Study On Left Ventricular Function And Hemodynamics In Carriers Of Major Pathogenic Genes In Hypertrophic Cardiomyopathy By Multimodality Techniques

Part I The evaluation of early changes of left ventricular function of MYBPC3 gene mutation carriers in hypertrophic cardiomyopathy using three speckle tracking echocardiographyObjective: This study aims to detect the early variation in left ventricular systolic function in MYBPC3 gene mutation carriers of familiar hypertrophic cardiomyopathy(HCM)using three speckle tracking imaging(3D-STI).Methods: Seventy-seven subjects were divided into: MYBPC3 mutation carriers without left ventricular hypertrophy(G+P-)(N=27)and normal controls(n=50)of healthy family members.The data of conventional 2D,Doppler echocardiography and 3D-STE of left ventricle was saved and analyzed.The variables of 3D global systolic longitudinal strain(3D-GLS),3D global systolic radial strain(3D-GRS),3D global circumferential strain(3D-GC L)and 3D global area strain(3D-GAS).Results: Compared with the control group,MYBPC3 mutation carriers showed significantly lower value in 3D-GLS(P=0.001),GRS(P<0.05),e’/a’ and e’(P<0.05).E/Ea and EDT value of the G+P-group shows to be significantly higher than the control group.However,no difference was found in peak early(E)transmitral filling velocities and 3D-GC L.In identification of G+P-,ROC analysis showed that the sensitivity and specificity of 3D-GLS were 78% and 60%,respectively.Additionally,the sensitivity and specificity of 3D-GRS were 78% and 44%,respectively.Conclusions:The function of left ventricle changed in G+P-group of MYBPC3-HCM before the change of the cardiac structure.3D-STE could offer potential clinical evidence for early diagnosis of MYBPC3 gene mutation carriers.Part II Assessment of left ventricle systole energy loss in hypertrophic cardiomyopathy with the cardiac myosin binding protein C gene mutation using vector flow mappingObjective: Left ventricle structure and function were changed in hypertrophic cardiomyopathy with the cardiac myosin binding protein C(MYBPC3)gene mutation.The references are less about left ventricle hemodynamic of hypertrophic cardiomyopathy.This study aimed to assessment of left ventricle energy loss(EL)of vector flow mapping in MYBPC3 of hypertrophic cardiomyopathy.Methods : 7 members of a HCM family was studied.We calculated the energy loss of left ventricular in everyone on three chamber vector flow mapping frames,and analysised maximum of the sum and average EL of systole.Subjects were divided into HCM patients,carriers and non-carriers.Results: There are three subjects carrying MYBPC3 gene mutation in this family.The maximum of the sum and average EL of systole shows significantly increased in HCM.II-2 and II-5 are carriers,Compared with the non-carriers,their maximum of the sum and average EL of systole are increased.Conclusions: Maximum of the sum and average EL of systole were higher in HCM.The carriers maximum of the sum and average EL of systole are increased,compared with the non-carriers.EL could offer a new quantitative hemodynamic of left ventricular of HCM based on vector flow mapping.Part III The early identification of MYH7 mutation carriers of hypertrophic cardiomyopathy using conventional 2D echocardiographic and three-dimensional speckle tracking imaging multi-parameter analysis modelObjective:To create multi-parameter analysis model to improve the early diagnosis in different genes mutation carriers of familiar hypertrophic cardiomyopathy(HCM).Methods : Fifty-five subjects were divided into two groups: MYH7 mutation carriers without left ventricular hypertrophy(MYH7G+P-)(N=28)and MYBPC3 mutation carriers without left ventricular hypertrophy(MYBPC3G+P-)(N=27).The two groups’ clinical data,conventional 2D,Tissue Doppler imaging(TDI),Three-dimensional speckle tracking imaging(3D-STI)parameters were acquired,including maximum interventricular septum(IVSmax),maximum left ventricular posterior wall(PWmax),left atrial volume index(LAVI),left ventricular mass index(LVMI),mitral flow E and A velocities,E peak deceleration time(EDT),atrioventricular filling time,mitral annulus velocity e’ and a’ peak in diastolic and left ventricular ejection fraction(LVEF),isovolumic relaxation time(IVRT),isovolumic contraction time(IVC T).The global longitudinal peak strain(GLS),global circumferential peak strain(GCS),global radial peak strain(GRS)and global area peak strain(GAS)were acquired by 3DSTI.Each parameters were compared between MYH7G+P-groups and MYBPC3G+P-groups.Results: There were no significant difference in LVEF,E/A,E/e’,IVCT,IVRT,EDT,Atrioventricular filling time,GLS,GRS,as well as GCS in two groups.Compared with the control group,MYH7G+P-showed significantly increased in LAVI,IVSmax,LVPWmax,LVMI and GAS(P<0.01).For single parameter,area under the ROC curve(AUC)were successively PWmax>LAVI>IVSmax>LVMI>GAS(respectively: 0.772,0.738,0.733,0.719,0.714).AUC of multi-parameters was 0.912,the sensitivity and specificity were 85.2% and 96.3%,respectively.Conclusions: MYH7G+P-have early change in two groups.Conventional 2D echocardiographic multi-parameters together with 3DSTI analysis model can significantly improve the recognition efficiency of MYH7G+P-of familiar hypertrophic cardiomyopathy.Maximum left ventricular posterior ventricular wall is an independent predictor of distinction MYH7G+P-and MYBPC3G+P-.