Right ventricular volume and function by three-dimensional echocardiography: results of the echocardiographic measurements in normal Chinese adults (EMINCA) II.

Three-dimensional (3D) echocardiography is an emerging technique for assessing right ventricular (RV) volume and function, but 3D-RV normal values from a large Chinese population are still lacking. The aim of the present study was to establish normal values of 3D-RV volume and function in healthy Chinese volunteers. A total of 1117 Han Chinese volunteers from 28 laboratories in 20 provinces of China were enrolled, and 3D-RV images of 747 volunteers with optimal image quality were ultimately analyzed by a core laboratory. Both vendor-dependent and vendor-independent software platforms were used to analyze the 3D-RV images. We found that men had larger RV volumes than women did in the whole population, even after indexing to body surface area, and older individuals had smaller RV volumes. The normal RV volume was significantly smaller than that recommended by the American Society of Echocardiography/European Association of Cardiovascular Imaging guidelines in both sexes. There were significant differences in 3D-RV measurements between the two vendor ultrasound systems and the different software platforms. The echocardiographic measurements in normal Chinese adults II study revealed normal 3D-RV volume and function in a large Chinese population, and there were significant differences between the sexes, ages, races, and vendor groups. Thus, normal 3D-RV values should be stratified by sex, age, race, and vendor.

Allometric model improves scaling of left atrial size in obese population: the use of body weight containing variables is challenged.

BACKGROUND: Scaling left atrial (LA) size remains a challenge. An allometric model using body weight (BW) as scaling variable was recently proposed. We sought to examine the performance of this model in an obese population. METHODS: A total of 266 consecutive overweight (110) and obese subjects (class I, II, and III obese 81, 47, and 28, respectively) were studied; 46 normal subjects with normal body mass index (BMI) served as controls. LA dimension (LAD) was scaled to BW, body surface area (BSA), BMI and height, respectively, using both isometric and allometric models. RESULTS: There were no significant differences in age, gender, or height among the five groups. The prevalence of comorbid conditions, wall thickness, E/E' and LAD measures increased significantly with increasing weight group (P < 0.01-0.001). With the isometric model, LAD corrected by BW, BSA, and BMI significantly but paradoxically decreased across the groups (P < 0.05-0.001). With the allometric model, LAD overcorrection by BM, BSA, and BMI was improved, but remained in the class III obese group. In contrast, scaling LAD to height showed significant and graded increase across the five groups in accordance with the increases of BMI, E/E' and the prevalence of comorbid conditions. CONCLUSION: All isometric models that correct LAD by BW or BW containing variables underestimate LA size in overweight and obese groups. The allometric model using height provides more consistent results and should be preferred to models using BW or BW containing variables in scaling LAD in obese population.

Plaque volume compression ratio, a novel biomechanical index, is independently associated with ischemic cerebrovascular events.

OBJECTIVE: The purpose of this study was to develop a new biomechanical index for assessing the elastic characteristics of carotid plaques and to test the association between carotid plaque elasticity and ischemic cerebrovascular events (ICEs). METHODS: One hundred and eighteen carotid plaques were detected with real-time three-dimensional ultrasonography in 104 patients. All patients received MRI and were divided into two groups according to the history of ICEs: patients with ICEs (n=58, including 20 patients with transient ischemic attack and 38 with ischemic stroke) and patients without ICEs (n=46). The carotid plaque volume at end diastole (Vd) and end systole (Vs) was measured by use of a TomTec (Munich, Germany) workstation. Plaque volume compression ratio (VCR) was calculated as (Vd-Vs)/Vd x 100 and the reproducibility of VCR measurement was analyzed. The carotid intima-media thickness, plaque area and plaque acoustic density were also measured. Multivariate logistic regression was used to test the association between ICEs and plaque ultrasonic parameters or traditional risk factors including age, sex, smoking, blood pressure, history of coronary heart disease, levels of serum low-density lipoprotein, triglyceride and glucose. RESULTS: Satisfactory images of carotid plaques were obtained in all patients by real-time three-dimensional ultrasonography. Patients with ICEs and patients without ICEs differed significantly in VCR (22.19+/-8.42 vs. 13.95+/-7.86, P<0.01). Regression analysis revealed that systolic blood pressure, [odds ratio (OR)=1.054, 95% confidence interval (CI)=1.028-1.081, P<0.001] and VCR (OR=1.074, 95% CI=1.022-1.128, P<0.001) were associated with ICEs independently. Plaque volume had only a marginal association with ICEs (OR=1.007, 95% CI=1.000-1.013, P=0.05). CONCLUSION: Measurement of VCR provides a noninvasive approach to the evaluation of the elasticity of carotid plaques, which is associated independently with ICEs. Thus, real-time three-dimensional ultrasonography-derived VCR holds a great potential in identifying patients with high risk of ICEs.

