Clinical Studies Of Left Ventricular Systolic Function Using Two-dimensional Speckle Tracking Imaging

The left ventricular global contraction function's appraisal is the clinical conventional examination project, it plays an important clinical role in assessing the patient's therapeutic schedule and prognosis. The left ventricular ejective fraction (LVEF)has been in the daily clinical work is most commonly used and acceptted generally. But certain pathological state, same as the left ventricular expands, the ventricular wall thickening, will affect accuracy on assessing the left ventricular contraction function. Some research indicated that in the chronic congestive heart failure patient, the correlation between the left ventricular ejective fraction by echocardiography measuring and cardiac functional grading and the brain sodium peptide was bad, moreover the left ventricular ejective fraction by echocardiography measuring rely on the ultrasound image quality to a great extent. It has the important clinical significance to search the method for evaluating the left ventricular function with the non-image dependence, accurately, conveniently.Recent years, the Real-time three dimensional echocardiography(RT3DE)is the clinical new technology, could show heart's anatomic structure more direct-viewing and comprehensively, and it could be quantitative analysis heart function and blood stream dynamics change accurately. The existing research indicated: Compares with the traditional two-dimensional echocardiography, RT3DE can provide the more accurate and affluent message of heart's anatomic structure, it is close to the heart size and the function appraisal with golden standard MRI. But this method still rely on the image quality, and operate time-consuming, cannot be suitable for the clinical daily application.The left ventricular cardiac muscle's movement including the long axis and the minor axis direction's movement as well as the rotary motion concerned with the complex myofibrillar.the long axis direction movement play an important role in left ventricle's contraction, we can evaluate the global systolic function of left ventricle by the mitral annular plane systolic excursion. The former research mainly made use of M-mode echocardiography(MME)and tissume doppler imaging(TDI) to evaluate the global systolic function of left ventricle by the mitral annular plane systolic excursion,it was time-consuming, the angle dependence and the repeatability is bad. By speckle tracking imaging (STI) to evaluate the global function of the left ventricle is suitable the clinical conventional application, we only can mark the three site of valve ring and apex of heart, the technique of STI can calculate the mitral annular plane systolic excursion automatically, it is not only simple, feasibility, and not rely on patient's image quality, therefore,Recently developed the STI technology, traces myocardial motion path through the recognition the myocardial echo spot of two-dimensional image. In the two-dimensional sonogram foundation, we can designate the certain scope region of interest(ROI) in the ventricular wall following the cardiac cycle(CC). According to the organization gray scale, the analyse software automatically trace every frame image's myocard structure site of different image element in the region of interest, and compare with previous image's site, it can calculate each segment myocardial distortion in the region of interest. Because speckle tracking imaging is independence on doppler frequency shift and angle, it has not the angle influence between sound beam direction and the wall motion, therefore two-dimensional speckle tracking imaging can reflect myocardial movement more exactly. Some research indicated that the measurements using speckle tracking imaging have good correlation with sonomicrometry and myocard tagging magnetic resonance imaging(MRI), the difference between intra-observer and inter-observer is also small, the reproducibility and reliability is good. The STI may be a new modality to evaluate the region myocard movement, it can not only judge the region myocard movement's distortion ability of longitudinal, axial, radial direction, moreover can evaluate the left ventricle globle twisting motion. This research evaluate three directions'strain of left ventricle myocard and the left ventricle global twist and the systolic displacemen of mitral annulus by STI. The correlation between these parameter with LVEF is analyzed respectively. We approach the correlation in order to determine the global function of the left ventricle with simplicity and accuracy.The studies were divided into three parts. In the first part, to study three directions'strain of left ventricle myocard, the left ventricle global twist and systolic displacemen of characteristic by STI in healthy subjects, we analyzed the correlation between these parameter with LVEF respectively in order to determine the feasibility and the accuracy of mitral annulus displacement by speckle tracking imaging to evaluate the global function of the left ventricle.In the next two parts, we analyzed the correlation of left ventricle myocard strain's characteristic and LVEF and mitral annulus