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Objective:To investigate the correlations between serum E selectin, intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1) and left ventricular geometry and function in patients with obstructive sleep apnea syndrome (OSAS) combined with prehypertension (pre-HT).Methods:A total of 462 patients with pre-HT and OSAS diagnosed by polysomnography (PSG) in the sleep monitoring unit of the Department of Respiratory and Critical Care Medicine at the First Hospital of Shanxi Medical University from July 2019 to July 2022 were restrospectively analysed, and 52 patients with pure pre-HT (pre-HT group) and 73 patients with pure OSAS (OSAS group) in the same period were selected as the control group. OSAS and pre-HT patients were divided into four groups according to left ventricular geometry: normal geometry (NG) group, concentric remodeling (CR) group, eccentric hypertrophy (EH) group and concentric hypertrophy (CH) group. The general clinical data, PSG parameters, blood biochemical parameters and left ventricular structure and function parameters were compared among the six groups. Pearson correlation and multivariate Logistic regression were used to analyze the correlation between E-selection, ICAM-1, VCAM-1, general clinical data, PSG parameters, blood biochemical parameters with left ventricular geometry and function.Results:①Serum E selectin, ICAM-1, and VCAM-1 concentrations increased sequentially from the NG, CR, and EH to CH groups, with the most significant increase in CH group (all P<0.05). In addition, there were statistically significant differences in age, body mass index (BMI), OSAS severity, neck circumference, waist circumference, systolic blood pressure (SBP), diastolic blood pressure (DBP), Glu, lowest oxygen saturation (Lowest-SaO 2), mean oxygen saturation (Mean-SaO 2), percentage of time with oxygen saturation below 90% of total sleep time (T90), left ventricular end-diastolic diameter (LVEDd), interventricular septal thickness (IVST), left ventricular posterior wall thickness (LVPWT), left ventricular mass index (LVMI), relative ventricular wall thickness (RWT), left ventricular ejection fraction (LVEF), peak mitral early diastolic flow velocity/peak mitral late diastolic flow velocity (E/A), E wave deceleration time (DT), A wave duration (AD), and isovolumic relaxation time (IVRT), and overall long-axis longitudinal strain (GLS) and so on(all P<0.05). ②Pearson correlation analysis showed that E selectin was negatively correlated with LVEF, E/A, e′, E/e′, IVRT, and GLS ( r=-0.236, -0.131, -0.224, -0.215, -0.285, -0.336; all P<0.05). ICAM-1 was negatively correlated with LVEF, E, E/A, e′, IVRT, and GLS( r=-0.130, -0.129, -0.104, -0.351, -0.252, -0.259; all P<0.05). VCAM-1 was negatively correlated with E, e′, and IVRT ( r=-0.132, -0.312, -0.387; all P<0.001). ③Multifactorial logistic regression analysis showed that E selectin and VCAM-1 were independently correlated with EH (β=1.139, OR=3.124, P=0.030; β=1.288, OR=3.626, P<0.001) and with CH (β=1.178, OR=3.248, P=0.013; β=1.108, OR=3.028, P<0.001). Conclusions:E selection and VCAM-1 were independently correlated with hypertrophic left ventricular geometry, suggesting that E selectin and VCAM-1 may be involved in the process of abnormal left ventricular structure and function in patients with OSAS combined with pre-HT.
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En base a la evidencia disponible y a la experiencia de trabajo en la cohorte del estudio GEnotipo, Fenotipo y Ambiente de la HiperTensión arterial en el UruguaY (GEFA-HT-UY) se describe un protocolo "paso a paso" para la adquisición y medición de strain de la aurícula izquierda, tanto de forma global como para un análisis segmentario tipo "ojo de buey", mediante ecocardiografía bidimensional con speckle tracking.
Summary: Based on the available evidence and work experience of the GEnotipo, Fenotipo y Ambiente de la HiperTensión arterial en el UruguaY (GEFA-HT-UY) cohort, a "step by step" protocol for the acquisition and measurement of the left atrial strain is described, both as a global and segmentary analysis ("bull's eye" like ) using two-dimensional speckle tracking echocardiography.
Baseado nos elementos disponíveis e a experiência de trabalhar na coorte do estudo GEnotipo, Fenotipo y Ambiente de la HiperTensión arterial en el UruguaY (GEFA-HT-UY) se descreve um protocolo de "passo a passo" para a aquisição e a medição do strain da aurícula esquerda, tanto em forma global como pra uma análise segmentar tipo "olho de boi", usando a ecocardiografia bidimensional com speckle tracking.
