Study Of Changes Of Mitral Apparatus In Patients With Mitral Valve Repair By Three-dimensional Echocardiography

Object:To research the changes of the parameters of the mitral apparatus inpatients with mitral valve prolapse before and after the mitral valve repair,and to explore the correlations of mitral regurgitation area and theparameters. To investigate the clinical significance of the mitral valvecoaptation height index (CHI) in the mitral valve annuloplasty.Methods:Thirty patients with pure mitral valve prolapse were enrolled,underwent mitral valve repair in China-Japan Union Hospital fromJanuary2012to October2013. Mitral valve images were acquired byreal-time three-dimensional transesophageal echocardiography(RT-3D-TEE). Quantitative analyses of parameters such as height ofprolapse （HProl）, volume of prolapse （VProl）,annuluscircumference(C3D), anterolateral to posteromedial diameter of annulus(DAIPm), anteroposterior diameter of annulus (DAP), length of A2(L2DDA2), length of P2(L2DDP2), length of anterior combination（LCA3dLf）, length of posterior combination （LCP3dLf）, area ofposterior leaflet （A3DTpost）, area of anterior leaflet (A3DTant) werecarried out by mitral valve quantification (MVQ) software in thepreoperative date and immediately postoperative date. Mitralregurgitation area（MR）were calculated in the preoperative date andimmediately postoperative date. The mitral valve CHIs in each mitral valve area (A1-P1, A2-P2, A3-P3) were measured by thethree-dimensional quantification(3DQ).Results:Before the operation, HProl, VProl, C3D, DAIPm, DAP, L2DDA2,L2DDP2, LCA3dLf, LCP3dLf, A3DTpost, A3DTant and MR were（7.12±3.86）mm,（1.26±1.11）ml,（150.30±22.08）mm,（43.89±8.42）mm,（39.39±5.73） mm,（23.82±6.23） mm,（17.24±3.72） mm,（42.52±10.24）mm,（45.92±11.64）mm,（796.63±226.71）mm2,（1240.10±418.93）mm2,（17.56±5.94）cm2. After the operation, theabove parameters were （3.35±1.64） mm,（0.18±0.15） ml,（107.37±12.97） mm,（31.79±4.19） mm,（28.64±4.57） mm,（21.53±3.14）mm,（9.33±3.67）mm,（29.56±8.06）mm,（29.33±7.76）mm,（358.23±115.55）mm2，（736.22±167.80）mm2,（1.61±1.27）cm2. The latter parameters were significantly smaller than the formerwith significant differences (t=5.260,5.582,14.620,9.054,14.967,2.354,8.712,7.221,9.335,13.046,8.681,15.485, all P<0.05). LCP3dLf waslonger than LCA3dLf with significant differences before the operation(t=-4.614, P<0.05), but without significant difference after the operation(t=0.319, P>0.05). The multiple linear regression equation was expressedas: Y(MR)=-0.191+0.031X1(A3DTpost)-0.350X2(L2DDA2). L2DDA2and A3DTpost were independent factors of MR, MR was inverselyproportional to L2DDA2, but proportional to A3DTpost. Thepreoperetive CHIs were A1-P1area(11.56±0.92)%， A2-P2area(4.59±0.57)%， A3-P3area(5.61±0.68)%; the immediatelypostoperative CHIs were A1-P1area(30.23±1.72)%， A2-P2area(35.12±1.65)%， A3-P3area(30.57±1.83)%. The CHI changed significantly before and after the operation (t=10.527、17.174and13.967，all P<0.05).Conclusion:The general parameters after the operation were smaller than theparameters before the operation. LCA3dLf and LCP3dLf are different,which will lead to mitral valve regurgitation, so it is significant to ensurethe length of LCA3dLf be equal to LCP3dLf. In order to reduce MR, it isnecessary to keep enough and reasonable L2DDA2and not to makeA3DTpost too big during the operation. It is stereo intuitive, accuratepositioning to acquire CHI with the slice plane of three-dimensionalimage and realise real-time assessment of mitral valve Involution degree.