The Study Of Left Ventricular Systolic Function And Synchronization Of Ventricular Wall Motion In Patients With Hypertrophic Cardiomyopathy By Two-Dimensional Speckle Tracking Technology

Objective: To study the changes of left ventricular systolic function and the synchronicity of ventricular wall motion in patients with Hypertrophic Cardiomyopathy(HCM)by two-dimensional dot tracking technique,and to explore the clinical value of two-dimensional dot tracking technique in patients with Hypertrophic Cardiomyopathy(HCM).Methods: From June 2019 to December 2020,35 patients with HCM and 35 healthy subjects who came to our hospital for examination and diagnosis were collected for routine echocardiography,and twodimensional dynamic images of each standard section of the left ventricle were obtained and stored.The interventional septal thickness(IVST),left ventricular end-diastolic diameter(LVEDD)and left ventricular posterior wall thickness(PWT)were measured on the long axial view of the left parasternal ventricle.Then,according to the body surface area(BSA),left ventricular mass index(LVMI)was obtained.Left ventricular ejection fraction(LVEF)was measured by M-type echocardiography to compare the parameters between the two groups.Simpson’s biplane method was used to measure left ventricular ejection fraction,left ventricular enddiastolic volume(EDV),left ventricular end-systolic volume(ESV)and stroke volume(SV).The difference of left ventricular volume parameters between the two groups was compared.Use Philips EPIQ 7C ultrasonic diagnostic instrument built-in automatic cardiac motion quantification software to obtain left ventricular global longitudinal strain(global longitudinal strain,GLS),18-segment longitudinal strain,18-segment longitudinal strain peak time,the peak time of Longitudinal strain(TLS),and the peak time of longitudinal strain-standard deviation(TLS-SD)are used to compare the parameter differences between the two groups.The correlation between IVST,LVMI and SV and GLS in the two groups was analyzed.Another sonographer randomly selected 15 subjects for repeatability measurement and used intra-group correlation coefficient between different observers for repeatability test.Results: IVST and LVMI in HCM group were higher than those in control group(P<0.01),while LVEDD in HCM group was lower than that in control group(P<0.01).There was no statistically significant difference in LVEF(M)between the two groups measured by M-type echocardiography(P>0.05),and LVEF(S),EDV,ESV and SV in the HCM group measured by Simpson’s biplane method were lower than those in the control group(P<0.05),and there was statistically significant difference in LVEF measured by M type echocardiography and Simpson’s method in the HCM group(P<0.05).In comparison of myocardial motion strain and time parameters,GLS and longitudinal strain of 7 cardiac segments in HCM group were lower than those in control group(P<0.05),TLS-SD was significantly higher than that in control group(P<0.01),and the peak time of longitudinal strain of 12 segments was delayed than that in control group,the difference was statistically significant(P<0.05).In patients with HCM,SV,IVST and LVMI were correlated with GLS(r = 0.55,-0.39,-0.48,P<0.05).There was no correlation between SV,IVST and LVMI and GLS in the control group.The results of repeatability test showed that IVST,LVEDD,PWT,LVMI,LVEF(M-mode echocardiography and Simpson’s biplane method),EDV,ESV,SV,GLS,18 segments longitudinal strain,18 segments longitudinal strain peak time and TLS-SD parameters were consistent among the subjects,and the correlation coefficients within the group were all greater than 0.80.Conclusion:1.M-type echocardiography cannot accurately evaluate the systolic function of the left ventricle in the deformed left ventricle of patients with HCM,and Simpson’s biplanar method can more accurately evaluate the systolic function of the heart of patients with HCM than M-type echocardiography.2.The two-dimensional speckle tracking technology can quantitatively evaluate the longitudinal changes and synchronicity of left ventricular myocardial systolic movement in patients with HCM,and can accurately evaluate the overall and local systolic function of left ventricular myocardium,which has high clinical reference value.3.GLS in HCM patients was positively correlated with SV,and negatively correlated with LVMI and IVST.