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[Abstract] Objective To investigate the early changes of myocardial systolic and diastolic function in patients with type 2 diabetes mellitus (T2DM) and in patients with both T2DM and coronary heart disease (CAD). Methods A retrospective analysis was taken of 128 patients who were hospitalized for suspected CAD, underwent coronary angiography and received echocardiography between August 2015 and November 2017. In these patients, 32 patients with T2DM with normal coronary angiography (DM group), 66 patients with T2DM and CAD (DM+CAD group) and 30 patients with normal coronary angiography without DM (control group) were enrolled in the study. The two-dimensional speckle tracking strain technique was used to measure the global longitudinal peak strain (GLS) of the left ventricular myocardium, and peak systolic longitudinal strains (PSLS) of the basal segment, middle segment and apical segment of the three groups. The further results were compared and analyzed. Generalized linear regression analysis were taken to analyze the factors affecting left ventricular myocardial GLS in the DM patients. Results The interventricular septal (IVS), left ventricular posterior wall (LVPW) and left artrial dimension (LAD) were increased in the DM group and (DM+CAD group), with the E peak and E/A were decreased, compared with the control group. The peak value and E/e' value were higher in the DM+CAD group, compared with the DM group. Importantly, the left ventricular GLS of the DM group, and the DM+CAD group were significantly lower than that of the control group. Moreover, the left ventricular GLS, the basical, the middle and the apical segment PSLS were all significantly lower in the DM+CAD group, than the DM group. In addition, by generalized linear regression analysis, whether combination of coronary heart disease significantly affected GLS value in DM patients, including glycated hemoglobin levels, hypertension, and E/e' values. Conclusion The DM Patients or the patients of DM+CAD were both have left ventricular systolic and diastolic dysfunction in the early stage, even if the ejection fraction is normal. The left ventricular systolic and diastolic dysfunction is more obviously in the DM+CAD patients. The two-dimensional speckle-tracking strain can be used to evaluate left ventricular diastolic and systolic dysfunction in diabetic patients in the early stage.
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Objective To explore the changes of left ventricular torsion function in patients with latent obstructive hypertrophic cardiomyopathy ( HCM ) ,and provide quantitative informations for clinical evaluation of cardiac function . Methods A total of 49 consecutive patients with HCM without left ventricular outflow tract obstruction at rest were enrolled . All subjects underwent exercise stress echocardiography . After exercise left ventricular outflow tract pressure gradient ( LVO T‐PG ) ≥30 mm Hg was positive for exercise stress test ( latent obstruction) ,w hile LVO T‐PG< 30 mm Hg was negative for exercise stress test ( non‐obstruction) . An ultrasound system obtained two‐dimensional ultrasound images of resting and moving peaks . The global longitudinal strain ( GLS ) ,global circumferential strain ( GCS ) , global radial strain ( GRS) of the left ventricle 16 segments and left ventricular rotation ,twist were analysis using off‐line EchoPAC software . T he differences of the above parameters were compared between the two groups . Results T here were no significant differences in GLS ,GRS ,GCS and Rotation‐B between the two groups in resting and peak period of exercise ( all P > 0 .05 ) ,GRS in both groups were significantly increased compared with that before exercise ( all P < 0 .05 ) . Compared with the negative exercise stress group ,the left ventricular twist and Rotation‐A were significantly increased in resting and peak period of exercise in the positive exercise stress test group( all P <0 .05) . Compared with before exercise ,Rotation‐A and left ventricular twist were significantly decreased in the positive exercise stress test group ( all P <0 .05) ,while no significantly difference was found in the negative exercise stress group ( all P > 0 .05 ) . Conclusions Left ventricular torsion function is significantly changed in rest and after exercise in latent obstructive HCM patients ,providing valuable quantitative information for clinical comprehensive evaluation of cardiac function .
