Quantitative Evaluation The Changes Of Mitral Apparatus In Patients With Acute Myocardial Infarction By Real-time Three Dimensional Echocardiography

Objective:To evaluate the changes of structure of the mitral valve in patients with acute myocardial infarction with different degree mitral regurgitation and different infarction parts by real-time 3D transthoracic echocardiography(RT 3D-TTE),to provide the basis for treatment.Methods:89 patients with acute myocardial infarction,aged 39 to 76 years,mean(52±11)years.Echocardiography were performed within 72 hours after the first diagnosis of acute myocardial infarction.According to the color Doppler ultrasonography,there were without MR group(n=27)and with MR group(n=62).According to the effective regurgitation area(EROA),the regurgitation group was divided into mild MR group(35cases)and moderate to severe MR group(27 cases).According to the different infarction parts,89 patients was divided into anterior wall infarction(n=50)and posterior wall infarction(n=39);In addition,30 healthy volunteers were selected as the control group.Left ventricular end-systolic diameter(LVESD)and Left ventricular end-diastolic diameter(LVEDD)were measured by conventional echocardiography,the imaging was analyzed offline with TomTec software to obtain Left ventricular end-diastolic volume(LVEDV),Left ventricular end-systolic volume(LVESV),Left ventricular ejection fraction(LVEF)and mitral annulus parameters.Compare of conventionalechocardiography parameters and mitral annulus parameters in normal control group,myocardial infarction group without MR group and with MR group.Compare of conventional echocardiography parameters and mitral annulus parameters between myocardial infarction group of varying degrees of MR.Compare of mitral annulus parameters between the same infarction location group with different degree of MR.Compare of conventional echocardiography parameters and mitral annulus parameters between the same degree of MR group with different infarction location.Results:1.Acute myocardial infarction without MR group compared with the normal control group,the annular circumference(AC)and nonplanar angle(NPA)increased;aute myocardial infarction with MR group compared with the normal control group,anterior-posteriordiameter(AP)? anterolateral-posteromedialdiameter(AL-PM)?commissural diameter(CD)? annular circumference(AC)? two-dimensional annular area(AA2D)? three-dimensional annular area(AA3D)? tenting volume(TV)? tenting height(TH)? non-planarity angle(NPA)increased(p<0.05)in MR group,annular height(AH)? maximum annular displacement(ADMax)and maximum annular displacement velocity(ADVMax)decreased(p<0.05).2.Different levels of MR group comparison,the levels of AP,AC,CD,AA2 D,AA3D,TV and TH in the MR group,mild MR group,and moderate to severe MR group were increased,the difference was statistically significant(p<0.05);in the moderate to severe MR group,AL-PM was significantly greater than mild MR group(p<0.05),AH and ADMax were significantly lower in the moderate to severe MR group(p<0.05).There was no significant difference between the mild MR group and the no MR group(p>0.05).ADVMax there was no significant difference between the moderate to severe MR group and the mild MR group(p>0.05).3.The different infarction location,different degree of MR patiens comparison,AP,AL-PM,AC,CD,AA2 D,AA3D,TV,TH in the moderate to severe group weresignificantly higher than those in the mild MR group(p<0.05),and AH was lower than that in the mild group.4.The same degree of MR,different myocardial infarction location patients comparison,in moderate to severe MR group,with inferoposterior wall infarction,AA2 D,AA3D were greater than that in the anterior wall infarction(p<0.05)and higher than that in the control group(p<0.05),but AP,AC,CD,AL-PM,TV,TH,AH,ADMax,ADVMax was no significant difference in mild group between inferoposterior wall infarction and anterior wall infarction(p>0.05).Conclusion:1.In patients with acute myocardial infarction without MR,mitral annular structure changed partly;with the degree of MR increased,mitral annular was not only presented as the size enlargement but also the flattening of its geometric shape.2.In the patients with the same degree MR but with different infarction location,mitral annulus area in the inferoposterior wall infarction is expanded more.3.Real-time three-dimensional transthoracic echocardiography can evaluate the mitral valve structure changes for clinical treatment options to provide a reference.