A Study On Mitral Valve Structure And Function By Real-time Three-dimensional Transesophageal Echocardiography In Patients During Mitral Valvuloplasty

Objective1.Real-time three-dimensional transesophageal echocardiography(RT-3D-TEE)was used to evaluate mitral valve structure changes in mitral valve plasty(MVP).2.RT-3D-TEE quantitative technique was used to evaluate the effect of and mitral valve function immediately in mitral valvuloplasty.3.Two-dimensional transthoracic echocardiography(2D-TTE)was performed after surgery to further analyze the effect of mitral valvuloplasty.Study object Select 40 cases of MVP patients with mitral regurgitation(MR),including 23 males and 17 females,aged 52.7±15.4 years old.Ultrasound instrument GE vivid E9 color Doppler ultrasound diagnostic instrument with 6VT-D transesophageal ultrasound probe(frequency 6 Hz),M5 Sc ultrasound probe(frequency 1~3Hz)and Echo PAC workstation.Methods1.Three-dimensional images of the mitral valve and left ventricle were collected before thoracotomy and after cardiopulmonary bypass with RT-3D-TEE.Measurement parameters included(1)mitral annulus structure parameters: annulus area(AA),annulus height(AH)(2)mitral valve structure parameters: Tenting volume(TV),Tenting height(TA),Tenting height(TH),anterior leaflet area(ALA),posterior leaflet area(PLA),total leaflet area/annulus area(TLA/AA)(3)mitral valve motion parameters: Annular Displacement(Dis A),Annular Displacement Velocity(V-Dis A),Tenting fraction%(TV%),Annulus area fraction(AA%)(4)Left ventricular parameters: Left ventricular end-diastolic volume(LVEDV)and ejection fraction(LVEF).Analysis the differences in mitral valve annulus,leaflets structure parameters,mitral valve movement parameters,and left ventricular parameters between before thoracotomy and after cardiopulmonary bypass.Then,analysis the correlation of Dis A,V-Dis A,TV%,AA% and LVEF.2.RT-3D-TEE was used to acquire two-dimensional,color Doppler and tissue Doppler images before thoracotomy and after cardiopulmonary bypass,respectively.(1)The mitral valve effective regurgitation orifice area EROA(cm2)was measured in color Doppler images of the four-chamber,five-chamber,and two-chamber view in the middle esophagus,calculating the mean value.Analysis the differences of EROA before thoracotomy and after cardiopulmonary bypass to evaluate the effect of mitral valvuloplasty.Then,analyze the correlation between the EROA and annulus and leaflets structure parameters.(2)Measure the displacement of the mitral annulus(MAD(cm))three times using anatomic M-mode echocardiography in the four-chamber,five-chamber,and two-chamber two-dimensional images of the middle esophagus.Calculate the average.The correlation between MAD and Dis A was analyzed.(3)Quantitative tissue velocity imaging(QTVI)was used to measure the systolic peak velocity(Vs(cm/s))of the mitral annulus three times in the transesophageal four-chamber,five-chamber,and two-chamber view tissue Doppler images,respectively.Calculate the average.The correlation between Vs and V-Dis A was analyzed.3.The changes of LVEDV(ml),LVEF(%),and mitral regurgitation were assessed by 2D-TTE postoperative follow-ups,then compared with preoperative.The effect of mitral valvuloplasty was further evaluated.Result1.RT-3D-TEE parameters(1)Structural parameters of the annulus: After cardiopulmonary bypass,AA and AH decreased compared with those before thoracotomy,and the difference was statistically significant(P<0.05).(2)Leaflets structural parameters: After cardiopulmonary bypass,TA,TV,ALA and PLA decreased compared with those before thoracotomy,and the difference was statistically significant(P<0.05).After cardiopulmonary bypass,TLA/AA increased compared with those before thoracotomy,and the difference was statistically significant(P<0.05).There was no significant difference in TH between before thoracotomy and after cardiopulmonary bypass(P>0.05).(3)Movement parameters of mitral valve: Dis A,TV%,and AA% were decreased after cardiopulmonary bypass compared with those before thoracotomy,and the difference was statistically significant(P<0.05).There was no statistical difference in V-Dis A after cardiopulmonary bypass compared with those before thoracotomy,(P>0.05).(4)Left ventricular parameters: LVEDV decreased after cardiopulmonary bypass compared with those before thoracotomy,and the difference was statistically significant(P<0.05).There was no significant difference in LVEF compared with before thoracotomy and after cardiopulmonary bypass(P>0.05).(5)There were positive correlation between Dis A,V-Dis,TV%,AA% and LVEF before thoracotomy(r=0.562,p=0.000;r=0.528,p=0.000;r=0.643,p=0.000;r=0.564(p=0.000).Dis A,V-Dis,TV%,AA% and LVEF were all positively correlated after cardiopulmonary bypass(r=0.528,p=0.000;r=0.516,p=0.001;r=0.838,p=0.000;r=0.734,p=0.000).2.Color Doppler,AMM and QTVI parameters(1)After cardiopulmonary bypass,the EROA decreased compared with that before thoracotomy,and the difference was statistically significant(P<0.05).There was a negative correlation between EROA and TV,TA,TH,TLA/AA before thoracotomy(r=-0.482,p=0.002;r=-0.541,p=0.000;r=-0.541,p=0.000;r=-0.824,p=0.000);No correlation with AA,AH,ALA,PLA(p>0.05).There was a negative correlation between EROA and TV,TA,TH,PLA,TLA/AA after cardiopulmonary bypass(r=-0.333,p=0.036;r=-0.352,p=0.026;r=-0.463,p=0.003;r =-0.442,p=0.004;r=-0.357,p=0.024);No correlation with AA,AH,and ALA(p>0.05).(2)The MAD had no significant difference before thoracotomy and after cardiopulmonary bypass(P>0.05).There was a positive correlation between MAD and Dis A before thoracotomy(r=0.869,p=0.000).MAD was positively correlated with Dis A after cardiopulmonary bypass(r=0.334,p=0.035).(3)The Vs had no significant difference before thoracotomy and after cardiopulmonary bypass(P>0.05).Vs was positively correlated with V-Dis A before thoracotomy(r=0.859,p=0.000).There was a positive correlation between Vs and V-Dis A after cardiopulmonary bypass(r=0.513,p=0.001).3.2D-TTE parametersPostoperative LVEDV and MR degree decreased compared with preoperative,and the difference was statistically significant(p<0.05).Postoperative LVEF had no significant difference compared with preoperative changes(p>0.05).Conclusion1.RT-3D-TEE can assess mitral valve morphological structure and function changes immediately during mitral valvuloplasty,and can provide valuable information for the success of mitral valvuloplasty.2.There was a good correlation between mitral valve motion parameters and left ventricular systolic function parameters measured by RT-3D-TEE.3.The mitral valve motion parameters measured by RT-3D-TEE have a good correlation with the mitral valve motion parameters measured by conventional echocardiography.4.Echocardiography can be used to evaluate the recent mitral valve function in patients after mitral valve repair,and has practical clinical significance.