舒张期面积应变指数判断左前降支重度狭窄的价值

The value of area strain imaging diastolic index for predicting left anterior descending severe stenosis

目的 应用三维斑点追踪技术获取左前降支（LAD）供血心肌节段的舒张期面积应变指数（ASI-DI）,探讨其在判断LAD重度狭窄以及定位狭窄部位方面的价值.方法 自2012年7月至2014年4月,入选在武汉大学人民医院拟诊冠心病的住院患者92例进行回顾性分析.冠状动脉造影前检查超声心动图,研究对象的左心室射血分数≥50％,且无节段性室壁运异常.根据LAD狭窄程度,将患者分为3组：重度狭窄组（狭窄程度≥75％）,共36例;轻中度狭窄组（狭窄程度1％～74％）,共22例;对照组（冠状动脉无狭窄）,共34例.应用三维斑点追踪技术获取整体收缩期峰值面积应变（GPSAS）、整体舒张期面积应变指数（GASI-DI）以及节段心肌的ASI-DI等超声心动图参数.绘制节段心肌ASI-DI判断LAD重度狭窄的受试者工作特征（ROC）曲线,获取最优节段和截断值.结果 重度狭窄组、轻中度狭窄组和对照组之间的GPSAS差异无统计学意义[分别为（-25.2±6.2）％、（-20.3±6.6）％和（-21.3±8.6）％,P=0.159].重度狭窄组的GASI-DI值均小于轻中度狭窄组和对照组[分别为（-34.3±14.7）％、（-48.1±13.3）％和（-59.4±12.2）％,P均＜0.01],轻中度狭窄组的GASI-DI值与对照组比较差异无统计学意义（P=0.217）.前壁基底段ASI-DI判断LAD近段重度狭窄的ROC曲线下面积为0.829,截断值为40.3％,敏感度和特异度分别为0.96和0.63;前间壁中间段ASI-DI判断LAD中远段重度狭窄的ROC曲线下面积为0.843,截断值为38.8％,敏感度和特异度分别为0.967和0.651.结论 ASI-DI可以筛选出左心室射血分数≥50％且无节段性室壁运异常的LAD重度狭窄患者.前壁基底段和前间壁中间段ASI-DI能够较好地分别定位LAD近段和中远段重度狭窄.

Objective To evaluate the value of locating and defining severe stenosis of left anterior descending （LAD） with area strain imaging diastolic indexes （ASI-DI） derived from three dimensional speckle tracking imaging （3D-STI）.Methods A total of 92 suspected coronary heart disease patients with left ventricular ejection fraction （LVEF） ≥ 50% and without regional wall motion abnormality,who underwent echocardiography before coronary angiography in our department from July 2012 to April 2014,were included in this retrospective study.Patients were divided into three groups by the level of LAD stenosis：severe stenosis group （≥75%,n =36）,mild to moderate stenosis group （1%-74%,n =22） and control group （without coronary artery stenosis,n =34）.Global peak systolic area strain （GPSAS）,global ASI-DI （GASI-DI）,and ASI-DI of the regional myocardial segments with blood supplied by LAD were measured.Receiver operating curves （ROC） were obtained between ASI-DI and stenosis level of LAD to locate and to find out the optimal segment and cutoff values.Results There was no significant difference of GPSAS among serious stenosis group,mild and moderate stenosis group and control group （（-25.2 ± 6.2）% vs.（-20.3 ±6.6）% vs.（-21.3 ±8.6）%,P =0.159）.GASI-DI was significantly lower in severe stenosis group than in mild to moderate stenosis group and control group （（-34.3 ± 14.7） vs.（-48.1±13.3）% vs.（-59.4 ± 12.2）%,both P〈0.01）.GASI-DI was similar between mild to moderate stenosis group and control group （P =0.217）.The optimal cutoff values of ASI-DI were 40.3% and area under the curve （AUC） were 0.829 in the base anterior segment for detecting proximal severe stenosis of LAD （sensitivity 0.967,specificity 0.651）,38.3% and 0.843 in the middle anteroseptum for detecting mid-distal sever stenosis of LAD （sensitivity 0.967,specificity 0.651）.Conclusions Patients with severe LAD stenosis can be screened by ASI-DI among patients with LVEF≥50% and without regional wall motion abnormality.The ASI-DI of base anterior segment and middle anteroseptum can be used to locate the proximal and mid-distal sever stenosis of LAD.