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Objective:To evaluate the left ventricular rotation and twist in patients with constrictive pericarditis (CP) after pericardiectomy by using speckle tracking echocardiography (STE), and observe its trend over time.Methods:A total of 29 patients with CP from Department of Medical Ultrasound, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology from September 2014 to December 2017 underwent echocardiography 1 week before and 1 month, 6 months, 12 months after pericardiectomy. STE was performed to obtain peak values of basal and apical rotation and left ventricular twist. Twenty-nine healthy subjects were recruited as controls in the same period.Results:The left ventricu1ar apical rotation[before surgery(6.62±3.19)°, 1 month after surgery(7.07±4.02)°, 6 months after surgery(7.88±4.46)°, 12 months after surgery(7.85±4.51)°], the left ventricu1ar twist [before surgery(10.50±4.94)°, 1 month after surgery(9.42±5.40)°, 6 months after surgery(9.59±4.62)°, 12 months after surgery(9.70±4.45)°] were significantly lower in patients with CP than those in controls [(11.22±5.17)°, (16.35±5.21)°](all P<0.05); while basal rotation in patients with CP after surgery among different time points were all significantly lower than those in controls[1 month after surgery(-3.85±3.20)°, 6 months after surgery(-3.49±2.09)°, 12 months after surgery(-3.53±2.01)°; controls(-5.57±2.78)°] (all P<0.05), with no significant difference between patients with CP before surgery (-5.22±3.14)° and controls (-5.57±2.78)°( P>0.05). There were no significant differences in left ventricular twist, basal and apical rotation in CP groups before and after surgery among different time points (all P>0.05). Conclusions:Although the left ventricular global function of patients with CP in the long postoperative period seems "normal" , the left ventricular twist, basal and apical rotation are still significantly lower than those in controls. STE can be used to assess the changes of left ventricular twist and rotation in patients with CP long-term after pericardiectomy.
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Objective:To investigate the relationship between vulnerability of mouse coronary artery plaque and downstream myocardial perfusion and myocardial strain.Methods:Thirteen ApoE knockout mice with stable coronary plaques (stable plaque group)and 13 ApoE knockout mice with vulnerable coronary plaques(vulnerable plaque group) were selected as the experimental group, and 15 sex- and age-matched C57BL/6 mice with the same genetic background as ApoE mice were chosed as the control group. Myocardial contrast echocardiography (MCE) was carried out to quantify regional myocardial perfusion at rest and during adenosine stress using a Vevo 2100 system (Visual sonics). Replenishment curves of myocardial contrast were obtained, and rates of signal rise (β) and plateau intensity (A) were recorded. MBF was estimated by the product of A and β. Speckle tracking imaging combined with adenosine stress test was used to evaluate the longitudinal strain of left ventricular myocardium in mice. The vulnerability of the plaque was assessed by histopathology in serial tissue sections of proximal and middle left coronary artery according to the previously reported method.Results:There were no significant differences in body weight, heart rate, left ventricular end diastolic volume, left ventricular end systolic volume, left ventricular mass and ejection fraction among the three groups( P>0.05). The levels of serum triglyceride, total cholesterol, high density lipoprotein and low density lipoprotein in stable plaque group and vulnerable plaque group were significantly increased when compared with those in control group (all P<0.05). The pathological results showed that the coronary luminal stenosis rates in the stable plaque group and the vulnerable plaque group were (74.3±4.9)% and (75.5±7.1)% respectively, with no significant difference between the two groups( P>0.05). MBF of the middle anterior septum and left ventricular posterior wall in the experimental groups were significantly decreased when compared with that in the control group both in the resting status and during adenosine stress(all P<0.05). There were no significant differences in the MCE parameters between the stable plaque group and the vulnerable plaque group at rest( P>0.05). However, during adenosine stress, MBF of the vulnerable plaque group was decreased more significantly than that of the stable plaque group ( P<0.05). Compared with the control group, the values of longitudinal strain of the left ventricle in both experimental groups were decreased during resting status, without statistical significance (all P>0.05), but decreased significantly during adenosine stress and with more decrease in the vulnerable plaque group (all P<0.05). Conclusions:For the same degree of coronary artery stenosis in mice, the coronary artery vulnerable plaque group has less downstream myocardial perfusion and myocardial strain than the stable plaque group during adenosine stress. That is, the plaque vulnerability can affect the downstream myocardial perfusion and myocardial strain in the mouse model.