[The correlation of human serum Lp-PLA2 and hs-CRP and stability of coronary atherosclerotic plaques].

OBJECTIVE: To explore the relationship of serum lipoprotein-associated phospholipase A2 and high sensitive C-reactive protein in vulnerable coronary atherosclerotic plaques. METHODS: Patients undergoing coronary angiography (CAG) were examined for CAD with intravascular ultrasound (IVUS). According to the findings of CAG and IVUS, all the patients were divided into three groups: a control group without plaque, stable plaque group and vulnerable plaque group. The total serum Lp-PLA2 and hs-CRP were measured before angiography and they were valued with T test and Pearson's correlation analysis. RESULTS: (1) Lp-PLA2 level in stable plaque group and vulnerable plaque group was higher than that in control group (P < 0.05). (2) Lp-PLA2 level in the vulnerable plaque group was higher than that in stable plaque group (P < 0.05). (3) hs-CRP level in the vulnerable plaque group is higher than that in the stable plaque group and control group (P < 0.05) and there was significant difference between them. (4) To discriminate vulnerable plaque, the specificity of serum Lp-PLA2 was stronger than that of hs-CRP. CONCLUSIONS: Serum Lp-PLA2 level has higher sensitivity in predicting the vulnerability of the coronary atherosclerotic plaque than hs-CRP. In combination with hs-CRP, we can use Lp-PLA2 as a new biomarker to predict the presence of vulnerable plaque.

A Novel Mathematical Model for Correcting the Physiologic Variance of Two-Dimensional Echocardiographic Measurements in Healthy Chinese Adults.

BACKGROUND: To facilitate differentiation between normal and abnormal values, it is necessary to correct echocardiographic measurements for physiologic variance induced by age, gender, and body size variables. METHODS: A total of 34 two-dimensional echocardiographic parameters were measured in 1,224 healthy Chinese adults with body mass index < 25.0 kg/m2. An optimized multivariate allometric model and scaling equations were first developed in 858 subjects (group A), and their reliability was then verified in the remaining 366 subjects (group B). The traditional single-variable isometric model in which parameters are linearly corrected by a single body size variable (height, weight, body mass index, or body surface area) was used for comparison. The success of correction was defined as the absence of significant correlations (r > 0.20, P < .05) between the corrected values and age or any body size variables, while maintaining high correlations (r > 0.80) between the corrected and uncorrected values. RESULTS: Before correction, all 34 parameters correlated significantly with one or more of the physiologic variables of age and body size and differed significantly between men and women on 29 parameters (85.3%) in both groups. The success rate of correction with the single-variable isometric model was only 11.0% (15 of 136 corrections due to four variable corrections used for each parameter), while use of the optimized multivariate allometric model successfully corrected all 34 parameters (100%) for physiologic variance induced by age and body size variables and eliminated the gender differences in 32 parameters (94.1%). A new set of reference values for corrected echocardiographic measurements independent of age, gender, and body size variables were established. CONCLUSIONS: The novel optimized multivariate allometric model developed in this study is superior to traditional the single-variable isometric model in the correction of echocardiographic parameters for physiologic effects of age, gender, and body size variables and thus should be encouraged in both scientific research and clinical practice.

Impact of the number of image planes of real-time three-dimensional echocardiography on the accuracy of left atrial and ventricular volume measurements.