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Global longitudinal strain (GLS) at rest on two-dimensional speckle tracking echocardiography (2D STE) was demonstrated to help detect coronary artery disease (CAD).However,the optimal cut-off point of GLS and its diagnostic power for detecting critical CAD in non-diabetes mellitus (DM) patients are unknown.In the present study,211 patients with suspected CAD were prospectively included,with DM patients excluded.All patients underwent echocardiography and subsequently coronary angiography within 3 days.Left ventricular (LV) GLSs were quantified by 2D STE.Territorial peak systolic longitudinal strains (TLSs) were calculated based on the perfusion territories of the 3-epicardial coronary arteries in a 17-segment LV model.Critical CAD was defined as an area stenosis ≥70% in ≥1 epicardial coronary artery (≥50% in left main coronary artery).Totally 145 patients were diagnosed as having critical CAD by coronary angiography.Significant differences were observed in all strain parameters between patients with and without critical CAD.The area under the receiver operating charcteristic (ROC) curve (AUC) for GLS in the detection of left main (LM) or threevessel CAD was 0.875 at a cut-off value of-19.05% with sensitivity of 78.1% and specificity of 72.7%,which increased to 0.926 after exclusion of apical segments (cut-off value-18.66%;sensitivity 84.4% and specificity 81.8%).The values of TLSs were significantly lower in regions supplied by stenotic arteries than in those by non-stenotic arteries.The AUC for the TLSs to identify critical stenosis of left circumflex (LCX) artery,left anterior descending (LAD) artery and right coronary artery (RCA),in order of diagnostic accuracy,was 0.818 for LCX,0.764 for LAD and 0.723 for RCA,respectively.In conclusion,in non-DM patients with suspected CAD,GLS assessed by 2D STE is an excellent predictor for LM or three-vessel CAD with high diagnostic accuracy,and a higher cut-off point than reported before should be used.Excluding apical segments in the calculation of GLS can further improve the predictive accuracy of GLS.It is unsatisfactory for TLSs to be used to identify stenotic coronary arteries.
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Global longitudinal strain (GLS) at rest on two-dimensional speckle tracking echocardiography (2D STE) was demonstrated to help detect coronary artery disease (CAD).However,the optimal cut-off point of GLS and its diagnostic power for detecting critical CAD in non-diabetes mellitus (DM) patients are unknown.In the present study,211 patients with suspected CAD were prospectively included,with DM patients excluded.All patients underwent echocardiography and subsequently coronary angiography within 3 days.Left ventricular (LV) GLSs were quantified by 2D STE.Territorial peak systolic longitudinal strains (TLSs) were calculated based on the perfusion territories of the 3-epicardial coronary arteries in a 17-segment LV model.Critical CAD was defined as an area stenosis ≥70% in ≥1 epicardial coronary artery (≥50% in left main coronary artery).Totally 145 patients were diagnosed as having critical CAD by coronary angiography.Significant differences were observed in all strain parameters between patients with and without critical CAD.The area under the receiver operating charcteristic (ROC) curve (AUC) for GLS in the detection of left main (LM) or threevessel CAD was 0.875 at a cut-off value of-19.05% with sensitivity of 78.1% and specificity of 72.7%,which increased to 0.926 after exclusion of apical segments (cut-off value-18.66%;sensitivity 84.4% and specificity 81.8%).The values of TLSs were significantly lower in regions supplied by stenotic arteries than in those by non-stenotic arteries.The AUC for the TLSs to identify critical stenosis of left circumflex (LCX) artery,left anterior descending (LAD) artery and right coronary artery (RCA),in order of diagnostic accuracy,was 0.818 for LCX,0.764 for LAD and 0.723 for RCA,respectively.In conclusion,in non-DM patients with suspected CAD,GLS assessed by 2D STE is an excellent predictor for LM or three-vessel CAD with high diagnostic accuracy,and a higher cut-off point than reported before should be used.Excluding apical segments in the calculation of GLS can further improve the predictive accuracy of GLS.It is unsatisfactory for TLSs to be used to identify stenotic coronary arteries.
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Objective Three parameters include circumferential strain (CS),circumferential strain rate (CSr) and stiffness parameter (β) were measured to evaluate the elasticity of carotid artery using two-dimensional(2D) strain imaging and evaluate its clinical value in patients with type 2 diabetes mellitus (T2DM).Methods 60 patients with T2DM were collected and divided into carotid intima-midia thickness (CIMT) thickeness group(34 cases,1.0 mm<CIMT≤1.2 mm) and plaque group(26 case,CIMT> 1.2 mm).33 normal people were supplied as control group.The systolic global peak CS and CSr of the carotid artery were obtained from short-axis view of the common carotid artery and the stiffness parameters β was measured using 2D strain imaging.All the parameters were compared among the three groups.Results The CS and CSr were decreased and β was increased in patients with T2DM (P < 0.01),The CS and CSr obtained from the plaque group were less than that of the CIMT thickeness group(P <0.05),but the β was higher than that of the CIMT thickeness group (P <0.01).The CS and β were correlated significantly with CIMT respectively (r =-0.79,P < 0.01 ; r =0.72,P < 0.01).Conclusions 2D strain imaging is a technique for early assessing the carotid artery elasticity in patients with T2DM,the thicker the CIMT is,the smaller the deformation is and the larger the β is.
