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.

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...

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.

Left Ventricular Systolic Strain of the Cardiac Allograft Evaluated with Three-dimensional Speckle Tracking Echocardiography

Three-dimensional speckle tracking echocardiography was employed to evaluate the changes of left ventricular systolic strain in 23 heart transplant recipients at 1 st, 3rd, 6th and 12th month after heart transplantation, and 23 healthy subjects served as controls. The three-dimensional full-volume echocardiographic images of left ventricle were recorded and then were analyzed using EchoPAC software. The strain curves and peak systolic strain values for each segment and overall left ventricular wall were obtained. Left ventricular global peak longitudinal strain （GPSL）, global peak radial strain （GPSR）, global peak circumferential strain （GPSC） and global peak area strain （GPSA） were measured and then statistically analyzed. There were no significant differences in left ventricular ejection fraction （LVEF） and cardiac output （CO） between heart transplant recipients and controls. The GPSL in heart transplant recipients at 1st month after surgery was significantly lower than that in controls, but close to the normal value at 3rd month after surgery and later. The GPSC, GPSA and GPSR were significantly lower in heart transplant recipients at 1 st, 3rd, 6th and 12th month after surgery than those in controls. It is suggested that three-dimensional speckle tracking echocardiography can be used for monitoring changes of left ventricular systolic strains and evaluating left ventricular systolic function in cardiac allograft.

The Value of Speckle Tracking Strain Imaging at Recovery Period of Dobutamine Stress Echocardiography

Background: Dobutamine stress echocardiography (DSE) is a well-established method for detecting myocardial ischemia. The classic echocardiographic findings of ischemia are new or worsening abnormalities of radial wall thickening. However, interpretation of these findings is subjective and dependent on experience. Speckle tracking strain imaging (STI) has been introduced as a novel method to overcome these limitations. Objective: The aim of the study is to evaluate the value of speckle tracking imaging (STI) by estimating the mean global longitudinal systolic (GLS) and the mean global circumferential systolic (GCS) strain imaging at recovery period of dobutamine stress echocardiography for prediction of significant coronary artery disease (CAD) in patients with chest discomfort. Methods: Fifty three patients presented for evaluation of chest discomfort underwent dobutamine stress echocardiography and coronary angiography at Cardiology Department,Menoufia University Hospital. The mean global left ventricular longitudinal systolic strain (GLS) at apical views—3 chambers, 4 chambers & 2 chambers apical views and global left ventricular circumferential systolic strain (GCS) at short axis view at level of papillary muscle were measured at rest and during recovery period of dobutamine stress echocardiography using automated functional imaging (AFI). Coronary angiography was done for all patients. Significant coronary artery lesion was defined as having a ≥ 70% diameter stenosis on coronary angiography. Patients were divided into two groups based on the presence or absence of significant coronary artery lesion into CAD positive (+ve) group vs. CAD negative (-ve) group. Results: In both groups,there were no statistically significant differences in the clinical characteristics and baseline conventional transthoracic echocardiography. GLS and GSC at recovery were lower in the CAD (+ve) group than in the CAD (-ve) group (-16.69% ± 1.10% vs -19.05% ± 1.41% p ). GLS and GCS during recovery period of DSE were valuable for prediction of CAD when cutoff at recovery is less than -17.95% (sensitivity of 84% & specificity of 84%) for GLS and less than -20.2% (sensitivity of 76% & specificity of 84%) for GCS. Also, we observed that the GLS and GCS percentile decreased from baseline to recovery period of DSE by about -9.95% ± 4.82% and -7.72% ± 3.90% respectively. Conclusion: Speckle tracking Imaging GLS and GCS at recovery period of Dobutamine Stress Echocardiography is feasible and offers an objective technique for prediction of significant coronary artery disease with increasing the accuracy of DSE in patient with chest discomfort.

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 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.

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.

