组织同步显像对血运重建术前后左心室不同步性的研究

Intraventricular dyssynchrony analysis by tissue synchronization imaging before and after revascularazation

目的应用组织同步显像（TS1）技术研究冠心病患者血运重建术前后左室运动不同步性的变化。方法选择26例行血运重建术且左前降支狭窄〉75％的患者作为病例组，分别于术前、术后1个月和3个月进行超声。心动图俭查。采集标准心尖四腔观、二腔观及三腔观的动态组织速度图像，应用TSI测量左室各壁基底段和中间段的达峰值速度时间（Tp）．并计算左室12节段Tp标准差（TSD），另选30例年龄相匹配的健康者作为对照组，观察血运重建术前、术后左室局部和整体运动同步性的变化。结果病例组术前病变节段Tp明显延迟，呈红色或黄色编码，术后1个月和3个月Tp明显改善，原红色编码区逐渐缩小，呈黄色或绿色，但部分节段与对照组比较差别仍有统计学意义（P〈0．01或P〈0．05）。TSD在病例组术前、术后1个月及术后3个月呈递减趋势，且均高于对照组，除术后1个月和3个月比较差异无统计学意义外，其余两两比较差异均有统计学意义（P〈0．01或P〈0．05）。结论TSI能够直观、定量评价左室心肌运动的同步性．血运重建术后左室壁运动的不同步性逐渐得以改善。

Objective To investigate the global and regional dyssynchrony of left ventricle in patients with coronary artery disease before and after revascularization by tissue synchronization imaging（TSI）. Methods Subjects with the left anterior descending coronary artery（I.AD） stenosis）75% who underwent revascularization （ n = 26） and normal controls （ n = 30） were studied with TSI. Echocardiography was performed one day before revascularization,then repeated one month and three month after the operation, respectively. The sample volumes were located at the mid-myocardium of base and middle segments in apical four ,two and three chamber view of left ventricle. The time-to-peak velocity（Tp） of all myocardial segments were examined to access the regional dyssynchrony, and the standard deviations of Tp of 12 segments（TSD） were calculated to evaluate the global dyssynchrony. Results Before revascularization,Tp of segments in the anterior wall and the interventricular septum in patients were more delayed than those of control group（ P 〈0.01 ） ,and the color coding of ischemic segments were red and yellow. After operation, Tp of delayed segments were significant improved, and the color coding turn to yellow or even green, but there was still significant difference of Tp between disease group and control group （ P 〈0.01 or P 0.05）. TSD decreased gradually on the preoperatative, early postoperative, and later postoperative echocardiogram,and it on each time point of the disease group were all longer than that of control group. An improvement of TSD was observed after revascularization,especially for the three month examination （ P 〈0. 01） ,but the difference between early and later postoperation was not significant（ P 〉0. 05）. Conclusions The asynchronous motion of LV is very obvious in CAD patients. After revaseularization, both global and regional dyssynehrony were improved gradually. Moreover, TSI is a convenient and non-invasive way to quantitatc left venlricular asynchrony with the parameters.