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Objective To explore left ventricular longitudinal axis systolic asynchrony by real-time triplane quanti-tativetissue velocity imaging(RT-3PE QTVI) and two-dimensional speckle tracking imaging(STI) in patients with dilated cardiomyopathy. Methods Thirty normal adults were included as the control group and thirty adults with DCM. The images from enough frame rates RT-3PE QTVI and STI were obtained from series long-axis views. Simp-son method was used to measure LVEF. Q-lab software was used to measure peak systolic tissue velocity(Vs) and peak systolic longitudinal strain (Ls),its time to peak point from each segment(Ts,Tls) and the maximal temporal difference of Ts,Tls(Ts-diff,Tls-diff),and the standard deviation of. Ts,Tls(Ts-SD,Tls-SD),which were served as systolic asynchrony indexes in assessing LV longitudinal axis systolic asynchrony. Results ① Compared the con-trol group and DCM group,there were significant differences in LVEDd,LVESd,LVEDL,LVESL,LVEF,FS (P<0.01). ② In comparison with the control group,the Ls and Vs of each segment were decreased in the DCM group (P<0.01). Compared with the control group,the parameters of Tls and Ts in DCM group had obvious ahead or de-layed(P<0.05). ③ Compared with the control group,the parameters of Ts-SD, Tls-SD, Ts-diff, Tls-diff,were significantly different in DCM group (P<0.01). Ts-SD,Tls-SD,Ts-diff,Tls-diff corrrlated negatively to LVEF(r=-0.67,-0.72,-0.75, -0.77,P<0.01). Conclusion The prevalence of left ventricular longitndinal axis systolic asynchrony exits in patients with DCM. There is a better technique to evaluate LV longitudinal axis systolic asynchrony by RT-3PE QTVI and STI than only one.
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ObjectiveTo evaluate regional and global systolic function of left ventricle (LV) after mitral valve replacement(MVR) of different methods by 2-dimensional strain (2DS).MethodsAccording to the operational method whether preserve the posterior leaflet and its subvalvular apparatus,48 patients who underwent MVR were divided into two groups,the preservation group (group A) and the resection group (group B).Echocardiography was examinated before and after MVR and the apical four-chamber view,two-chamber view and long-axis view of LV were acquired.Regional peak strain (Sp) and global strain (GS) of LV longitudinal movement were analysed by 2DS software.Results①Compared to preoperation,the Sp in basal segment of posterior septum and inferior wall and middle segment of lateral wall in group A increased significantly ( P <0.01 or P <0.05).The Sp of group B were improved in both basal and middle segments of posterior septum ( P <0.05),while declined in middle segment of lateral wall and anterior wall,basal segment of lateral wall and apical segment of anterior wall significantly (P <0.01 or P <0.05).②Compared with group A,subtractions between preoperative and postoperative Sp of group B decreased in middle segment and apical segment of anterior wall,middle segment of lateral wall and middle segment of inferior wall significantly ( P <0.01 or P <0.05).③The GS of group A increased significantly ( P <0.05),while that in group B tended to reduce with no statistical significance ( P >0.05).Compared with group A,subtractions between preoperative and postoperative GS of group B droped significantly (P < 0.05).ConclusionsAppropriate preservation of the posterior leaflet and its subvalvular apparatus has morebeneficial effect in improving the early regional and global function of LV after surgery,which would be recommended in MVR.Early regional and global systolic function of LV after MVR could be accurately evaluated by 2DS relatively,which has the application value of guiding clinical treatment and estimating prognosis.
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ObjectiveTo explore the characteristics of left ventricular myocardial function after percutaneous coronary intervention (PCI) in patients with angina pectoris of single-vessel and.multiple-vessel coronary artery disease with two-dimensional strain (2DS).MethodsTotally 63 patients with angina pectoris were divided to single-vessel coronary artery group (n=33) and multiple-vessel coronary artery group (n= 30) based on coronary angiography,and 30 healthy volunteers were enrolled as control group.The two-dimensional images were obtained before and 3 months after PCI,and two-dimensional radial strain was analyzed on GE Echo PAC system.Peak radial strain values of left ventricular basal plane,papillary muscle plane and apical plane during systole were measured.ResultsCompared to control group,left ventricular peak systolic radial strain values decreased in many segments in patients with single-vessel coronary artery group and multiple-vessel coronary artery group before and 3 months after PCI (P<0.05).Totally 136 and 158 left ventricular ischemic segments attained to normal 3 months after PCI in single-vessel coronary artery group (136/185,73.51%) and multiplevessel coronary artery group (158/292,54.11%),respectively (P<0.01).ConclusionThe improvements of peak systolic radial strain are significantly different between angina pectoris patients with single-vessel and multiple-vessels coronary artery disease after PCI.
