小剂量多巴酚丁胺负荷超声斑点追踪成像评价顿抑心肌力学功能  

Detection of stunned myocardium using speckle tracking echocardiography combined with low-dose dobutamine stress

作　　者：唐磊[1] 尹立雪[2] 李文华[2] 苏莉[2] 沈洁[2] 

机构地区：[1]四川省宜宾市第一人民医院超声科,644000 [2]四川省人民医院超声医学研究所

出　　处：《中华超声影像学杂志》2012年第11期985-990,共6页Chinese Journal of Ultrasonography

基　　金：国家自然基金资助项目（30970698）

摘　　要：目的应用小剂量多巴酚丁胺负荷结合超声二维斑点追踪成像检测顿抑心肌力学状态，明确顿抑心肌与相邻正常心肌不同负荷状态力学参数差异及特征。方法10只开胸比格犬，结扎左冠状动脉前降支心尖部和心尖部末梢对角支60min后再灌注120min，建立左室前壁急性心肌缺血再灌注模型，按两级剂量（5、10μg·kg-1·min-1）持续静滴多巴酚丁胺；分别于基础状态、急性心肌缺血再灌注后、多巴酚丁胺负荷第一级和第二级时采集左室短轴观二尖瓣、乳头肌和心尖水平二维3个心动周期灰阶动态图像，VVI软件分析左室各短轴水平18节段心内外膜下心肌周向应变（CS）和径向位移（RD）收缩期峰值变化。测量左室收缩末内径（LVIDS）、左室舒张末内径（LVIDD）、左室射血分数（LVEF）、心率和主动脉瓣口前向血流速度时间积分（AV-VTI）。结果①4种状态间比较，LVIDD、LVIDS、LVEF、心率及AV—VTI5项参数差异均无统计学意义（P〉0．05）。②左室短轴观前壁心尖段和中间段心内外膜下CS、RD急性缺血再灌注后与基础状态相比明显减小，多巴酚丁胺负荷第一级与急性缺血再灌注后相比明显增大（P〈0．05），多巴酚丁胺负荷第一级和第二级与基础状态间比较，CS和RD差异无统计学意义（P〉0．05）。左室短轴前壁基底段心内外膜下CS、RD在4种状态间比较差异无统计学意义（P〉0．05）。③左室乳头肌水平前侧壁心内膜下心肌RD和前间隔心外膜下心肌CS在4种状态间改变同相邻前壁一致，前侧壁心外膜下心肌RD和心内外膜下心肌CS及前间隔心内膜下心肌CS在4种状态间无改变。结论①小剂量多巴酚丁胺负荷超声二维斑点追踪成像能准确检测出顿抑心肌异常力学状态。②心肌顿抑后，相邻正常心内膜下心肌RD收缩期峰值出现一定程度下降、相邻正常心内膜下心肌CS和心外膜下心Objective To detect stunned myocardium using low-dose dobutamine stress （DBS） combined with two-dimensional speckle tracking imaging （2D-STI）, and to evaluate the difference and characteristics of mechanical parameters in different conditions between stunned myocardium and adjacent normal myocardium. Methods The acute myocardium ischemia/reperfusion （I/R） of anterior wall of left ventriele（LV） was induced with 60 minutes ligation of left anterior descending coronary artery （LAD）,and with reperfusion of 120 minutes in 10 open-chest beagle dogs. Dobutamine was administered continuously via vein with two different dose of 5 μg·kg-1·min-1 and 10 μg·kg-1·min-1. At baseline, post ischemia/reperfusion,after the first DBS and the second, the gray-scale dynamic images of three cardiac cycle of left ventricular short axis at the levels of mitral annulus, papillary muscle and apex were acquired. The systolic peak of circumferential strain （CS）, radial displacement （RD） of eighteen segments of suhendocardium and subepicardium were analyzed by Speckle tracking workstation. LV end-systolic dimension（ LVIDS）, LV end-diastolic dimension （LVIDD）, LV eject fraction （ LVEF）, heart rate （ HR）, aortic valve forward flow velocity time integral（AV-VTI） were also measured. Results ①There was no statistical significance （ P〉0.05） under the conditions of baseline,post I/R,the first DBS and the second for LVIDD, LVIDS, LVEF, HR and AV-VTI. ② Compared with baseline, the peak systolic subendocardium and subepicardium CS,RD decreased significantly at the apex and middle of short-axis anterior wall of LV under the conditions of post I/R;The parameters of the first DBS was significantly increased compared with the I/R （P 〈 0.05）; There was no difference between the two DBS and baseline（ P〈0.05）. The peak systolic subendocardium and subepicardium CS, RD at the bottom segment of LV were no statistical significance under the four conditions. ③There was no difference for

关 键 词：超声心动描记术 压力 多巴酚丁胺 心肌顿抑 二维斑点跟踪成像 

分 类 号：R445.1[医药卫生—影像医学与核医学]