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Objective:To explore the changes of myocardial strain mechanics in healthy rabbits in the physiological condition by using speckle tracking echocardiography (STE) combined with adenosine stress.Methods:Twenty healthy rabbits underwent STE both at rest and during adenosine stress. The dynamic original images of 3 consecutive cardiac cycles of the standard views from the left ventricular (LV) short axis and apical long axis were acquired and analyzed by the Echo PAC workstation. The procedure was performed to obtain LV global longitudinal peak strain, global circumferential peak strain, and global radial peak strain both at rest and during adenosine stress.Results:There were no significant differences in heart rate and LV structural and functional parameters between baseline and adenosine stress ( P>0.05). After adenosine stress, LV global longitudinal peak strain and global circumferential peak strain increased significantly when compared with those at rest ( P<0.001), while LV global radial peak strain did not change significantly( P>0.05). Conclusions:Adenosine stress echocardiography combined with STE can be used to evaluate the characteristics of myocardial strain mechanics in rabbits in the physiological condition. This research provides reference value for the application of adenosine stress echocardiography in rabbit models with cardiovascular disease in future.
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Objective To assess scoliosis in adolescence and adults by three-dimensional ( 3-D ) ultrasound imaging . Methods A commercial available ultrasound instrument with a magnetic sensor system was used for long distance 3-D ultrasound imaging .Specific phantoms were imaged to evaluate the precision of this imaging system . Twenty healthy adults and 20 patients with scoliosis were imaged by 3-D ultrasonography and radiography . The deformity angle of the patients with scoliosis was measured on the reconstructed coronal plane ( C plane) of 3-D ultrasound imaging . The relevance between the curvature measured by ultrasound and the Cobb angles originated by radiography were evaluated . Results There was no significant difference between the angles of the phantom measured by the 3-D ultrasound imaging system and that measured by an angle gauge ( P = 0 .479) . The transverse process ,vertebral arch and acoustic shadow of the central spinous process of spines in healthy adults can be displayed on the reconstructed C plane by 3-D ultrasound imaging . The morphology of scoliosis in all the twenty patients can be observed on the reconstructed C planes ( multi-layers) by 3-D ultrasound imaging ,which accorded well with that observed on radiograph . In 9 patients ,part of the spinal segment could not be totally displayed on one single coronal plane and no additional measurement was carried out . In 11 patients ,all the segments of the spine could be clearly displayed on a single coronal plane and the curvature of scoliosis was then measured . There were no significant differences between the angle measured on 3-D ultrasound imaging and the Cobb angle measured on radiograph( P =0 .974) and the two measurement methods have high correlation( r =0 .991 , P <0 .0001) . Conclusions The commercial available 3-D ultrasound imaging system applied in this study offers a viable method to assess scoliosis in adolescence and adults in a reliable and radiation-free manner .
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Objective To explore the effects of adenosine stress on myocardial perfusion in healthy mice by myocardial contrast echocardiography ( MCE) . Methods MCE was carried out to quantify regional myocardial perfusion at rest and during adenosine stress using a VEVO 2100 system in 26 C57BL/6 mice . Echocardiography images from standardized parasternal long axis and short axis at papillary muscle level were consecutively acquired in real‐time . All dynamic images were recorded for off‐line analysis . Left ventricular myocardial perfusion quantitative parameters were acquired both under resting status and during adenosine stress . Replenishment curves of myocardial contrast were obtained and myocardial blood flow ( MBF) was calculated . Results Twenty‐six experimental animals successfully underwent MCE before and during adenosine stress . T here was no significant difference in heart rate ,left ventricular structure and functional parameters before and during adenosine stress ( all P ＞0 .05) . Rates of signal rise β values which were used to estimate blood velocity of middle anterior septum and posterior wall in left ventricular long‐axis view and anterior wall ,lateral wall ,inferior wall and septal wall in short‐axis view at papillary muscle increased significantly during stress compared with those at rest ( all P ＜0 .05 ) . T here was no significant difference in the plateau intensity A values( all P ＞0 .05 ) . T he MBF in each segment of the myocardium increased significantly during stress compared with those in resting state ( all P ＜0 .05) . Conclusions T he physiological characteristics of myocardial perfusion in mice before and during adenosine stress were preliminarily obtained ,w hich provided a basis for the application of adenosine stress echocardiography in cardiovascular disease models such as coronary heart disease in mice .
