Evaluation Of Left Ventricular Systolic Function In Patients With Type2Diabetes Mellitus By Two-Dimensional Speckle Tracking Imaging

Objects:The purpose of this study is to assess LV systolic longitudinal,radial,circumferential strain and LV twist in patients with type2diabetes mellitus (T2DM)and to evaluate its clinical application by STI,and estimate the influence to systolicfunction by diabetic microangiopathy.Methods:.53patients with T2DM(25with T2DM only [B group]and28patients withcoexisting DM and microangiopathy[C group]) as well as30healthy volunteers(control group,A group) were enrolled. High frame rate two-dimensional images ofthree consecutive cardiac cycles were recorded from the LV apical four-chamberview, two-chamber view, long-axis view and the short-axis views at the levels ofmitral annulus, papillary muscle and apex of the LV respectively.2D images weretransferred to Qlab7.1work station for offline strain analysis, acquired the peaksystolic strain of each segment and calculated the average value of three consecutivecardiac cycles as the peak systolic strain. The average strain values of the basalsegment, the middle segment, the apical segment of the LV long axis and mitralannulus, papillary muscle and apex of the LV short axis in the endocardial,epicardial and global layers were calculated as the LV strain of each level in theendocardial, epicardial and global layers respectively, and mural strain wasevaluated. The LV global LS, RS and CS were the average values of the LV strain ofeach level in the endocardial,epicardial and global layers respectively. LV systolicendocardial,epicardial,mural and global rotation at the levels of mitral annulusand apex and LV peak systolic global twist were evaluated.Results:1. the LS values gradually increased from base to apex(P＜0.05),LS values atendocardial layers showed higher than those of the epicardial layers(P＜0.05),the transmural gradient and the peak LS of every view in the B,C group lower thancontrol group (P <0.05), the C group are lower than B group (P <0.05).2. the RS values at endocardial layers showed higher than those of the epicardial layers(P＜0.05),the value at the level of papillary muscle was the largest,the peak RS of Bgroup were significantly higher than A group and C group (P <0.05), the difference ofRS between the A group and C group was not statistically significant (P>0.05).Transmural gradient between the three groups was no significant difference (P>0.05).3. the CS values at endocardial layers showed higher than those of the epicardiallayers(P＜0.05),the left ventricular CS values and the transmural gradient strain of Cgroup is lower than A group and B group (P <0.05)；A group were no significantdifferences about B group (P>0.05).4. At the same level,the rotation and thetorsion at subendocardial layers were higher than subepicardial layers(P<0.05)；thepeak rotation in the apex level and peak rotation of subepicardial in the mitralvalve level and peak torsion of LV are: C＞B＞A group (P <0.05); peak muralrotation in the apex level,LV mural torsion are: A＞B＞C group (P <0.05); thesubendocardial peak rotation and peak bulk rotation in mitral valve level in B,Cgroup were higher than A group (P <0.05), group were no significant differencesabout A group (P>0.05), peak mural rotation in the mitral valve level were lowerthan A group (P <0.05), but no significant difference between B,C group (P>0.05).Conclusion:1. Compared with normal control group, LV longitudinal systolic function indiabetic patients without microangiopathy were reduced,radial systolic function androtation,twist compensatory increased,circumferential systolic function had nosignificant change； diabetes patients with microangiopathy LV longitudinal,circumferential systolic function were reduced, radial systolic function had nosignificant change,and rotation,twist is further increased,Prompted that type2diabetes in patients with left ventricular systolic function has been the event ofdamage did not appear before the clinical symptoms of impaired heart function,and with the advent of microangiopathy, the reduction of systolic function is moreobvious.2. Healthy subjects and T2DM patients' LV endocardial myocardial systoliclongitudinal, radial and circumferential peak strain and rotation, twist were higherthan the same section of subepicardial myocardium. Prompted that there are the transmural gradient between the different layers of myocardial, and the transmuralgradient decreased with the emergence of the extension of the duration of diabetesand diabetic microangiopathy,the transmural gradient can identify early myocardialsystolic dysfunction in patients with T2DM.3. the change of LV myocardial systolic longitudinal, radial and circumferentialpeak strain and rotation, twist about diabetic patients with normal LVEF,can not bedetected by conventional echocardiography. While2DSTI technology can becomprehensive evaluated, and no angular dependence, the repeatability of bettermeasurement process is relatively simple. The prompt2DSTI myocardial movementand deformation in the two-dimensional gray-scale image quantitative analysis canprovide a richer amount of information compared with conventional echocardi-ography, More accurate assessment of type2diabetes in patients with left ventricularglobal and regional myocardial function.