Evaluation of Left Ventricular Rotation and Twist Using Speckle Tracking Imaging in Patients with Atrial Septal Defect

Speckle tracking imaging （STI） was employed to investigate the effect of right ventricular （RV） volume and pressure overload on left ventricular （LV） rotation and twist in 35 patients with atrial septal defect （ASD）, 18 of which with pulmonary hypertension, and 21 healthy subjects serving as controls. The peak rotations of 6 segments at the basal and apical short-axises and the average peak rotation and interval time of the 6 segments in the opposite direction during early systolic phase were measured respectively. LV twist versus time profile was drawn and the peak twist and time to peak twist were calculated. LV ejection fraction （EF） was measured by Biplane Simpson. Compared to ASD patients without pulmonary hypertension and healthy subjects, the peak rotations of posterior, inferior and postsept walls at the basal level were lower （P〈0.05）, and the average counterclockwise peak rotation of 6 segments at the basal level during early systolic phase was higher （P〈0.05）, and the average interval time was delayed （P〈0.05）. LV peak twist was also lower （P〈0.05）, and had a significant negative correlation with pulmonary arterial systolic pressure （r=-0.57, P=0.001）. No significant differences were found in LVEF among the three groups. It was suggested that although RV volume overload due to ASD has no significant effects on LV rotation and twist, LV peak twist is lower in ASD patients with pulmonary hypertension. Thus LV twist may serve as a new indicator of the presence of pulmonary hypertension in ASD patients.

Association between Pentraxin-3 and Cardiac Troponin-I with Left Ventricular Systolic Function in Patients with Anterior ST-Segment Elevation Myocardial Infarction: Evaluation by Speckle Tracking Echocardiography

Background: Pentraxin 3 is an inflammatory biomarker whose serum level is increased during acute myocardial infarction (AMI). The aim of this study was to measure the serum pentraxin-3 level in anterior ST-segment elevation myocardial infarction (STEMI), to investigate correlation with the left ventricular (LV) systolic function assessed by speckle tracking echocardiography, and compare with the well-established cardiac biomarkers of myocardial injury such as troponin-I. Methods: Serum pentraxin-3 level was measured by ELISA in 50 patients with anterior STEMI. LV strain was measured by speckle tracking echocardiography. The results were compared to twenty sex- and age-matched persons who had history of stable angina and normal LV ejection fraction (LVEF). Results: Serum level of pentraxin-3 was significantly higher in STEMI patients in comparison to the control group (8.3 ± 3.1 versus 3.4 ± 1.2 ng/ml, p 0.001). Average LV global longitudinal strain (GLS) was reduced in STEMI patients in comparison to control subjects (11.2 ± 2.4 versus 20.2 ± 2.1, p 0.001). In addition, there was a significant negative correlation between serum pentraxin-3 level and LVEF (r = -0.557, p 0.001) and the average LVGLS (r =-0.529, p 0.001). Serum pentraxin-3 cutoff value > 8.3 ng/ml had sensitivity of 81.8% and specificity of 86.4% to detect LVEF less than 50% (p 0.001). While, peak cardiac troponin-I level > 34 ng/ml was 86% sensitive to detect LVEF less than 50% with specificity of 90.9%. Conclusions: The elevated serum level of pentraxin-3 and cardiac troponin-I in STEMI patients and their association with both LVEF and GLS support the concept that the magnitude of these biomarkers correlates to the severity of myocardium injury.

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.

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.

Speckle Tracking Echocardiography Identifies Impaired Longitudinal Strain as a Common Deficit in Various Cardiac Diseases

The use of speckle-tracking echocardiography(STE)is becoming an increasingly useful tool in the evaluation of myocardial disease.STE software can track the motion of the specular pattern created by the interference of ultrasound with the myofibers of the heart and provide a quantitative means to evaluate subtle changes in ventricular function that often occur before changes in ventricular ejection fraction are observed.STE is most often used to measure the change in shape(strain)of myocardial segments in the circumferential,radial,and longitudinal directions.In various diseases,including coronary artery disease,aortic stenosis,and mitral regurgitation,deficits in longitudinal strain appear to occur earlier than deficits in other measures of strain or in ejection fraction.Consideration of STE measures of left ventricular contraction has the potential to significantly affect clinical management and outcomes of ischemic and valvular heart disease given the ability to separate those with asymptomatic disease who may benefit from earlier interventions than current guidelines may suggest.