displacement in patients with dilated cardiomyopathy and hypertension with different patterns of left hypertrophic geometric models respectively. To observe the correlation bewteen different directions'motion method of left ventricle myocard and mitral annulus displacement under different pathologic state, hoping to find a new promising modality to evaluate the global systolic function of left ventricle for clinical routine practice with its simplicity and accuracy.Part I Evaluation of left ventricular systolic function in healthy subjects using two-dimensional speckle tracking imagingObjective: To determine the feasibility and the accuracy of mitral annulus displacement(MAD) by speckle tracking imaging to evaluate the global function of the left ventricle.Methods: The study population consisted of 36 healthy subjects, male 21, female 15,average age 38.4±15.4 years.The patients took the decubitus, high frame rate two-dimensional(2D) images of three consecutive cardiac cycles were recorded. We used PHILIPS iE33 color ultrasonograph with X3-1 matrix transducer of real time three dimension,the volume 3D were gathered from the LV apical four-chamber view and these data were transferred to Qlab6.0 work station for offline analysis. Endocardium were drew automatically five spots at mitral annulus and apex of hear from the LV apical four-chamber view, two-chamber view, system calculated LVEF.With M3S transducer,the 2D gray-scale image of LV apical four-chamber view, two-chamber view, long-axis view and the short-axis views at the levels of mitral annulus,papillary muscle and apex of the LV were recorded and stored respectively, all images were transferred to Qlab6.0 work station for offline analysis. The cross-section of apex of heart is divided 18 segments,the cross-section of short axis is divided 18 segments, the software algorithm segmented the LV long axis into 18 segments meanwhile short axis into 16 equidistant segments. Peak systolic circumferential strain(Cs), peak systolic radial strain(Rs), the LV twist (LVtw) were measured from short axis, peak systolic (Ls) were measured from long axis. 18 segments'average value of LV long axis's strain was global longitudinal strain(GLs), 16 segments'average value of LV short axis's strain was global circumferential strain(GCs),global radial strain(GRs). LV twist was defined as apical rotation relative to the base. MAD was obtained from LV apical four-chamber view by making the three site of mitral valve ring and apex of heart.Result: (1) Repeatability test:The intra-observer coefficient of differentiation of LVEF was 9.0%,the inter-observer was 12.1%; The intra-observer coefficient of differentiation of MAD was 8.1%,the inter-observer was 10.1%. (2) The relation of LV global strain and twist with LVEF: LVEF was correlated with GLs, GRs, GCs, LVtw significantly (r=-0.75,0.52,-0.51and0.61respectively,P < 0.01). Multi-variant regression analysis indicated that GLs and GCs were the independent predictors of LVEF (beta=-0.66and -0.35,respectively),LVEF=23.74-1.12GLS-0.85GCs (P<0.01). (3) The relation of LV global strain and twist with MAD: A good correlation was showed between MAD and GLs, GRs,and LVtw (r=-0.73, 0.47and0.46respectively,P<0.01)but a weak correlations with GCs (r=-0.35,P<0.05). GLs was the independent predictor of MAD,MAD=3.35-0.55GLs(P<0.01). (4) An excellent correlation was found between MAD and LVEF (r=0.84,P<0.01),LVEF=39.05+1.88MAD(P<0.01).Conclusion: MAD showed a novel correlation with LVEF, and with its simplicity and accuracy, MAD may be a new promising modality to evaluate the global systolic function of left ventricle for clinical routine practice.Part II Evaluation of left ventricular systolic function in patients with dilated cardiomyopathy by two-dimensional speckle tracking imagingObjective: To determine the feasibility and the accuracy of mitral annulus displacement by speckle tracking imaging (MAD) to evaluate the global function of the left ventricle in patients with dilated cardiomyopathy(DCM).Methods: The study population consisted of 20 DCM, male 5, female 15, average age 40±15 years, the whole subjects conforms to WHO to diagnose the standard about DCM. 36 healthy subjects, male 21, female 15, average age 38.4±15.4 years. We used PHILIPS iE33 color ultrasonograph with X3-1 matrix transducer of real time three dimension, the volume 3D were gathered from the LV apical four-chamber view and these data were transferred to Qlab6.0 work station for offline analysis.Endocardium were drew automatically five spots at mitral annulus and apex of hear from the LV apical four-chamber view, two-chamber view, system calculated LVEF. With M3S transducer, the 2D gray-scale image of standard LV long-axis view and the short-axis views were recorded and stored respectively, all images were transferred to Qlab6.0 work station for offline analysis, the following parameters were obtained, the global peak systolic longitudinal strain (GLs), circumferential strain (GCs), radial strain (GRs) and the left ventricular twist (LVtw).LV twist was defined as apical rotation relative to the base. MAD was obtained from LV apical four-chamber view by making the three site of mitral valve ring and apex of heart.Result: (1) The curve shape longitudinal strain,circumferential strain and radial were disorder in DCM group, its strain peak value loses change regularity compared with the control group. The parameters in DCM group were significantly lower than those in the healthy subjects(P<0.01=. (2) In the control group, LVEF was correlated with GLs, GRs, GCs, LVtw significantly(r = -0.75,0.52,-0.51 and 0.61 respectively,P < 0.01 = . Multi-variant regression analysis indicated that GLs and GCs were the independent predictors of LVEF (beta = -0.66 and -0.35,respectively), LVEF=23.74-1.12GLS-0.85GCs(P<0.01).In DCM group, LVEF was correlated with GLs, GRs, GCs, LVtw too(P<0.01), GLs and GCs were the independent predictors of LVEF (beta=-0.53 and -0.43, P<0.01,respectively). LVEF=2.0-1.7GLS-1.3GCs. (3) In the control group, a good correlation was showed between MAD and GLs,GCs,GRs, and LVtw(P<0.01), GLs was the independent predictors of MAD, MAD=3.4-0.6GLs; In DCM group, MAD was correlated with GLs, GCs, GRs, and LVtw(P<0.01), GLs and LVtw were the independent predictors of MAD(beta=-0.52and-0.42, P<0.01, respectively), MAD=0.6-0.3GLs+0.6LVtw. (4) In the control group an excellent correlation was found between MAD and LVEF (r=0.84,P<0.01), LVEF=39.05+1.88MAD(P<0.01); In DCM group, an excellent correlation was found between MAD and LVEF (r=0.91,P<0.01), LVEF=0.05+4.5MAD. The cut-off value of TMAD for LVEF≤50% was 8.9mm with a sensitivity of 100% and a specificity of 95% .Conclusion: Using STI the technical appraisal DCM patient LV global function, indicated that the MAD has not only reflected the myocard longitudinal movement, moreover reflected the LV whole motion. MAD showed a novel correlation with LVEF and with its simplicity and accuracy,MAD may be a new promising modality to evaluate the global systolic function of left ventricle for clinical routine practice.Part III Evaluation of left ventricular systolic function in patients with hypertension by two-dimensional speckle tracking imagingObjective: To determine the feasibility and the accuracy of mitral annulus displacement by speckle tracking imaging (MAD) to evaluate the global function of the left ventricle Reconstitution in patients with hypertension.Methods: 40 patients with essential hypertension (male 21,female 19, average age50.9±15.3years), 30 age- and gender- matched healthy volunteers (male 16,female 14, average age 48.4±17.3 years) as the control group. All hypertension patients were divided into two groups according to left ventricular mass index (LVMI)and relative wall thickness(RWT);①left ventricle normal geometric, LVN,20 patients, male LVMI≤116g/m2, female LVMI≤109g/m2, RWT≤0.42;②left ventricle remodeling, LVR, including concentric restructure (LVMI in normal range, the RWT>0.42,10), the concentric hypertrophy (LVMI and RWT surpasses normal range,8) and eccentric hypertrophy (LVMI surpasses normal range, RWT≤0.42,2). The advance echocardiographic examination were performed and some paremeters were acquired, including diastolic interventricular septal thickness (IVSTd), diastolic posterior wall thickness(LVPWTd), left ventricular end-diastolic diameter(LVEDd). The application formula calculates LVM, LVMI, RWT. With the tissue speckle tracking imaging, the following parameters were obtained using a Qlab 6.0 workstation: MAD, the global peak systolic longitudinal strain (GLs), circumferential strain (GCs), radial strain (GRs) and the left ventricular twist (LVtw). The left ventricular ejectionfraction (LVEF) was calculated based on real time three-dimension echocardiography. The difference of these parameters between control group andLVN,LVAgroup was compared and the correlation between MAD, LVEF, GLs, GCs, GRs and LVtw were analyzed respectively.Result: (1) The parameters except LVtw were significantly lower in LVR group than those of the control group(P<0.01) while there was no significant difference in LVN group; LVtw were significantly lower in LVR and LVN group than those of the control group (P<0.01). (2) A good correlation was showed between MAD and LVEF in LVNandLVA group and the control group(control group:r=0.84, LVEF=39.15+1.90MAD; LVN group:r=0.83, LVEF=12.96+3.85MAD; LVR group:r=0.76, LVEF=35.36+2.41MAD, respectively). (3) In the three group, LVEF was correlated with GLs, GRs, GCs, LVtw significantly. Multi-variant regression analysis indicated that GLs and GCs were the independent predictors of LVEF in control group(beta=-0.66and-0.35,P<0.01,respectively, LVEF=23.7-1.1GLS-0.85GCs), GLs was the independent predictors of LVEF in LVN group(beta=-0.73, P<0.01, LVEF=25.63-2.13GLs), GCs and LVtw were the independent predictors of LVEF in LVR group(beta=-0.40 and 0.47, P<0.01, respectively, LVEF=30.29+1.60LVtw-0.59GCs). (4) A good correlation was showed between MAD and GLs, GRs, GCs and LVtw in three group, GLs was the independent predictor of MAD(control group: MAD=3.4-0.6GLs; LVN group:MAD=5.59-0.44GLs;LVR group: MAD=3.41-0.56GLs,P<0.01, respectively).Conclusion: The global function of the left ventricular remodeling in patients with hypertension could be assessed by using STI, and MAD may be an easy and simple method for evaluation of the global systolic function of remodeling the left ventricle.