE)评价冠状动脉粥样硬化性心脏病患者存活心肌的临床价值。方法 27例经超声心动图检查存在左心室室壁节段性运动异常和左心室收缩功能障碍(左心室射血分数<50%)的冠状动脉粥样硬化性心脏病患者,经皮冠状动脉介入治疗(PCI)之前进行联合DSE的斑点追踪SRI成像及双核素单光子发射型断层显像(DISA-SPECT)检查。PhilipsiE33彩色超声诊断仪分别录入静息及DSE状态下斑点追踪SRI图像并存储,Qlab7.0定量分析软件计算各节段的纵向收缩期峰值应变率(LSR)。所有患者在完成联合DSE的SRI及DISA-SPECT检查后1周内进行PCI术。术后1、3、6个月时分别复查超声心动图,PCI术后室壁运动改善作为判定存活心肌的金标准。绘制受试者操作特性曲线(ROC)评价LSR检测存活心肌的敏感度及特异度。结果超声心动图检出165个室壁运动异常节段(RWMA),PCI术后超声心动图(金标准)检出存活心肌106(64.2%,106/165)个节段,非存活心肌59(35.8%,59/165)个节段。DISA-SPECT检测出存活心肌104个节段,非存活心肌61个节段,与PCI术后超声心动图比较,其敏感度、特异度和准确性分别为87.7%(93/106)、81.4%(48/59)和85.5%(141/165)。静息状态下SRI参数LSR预测存活心肌ROC下面积为0.694(P<0.001),截断点为-1.08,敏感度为66.7%,特异度为62.7%;联合DSE后ROC下面积为0.859(P<0.001),截断点为-1.30,敏感度和特异度分别为84.4%和85.3%,较静息时均有显著提高(χ2=9.082、7.394,P<0.05)。静息状态下存活心肌和非存活心肌LSR分别为(-1.12±0.17)s-1、(-1.05±0.14)s-1,差异有统计学意义(t=16.84,P<0.01);DSE后存活心肌和非存活心肌LSR分别为(-1.64±0.31)s-1、(-1.09±0.42)s-1,差异亦有统计学意义(t=11.87,P<0.01)。SRI联合DSE检测冠状动脉粥样硬化性心脏病患者存活心肌与DISA-SPECT相比,敏感度略低(84.4%vs87.7%)、特异度略高(85.3%vs81.4%),但差异无统计学意义(χ2=0.621、0.241,P>0.05)。联合DSE的SRI检测存活心肌与DISA-SPECT有良好的相关性(rn=0.819,P<0.001)。结论联合DSE的SRI参数LSR检测存活心肌的敏感度及特异度较静息时均有显著提高,联合DSE的SRI检测冠状动脉粥样硬化性心脏病患者存活心肌的敏感度和特异度与DISA-SPECT基本相同,并具有良好的相关性。

Assessment of myocardial viability in the patients with coronary artery disease by speckle tracking strain rate imaging combined with dobutamine stress echocardiography

Objective To explore the significance and value of two-dimensional speckle-tracking strain rate imaging（SRI） combined with dobutamine stress echocardiography（DSE） for evaluation of viable myocardium in the patients with coronary artery disease（CAD）.Methods twenty-seven hospitalized patients with regional wall motion abnormalities（RWMA） and left ventricular systolic dysfunction（left ventricular ejection fraction,LVEF50%） were included in our study.Before coronary angiography and percutaneous coronary intervention（PCI）,all of them were examinated by speckle-tracking SRI combined with DSE by Philips iE33 and dual isotope simultaneous acquisition single photon emission computed tomography（DISA-SPECT）.Every segment image was acquired and evaluated by wall-motion analysis.By using the Qlab7.0 software,the images of SRI were analyzed quantitatively for the long axis peak-systolic longitudinal strain rate（LSR）.PCI was performed within one week after SRI combined with DSE and DISA-SPECT in all patients.The movement of each segment was observed by routine echocardiography 1,3,6 months after PCI,and the presence of improvement was taken as the gold standard of viable myocardium.The area of receiver operating characteristic curves（ROC） was used to assess the sensitivity and specificity of LSR in detection of viable myocardium.Results Of the 165 segments with abnormal wall motion by routine echocardiography,106（64.2%,106/165） showed viable myocardium by gold standard,while 59（35.8%,59/106） showed nonviable myocardium.The sensitivity,specificity and accuracy of DISA-SPECT for assessment of viable myocardium were 87.7%（93/106）,81.4%（48/59） and 85.5%（141/165）.At rest,the LSR of viable and nonviable myocardium were（-1.12±0.17）s^-1 and（-1.05±0.14）s^-1（t=16.84,P〈0.01） respectively.The area of receiver operating characteristic curves（AUC） was 0.694（P〈0.001）with a cutoff of-1.08.The sensitivity and specificity were 66.7% and 62.7%.When combined with DSE,the LSR of viable and nonviable myocardium were（-1.64±0.31）s^-1 and（-1.09±0.42）s^-1（t=11.87,P〈0.01）respectively.The AUC increased significantly up to 0.859（P〈0.001） with a cutoff of-1.30.The sensitivity and specificity improved to be 84.4% and 85.3%（χ2=9.082,7.394,both P〈0.05）.In detecting viable myocardium in the patients with CAD,the sensitivity of LSR combined with DSE was slightly lower than DISA-SPECT（84.4% vs 87.7%）,while the specificity was much higher than DISA-SPECT（85.3% vs 81.4%）.But they were no significant difference（χ2=0.621,0.241,both P〈0.05）.There was a good correlation between SRI combined with DSE and DISA-SPECT in detecting viable myocardium（rn=0.819,P〈0.001）.Conclusions The sensitivity and specificity of LSR in quantitative SRI analysis improved significantly when combined with DSE.The sensitivity and specificity of LSR combined with DSE were similar to DISA-SPECT in detecting viable myocardium in the patients with CAD.