Comprehensive Left Ventricular Mechanics Analysis by Speckle Tracking Echocardiography in COVID-19

Background: Cardiac involvement and the consequences of inflammation induced by SARS-CoV2 infection could have catastrophic long-term consequences. Left ventricular mechanics could identify a specific pattern of myocardial fiber damage in patients infected with COVID-19. To our knowledge there are no publications referring to the global description of ventricular mechanics in patients with COVID-19. Objective: To describe left ventricular mechanics in hospitalized patients with COVID-19. Methods: In this cross-sectional study, we included 40 hospitalized patients with confirmed diagnostic of COVID-19, from April 11, 2020, to September 6, 2020. Demographic and laboratory data, clinical and echocardiographic characteristics were collected, as well as events during hospitalization. Left ventricular deformation was analyzed and reported. Results: Subclinical dysfunction was observed in 82.5% (left ventricular longitudinal strain [LVGLS] -17.05% and global circumferential strain [GCS] -18.6%) of the patients, likewise, the mean twist and apical rotation were preserved, and even increased as part of the compensating mechanism to maintain the ejection fraction. Conclusion: In patients hospitalized with COVID-19, despite having a normal left ventricular ejection fraction, subclinical myocardial damage was found, manifested by a decrease in Global Longitudinal Strain (GLS) and Global Circumferential Strain (GCS). This behavior is similar to that of cardiomyopathies in the early stage of the disease, and given the pathophysiological mechanisms involved in the disease, its long-term consequences should be monitored and evaluated.

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.

Newer echocardiographic techniques for aortic-valve imaging: Clinical aids today, clinical practice tomorrow

Increasing life expectancy is expected to lead to a corresponding increase in the prevalence of aortic valve disease(AVD). Further, the number of indications for transcatheter aortic valve replacement(TAVR) as a treatment option for AVD is expanding, with a growing role for echocardiography in its management. In this review we summarize the current literature on some newer echocardiographic modalities and the parameters they generate, with a particular focus on their prognostic and clinical value beyond conventional methods in the management of aortic stenosis, TAVR, and aortic regurgitation. Speckle tracking and 3 D echocardiography are now increasingly being used in the management of AVD. For instance, global longitudinal strain, the beststudied speckle tracking echocardiographic parameter, can detect subtle subclinical cardiac dysfunction in patients with AVD that is not apparent using traditional echocardiographic techniques. The emerging technique of 3D full volume color Doppler echocardiography provides more accurate measurement of the severity of aortic regurgitation than 2D-proximal isovelocity surface area. These novel techniques are promising for evaluating and risk stratifying patients to optimize surgical interventions, predict recovery, and improve clinical outcomes.

Assessment of left ventricular torsion in patients with anterior wall myocardial infarction before and after revascularization using speckle tracking imaging

Background Rotation of the left ventricular （LV） apex to the base, or LV torsion, is related to myocardial contractility and structure and has recently been recognized as a sensitive indicator of cardiac performance, but it has been difficult to measure. The recent development of 2-dimensional （2D） speckle tracking imaging （STI） may provide a powerful means of assessing LV torsion. This study was conducted to evaluate the global and regional LV twist in patients with anterior wall myocardial infarction （AMI） disease before and after revascularization by STI. Methods 2D STI was performed in 35 AMI patients before and one month after revascularization, as well as in 32 normal controls. Left ventricular global and regional rotations were obtained at basal and apical short-axis levels; LV torsion was defined as apical rotation relative to the base. The time sequences were normalized to the percentage of systolic and diastolic duration. Results Before revascularization, LV peak regional and global torsion in patients with AMI were significantly reduced as the result of reduced apical and basal rotation relative to those of normal control group （all P〈0.001）; most significantly in the anterior and anterior-septal regions （P 〈0.001）; one month after revascularization, there were significant changes in peak rotation at either the base or apex relative to pre-revascularization values （all P 〈0.001）. Similarly, peak regional and global LV torsion were increased significantly （all P 〈0.001）. Global torsion inversely correlated with EDV （r=-0.605, P=0.028） and ESV （r=-0.638, P=0.019）; and positively correlated with LVEF （r=0.630, P=-0.021）. Tight relations were also found between torsion and LV longitudinal and short axis function. Conclusions Systolic torsion was decreased in AMI patients. Revascularization therapy can improve the LV function of the AMI patients. STI has a potential to quantify left ventricular global and segment torsion in patients with AMI, and may make the assessment more available in clinical and research cardiology.

