Assessment Of Left Ventricular Function In Type-2 Diabetes Mellitus By Tissue Doppler Imaging Measuring Mitral Annular Motion And Tei-index

BackgroundVentricular walls motion plays an important role in the clinical practice.Two -dimentional echocardiography is used to be the most popular technique used for noninvasive assessment of ventricular walls motion based on visual interpretation of endocardial excursion and wall thickening.Doppler tissue imaging(DTI)that preserves the low doppler shift frequencies of high energy generated by the walls motion with a high-frequency transducer,a low wall filter,and low gain setting contains potential information for the assessment of myocardia proerties.Pulsed wave DTI(PW-DTI)offering a high ternporal resolution and accurate myocardium velocity is of primary importance in evaluating left ventricular function.Quantitation of the ventricular systolic and diastolic functions in the longitudinal axis is clinically relevant since the contraction of the ventricle in this direction is mainly due to subendocardial fibers.Motion of mitral annular longitudinal dynamics shows the motion of the cardiac base and is easy to be detected.so,longitudinal motion velocity of mitral annular measured for the asse-ssment of left ventricular diastolic dysfunction(LVDD)by PW -DTI had been researched and reported successfully.Currently,most traditional measurement of Tei index is by Pulsed Doppler,and it' s flow time interval is not in the same cardiac cycle.and Tei index measured by Tissue Doppler Imaging(TDI)overcomes this shortcoming.Tei index obtained from the TDI also is independent of heart rate,blood pressure and cardiac geometry.it's measuring method is simple,repeatable,So TDI-Tei index is a very useful parameter for the overall evaluation of cardiac function.ObjectiveA number of experimental,pathologic,and epidemiologic studies support the existence of diabetic cardiomyopathy.The cardiomyopathy may be an important contributor to heart failure and ill prognosis of diabetic patients.Left ventricular function was regarded specially by PW-DTI and Tei index comprised with MPWD in order to differentiate LVDD more early and exactly.MethodsA GE system Five instrument was used to obtain echocadiographic images.60 normotensive asymptomatic patient with well-controlled type-2 DM(30 without syndrome and 30 with syndrome),30 health volunteers were studied by PW-DTI and MPWD during left ventricular filling and constriction respectively.Four position of mitral annular were measured by PW-DTI including systolic velocity Sa,early diastolic velocity Ea,end diastolic velocity Aa and DTI-Tei.Early mitral inflow velocity E,end mitral inflow velocity A,left ventricular isovolumetric relaxation (IVRT)and E apex deceleration time(DT)were measured by MPWD.ejection fraction (EF)were measured by M-mode echocardiography.All indexes were measured during 3-5 heart beats.Their average value Ea/Aa ratio and E/A ratio were calculated.Results1.DM-1 groups Compared with control groups,Ea,Ea/Aa ratio(P＜0.01),Sa at AW and PS of LV b were significantly decreased,DT were lengthened(bothP＜0.05),Tei index were Heightened(P＜0.01),there are difference in statistics.2.DM-2 groups Compared with control groups,Ea,Ea/Aa ratio and E,E/A Ratio,Sa(holding normal)and b were significantly decreased,DT and IVRT was prolonged; Tei index were Heightened,there are obvious difference in statistics(P＜0.01).3.There was no change in EF in DM Compared with in control. 4.There was an difference in PW-DTI and MPWD in distinguishing LVDD of type-2 DM patients.The LVDD diffentiated rate in group DM was 93.33%by PW-DTI and 71.67%by MPWD.ConclusionsTDI and TDI-Tei index can comprehensively evaluate left ventricular function in patients with DM early。because it is simple,objective,non-invasive,reproducible and easier to accept,so it not only provides an accurate and objective diagnosis for the clinical evaluation of left ventricular function of patients with DM,but also establishs the foundations for further clinical treatment.