Real-time three-dimensional (3D) echocardiography (RT-3DE) has emerged as a new technique in measuring left atrial and ventricular volume. However, the impact of cutting planes of RT-3DE on the accuracy of volume measurement in patients with a normal or enlarged heart is still unknown. We enrolled 30 normal subjects (control group) and 30 patients with heart failure (patient group). RT-3DE was performed to measure maximal volume of the left atrium (LAVmax) and left ventricular end-diastole volume (LVEDV) with 2-, 4-, 8- and 16-cutting planes, compared with cardiac magnetic resonance imaging (CMRI). In both groups, LAVmax by RT-3DE using 2- and 4-cutting planes was significantly underestimated (mean difference: -10.4 +/- 16.6 mL, p = 0.001 and -8.8 +/- 14.2 mL, p = 0.002 in the control group and -13.4 +/- 19.6 mL, p = 0.001 and -11.2 +/- 17.5 mL, p = 0.001 in the patient group, respectively). These differences became nonsignificant when 8- and 16-cutting planes were adopted (mean difference: -2.1 +/- 7.6 mL and -1.9 +/- 7.4 mL in the control group and -2.7 +/- 8.4 mL and -2.2 +/- 8.3 mL in the patient group, respectively). The agreement for LVEDV was acceptable when 4- or more cutting planes were used in the control group and when 8- or 16-cutting planes were used in the patient group. The time expense for data analysis of LAVmax with 8-image planes was only 7 +/- 4 min in the control group and 6 +/- 5 min in the patient group, almost halving that of the 16-image planes. Similarly, 4- and 8-cutting planes were required for an accurate measurement of LVEDV in the control and patient groups, respectively. In conclusion, RT-3DE with 8-cutting planes is both accurate and timesaving for measurement of LAVmax and LVEDV in patients with normal or enlarged left atria and ventricles.

Quantification of regional volume and systolic function of the left ventricle by real-time three-dimensional echocardiography.

Real-time three-dimensional (3D) echocardiography (RT-3DE) provides a unique technique to evaluate left ventricular regional function in a 3D format. We aimed to explore whether the left ventricular segmental volume and systolic function is uniform and to establish normal values of volume and systolic function parameters of 16 regions in healthy subjects. RT-3DE was performed in 41 normal subjects and four-dimensional (4D)-left ventricle (LV) analysis software and a TomTec workstation were used to analyze data for regional end-diastolic volume (EDV(R)), regional end-systolic volume (ESV(R)), regional stroke volume (SV(R)), regional ejection fraction (EF(R)), ratio of SV(R) to global SV (SV(R/G)) and ratio of SV(R) to global EDV (EF(R/G)). All regional volume and systolic function parameters were not uniform among the left ventricular walls. They all increased in the order of inferior, posterior, lateral, septal, anterior and antero-septal walls with an increasing trend from the apical, middle to basal segments. The systolic function (EF(R), SV(R/G) and EF(R/G)) of the anterior and antero-septal walls was significantly higher than that of the lateral, inferior and posterior walls. And the intra- and interobserver variability for EDV(R), ESV(R), SV(R/G) and EF(R/G) ranged from 2.9% to 5.8%. In conclusion, the regional volume and systolic function of the left ventricle is not uniform and, therefore, a normal left ventricle cannot be regarded as a symmetric model for assessing the regional systolic function. This information may improve the accuracy of RT-3DE techniques in the assessment of the left ventricular regional function. (E-mail: zhangyun@sdu.edu.cn and yaogh@yahoo.com).

Quantification of transmural gradient of blood flow in myocardial ischemia with real-time myocardial contrast echocardiography and dipyridamole stress test.

Transmural redistribution of myocardial blood flow (MBF) is the earliest sign of myocardial ischemia. We aimed to evaluate the ability of real-time myocardial contrast echocardiography (MCE) combined with dipyridamole stress to quantify the transmural gradient of MBF during graded coronary stenosis. Real-time MCE was performed in 14 open-chest dogs at seven experimental stages: baseline; hyperemia induced by 6-min infusion of dipyridamole; 50%, 75% and 90% reduction of hyperemic flow after constriction in each stage for 10 min; reperfusion for 10 min; and subtotal occlusion of the left anterior descending coronary artery (LAD) for 90 min. We obtained MCE perfusion parameters from subendocardial (A-endo, beta-endo and A x beta-endo) and subepicardial (A-epi, beta-epi and A x beta-epi) layers of the ventricular septum and calculated their transmural gradients (A-EER, beta-EER and A x beta-EER) and systolic wall thickening (SWT). The sensitivity and specificity of each parameter for predicting 75% reduction of hyperemic flow, which was defined as mild myocardial ischemia, were derived by receiver operating characteristic (ROC) curve analysis. No transmural gradients were found at baseline; during maximal hyperemia and 50% reduction of hyperemic flow. beta-endo, A x beta-endo, beta-EER and A x beta-EER decreased significantly when the hyperemic flow was reduced by 75% or more. In contrast, SWT remained unchanged until the hyperemic flow was reduced by 90%. Among all parameters measured, beta-EER and A x beta-EER had the highest and SWT the lowest sensitivity and specificity in predicting mild myocardial ischemia. In conclusion, real-time MCE combined with dipyridamole stress allows for quantification of the transmural gradient of MBF. beta-EER and A x beta-EER are more sensitive than SWT and other MCE parameters in detecting mild myocardial ischemia.