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Objective To evaluate the value of two-dimensional strain imaging in assessing right ventricular function of recipient fetus in TTTS pregnancies.Methods Sixteen TTTS pregnancies and 19 normal monochorionic diamniotic pregnancies(controls) were included.Doppler studies of the umbilical artery,umbilical vein,ductus venosus,middle cerebral artery,atrioventricular valve and semilunar value were recorded in both fetus,and myocardial performance index of both ventricles was calculated.Longitudinal peak systolic strain of right ventricular were calculated and compared between recipient fetus and other fetus.Results Cardiothoracic ratio and myocardial performance index of right ventricular showed significant differences between recipient fetus and controls.Right ventricular strain was decreased in recipient fetus compared with controls.Conclusions Two-dimensional strain imaging can be used to evaluate right ventricular myocardial function in the recipient fetus of TTTS.
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Objective To investigate the value of high-dose dobutamine stress echocardiography combined with two-dimensional strain imaging in early diagnosis of coronary artery disease. Methods Highdose dobutamine stress echocardiography was performed to 28 patients with suspected coronary artery disease. All wall movements were observed during resting condition and at all stress levels,respectively;the peak systolic longitudinal strain in each endomyocardial segment of left ventricular was measured; the sensitivity and specificity between visual method and two-dimensional strain imaging in diagnosing myocardial ischemia with high-dose dobutamine stress echocardiography were compared. The average peak systolic longitudinal strain was calculated against control group, coronary artery disease group during ischemia segments and non-ischemia segments, and a comparison was made inside each group as well as against the other groups. The area under receiver operating characteristic curve of the peak systolic longitudinal strain was used to predict the sensitivity and the specificity of myocardial ischemia. Results With dobutamine dose of 40 μg·kg-1 · min-1 ,wall motion abnormalities were diagnosed in 6 patients (20 segments) through visual method, myocardial ischemia was found in 15 patients (148 segments) through computing the peak systolic longitudinal strain. Inside the coronary artery disease group during ischemic segments,the majority of peak systolic longitudinal strain was significantly reduced ( P<0.05) compared to the non-ischemic segments and the control group. In diagnosing myocardial ischemia in high-dose dobutamine stress echocardiography, the sensitivity of visual method and two-dimensional strain imaging were 35.3% and 88.2%(P<0.01), specificity 100% and 100%(P>0.05), and accuracy 60.7% and 92.8% (P<0.01). The cutoff value of the peak systolic longitudinal strain was less than or equal to 14.9%, its sensitivity and specificity in predicting myocardial ischemia were 83.3% and 91.7%,respectively. Conclusions High-dose dobutamine stress echocardiography combined with two-dimensional strain imaging can increase the sensitivity of detecting myocardial ischemia and detect concealed myocardial ischemia. High-dose dobutamine stress echocardiography combined with two-dimensional strain imaging can be used in early diagnosis of coronary artery disease.
