实时三维超声心动图测量二尖瓣闭合线的方法及其准确性研究

Measurement of mitral valve closure line by real time three-dimensional echocardiography and its accuracy evaluation

目的探讨实时三维超声心动图技术对二尖瓣闭合线结构的成像和测量方法,寻找评价闭合线形态的定量指标,并验证测量方法的准确性。方法采用实时三维超声心动图技术对10只实验犬的活体心脏进行实时三维成像,将获得数据导入TomTec三维工作站对闭合线进行重建并分析。测量以下闭合线指标:①闭合线两端点之间的直线距离;②投影平面上的闭合线曲线长度;③闭合线中间段和侧段的两个夹角:命名为α和β角;最后测量离体心脏铅丝铸型标本的相对应指标,将两者进行比较。结果实时三维超声心动图对二尖瓣闭合线的各项测值与实际解剖标本对应的测值十分接近,并且具有很好的相关性与一致性。闭合线两端点之间的直线距离、投影平面上的曲线长度、α角和β角度数与实际测值之间相关系数r分别为0.857,0.839,0.755和0.748(P<0.05)。结论实时三维超声心动图技术能够较准确反映二尖瓣闭合线的形态结构,较适合用于二尖瓣闭合线形态学研究。

Objective To investigate the method and availability of analysis of mitral valve closure line by real time threedimensional echocardiography （RT-3DE）, search the quantitive index and validate the accuracy of RT-3DE in measuring closure line. Methods Ten canine heart was imaged by three - dimensional echocardiography in vivo and then the full - volume images was input into TomTec workstation and analyzed oflline. Then the following indexes were measured： straight- line distance between the two end points, curve length in the projection plane, α and β angle. At last, all measurements derived from RT- 3DE were compared with cardiac specimen in vitro. Results The parameters derived from RT- 3DE were highly identical with the anatomical specimen. There were good correlation and concordance between RT- 3DE and the anatomical specimen. The coefficient correlation of straight - line dis- tance between the two end points, curve＇length in the projection plane, α and β angle derived from RT- 3DE and specimen were 0. 857, 0.839, 0.755 and 0.748 （ P 〈 0.05）. Conclusion RT - 3 DE technology can display the stucture of mitral valve closure line exactly and is fit to investigate the configuration of mitral valve closure line.