三维超声评估圆锥动脉干畸形左心功能的研究

Study on three-dimensional echocardiography for quantifying left ventricular function in conotruncal defects

目的探讨三维超声（3DE）评估圆锥动脉干畸形（CTD）心功能的准确性及其临床意义。方法对52例CTD患儿进行心室容量、室壁质量等3DE测量，并与二维超声（2DE）双平面Simpson法测值、对照组3DE测值及CTD患儿术后心功能情况比较。结果方差分析、SNK均数间两两比较和直线相关分析显示：CTD病变心脏2DE测值低估较明显，与CTD术后心功能表现的相关性（r=0．20，P=0．2086）低于3DE（r=0．39，P=0．0090），但正常心脏3DE、2DE测值差异无统计学意义。与对照组相比，CTD的左心功能有不同程度减低，表现在左室收缩末期容量升高及搏出量、射血分数降低。其中有术后低心排表现者的舒张末期容量小于对照组，其搏出量、射血分数更低，差异有统计学意义（P〈0．05），致耐受手术创伤差，易发生术后低心排。结论准确的3DE心功能定量评估可完善CTD术前诊断，对其矫治手术有指导意义，对可能出现的术后低心排进行早期干预。

Objective To evaluate the accuracy and value of ventricular function in conotruncal defects（CTD） by three-dimensional echocardiograpby（3DE）. Methods Fifty-two children with CTD and forty-three children with normal hearts were examined by 3DE. The measurements of left ventricular volume and wall mass were outlined and calculated. The measurements of left ventricular volume and wall mass of 3DE in preoperative CTD were compared with those of 2D biplane Simpson-method in preoperative CTD, 3DE in control group and 2D biplane Simpson-method in control group. The results of 3DE and 2DE preoperative measurements were also compared with their postoperative clinical cardiac conditions. Results From the findings of analysis of variance and Student-Newman-Keuls（SNK） test, there was no significant difference between 3DE and 2DE measurements of left ventrieular function in normal children,but there was significant difference between 3DE and 2DE measurements of left ventricular function in children with CTD. 2DE measurements of left ventricular volume and wall mass in the CTD group were significant underestimated and less correlated with their postoperative clinical cardiac conditions （ r = 0.20, P = 0. 2086） than 3DE measurements （ r = 0.39, P = 0. 0090）. Furthermore, left ventricular function in the CTD group was poorer than that in the control group. Stroke volume and effective function were reduced due to increasing end systolic volume, while left ventricular wall mass was increased due to the possible compensation of its ventricular muscle. With the lower end-diastolic volume, stroke volume and effective function, patients were more likely to have the occurrence of postoperative low cardiac output. Conclusions By making a precise quantitative assessment, 3DE is very useful in providing more information for preoperative diagnosis in CTD and predicting such postoperative prognoses as the occurrence of postoperative low cardiac output.