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Objective To explore the effects of adenosine stress on myocardial strain in healthy mice by speckle tracking imaging (STI).Methods A high-resolution rodent ultrasound machine Vevo 2100 was used to perform conventional transthoracic echocardiography at baseline and after intravenous infusion of adenosine in 34 C57BL/6 mice.Echocardiography images from standardized parasternal long axis and short axis at papillary muscle level were consecutively acquired in real-time.All dynamic images were recorded for off-line analysis.Left ventricular myocardial mechanical strain parameters were acquired both under resting status and during adenosine stress.Results Thirty-four experimental animals successfully underwent STI before and during adenosine stress. There was no significant difference in heart rate,left ventricular structure and functional parameters between before and after the adenosine stress ( P >0.05).Global peak longitudinal strain value in left ventricular long-axis view was significantly increased during stress compared with those at resting status ( P < 0.05);while there was no significant increase in the global peak circumferential strain and global peak radial strain values in short-axis view at papillary muscle ( P >0.05).Conclusions Myocardial strain is obtained in healthy mice before and after adenosine stress.This provides an evidence to the application of stress echocardiography in mice with coronary heart disease or other cardiovascular disease in the future.
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Objective To assess the reproducibility of contrast-enhanced echocardiography and conventional echocardiography for measurements of left ventricular ejection fraction(LVEF) and left ventricular volume in patients undergoing cancer chemotherapy. Methods One hundred and two patients undergoing cancer chemotherapy were divided into satisfactory image group(36 subjects) and unsatisfactory image group(66 subjects) according to the quality of the recorded images.High frame rate two-dimensional and three-dimensional images were recorded from apical long-axis view,four-chamber view and two-chamber view of left ventricle. Contrast-enhanced echocardiography was performed in the unsatisfactory image group.Two equally experienced examiners measured the LVEF and left ventricular volume in all patients by EchoPac software. Results The reproducibilities of Simpson′s biplane method and 3D full-volume echocardiography were low for measurements of LVEF in unsatisfactory image group ( P < 0.01).But they were improved significantly with contrast-enhanced echocardiography ( P > 0.05 ). The reproducibilities of Simpson′s biplane method and 3D full-volume echocardiography for measurements of left ventricular end-diastolic volume in unsatisfactory image group were also improved by performing contrast-enhanced echocardiography ( P > 0.05). The reproducibilities for measurements of left ventricular end-systolic volume were well in both group.Conclusions The reproducibilities for measurements of LVEF and left ventricular volume are improved in patients undergoing cancer chemotherapy with unsatisfactory images by using contrast-enhanced echocardiography.
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Objective To develop a probe for photoacoustic imaging and fluorescence imaging targeting integrin αvβ6 . Methods The probe was separated by RP‐HPLC .Molecular weight and the maximum absorption wavelength of the probe were detected by mass spectrum instrument and optical spectrum instrument . Various concentrations of the probe were detected by photoacoustic imaging and fluorescence imaging . The stability of the probe was evaluated when exposed under laser . Targeting of the probe on integrinαvβ6 was evaluated in cell uptake assay with integrinαvβ6 positive and negative cells . The minimum number of cells that could be detected by photoacoustic imaging and fluorescence imaging was also evaluated . Results The probe ICG‐peptide was separated from reaction mixture by RP‐HPLC .The probe had a retention time of 21 .4 minutes and m/z of 4 727 . The labeling ratio of the probe was 1∶1 . The maximum absorption wavelength of the probe was 790 nm . The photoacoustic signal was linearly dependent on the concentration of the probe . The fluorescence signal was linearly dependent on the concentration of the probe when the concentration was smaller than 1 .5 × 10 -5 mol/L . The lowest concentration of the probe that could be detected above the background by photoacoustic imaging and fluorescence imaging was 0 .09 × 10-5 mol/L and 0 .05 × 10-5 mol/L ,respectively . No obvious decrease of the photoacoustic signal was observed after the probe was scanned 20 times ( each time lasted for 1 min) by laser . There existed differences ( P <0 .001) in cell uptake of the probe with various concentrations and reaction time between A431 cells (αvβ6 positive) and 293T cells (αvβ6 negative) . Cell uptake was inhibited by the addition of 5μmol/L unlabeled peptide in A431 cells ( P = 0 .001 ) . The lowest number of the labeled A431 cells detected by photoacoustic imaging and fluorescence imaging was 0 .4 × 106 and 0 .05 × 106 ,respectively . Conclusions The dual functional photoacoustic and fluorescence probe targeting integrin αvβ6 was successfully developed . The targeting and sensitivity of the probe makes it potentially useful in early detection of αvβ6 positive tumors .