How many planes are required to get an accurate and timesaving measurement of left ventricular volume and function by real-time three-dimensional echocardiography in acute myocardial infarction?

To derive the optimal cutting planes of real-time 3-D echocardiography (RT-3DE) for measuring left ventricular volume and ejection fraction (EF) in the presence of left ventricular regional wall motion abnormalities, 14 open-chest dogs were studied with RT-3DE full volume imaging and 2-D echocardiography (2DE) after left anterior descending coronary arteries were occluded for 90 min. Left ventricular end diastolic volume (EDV), end systolic volume (ESV), stroke volume (SV) and EF were measured off-line with 2DE and RT-3DE (2-, 4- and 8-plane) methods. The autopsy EDV was estimated by the volume of saline solution injected into the excised heart and served as the reference volume (RefV) for comparison with EDV measured by 2DE and RT-3DE. Agreement analysis was performed according to the method of Bland and Altman. There were excellent correlations between 2DE, RT-3DE (2-plane) and RT-3DE (4-plane) methods on one hand, and RT-3DE (8-plane) method on the other in the measurements of EDV, ESV and SV (r = 0.84-0.99). However, 2DE and RT-3DE (2-plane) measurements significantly underestimated RT-3DE (8-plane) (p < 0.01), whereas no significant differences between RT-3DE (4-plane) and RT-3DE (8-plane) were found in terms of EDV, ESV and SV measurements. The values of EF determined by 2DE, RT-3DE (2-plane) and RT-3DE (4-plane) methods correlated highly with that by RT-3DE (8-plane) (r = 0.82-0.98) and there was no significant difference between the two measurements. EDV values determined by 2DE, RT-3DE (2-plane), RT-3DE (4-plane) and RT-3DE (8-plane) correlated highly with RefV (r = 0.84, r = 0.92, r = 0.94 and r = 0.97, respectively) and there was no significant difference between RefV and EDV by RT-3DE (4-plane) and RT-3DE (8-plane). In contrast, EDV measured by 2DE and RT-3DE (2-plane) methods underestimated RefV significantly (p < 0.01). In conclusion, RT-3DE allows reliable and reproducible measurement of left ventricular volume and EF, even in the presence of left ventricular regional wall motion abnormalities. RT-3DE (4-plane) is the method of choice for an accurate and timesaving quantification of left ventricular volume and function.

Doppler Echocardiographic Measurements in Normal Chinese Adults (EMINCA): a prospective, nationwide, and multicentre study.

AIMS: Currently, available Doppler echocardiographic reference values are derived mainly from North American and European population studies, which may not applicable to the Chinese population. We aimed to establish normal reference values of Doppler echocardiographic parameters in a nationwide, population-based cohort of healthy Han Chinese adults. METHODS AND RESULTS: A total of 1394 qualified healthy subjects (mean age 47.3 ± 16.0 years, 678 men) were enrolled at 43 collaborating laboratories, 37 transvalvular flow and tissue Doppler parameters were obtained, and the impacts of gender and age on each parameter were analysed. Significant differences were found between men and women in 48.6% (18/37) of the parameters analysed, and among different age groups in 83.8% (31/37) of the parameters in men and in 86.5% (32/37) of the parameters in women. CONCLUSIONS: Normal reference values of Doppler echocardiographic parameters were established for the first time in a nationwide, population-based cohort of healthy Han Chinese adults. Since most of these parameters differed by gender and/or age, reference values specified for gender and age should be recommended in clinical practice.

[Effects of Different Kinds of Organic Materials on Soil Heavy Metal Phytoremediation Efficiency by Sedum alfredii Hance].