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Objective To assess global systolic function of left ventricle (LV) using speckle tracking echocardiography in patients who are left volumetric overload and to establish the correlativity between strain and left ventricle end-diastolic volume index (LVEDVI). Methods Seventy-seven patients who were left volumetric overload and 30 normal volunteers were enrolled in this study. Respective 3 high frame rate (> 100 frames/s) 2D images were recorded from the left ventricular short axis views: the levels of mitral valve annulus, papillary muscle and apex. Three global peak systolic radical strain and strain rate were measured using 2D strain imagirg. LVEDV was obtained by two-plane Simpson method and LVEDVI was obtained by normalized LVEDV with surface body area. Patients were divided into 6 groups: transitionalgroup,group A (LVEDVI:90- 120 ml/m2),group B (LVEDVI: 121 - 150 ml/m2 ),group C (LVEDVI:151 -180 ml/m2),group D (LVEDVI: 181 - 210 ml/m2),and group E (LVEDVI>210 ml/m2). Patients were divided into two groups by left ventricular ejection fraction (LVEF): group Ⅰ (LVEF≥ 50 % ), group Ⅱ (LVEF<50%). Results①Compared with normal control group,GRS,GRSr in transitional group showed no change at three short axis levels (P >0.05). The above parameters in group A, B and C were significantly higher than those in normal control group( P <0. 01 ). In transitional group,group A,B and C,GRS, GRSr of three short axis gradually increased with LVEDVI augmentation. Compared with group A, B,C,D and normal control group,the above parameters of 3 short aixs in group E were decreased( P <0. 01 ),which gradually decreased in group C, D, E with LVEDVI augmentation. ②GRS,GRSr of 3 short axis views in group Ⅰ were more significantly high than those in group Ⅱ and normal control group. The parameters above were significantly low in group Ⅱ ( P <0.01). ③In group A,B,C,GRS of papillary muscle and apex levels were correlated positively to LVEDVI ( rpapillary muscle = 0.55,0.64,0.76 and rspex = 0. 74, 0. 79,0.71,P <0.05) ; In group D, there was no correlativity between GRS of papillary muscle and LVEDVI( r =- 0.35, P > 0.05) while negative correlativity was established in apex level( r = - 0.73, P < 0. 05). In group E,the negative correlativity was found between GRS of papillary muscle and LVEDVI( r = -0. 70,P <0.05) while no correlativity was established in apex level( r = - 0.39, P >0. 05). GRS of mitral valve annulus was correlated positively to LVEDVI in group A, B( r = 0.79, 0.77, P < 0.05) and had no correlativity in group C,D. The negative correlativity between them was found in group E( r = - 0. 54, P <0.05). At LVEDVI: 180- 190 ml/m2 ,GRS of papillary muscle and apex level reach the peak point about 93% and 62% ;GRS of mitral valve annulus level reach the peak about 63% at LVEDVI 150 - 160 ml/m2.Conclusions Radial strain,strain rate change periodically with LV volume overload. Wall motion of left ventricle can be evaluated accurately by speckle tracking echocardiography, which provide useful modality for evaluation cardiac systolic function.
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Objective To access the alterations of ischemic myocardial regional motion time caused by different extent of coronary artery stenosis by 2D-strain technique. Methods Two-dimensional images were acquired of the standard parasternal and apical (4-chamber,2-chamber and long-axis) views and short-axis views (mitral annulus, papillary muscle and apex) in 140 patients with coronary artery disease. All left ventricular segments were divided into 5 groups according to coronary stenosis seen on angiography:normal,25% -49% ,50% -74% ,75% -99% and 100%. The time to segmental systolic peak strain, systolic peak strain rate, end systolic strain, early diastolic peak strain rate and late diastolic peak strain rate in longitudinal, radial, circumferential directions and the systolic peak rotation, systolic peak rotation rate, early diastolic rotation rate,late diastolic rotation rate were analyzed with EchoPAC offline software. Results In longitudinal direction,compared with normal group,the time to early diastolic peak strain rate of segments with 75% - 99% coronary stenosis increased significantly, the time to systolic peak strain rate, early diastolic peak strain rate of segments with occluded artery were significantly delayed compared with the other 4 groups (P <0.05). In radial, circumferential directions, the time to systolic peak strain, systolic peak strain rate,late diastolic peak strain rate of segments with 25% - 49% was shorter than that of normal segments. Those indices for segments with 50% - 74% coronary stenosis were delayed compared with segments with 25% - 49% stenosis, however, those for segments with 75% - 99% coronary stenosis showed some improvement in the comparison with segments with 50% - 74% stenosis. All time indices for segments with occluded arteries were delayed ( P <0.05). About rotation, the time to the systolic peak rotation,systolic peak rotation rate,early diastolic peak rotation rate with 25% -49% stenosis was shorter than those of normal segments, the time to systolic peak rotation and early diastolic peak rotation rate for segments with 75% - 99% stenosis improved compared with segments with 50% - 74% stenosis.Conclusions 25% -49% coronary stenosis could lead to alterations of peak myocardial systole and diastole motion time in radial,circumferential and rotation directions,and ≥75% coronary stenosis caused the all 4 directions motion delays. Also the time indices for segments with 75% - 99% coronary stenosis showed some improvement in the comparison with segments with 50% -74% coronary stenosis.
