Two-dimensional speckle tracking echocardiography for the assessment of atrial function

Echocardiography is the most common diagnostic method for assessing atrial function but the technique has some limitations. Traditionally, assessment of left atrial function has been performed by measuring volumes with 2D echocardiography. Additionally, it can be assessed with transmitral Doppler and pulmonary vein Doppler. Recently, an alternative method has been incorporated, namely, measurement of myocardial deformation with color tissue Doppler-derived strain. However, this method has several limitations, such as suboptimal reproducibility, angle-dependence, signal artifacts and the fact that it only measures regional strain and does not obtain information about the curved portion of the atrial roof. To overcome these limitations in the quantification of atrial function, the use of speckle tracking echocardiography (STE) strain has been proposed. This technique is not derived from Doppler but rather from 2D echocardiography; it is angle-independent and allows one to measure global as well as regional atrial strain. In this editorial, we describe the physical and pathophysiological concepts of STE and underline the clinical usefulness of this new technique.

Evaluation of Left Ventricular Function after Percutaneous Recanalization of Chronic Coronary Occlusions: The Role of Two-Dimensional Speckle Tracking Echocardiography

Background: The recanalization of a chronic total coronary occlusion is the possible way to improve left ventricular (LV) function through the recovery of hibernating myocardium. Aim: The aim of this study is to evaluate the role of 2D speckle tracking in evaluation of the left ventricular (LV) systolic function in chronic total occlusion (CTO) patients before and at 1 day as well as 3 months after percutaneous coronary intervention (PCI). Patients and Methods: A prospective observational study included 40 patients diagnosed with coronary angiography to have a chronic total occlusion. Percutaneous coronary revascularization was performed according to standard practices with the femoral approach. Conventional 2D echocardiography was used to assess LV functions and wall motion abnormalities scoring index (WMAI). Using speckle-tracking echocardiography was to measure global longitudinal strain (GLS) and. Follow-up of patients was done at day 1 and 3 months later after PCI. Results: Forty patients were included in this study, with a mean age of 58.55 ± 7.98 years. GLS and WMAI difference at baseline and follow-up shows a positive correlation with left ventricular ejection fraction (LVEF) changes at baseline and follow-up (p Conclusion: The results of this study provide evidence to support the clinical use of 2D-STE to monitor the early changes of LV function. In patients undergoing CTO revascularization, change in GLS was more sensitive predictors for LV function improvement at 3-month follow-up.

Early prediction of myocardial viability after acute myocardial infarction by two-dimensional speckle tracking imaging

BackgroundIdentifying 心肌的坏死和在尖锐心肌的梗塞(AMI ) 的心肌的生存能力的度的 transmural 程度临床上是重要的。这研究的目的是用二维的点缀追踪估计心肌的生存能力在有 AMI.Methods2D-STI 的病人的成像( 2D-STI )与 AMI 在 30 个病人在主要经皮的冠的干预(一种总线标准)以后在起始的表示，三天，和六个月被执行，谁有左前面的下降冠的动脉(男孩)犯人损害。另外，有最小的 stenotic 损害的 20 个病人(&#x0003c；30% 狭窄) 也在控制组在冠的 angiography 上被包括。在六月 dobutamine， echocardiography 在 LAD 领土的七个片断为生存能力评价被执行。根据墙运动反常的恢复，片断作为可行被分类或 131 个片断全部的 non-viable.ResultsA 是可行的，并且 44 是不能生存的。Multivariate 分析在山峰揭示了可行、不能生存的片断之间的重要差别收缩紧张，山峰在起始的表示的收缩紧张率，和山峰在主要一种总线标准以后的收缩紧张率三天。在这些之中，起始的山峰收缩紧张率为心肌的生存能力有最高预兆的价值(危险比率：31.22， P &#x0003c；0.01 ).Conclusions2D-STI 为估计收缩紧张率可能是的心肌的生存能力，和山峰是可行的在有 AMI 的病人的心肌的生存能力的最可靠的预言者。

Evaluation of the Effect of Sigmoid-Shaped Interventricular Septum on Left Ventricular Systolic Function in Patients with Essential Hypertension by Two-Dimensional Speckle Tracking Echocardiography