Mechanical dyssynchrony and deformation imaging in patients with functional mitral regurgitation

Chronic functional mitral regurgitation(FMR) is a frequent finding of ischemic heart disease and dilated cardiomyopathy(DCM), associated with unfavourable prognosis. Several pathophysiologic mechanisms are involved in FMR, such as annular dilatation and dysfunction, left ventricle(LV) remodeling, dysfunction and dyssynchrony, papillary muscles displacement and dyssynchrony. The best therapeutic choice for FMR is still debated. When optimal medical treatment has already been set, a further option for cardiac resynchronization therapy(CRT) and/or surgical correction should be considered. CRT is able to contrast most of the pathophysiologic determinants of FMR by minimizing LV dyssynchrony through different mechanisms: Increasing closing forces, reducing tethering forces, reshaping annular geometry and function, correcting diastolic MR. Deformation imaging in terms of two-dimensional speckle tracking has been validated for LV dyssynchrony assessment. Radial speckle tracking and three-dimensional strain analysis appear to be the best methods to quantify intraventricular delay and to predict CRT-responders. Speckle-tracking echocardiography in patients with mitral valve regurgitation has been usually proposed for the assessment of LV and left atrial function. However it has also revealed a fundamental role of intraventricular dyssynchrony in determining FMR especially in DCM, rather than in ischemic cardiomyopathy in which MR severity seems to be more related to mitral valve deformation indexes. Furthermore speckle tracking allows the assessment of papillary muscle dyssynchrony. Therefore this technique can help to identify optimal candidates to CRT that will probably demonstrate a reduction in FMR degree and thus will experience a better outcome.

Role of speckle tracking imaging in the assessment of myocardial regional ventricular function in experimental blunt cardiac injury

Purpose： To evaluate the usefulness and information collecting ability of speckle tracking imaging techniques in the assessment of myocardial regional ventricular contractility in a rabbit model with blunt cardiac injury. Methods： Fifteen healthy New Zealand rabbits weighing （2.70 ± 0.28） kg were anesthetized （3% pentobarbital sodium/i.v） and impacted using the BIM-II biological impact machine to induce myocardial contusion （MC）. Hemodynamic parameters, such as heart rate, systolic pressure, mean arterial pressure, diastolic pressure and central venous pressure, were determined before and after MC. Further, param- eters reflecting left ventricular functions, such as left ventricular end systolic pressure, left ventricular end diastolic pressure, isovolumic pressure （IP） and the maximal increasing/decreasing rate of left intraventricular pressure （±dp/dtmax）, were also determined before and after MC. Left ventricular functions were determined either by two dimensional transthoracic echocardiography or by speckle tracking imaging for segmental abnormal ventricular wall motions. Results： Heart rate, systolic pressure, diastolic pressure and mean arterial pressure decreased signifi- cantly but transiently, while central venous pressure markedly increased after MC. In contrast to significant changes in diastolic functions, there was no significant change in cardiac systolic functions after MC. The speckle tracking imaging demonstrated that strain values of different myocardial segment significantly decreased post impact, and that of the ventricular segment decreased from segment to segment. Conclusion： Speckle tracking imaging is useful and informative to assess myocardial regional dysfunctions post MC.