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Objective:To study the prognostic value of left atrial strain in diastolic function response by treadmill exercise stress echocardiography.Methods:During May 2018 to February 2019, 64 patients underwent treadmill exercise stress echocardiography for diastolic function evaluation in Tangdu Hospital, Air Force Medical University, were recruited.Patients were categorized into diastolic stress test negative group (pre-stress E/e′ <14 & post-stress E/e′<14) (DST- group), and diastolic stress test positive group (pre-stress E/e′ <14 & post-stress E/e′>14) (DST+ group). Patients′ characteristics of the stress test, left ventricular diameter, left atrial volume index, systolic and diastolic function, and left atrial strain parameters were compared between these two groups. ROC analyses were performed based on the echocardiographic parameters with significant group differences ( P<0.01) to determine the predictive values for diastolic stress test response. Results:The pre-stress E/e′ and left atrial strain parameters were significantly differently between DST- and DST+ group. The DST- showed significantly lower E/e′ (8.20±1.27 vs 10.32±1.33, P<0.01), but higher left atrial strains than DST+ group[reservoir function(33.7±5.7)% vs (26.5±5.5)%, P<0.01; conduit function(16.8±4.0)% vs (11.8±3.4)%, P<0.01; pump function(16.9±5.7)% vs (14.7±5.5)%, P<0.05]. The left atrial reservoir function, conduit function and pre-stress E/e′ could predict the diastolic stress test response, the areas under ROC curve were 0.81 ( P<0.01), 0.62 ( P=0.04) and 0.71 ( P<0.01). Conclusions:The left atrial strain parameters under resting condition could predict the diastolic stress test response. It may serve as an alternative method of exercise stress echocardiography for diastolic function evaluation.
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Objective: To evaluate changes of myocardial ischemia reperfusion injury (MIRI) after percutaneous coronary intervention (PCI) using regular echocardiography and 2D-STE. Methods: Thirty-two myocardial infarction patients who would underwent emergency PCI were included, among them 15 demonstrated clinical MIRI after PCI, while the other 17 not. Regular and two-dimensional speckle tracking echocardiography (2D-STE) were performed before (within 8 h) and after (within 2 h) PCI for evaluation on left ventricular structure, diastolic and systolic function and global longitudinal strain (GLS). All the echocardiographic parameters were compared between and within groups. Results: There was no significant difference of left heart diameter nor wall thickness between 2 groups before and after PCI (all P>0.05). Patients without MIRI showed no significant change of diastolic function, while those with MIRI showed reduced diastolic function demonstrated by decreased mitral flow velocity and annular velocity in early-diastole (E and e), and increased E/e (P<0.05). The eject fraction (EF) and GLS were significantly improved after PCI in patients without MIRI, whereas no change of EF but reduced GLS was observed in patients with MIRI. Conclusion: Patients with clinical MIRI after PCI suffered from reduced diastolic function and GLS. Regular echocardiography and 2D-STE should be combined to examine patients with MIRI after PCI.
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Objective To decompose left ventricular contractile motions and analyze the corresponding contributions of different components to left ventricular systolic function . Methods Sixty‐nine healthy adults with normal left ventricular eject fraction ( LVEF ) were recruited . T wo‐dimensional speckle tracking echocardiography was performed by GE Vivid E 9 system ,and strain parameters were analyzed by EchoPac software . Correlation and multiple stepwise regression analysis were performed to analyze the contributions of different components of myocardial motion to left ventricular contraction . Results Global longitudinal strain ( GLS) ,global circumferential strain ( GCS ) ,global radial strain ( GRS ) and twist were all significantly correlated with LVEF ( r ＝ －0 .668 , P ＜0 .001 ; r ＝ －0 .552 , P ＜0 .001 ;r ＝0 .335 , P ＝0 .006 ; r ＝0 .428 , P ＜0 .001) . Significant correlations were found between all the strain parameters ,except for GRS and twist . M ultiple stepwise regression adjusted for sex ,and age showed that the uni‐contributions of GLS , GCS , GRS and twist to LVEF were 21 .3% , 13 .0% , 7 .5% , 8 .8% , respectively . However ,with all strain parameters in the general regression model ,only GLS and twist were still significantly related with LVEF ( R2 ＝0 .566 , P ＜0 .001) . Conclusions T he contributions of various components of myocardial motion to left ventricular contraction in healthy adults are different . Although every component is significantly related with LVEF ,the longitudinal and twist motion are most important in the integrated view .