Objective: To evaluate left ventricular regional and global systolic function by measuring left ventricular longitudinal strain (LS) in hypertensive patients with sigmoid-shaped interventricular septum (SIS) by two-dimensional speckle tracking (2D-STE);in order to explore whether the sigmoid-shaped interventricular septum affects the left ventricular systolic function in patients with hypertension. Methods: Routine echocardiographic parameters were measured in 30 hypertensive patients with SIS (SIS group) and 30 hypertensive patients without SIS (non-SIS group). The left ventricular segments and global LS were measured by 2D-STE, and the two sets of parameters were compared. Results: The value of the thickness of the basal segment of the interventricular septum (IVSBT), the thickness of the middle segment of the interventricular septum (IVSMT) and the ratio of the basal segment of the ventricular septum to the middle segment of the interventricular septum (IVSBT/IVSMT) in SIS group was higher than that in non-SIS group. However, the value of left ventricular outflow tract diameter (LVOTD) in SIS group was lower than that in non-SIS group. There was a significant difference between the two groups (all P Conclusion: SIS affects left ventricular regional systolic function of patients with hypertension. 2D-STE can early evaluate left ventricular longitudinal systolic function in hypertensive patients with SIS.

Value of two-dimensional speckle tracking imaging in quantitative assessment of left ventricular function in patients with OSAS

Objective: To research the clinical application of two-dimensional speckle tracking imaging (2D-STI) in quantitative assessment of left ventricular function in patients with obstructive sleep apnea-hypopnea syndrome (OSAS). Method: From July 2016 to December 2018, 86 patients with OSAS were selected as OSAS group. According to sleep apnea hypopnea index (AHI), they were divided into mild OSAS group (24 cases), moderate OSAS group (29 cases) and severe OSAS group (33 cases). Another 50 healthy volunteers who underwent physical examination in our hospital during the same period were selected as the control group. The left ventricular function of all patients was quantitatively assessed by 2D-STI. The left ventricular function of all patients was quantitatively assessed by 2D-STI. The results of routine echocardiography and left ventricular global strain parameters of the OSAS group, the control group and the OSAS patients with different severity were compared and analyzed. Result: There were no significant differences in the levels of left ventricular ejection fraction (LVEF), left ventricular end diastolic diameter (LVEDd), left ventricular end systolic diameter (LVESd) between the two groups and OSAS patients with different severity (P>0.05). The levels of IVST, LVPW and LVMI in the OSAS group were significantly higher than those in the control group, the levels of end-diastolic interventricular septal thickness (IVS), left ventricular posterior wall thickness (LVPW), left ventricular mass index (LVMI) in the severe OSAS group were significantly higher than those in the mild and moderate OSAS group, and the levels of IVST, LVPW and LVMI in the moderate OSAS group were significantly higher than those in the mild OSAS group, there were significant differences between groups (P<0.05). The levels of GLS, GRS and GCS in the OSAS group were significantly lower than those in the control group (P<0.05). GLS, GRS and GCS levels in the severe OSAS group were significantly lower than those in the mild OSAS group and the moderate OSAS group, while the levels of global longitudinal strain (GLS), global radial strain (GRS) and global circumferential strain (GCS) in the moderate OSAS group were significantly lower than those in the mild OSAS group (P<0.05). Conclusion: The left ventricular systolic function of OSAS patients is obviously impaired. Left ventricular function in OSAS patients can be assessed timely and accurately by two-dimensional speckle tracking imaging.

Application of three-dimensional speckle tracking technique in measuring left ventricular myocardial function in patients with diabetes

BACKGROUND Diabetic cardiomyopathy is considered as a chronic complication of diabetes mellitus(DM).Therefore,early detection of left ventricular systolic function(LVSF)damage in DM is essential.AIM To explore the use of the three-dimensional speckle tracking technique(3D-STI)for measuring LVSF in DM patients via meta-analysis.METHODS The electronic databases were retrieved from the initial accessible time to 29 April 2023.The current study involved 9 studies,including 970 subjects.We carried out this meta-analysis to estimate myocardial function in DM compared with controls according to myocardial strain attained by 3D-STI.RESULTS Night articles including 970 subjects were included.No significant difference was detected in the left ventricular ejection fraction between the control and the diabetic group(P>0.05),while differences in global longitudinal strain,global circumferential strain,global radial strain,and global area strain were markedly different between the controls and DM patients(all P<0.05).CONCLUSION The 3D-STI could be applied to accurately measure early LVSF damage in patients with DM.