In this study, a pot experiment was conducted to investigate the effect of clean organic materials i. e., biogas residue (BR), mushroom residue (MR), and bamboo shell (BS) on phytoextraction remediation of two heavy metal contaminated soils (collected from Wenzhou and Fuyang, which referred to "Wenzhou soil" and "Fuyang soil", respectively.) using a cadmium (Cd) and zinc (Zn) hyperaccumulator Sedum alfredii Hance. The results indicated that the effects of organic materials on availabilities of soil heavy metals were different due to different kinds of heavy metals, organic materials, and the application rates of the organic materials. Addition with 5% BR showed the greatest activation to copper (Cu), Zn in Wenzhou soil, and in Fuyang soil 1% BS had the highest activation for Cu, Zn, lead ( Ph) and Cd. Growth of shoot biomass of Sedum alfredii Hance increased with the addition rate of organic materials, and the plant dry weights were increased by 23.7%-93.0%. In Wenzhou soil, only 1% BS treatment had the best effect on Cd uptake and accumulation in shoots of Sedum alfredii Hance, increased by 22.6%, while other treatments were inferior to the control. For Zn, MR treatments were inferior to the control, while other treafments were superior to the control, of which 5% BR, 1% BS and 5% BS exceeded the control by 39. 6%, 32.6% and 23.8%, respectively. In Fuyang soil, for Cd, the treatment effects of 5% BS, 1% BR and 5% BR were the greatest, of which Cd accumulation in shoots exceeded the control by 12.9%, 12.8% and 6.2%, respectively, while Cd accumulations in shoots in all other treatments were less than that of control. For Zn, the treatments of adding organic materials promoted Zn accumulation in shoots of Sedum alfredii Hance, and the best treatments were as follows: 5% BS. 5% BR and 5% MR, exceeded the control by 38.4%, 25.7% and 22.4%, respectively.

Echocardiographic measurements in normal chinese adults focusing on cardiac chambers and great arteries: a prospective, nationwide, and multicenter study.

BACKGROUND: Currently available echocardiographic reference values are derived mainly from North American and European population studies, and no echocardiographic reference values are available for the Chinese population. The aim of this study was to establish normal values of echocardiographic measurements of the cardiac chambers and great arteries in a nationwide, population-based cohort of healthy Han Chinese adults. METHODS: A total of 1,586 healthy Han Chinese volunteers aged 18 to 79 years were screened at 43 collaborating laboratories throughout China. Standard M-mode and two-dimensional echocardiography was performed to obtain measurements of the cardiac chambers and great arteries. The impacts of gender and age on all echocardiographic measurements were analyzed. RESULTS: A total of 1,394 qualified healthy subjects (mean age, 47.3 ± 16.0 years; 678 men) were ultimately enrolled. Except for left ventricular ejection fraction, values of cardiac chamber and great arterial dimensions were significantly higher in men than in women. Most measurements of the atrial and great arterial dimensions, left ventricular wall thickness, and left ventricular mass increased with age in both men and women. CONCLUSIONS: Normal reference values of cardiac dimensional parameters were established for the first time in a nationwide, population-based cohort of healthy Han Chinese adults. Because most of these parameters were found to vary with gender and age, reference values stratified for gender and age should be used in clinical practice.

[Induction of atherosclerotic plaque instability in rabbits after transfection of human wild-type p53 gene].

OBJECTIVE: To develop an animal model of unstable atherosclerotic plaques. METHODS: Sixty-four New Zealand white rabbits were randomly divided into two groups: group A (n = 54, undergoing balloon-induced abdominal aortic wall injury and then fed on a diet of 1% cholesterol) and group B (n = 10, fed on a diet of 1% cholesterol only). At the end of the eighth week, the rabbits in group A were randomly divided into two subgroups: group A1 (n = 27) and group A2 (n = 27). Recombinant adenovirus carrying human wild-type p53 gene and beta galactosidase (LacZ) genes were injected through a catheter into the aortic segments rich in plaques in group A1 and A2 respectively. Two weeks later, 10 rabbits each in group A1 and A2 were killed to observe the occurrence rate of spontaneous plaque rupture, and the remaining rabbits in group A1, A2 and B all underwent pharmacological triggering by Chinese Russell's viper venom injected subperitoneally and histamine injected intravenously two times with an interval of 24 hours. Twenty-four hours after the second pharmacological triggering the remaining rabbits were all killed and their abdominal aortae were taken out to undergo macropathologic observation, staining, and immunohistochemistry to examine the accumulation of macrophages and the expression of p53 protein, in the plaques with and without rupture respectively. At the beginning of the experiment and before being killed the serum total cholesterol (TC), triglyceride (TG), low-density lipoprotein choloesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) were examined. RESULTS: Before the rabbits were killed the blood-lipid levels were significantly increased in comparison with the baseline levels (all P < 0.01), however, without significant differences among the three groups. The rate of cells positive in p53 transfection was 32.4% +/- 10.2% in the group A1, significantly higher than those in the group A2 and group B (15.8% +/- 3.6% and 16.2% +/- 6.7% respectively, both P < 0.001). The fibrous cap of the plaque was significantly thinner in the group A1 than in the other 2 groups (both P < 0.05). The apoptosis rate was 2.5% +/- 0.8% in the group A1, significantly higher than those in the group A2 and group B (1.0% +/- 0.3% and 0.9% +/- 0.4% respective, both P < 0.01). The accumulation of macrophages within the plaques was significantly remarkable and the number of vessel smooth muscle cells was much smaller in the group A1. Plaque rupture and thrombosis occurred in 12 rabbits, numbering 20 lesions, after pharmacological triggering in the group A1, and occurred in only 5 rabbits, numbering 7 lesions, in the group A2. None of the rabbits in group B showed any lesions after the pharmacological triggering. CONCLUSION: With transfection of human wild-type p53 genes and pharmacological triggering, plaque rupture and thrombosis may occur in most atherosclerotic lesions in rabbits, which offered a reliable model for the further study of unstable plaques.