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Objective To analyze the dose dependent cardiotoxicity of cyclophosphamide and thus establish the mouse models for understanding the underlying mechanisms . Methods Thirty mice ( 7 -8 weeks old) were randomly divided into 6 groups:control of one course group ,control of two courses group , one course of low dose ( 50 mg/kg) group ,two courses of low dose group ,one course of high dose ( 100 mg/kg) group ,two courses of high dose group . The changes of cardiac function and morphology were analyzed at indicated times by ultrasound and histology respectively . Results Compared with the control groups , injection of low dose cyclophosphamide either with one course or two courses ,and injection of high dose with only one course had no in statically significant changes in hair color ,physical activity ,body weight and cardiac function( P > 0 .05) . Treatment of two courses with high dose resulted in significant decrease of physical activity and body weight ( P < 0 .05 ) . Meanwhile ,cardiac systolic function was significantly decreased( P <0 .05) . Histology study revealed robust cardiac hypertrophy and fibrosis . Conclusions Two courses of intraperitoneal injection of cyclophosphamide at high dose result in obvious cardiotoxicity , especially systolic dysfunction .Intraperitoneal injection of two courses of cyclophosphamide serves as a good strategy to induce cardiotoxicity in mice ,which could be applied for future mechanism study .
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Objective To propose an accurate method of noninvasive determination of central venous pressure(CVP ) by locating the central point of right atrium (RA ) using echocardiography .Methods Through the 3D reconstruction ,the accurate positions of RA of 30 patients who had been examined by multislice 3‐dimensional computed tomography for chest imaging were recorded .Based on solid geometric principles ,the central point in RA was located by echocardiography and then compared with CT‐location point .The accuracy and feasibility were assessed by absolute distance (Da) ,vertical distance (Dv) and the whole time of location (T) between the two points .Results Mean Da ,Dv and T of the whole subjects were 07.6cm(95% CI:06.2to08.1cm),01.6cm(95% CI:-00.2to03.4cm),and438.0s(95% CI:400.1to 47 4.0 s) ,respectively .Conclusions The echocardiographic method on the basis of solid geometry proposed in this study could be used to locate the central point in RA accurately and simply .Thus it would be helpful to improve the accuracy of noninvasive determination of central venous pressure .
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Objective To determine the central venous pressure (CVP) noninvasively based on hemodynamics principles using ultrasound location of the collapse point of the internal jugular vein.Methods Forty patients were enrolled in this study.The collapse point of the internal jugular vein was located and marked by a linear transducer,the body mark of right atrium was marked on the right lateral wall of the chest.The noninvasive CVP was calculated according to the vertical distance between those two points.The invasive CVP determination by central venous catheter was also carried out on all the patients.Correlation analysis was used to compare the invasive and noninvasive methods.With invasive determination of CVP as the gold standard,the ROC curve of the noninvasive ultrasound method was sketched to explore the optimal cut-off points.Results The correlation analysis reveal high positive correlation between CVPs determined by ultrasound imaging and central venous catheter (r =0.906,P ＜0.01).By the ROC curve test,fluid column height of 10.75 cm by ultrasound method was determined as the cut-off point,with the sensitivity and specificity of diagnosing elevation of CVP being 88.9％ and 93.5 ％ respectively.The corresponding area under the curve was 0.971.Conclusions Ultrasound imaging could be used to determine CVP noninvasively,which would be helpful in diagnosis of the circulating load of patients.