Assessment of Age-related Changes in Left Ventricular Twist by Two-dimensional Ultrasound Speckle Tracking Imaging

To assess the normal value of left ventricular twist （LVtw） and examine the changes with normal aging by 2-dimensional ultrasound speckle-tracking imaging （STI）, 121 healthy volunteers were divided into three age groups： a youth group （19-45 y old）, a middle-age group （46-64 y old ） and an old-age group （≥65 y old）. Basal and apical short-axis images of left ventricular were acquired to analyse LV rotation （LVrot） and LVrot velocity. LVtw and LVtw velocity was defined as apical LVrot and LVrot velocity relative to the base. Peak twist （Ptw）, twist at aortic valve closure （AVCtw）, twist at mitral valve opening （MVOtw）, untwisting rate （UntwR）, half time of untwisting （HTU）, peak twist velocity （PTV）, time to peak twist velocity （TPTV）, peak untwisting velocity （PUV）, time to peak untwisting velocity （TPUV） were separately measured. The results showed that the normal LV performs a wringing motion with a clockwise rotation at the base and a counterclock- wise rotation at the apex （as seen from the apex）. The LVtw velocity showed a systolic counterclockwise twist followed by a diastolic clockwise twist. Peak twist develops near the end of systole （96%±4.2% of systole）. With aging, Ptw, AVCtw, MVOtw, HTU and PUV increased significantly （P〈0.05） and UntwR decreased significantly （P〈0.05）. However, no significant differences in TPUV, PTV and TPTV were noted among the 3 groups （P〉0.05）. It is concluded that LV twist can be measured non-invasively by 2-dimensional ultrasound STI imaging. The age-related changes of LVtw should be fully taken into consideration in the assessment of LV function.

Evaluation of Right Ventricular Global Longitudinal Function in Patients with Tetralogy of Fallot by Two-dimensional Ultrasound Speckle Tracking Imaging

Quantification of right ventricular(RV)volume and function remains a challenge because of RV complex geometry by conventional echocardiography.The purpose of this study was to assess RV global longitudinal function in patients with tetralogy of Fallot(TOF)by 2-dimensional ultrasound speckle tracking imaging(STI).Thirty-eight patients with TOF were enrolled in this study and divided into child group(n=25)and adult group(n=13)according to age.Thirty-eight age-and sex-matched normal subjects were selected as c...

Evaluation of left ventricular systolic dyssynchrony by two-dimensional speckle tracking imaging and real-time three-dimensional echocardiography

Background Two-dimensional speckle tracking imaging （2D-STI） and real-time three-dimensional echocardiography （RT-3DE） have more advantages in evaluating left ventricular （LV） systolic dyssynchrony than traditional echocardiographic techniques. The study aimed to evaluate LV dyssynchrony parameters by both 2D-STI and RT-3DE, and the correlation between these two techniques. Methods A total of 43 chronic heart failure （CHF） patients and 27 healthy volunteers were enrolled. There were 23 dyssynchrony parameters selected to evaluate left ventricular systolic synchronization, involving 15 from 2D-STI and 8 from RT-3DE. Results Few of the dyssynchrony parametersshowednegative correlations with LV ejection fraction （LVEF） in the CHF group. The difference between time to peak-systolic radial strain of the anteroseptal and posterior segments at the level of papillary muscles [AS-P（RS）] from 2D-STI showed positive correlations with parts of the parameters from RT-3DE （P 〈 0.05）. Conclusions LV systolic dysfunction does not correlate with dyssynchrony. Moreover, there is a weak association between 2D-STI and RT-3DE in assessment of left ventricular dyssynchrony.

Value of myocardial function in children with Kawasaki disease by two-dimensional and three-dimensional ultrasound speckle tracking