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ObjectiveTo analyze the characteristics of left ventricular (LV) twist and discuss the relationship between LV ejection fraction (LVEF) and LV twist in patients with chronic kidney disease (CKD) by two-dimensional speckle tracking imaging (2D-STI).MethodsForty-six patients with CKD and 30 healthy controls were enrolled in this study. After conventional echocardiography, LV end-diastolic volume (LVEDV) and LV end-systolic volume (LVESV) were measured by Biplane Simpson method and the LVEF was calculated. And relevant parameters of LV rotation and twist were measured by speckle tracking imaging. Correlation analysis of LVEDV, LVESV and LV peak rotation and twist were analyzed respectively. ResultsCompared with the control group, LV peak twist and the apical rotation were decreased in CKD patients, which was statistically significant (t=0.002 and 0.020, bothP<0.05). The inferior wall and posterior intermediate septum of basal segment were significantly decreased (t=0.044 and 0.041, both P<0.05). Pearson correlation analysis revealed LV apical peak rotation had a relationship with LVEDV and LVESV (r= 0.355 and 0.409, bothP<0.01).Conclusion2D-STI is an practical noninvasive method which can analyze LV twist accurately and recognize LV systolic dysfunction of CKD patients sensitively.
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Objective To evaluate the changes of left atrial (LA)functions in patients with constrictive pericarditis (CP)after pericardiectomy by two-dimensional speckle tracking echocardiography (STE).Methods A total of 41 patients with CP underwent echocardiography before and after pericardiectomy.The procedure was performed to obtain global LA longitudinal strain,the septal and lateral walls'longitudinal strain,including peak negative strain (NS),peak positive strain (PS),and total strain (TS),using speckle tracking echocardiography.Thirty-five healthy volunteers were recruited as controls. Results After pericardiectomy,global LA peak negative strain and total strain of CP increased significantly (P 0.05).And three components of LA longitudinal strain were still lower than normal (P <0.005).LA lateral wall's total strain,peak positive strain and peak negative strain improved apparently after pericardiectomy (P <0.005),only peak negative strain increased in LA septum (P < 0.01 ).Conclusions In the early postoperative period,LA reservoir and contractile function presented significant improvements,even notable in the lateral area when compared with septum.However,all three parts of LA function were still lower than normal.STE can regionally estimate LA functions in patients with CP after pericardiectomy.
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Objective To assess the systolic function in left ventricular subendocardial myocardium , midmyocardium and subepicardial myocardium in patients with hypertrophic cardiomyopathy (HCM ) by two‐dimensional speckle tracking echocardiography .Methods A total of 32 patients with HCM and 32 healthy adults were included in the study .All standard measurements were obtained from the left ventricular short‐axis views at the levels of mitral annulus ,papillary muscle and apex ,and apical four‐chamber ,two‐chamber ,and long‐axis views .Two‐dimensional speckle tracking imaging was employed .The global peak systolic radial strain ,peak systolic longitudinal strain and circumferential strain of each layer of the left ventricle were measured .Results In patients with HCM and the control group ,the peak systolic longitudinal strain and circumferential strain reduced from subendocardial myocardium to subepicardial myocardium .The global peak systolic radial strain in patients with HCM was significant lower than that in the control group . And in patients with HCM ,peak systolic longitudinal strain in subendocardial myocardium ,midmyocardium and subepicardial myocardium was significant lower than those in the control group .Conclusions Peak systolic longitudinal strain and circumferential strain are reduced from subendocardial myocardium to subepicardial myocardium .Myocardial systolic function is impaired in patients with HCM .In patients with HCM ,longitudinal strain of each layer is lower ,but circumferential strain is mainly reduced in midmyocardium and subepicardial myocardium compared with that in the control group .