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ObjectiveTo explore the characteristics of the fetal pulmonary venous Doppler spectrum in medium-term and terminal pregnancy and to evaluate its application in the cardiac function assessment and lung maturation.Methods The study group consisted of 86 normal fetuses aged from 23rd to 41st week's gestation.The Doppler echocardiography was used to record the pulmonary venous spectra.The peak diastolic velocity (D),deceleration time of D wave,deceleration of D wave (Ddec),the peak systolic velocity (S),acceleration time of S wave,and acceleration of S wave of the right superior pulmonary vein (Sac.c) were measured.Sacc/Ddec was calculated.The Tei index of the left ventricle was calculated.ResultsThe D and deceleration time of D wave and Ddec increased with gestational age (P ＜ 0.05).S,the acceleration time of S wave and Sacc showed no significant correlation with gestational age.Sacc/Ddec ratio was more likely smaller than 1 with the gestational age less than 28 weeks and larger than 1 with the gestational age longer than 28 weeks ( P ＜0.05).ConclusionsD wave flow velocity,deceleration time of D wave and the Ddec of the right superior pulmonary vein had a good correlation with the global left ventricular function.The Sac/Ddec ratio might be new index for assessing cardiac function and lung maturation.
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ObjectiveTo test the reproducibility of wave intensity (WI)analysis derived measurements of pulse wave velocity (PWV),and to compare it with the traditional method-applanation tonometry.MethodsOne hundred and ten outpatient volunteers were enrolled in the study.The R-W1 of right brachial artery and right posterior tibial artery were measured through WI in diagnostic ultrasound equipment (Aloka α10),and were used to calculate the right brachial artery PWV which were also measured by tonometry (VP-1000) simutaneously;thus 30 of these volunteers were randomly selected to repeat the above examinations in the same session.Differences between the two methods were investigated by means of a paired t-test,and their linear correlations were also analyzed.Bland-Altman method was used to analyze the agreement between the two methods and their intraobserver intrasession variabilities.ResultsMean baPWVs determined by WI and tonometry were (13.03 ± 1.93) m/s and ( 12.05 ± 2.02) m/s,respectively (P ＜0.001),and the mean of their difference was (0.98 ± 1.1)m/s giving 95 ％ limits of agreement of ( - 1.18 m/s,3.14 m/s).Values of PWV obtained by the two systems were highly correlated( r =0.85,P＜ 0.001 ),with their intraobserver intrasession variabilities being 8.2％ and 7.0％,respectively.ConclusionsWI provides a new noninvasive and convenient method to measure PWV with good agreement and similar reproducibility to the standard tonometry system.
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ObjectiveTo quantify the underestimation of cardiac blood flow velocities measured by Doppler echocardiography and to explore a method for correction using a new explored dual PW/TDI technique.MethodsThe dual PW/DTI mode was used to simultaneously record the aortic,mitral,tricuspid and pulmonary valvular blood flow velocity and the adjacent valvular annulus velocity in forty healthy volunteers,then the underestimations of the flow velocities were calculated.ResultsThe true blood flow velocity relative to the valvular annulus could be obtained by dual PW/TDI technique.Conventional Doppler echocardiographic measurements significantly underestimated the true velocity ( P ＜ 0.001).The actual aortic blood flow velocity had a significant underestimation of (8.5 ± 1.2) ％,the actual flow velocity of the pulmonary artery had a significant underestimation of (6.6 ± 1.1) ％,the underestimations of E and A wave of mitralvalve's were (13.4 ± 1.7)％ and (16.7± 3.4)％,the underestimations of E and A wave of tricuspid valve' s were ( 18.7 ± 1.9) ％ and (26.0 ± 16.1 ) ％.ConclusionsThe cardiac blood flow velocity measured by Doppler ultrasound has been significantly underestimated and this underestimation can bequantified and corrected using dual PW/DTI technique based on the principle of motion relativity.