Objective:To investigate the value of two-dimensional ultrasound speckle tracking(2D-STI)and three-dimensional ultrasound speckle tracking(3D-STI)in evaluating myocardial function in children with Kawasaki disease.Methods 92 children with Kawasaki disease admitted to our hospital from February 2017 to February 2019 were retrospectively analyzed.50 children who underwent 3D-STI examination were taken as observation group and 42 children who underwent 2D-STI examination were taken as control group.The left ventricular systolic function index,storage time and analysis time of the image,the diameter of coronary artery,the strain difference of left ventricular basal segment,middle segment,apical segment and whole segment were observed.Results The levels of left ventricular end-diastolic volume(LVEDV),left ventricular end-systolic volume(LVESV),left ventricular myocardial mass(LVMI)in the observation group were higher than those in the control group(P<0.05),but there was no statistical difference in left ventricular ejection fraction(LVEF)between the two groups(P>0.05).The storage time and analysis time of the image in the observation group were significantly lower than those in the control group(P<0.05).The left coronary artery(LCA)and right coronary artery(RCA)in the observation group were higher than those in the control group(P<0.05).There was no statistical difference between left anterior descending(LAD)in the two groups(P>0.05).The longitudinal peak systolic strain(LS),circumferential peak systolic strain(CS)and radial peak systolic strain(RS)in the observation group were higher than those in the control group(P<0.05).The global longitudinal peak strain(GLS),global circumferential peak strain(GCS)and global radial peak strain(GRS)in the observation group were higher than those in the control group(P<0.05).LS and CS in the middle segment of the observation group were higher than those in the control group(P<0.05).Conclusions Compared with 2D-STI,3D-STI can objectively and accurately reflect the myocardial function of children with Kawasaki disease.

Speckle tracking echocardiography:A new approach to myocardial function

Echocardiography is the most common diagnostic method for assessing cardiac function but some limitations affect this technique.Until now,visual assessment of wall motion and thickening has allowed only a subjective evaluation of myocardial function and requires long-term training.Recently,new echocardiographic techniques have been introduced to evaluate myocardial mechanics.Tissue Doppler imaging(TDI)technique is limited by angle-dependency such that only deformation along the ultrasound beam can be derived from velocities,while myocardium deforms simultaneously in three dimensions.Speckle tracking echocardiography (STE)is a more recent technique that provides a global approach to left ventricular myocardial mechanics,giving information about the three spatial dimensions of cardiac deformation.In this editorial,we describe the physical and pathophysiological concepts of STE,discussing the differences compared to TDI and underlining the pitfalls of this new technique.

Evaluation of Ventricular-vascular Coupling in Patients with Type 2 Diabetes Mellitus Using 2-Dimensional Speckle Tracking Imaging

The elastic and functional coupling of heart and vessels makes the stroke work （SW） of the heart optimal. Speckle tracking imaging （STI） can evaluate the myocardial strain and function. We studied ventricular-vascular coupling in 80 diabetic patients with different systolic function using STI. The patients were divided into two groups according to ejection fraction （EF）： the diabetes mel- litus with normal EF （DMN） group and the diabetes mellitus with abnormal EF （DMA） group. Forty-two volunteers served as control group. The relative wall thickness （RWT）, left ventricular mass index （LVMI）, stroke volume （SV）, SW, rate-pressure product （RPP）, systemic vascular resis- tance index （SVRI）, left ventricular end-systolic elastance （Ees）, effective arterial elasticity （Ea） and ventricular-vascular coupling index （VVI） were measured and calculated by conventional echocardi- ography. The longitudinal strain （LS） at basement （LSBA）, papillary muscle （LSvM） and cardiac apex （LSAv） was assessed with STI. It was found： （A） compared with control group, in DMN and DMA groups, LSBA, LSvM and LSAp decreased, and they were lower in DMA group. （B） VVI, RPP and SVRI increased, and they were higher in DMN group; Ees decreased, and it was lower in DMA group. （C） LSBA, LSpM, and LSAv had negative correlation with VVI. LSAp, RWT, LVMI and SW were independent predictors for VVI. The area under the receiver operating characteristic （ROC） curves was used for identification of DMA and DMN with LSBA, LSpM, and LSAp, and the area under the ROC of LSAp was the largest. This study supports that myocardial LS could reflect the ventricu- lar-vascular coupling. Different segments had an order to “respond to” the state of the coupling, and the cardiac apex might be the earliest.

Ultrasound Speckle Tracking Imaging Contributes to Early Diagnosis of Impaired Left Ventricular Systolic Function in Patients with Type 2 Diabetes Mellitus

To investigate the value of ultrasound speckle tracking imaging （STI） in the assessment of the short-axis and long-axis systolic function of the left ventricle （LV） in patients with type 2 diabetes mellitus （DM）, 100 subjects with normal ejection fraction were studied, including 41 patients with DM only （DM group）, 22 patients with both DM and left ventricular hypertrophy （DH group）, and 37 healthy subjects （control group）. Left ventricle systolic function in the long axis defined as longitudinal strain, and that in the short axis defined as radial strain, apical and basal LV rotations, and LV twist were assessed respectively. The results showed that average peak strain in the long axis at basal, middle and apical levels, and global peak strain were significantly decreased in the patient groups when compared with the control group （P〈0.001 for each）. The parameters in DH group were significantly lower than those in DM group （P〈0.01 for each）. There were no significant differences in average radial peak strain in the short axis at different levels, and global peak strain among the three groups （P〉0.05）. Apical and basal LV rotations, and LV twist were greater in the patient groups than in the control group （P〈0.01 for each）. Basal LV rotation and LV twist were greater in DH group than those in DM group （P〈0.01）. It was concluded that STI may be used to identify early abnormalities in patients with type 2 DM that have normal left ventricular systolic function.