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Objective To investigate the value of left ventricular global two-dimensional strain and strain rate index measured by two-dimensional speckle tracking imaging (2D-STI) in assessing myocardial injury in various degree of rats following acute myocardial infarction. Methods Fifty-five Wistar rats were randomly divided into myocardial infarction(MI) group ( n =45) and sham-operation(SO) group ( n = 10).To establish rats acute myocardial infarction model with different infarct extent, MI group were randomly divided into MI15 group,MI30 group and ML60 group( n = 15,respectively) which underwent occlusion of left anterior descending coronary artery for 15 minutes, 30 minutes and 60 minutes respectively. Echocardiography was performed at baseline and 24 hours after reperfusion. High frame rate twodimensional images were recorded from the left ventricular short-axis views at the papillary muscle level.Left ventricular global circumferential strain(GSc) and strain rate(GSRc) were measured using EchoPAC work station. Left ventricular internal diameter at diastole (LVIDd) and systole ( LVIDs), fractional shortening(FS) and ejection fraction(EF) were measured by anatomical M-model echocardiography. Area of necrosis(AN) of each segment was measured after triphenyl tetrazolium chloride(TTC) staining. Results ① Compared with baseline and SO group, LVIDd and LVIDs of MI15, MI30 and MI60 group significantly increased respectively,whereas FS and EF significantly decreased( P <0. 05). Compared with MI15 group and MI30 group, LVIDd and LVIDs of MI60 group significantly increased, whereas FS and EF significantly decreased(P <0. 05). ② Compared with baseline and SO group,GSc and GSRc of MI15 group, MI30 group and MI60 group significantly decreased. GSc and GSRc of MI group decreased with ischemia duration ( P <0.05). ③ GSc and GSRc significantly correlated with AN respectively ( P <0. 01) while the correlation coefficient was 0. 90 and 0. 88 respectively, and GSc and GSRc were significantly predictors of AN( P <0.01) while the Beta was 0.558 and 0.491 respectively.④AN increased with ischemia duration( P <0.05). Conclusions Left ventricular global circumferential strain and strain rate index measured by 2D-STI,which decreased significantly as the area of necrosis increased, can accurately assess myocardial injury after myocardial infarction in various degree.
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Objective To observe the value of two-dimensional speckle tracking imaging (2D-STI) in assessing regional myocardial viability of rats after acute myocardial infarction. Methods Twenty Wistar rats were randomly divided into acute myocardial infarction group and sham-operation group (each n=10). Echocardiography was performed at baseline and 24 h after reperfusion. High frame rate two-dimensional images were recorded from the left ventricular short-axis views at the papillary muscle level. Peak radial strain (PRS) and peak circumferential strain (PCS) of each segment were measured at systolic period. Left ventricular internal diameter at diastole (LVID_d) and systole (LVID_s), fractional shortening (FS), ejection fraction (EF), wall thickening rate (TR) were measured with anatomical M-model echocardiography. Area of necrosis (AN) of each segment was measured after triphenyl tetrazolium chloride (TTC) staining. Based on TTC staining, ROC curve was used to analyze the accuracy of two-dimensional strain and TR index in identifying infarcted segment. Results ①Compared with acute myocardial infarction group at baseline and sham-operation group after operation, LVID_d and LVID_s of acute myocardial infarction group after operation increased significantly respectively (P50%. Using a cut-off of -6.14%, PCS had a sensitivity of 93.75% and specificity of 90.91% for distinguishing infarcted from viable myocardium. Conclusion 2D-STI can accurately quantify regional myocardial function, providing a sensitive and noninvasive means to assess regional myocardial viability.
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Objective To investigate the consistency of omnidirectional M-mode echocardiography and two-dimensional strain in assessment of left ventricular (LV) radial systolic asynchrony. Methods Thirty patients with heart failure (HF) and 28 healthy volunteers underwent omnidirectional M-mode echocardiography and two-dimensional strain at the same time. The time to peak radial systolic movement (T_m) of LV in 12 segments were measured with omnidirectional M-mode echocardiography and its standard deviation (T_m-12-sd), and the maximum difference (T_m-12-dif) were calculated. The time to peak radial systolic strain (T_(SR)) of LV in 12 segments were measured with two-dimensional strain and its standard deviation (T_(SR)-12-sd), and the maximum difference (T_(SR)-12-dif) were calculated. The T_m-12-sd, T_m-12-dif, T_(SR)-12-sd and T_(SR)-12-dif were used as systolic asynchrony indicators. The value (-x)±2s in the control group was defined as the normal upper limit which represents 97.7% of the control group distribution. Any values above this limit in HF patients were classified as LV asynchrony. The results of two methods were analyzed with Kappa test. Results Compared with the controls, T_m-12-sd, T_m-12-dif, T_(SR)-12-sd and T_(SR)-12-dif were significantly higher in the HF group (P<0.001); there was consistency between T_m-12-sd and T_(SR)-12-sd, T_m-12-dif and T_(SR)-12-dif in detecting LV systolic asynchrony in HF group (Kappa=0.661, 0.733). Conclusion T_m-12-sd and T_m-12-dif of omnidirectional M-mode echocardiography have consistency with T_(SR)-12-sd and T_(SR)-12-dif of two-dimensional strain. These two technologies both have ability to evaluate LV radial systolic synchronicity.