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Objective To assess the aorta elastic properties in the procession of atherosclerosis by ultra‐high frequency ultrasound ,and to detect the relationship between the aorta elastic properties and the atherosclerotic plaque burden .Methods Mice deficient for the apolipoprotein E (ApoE‐/‐) with high‐cholestrol diet were studied as an age‐dependent model of atherosclerosis .At 8 ,16 ,24 and 32 weeks of age , the blood pressure in the ascending aorta was measured by catheter ,and the aorta mechanical properties were assessed by measuring aortic elastic modulus of the ascending aorta with ultra‐high frequency ultrasound .The plaque burden was assessed by high‐frequency ultrasound and Masson′s trichrome stain , separately .Results Vessel thickness at the lesion‐prone sites of the lesser curvature of the aorta and the proximal brachiocephalic artery increased with age ,consistent with the Masson′s trichrome staining which showed age‐dependent worsening of atherosclerosis in the mice model .Elastic modulus of the aorta significantly increased from 8 to 32 weeks of age in E‐/‐mice .There was a statistically difference between any two groups .Conclusions With the progression of atherosclerosis and the increased plaque burden ,aorta mechanical properties deteriorated in Apo E‐/‐mice .Ultra‐high frequency ultrasound was a potential tool for assessment of plaque burden and aorta mechanical properties in mouse model .
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Objective To evaluate the left ventricular rotation and twist in the cardiac allograft by speckle tracking echocardiography.Methods Twenty-six heart transplant recipients underwent echocardiographic studies at 1st,3rd,6th and 12th month after heart transplantation.Twenty-six healthy subjects served as controls.Parasternal basal and apical short-axis images of left ventricle were recorded and then were analyzed using EchoPAC software.The curves of basal and apical rotation and left ventricular twist were obtained,Peak values of basal and apical rotation and left ventricular twist were measured and then statistically analyzed.Results There were no significant differences in left ventricular ejection fraction (LVEF) and fractional shortening (LVFS) between heart transplant recipients and controls (P ＞0.05).The left ventricular twist,apical rotation were significantly lower in heart transplant recipients at 1 st,3rd,6th and 12th month after surgery than those in controls (P ＜0.05) ;while basal rotation in heart transplant recipients had no significant difference when compared with controls (P ＞0.05).The left ventricular twist,apical and basal rotation in heart transplant recipients among 1 st,3rd,6th and 12th month after surgery had no significant difference (P ＞ 0.05).Conclusions Although the LVEF and LVFS of cardiac allograft seemed normal,the left ventricular twist,apical rotation were still significantly lower in heart transplant recipients than those in controls.Speckle tracking echocardiography can be used for accurate assessment of left ventricular twist in heart transplant recipients.
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Objective To evaluate global left ventricular(LV) strain of patients with chronic renal failure(CRF) by three-dimensional speckle tracking imaging(3D-STI) and discuss the possible association between global peak strain and ejection fraction of LV.Methods The study includes 22 patients in the renal failure period,25 patients with uremia (pre-dialysis),and 20 healthy controls.Global peak longitudinal strain (GPSL),global peak area strain(GPSA) and global peak radial strain(GPSR) were measured by 3D-STI.Then possible association between GPSL,GPSA,GPSR and LVEF were discussed by the Pearson correlation analysis.Results The GPSL,GPSA,GPSR were statistically different in the control group,patients in the renal failure period and patients with uremia.There were significant differences between groups(F =13.28,4.65,4.68,P ＜ 0.01) as following,all of GPSL,GPSA,GPSR were lower in uremia group compared with control group [q =7.48(GPSL),4.19(GPSA),4.72(GPSR),P ＜0.01],GPSL was lower in renal failure group compared with control group [q =4.9 (GPSL),P ＜0.01].The Pearson correlation analysis revealed GPSL,GPSA,GPSR were strongly associated with LVEF(r =-0.679,-0.781,0.719,P ＜0.01).Conclusions In patients with CRF,the global peak strain can reveal the systolic function of left ventricle and the global peak longitudinal strain can recognize systolic dysfunction more sensitively.