Assessment of Right Ventricular Free Wall Longitudinal Myocardial Deformation Using Speckle Tracking Imaging in Normal Subjects

To assess fight ventficular free wall longitudinal myocardium deformation and examine the changes with normal age by speckle tracking imaging （STI）, myocardial systolic peak strain （ε）, systolic peak strain rate （SRs）, early diastolic peak strain rate （SRe）, late diastolic peak strain rate （SRa）, the ratio of SRe/SRa were measured in the basal, middle and apical segments of right ventficular free wall in 75 healthy volunteers （age range： 21-71 y） by STI from the apical 4-chamber view. RV longitudinal strain and strain rate were highest in the basal segment of the free wall. Older subjects had lower early diastolic strain rate （SRe） than younger subjects, but they had higher late diastolic strain rate （SRa）. A negative correlation between age and the ratio of SRe/SRa was found in all RV free wall segments （r=-4）.466 - -0.614, P〈0.01）. It is concluded that RV diastolic strain rate changes with age and STI can be used for the study of RV myocardial deformation.

Assessment of Left Ventricular Global Twist in Essential Hypertensive Heart by Speckle Tracking Imaging

The left ventricular twist was evaluated by 2-dimensional ultrasound speckle-tracking imaging （STI） in 50 patients with hypertension with normal geometric left ventricle （LV） and 45 normal subjects as control group. The mean value of LV rotation was obtained at each plane Using STI. LV twist and twist velocity were defined as apical rotation/rotation rate relative to the base respectively. To adjust the intersubject differences in heart rates, the time sequence were normalized. The results showed that peak twist developed near the end of systole. Peak LV twist was significantly higher in patients with hypertension than normal controls （P〈0.001）. The diastolic untwisting mainly occurred in early diastole （=38%）. Compared with normal controls, untwisting rate （Untw R） in patients with hypertension was significantly reduced （P〈0.001）, and untwisting half-time （UHT） was significantly delayed （P〈0.05）. This study demonstrated that STI has a potential ability to evaluate the early change of heart function in patients with hypertension by measuring the twist of LV.

Global and segmental myocardial deformation by 2D speckle tracking compared to visual assessment

AIM:To examine the feasibility and reliability of measuring global and segmental longitudinal strain(LS) compared to visual assessment of wall motion(WM).METHODS:Assessment of segmental(17 left ventricular segments) LS using automatic function imaging(AFI) in 55 patients(60.0 ± 8.7 years,73% male) divided into 2 groups:groupⅠ included 35 patients with WM abnormalities and/or impaired ejection fraction and group Ⅱ included 20 patients with normal WM and ejection fraction.Visual analysis of WM abnormalities was performed using 2-dimensional echocardiography(2DE) and WM score was calculated.Both modalities were analyzed by one expert reader at 2 different sessions.RESULTS:Analysis of 935 left ventricular segments was completed in 94.1% and 96.3% by visual assessment and AFI,respectively.There was a strong positive linear relationship between the WM score and global LS in all patients.Intra-observer agreement for calculation of WM score was excellent for groupⅠ patients(kappa:0.97) and very good for group Ⅱ patients(kappa:0.92).Intra-observer agreement for AFI showed excellent agreement with very small mean difference in both groupⅠ and Ⅱ(-0.0 ± 2.3 and-0.0 ± 1.9,respectively).CONCLUSION:The interpretation of global and segmental LS using AFI is a more feasible and reliable technique for the quantification of myocardial deformation than visual assessment of WM scores.