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Objective To investigate the value of two-dimensional speckle tracking imaging (2D-STI) in assessing left ventricular global and regional myocardial function in normal rats. Methods Echocardiography was performed during low-dose dobutamine stress in 20 normal adult male Wistar rats. High frame rate of 2D images were recorded from the left ventricular short-axis views at the papillary muscle level. Peak systolic radial strain (PRS) and circumferential strain (PCS) of each segment, left ventricular global peak systolic radial strain (G_(PRS)) and circumferential strain (G_(PCS)) were measured at EchoPAC work station. Left ventricular internal diameter at diastole (LVIDd), systole (LVIDs), fractional shortening (FS) and ejection fraction (EF) were measured with anatomical M-model echocardiography. Dynamic changes of each index during stress experiment were observed. The correlations between EF and left ventricular global two-dimensional strain (G_(PRS), G_(PCS)) were analyzed respectively. Results PRS was similar in all segments of mid-ventricular in short-axis view (P>0.05) at baseline, while PCS of each segment showed heterogeneity, with the anteroseptal and anterior wall showing the largest value and the inferior wall showing the lowest value (P0.05). Conclusion With good reproducibility, 2D-STI can noninvasively and easily assess global and regional left ventricular myocardial deformation of normal rats at rest and during low-dose dobutamine stress.
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city on the systolic function of left ventricular subendocardial myocardium, and early monitor the epirubicin-induced cardiotoxic-ity.
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Objective To explore the value of two-dimensional strain echocardiography for quantitative assessing the change of regional left ventricular myocardial function in rats following acute myocardial infarction. Methods Sixty Wistar rats were randomly divided into two groups. The study group consisted of 50 rats with occlusion of LAD for 30-45 minutes and the sham-operated group consisted of 10 rats without occlusion of LAD. Echocardiography were performed before operation, which was defined as baseline, and 1 week, 4 weeks and 8 weeks after operation. Left ventricular internal diameter at diastole ( LVIDd) and systole < LVIDs), fractional shortening( FS), ejection fraction (EF) and left ventricular mass(LVM) were measured by anatomical M-model echocardiography. High frame rate two-dimensional images were recorded in the left ventricular short-axis views at the papillary muscle level. Peak systolic radial strain(PRS) and circumferential strain(PCS) of each segment were measured using 2-dimensional strain software. The rats were sacrificed and the infarcted size of each segment was measured using triphenyl tetrazolium chloride (TTC) after echocardiography was performed. Fibrosis of left ventricular myocardium was displayed using Van Gieson stain in 1 weeks after infarction. Results Based on the TTC findings,the left ventricle of the study group was divided into three regions:infarcted,peri-infarct and remote myocardial regions. Van Gieson stain showed fibrosis existed in all the three regions. Compared with baseline and sham-operated group, PRS and PCS of infarcted, peri-infarct and remote myocardial regions of the study group significantly decreased within 1 week after operation ( P <0. 01) and persisted for 8 weeks. PCS and PRS of infarcted, peri-infarct and remote myocardial regions of the study group in 4 weeks and 8 weeks after operation showed no significant difference when compared with those in 1 week after operation ( P >0. 01). Compared with baseline and sham-operated group,LVIDd,LVIDs and LVM of study group all increased significantly ( P <0. 05) in 4 weeks and 8 weeks after operation,and FS and EF reduced significantly ( P <0. 05). Two-dimensional strain obtained in interobserver and intraobserver both showed high agreement. Conclusions Two-dimensional strain echocardiography can assess regional function of myocardium with different perfusion in rats following acute myocardial infarction, and provides a sensitive and reliable method to follow up the process of left ventricular remodeling after myocardial infarction.