经食道三维超声分析继发性二尖瓣关闭不全的结构特点

Analysis structural characteristics of mitral valve caused by chronic secondary mitral regurgitation by means of the real-time three-dimensional transesophageal echocardiography

目的:借助经食管实时三维超声心动图及量化分析软件,分析继发性二尖瓣关闭不全(SMR)时二尖瓣结构的特点。方法:选择继发于主动脉关闭不全致二尖瓣重度反流组20例与正常对照组20例均行经食管实时三维超声心动图检查,并使用Tom Tec-Arena 1.0-4D MV-Assessment 2.3软件进行后处理分析。结果:左心室舒张末期内径组间差异显著,慢性继发性二尖瓣关闭不全(CSMR)组较对照组明显增大(P<0.01);与正常组相比较,CSMR组的瓣环前后径、左右纤维三角间径、瓣环周长、瓣环面积均增大(P<0.05),瓣环球形指数及前后瓣环间角度差异无统计学意义。CSMR组瓣环高度较正常组小(P<0.05)。AHCWR即瓣环高度与跨前后交界间径的比值,通常认为其值减低提示二尖瓣环变平。CSMR组AHCWR值较正常组减小(P<0.05)。对瓣叶的分析,前叶面积及前叶瓣环至闭合缘的长度较对照组均差异无统计学意义,而后叶面积及后叶瓣环至闭合缘的长度较对照组增大(P<0.05)。两组间后叶与瓣环夹角、二尖瓣前叶对合缘长度、二尖瓣后叶对合缘长度均无明显差异。CSMR组二尖瓣前后径与主动脉瓣环间夹角较对照组增大(P<0.05)。对瓣环的动态分析发现,CSMR组二尖瓣环最大位移、瓣环面积的压缩比均较对照组减小(P<0.05)。结论:重度主动脉关闭不全继发二尖瓣关闭不全,伴随左心室的增大二尖瓣环扩张、变平,二尖瓣瓣叶闭合障碍。

Objective： This study set out to analysis structural characteristics of mitral valve （MV） caused by chronic secondary mitral regurgitation by means of the real-time three-dimensional transesophageal echocardiography （RT3DTEE） and quantitative analysis software. Methods： Forty patients underwent RT3DTEE study： 20 patients with chronic secondary mitral regurgitation and 20 patients with normal MV used as control subjects（CS）. TomTec-Arena 1.0-4D MV-Assessment 2. 3 software was used to measure parame- ters of annular dimensions and geometry, leaflet surface area and so on. Results： There is a Significant differ- ence between CSMR and CS group that the left ventricular end-diastolic diameter of CSMR significantly in- creased （P 〈 0. 01 ）. Compared with CS group, the parameters include AP diameter, AL-PM diameter, Annu- lus circumference, Annulus area had increased （ P 〈 0. 05 ） , however, the Sphericity index and Non-planar An- gle had no statistical difference. The Annular Height of CSMR decreased （ P 〈 0. 05 ）. AHCWR, namely the ratio of Annular Height to Commissural Width, is generally accepted as an index which reflects the degree of mitral valve annular nonplanar. The CSMR group had smaller AHCWR（ P 〈 0. 05 ）. There is no difference beween two groups in anterior leaflet area, diameter of anterior annular to closure line length, but posterior leaflet area and diameter of posterior annular to closure line length were increased significantly（ P 〈0. 05 ）. Parameters of posterior leaflet angle, anterior closure line length （3D）, posterior closure line length had no statistical difference between groups, besides Angle AAo-AP, the angle constituted by AP diameter and aortic annular planar, had increased in CSMR group. From the automatic dynamic analysis, the parameters of Annular Dis- placement （max）, Annulus Area Fraction （2D） decreased considerably in CSMR group（P 〈 0. 05 ）. Conclusion： MV annular became Dilated and flattened, accompanied by expanded left ventricular in CSMR secondary to severe aortic insufficiency, and systolic MV closing forces decreased.