Assessment of Left Ventricular Radial Deformation by Speckle Tracking Imaging

The left ventricular radial strain in the inner and outer layers was evaluated by using two-dimensional speckle tracking imaging （2DS）. Twenty-five piglets were studied. The short axis views were acquired. Peak systolic radial strain was measured from 6 circumferential points related to 6 standard segments in the inner and outer layers respectively using 2DS methods. The peak positive first derivative （dp/dt） of left ventricular pressure was compared to the radial strain from 2DS. The inner band showed higher peak radial strain values as compared to the outer band at all of the segments （P〈0.0001）, but the differences had significance just in anteroseptal, posterior, inferior and septal segments （P〈0.05）. Good correlation could be found between radial strain of inner and outer layers and peak dp/dt （P〈0.001）. These preliminary results showed that the degree of local deformation or wall thickening of the ventricular wall in its inner layer was more obvious than its outer layer. It is suggested that the 2DS technique is useful and sensitive for better understanding the regional and global myocar- dial motion and its relationship to the complex architecture of myocardium.

Assessment of Aortic Root Mechanics in Hypertensive Patients by Speckle Tracking Echocardiography

Objectives: Hypertension is a major risk factor for several cardiovascular diseases, including stroke, atherosclerosis and coronary heart disease. Remodeling of the aortic root may be expected to occur in hypertensive subjects as a result of increased stress on the aortic wall due to the repeated hemodynamic overload. Two-dimensional speckle tracking echocardiography is a promising new imaging modality. The aim of this study is to assess aortic root mechanics in relation to left ventricular mechanics in hypertensive patients by speckle tracking echocardiography. Methods: The study included 50 individuals, 30 patients with hypertension compared with 20 age and sex matched healthy volunteers as control group. For both groups, conventional echo was done and speckle tracking echocardiography of the LV including longitudinal, circumferential, radial strain, LV rotation and the longitudinal strain of the ascending aorta and aortic distensibility were measured. Results: Aortic longitudinal strain of both anterior and posterior walls, andalso LV longitudinal peak systolic strain were lower significantly in patient group, and also in the same group, the apical rotation was higher than control;aortic longitudinal strain was negatively correlated with E/E, and LV global longitudinal strain was correlated positively with septal annular E wave peak velocity and with aortic distensibility. Conclusion: Hypertension significantly lowers ascending aortic longitudinal strain and the changes are correlated significantly with LV longitudinal systolic function and with echo parameters of elevated LV filling pressure.

Torsional Dynamics and 2D Speckle Tracking in Heart Failure with Reduced Ejection Fraction on Patients Taking Sacubitril/Valsartan and Naive

This study aims to evaluate the torsional dynamics and 2D speckle tracking in heart failure with reduced ejection fraction on patients taking angiotensin receptor neprilysin inhibitors (ARNI) and none.?ARNI has been shown to be superior to enalapril in?the?long term reducing the mortality and hospitalization of heart failure (HF). However short-term effects on diastolic function remain unclear. We sought to evaluate 6 months' effects of ARNI on left ventricular (LV) diastolic parameters determined by speckle tracking and tissue Doppler imaging. This study was carried out in Menoufia University Hospitals including 60 patients of HFrEF during the period from August 2019 to January 2020. (50%) of patients were?treated with traditional treatment of heart failure and the remaining were?treated with ARNI. Data were collected including history and clinical examination. ECG and speckle tracking and tissue Doppler imaging were?done to evaluate the diastolic function. Our results showed no significant difference between the two groups at baseline. There was?a?significant improvement?in?the LV diastolic function parameters. Untwisting?time and untwisting?onset showed the highly significant parameters of improvement. This study concluded that ARNI showed short term improvement of diastolic function of the left ventricle that could be detected by STE.

A Modified Monte Carlo Model of Speckle Tracking of Shear Wave Induced by Acoustic Radiation Force for Acousto-Optic Elasticity Imaging

A modified Monte Carlo model of speckle tracking of shear wave propagation in scattering media is proposed. The established Monte Carlo model mainly concerns the variations of optical electric field and speckle. The two- dimensional intensity distribution and the time evolution of speckles in different probe locations are obtained. The fluctuation of speckle intensity tracks the acoustic-radiation-force shear wave propagation, and especially the reduction of speckle intensity implies attenuation of shear wave. Then, the shear wave velocity is estimated quantitatively on the basis of the time-to-peak algorithm and linear regression processing. The results reveal that a smaller sampling interval yields higher estimation precision and the shear wave velocity is estimated more efficiently by using speckle intensity difference than by using speckle contrast difference according to the estimation error. Hence, the shear wave velocity is estimated to be 2.25 m/s with relatively high accuracy for the estimation error reaches the minimum （0.071）.