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Objective To investigate left ventricular (LV) strain in patients with hypertension (HT)and myocardial hypertrophy using three-dimensional speckle tracking echocardiography.Methods Myocardial movement was analyzed in 37 primary HT patients with myocardial hypertrophy and 27 healthy volunteers.LV longitudinal,circumferential,radial and area strains were measured.The correlation between each global strain parameter and LV ejection fraction (LVEF) was analyzed.Results LV global longitudinal strain(GSL),global radial strain (GSR) and global area strain (GSA) of HT patients with myocardial hypertrophy were significantly lower than the contrast group,whereas global circumferential strain(GSC) showed no significant difference between the two groups.Longitudinal,radial and area strains were decreased in LV basal and middle levels,while decreased circumferential strain was detected only in basal level.There were significant correlations between LVEF and GSL,GSC,GSR,GSA.Conclusions Impairment of LV regional myocardial contractility can be detected by three-dimensional speckle tracking echocardiography.
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Objective To explore the therapeutic results of percutaneous microwave ablation for patients with recurrence primary liver cancer after surgery and the factors influencing the survival after ablation therapy.Methods 102 patients who underwent hepatectomy for primary liver cancer in April 1998 to December 2010,and subsequent microwave ablation for recurrence hepatocellular carcinoma,were enrolled.Long term survival rates and prognostic factors after ablation were analyzed.Results The 1,3,5,and 7 year overall survival rates after ablation were 73.5％,53.5％,40.5％ and 17.7％.The 1,3,and 5 year overall survival rates for patients within one year recurrence after hepatectomy were 63.3％,38.9％,and 27.1％,respectively,which was significantly lower than that for patients after this time period in which the 1,3,and 5 year overall survival rates were 86.3％,72.3％ and 63.0％,respectively (P =0.003).Univariate analysis revealed that recurrence tumor size more than 3 cm,multiple tumors,poor Child-Pugh score,and AFP level ＞100 μg/L were risk prognostic factors of overall survival for patients who underwent ablation.Multivariate analysis identified multiple tumors,poor Child-Pugh score,and AFP level ＞ 100μg/L were the factors affecting overall survival.Conclusions Microwave ablation is of high clinical application value and is an effective minimally invasive treatment for recurrence hepatocellular carcinoma.Microwave ablation is equally effective when used in late recurrence,single tumor and tumor size≤3 cm.
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Objective To obtain the shear wave velocity(SWV) in breast tumors at different probe orientations.Methods SWV was measured on 92 breast tumors in 48 female patients with the probe placed on transverse,longitudinal and 45 degree planes.Pathological test results were followed up.Results Pathological tests showed benign tumors in 48 patients (92 tumors).Of the three planes,values of the biggest and the smallest SWV showed significant difference (P ＜0.001).Conclusions SWV differs on different planes of breast tumors.So the effect in different probe orientations should be considered using SWV for the differential diagnosis of breast tumors.
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Objective To assess the value of left ventricular (LV) twist and rotation in left-to-right shunt congenital heart diseases(CHD) by two-dimensional speckle tracking imaging(2D-STI).Methods 16 patent ductus arteriosus(PDA),20 ventricular septal defect(VSD) and 36 age,sex matched normal subjects were included.LV end-diastolic volume (LVEDV) and LV end-systolic volume (LVESV) were measured by Biplane Simpson method,then LV ejection fraction (LVEF) was calculated.Two-dimensional images in LV basal and apical short-axis views in three complete cardiac cycles were required.Using speckle tracking imaging,the rotation of 6 segments in basal and apical short-axis levels were measured in CHD patients and control subjects,respectively.Basal and apical rotation versus time profiles and LV twist versus time profiles were drawn.Correlation analysis of LVEDV,LVESV and LV peak twist and rotation were made respectively.Results Compared to the control group,LV peak twist and the apical rotation were increased in CDH patients,which was statistically significant (P ＜0.05).LV peak twist had significant correlation with LVEDV and LVESV.Conclusions LV volume overload which was caused by left-to-right shunt CHD significantly impacted LV twist and apical rotation,but has no significant effect in basal rotation.LV peak twist correlated with LVEDV and LVESV.