Doxycycline stabilizes vulnerable plaque via inhibiting matrix metalloproteinases and attenuating inflammation in rabbits.

Enhanced matrix metalloproteinases (MMPs) activity is implicated in the process of atherosclerotic plaque instability. We hypothesized that doxycycline, a broad MMPs inhibitor, was as effective as simvastatin in reducing the incidence of plaque disruption. Thirty rabbits underwent aortic balloon injury and were fed a high-fat diet for 20 weeks. At the end of week 8, the rabbits were divided into three groups for 12-week treatment: a doxycycline-treated group that received oral doxycycline at a dose of 10 mg/kg/d, a simvastatin-treated group that received oral simvastatin at a dose of 5 mg/kg/d, and a control group that received no treatment. At the end of week 20, pharmacological triggering was performed to induce plaque rupture. Biochemical, ultrasonographic, pathologic, immunohistochemical and mRNA expression studies were performed. The results showed that oral administration of doxycycline resulted in a significant increase in the thickness of the fibrous cap of the aortic plaque whereas there was a substantial reduction of MMPs expression, local and systemic inflammation, and aortic plaque vulnerability. The incidence of plaque rupture with either treatment (0% for both) was significantly lower than that for controls (56.0%, P<0.05). There was no significant difference between doxycycline-treated group and simvastatin-treated group in any serological, ultrasonographic, pathologic, immunohistochemical and mRNA expression measurement except for the serum lipid levels that were higher with doxycycline than with simvastatin treatment. In conclusion, doxycycline at a common antimicrobial dose stabilizes atherosclerotic lesions via inhibiting matrix metalloproteinases and attenuating inflammation in a rabbit model of vulnerable plaque. These effects were similar to a large dose of simvastatin and independent of serum lipid levels.

Region of interest tracking in real-time myocardial contrast echocardiography.

The real-time myocardial contrast echocardiography (RT MCE) is a new echocardiography technology, which allows clinicians to noninvasively evaluate the perfusion of myocardial capillary of patients, using the quantitative analysis of RT MCE. But the accurate analysis requires tracking the position of region of interest (ROI) within the myocardial area, so as to compensate for the translation or rotation offsets, which are due to such uncontrollable factors as heart motion. We used diamond search method and Brox's coarse-to-fine warping optical flow technique for this ROI tracking problem. We validated our methods by comparing the quantitative analysis results of RT MCE using our methods with those using Lucas & Kanade's optical flow technique, which had been report to be accurate enough for this ROI tracking. We finally present some examples of animal experiment to show the effectiveness and the clinical application value of our ROI tracking methods.

Numerical methods and workstation for the quantitative analysis of real-time myocardial contrast echocardiography.

Using the quantitative analysis of real-time myocardial contrast echocardiography (RT MCE), clinicians can assess the myocardial perfusion of patients, noninvasively and accurately. We designed a workstation to assist clinicians to automatically implement the accurate analysis of RT MCE. The workstation can compute some hemodynamic parameters of myocardial microcirculation, e.g., myocardial blood flow, myocardial blood flow mean velocity, and myocardial blood volume. Our new methods involved in the quantitative analysis of RT MCE are summarized as follows. 1) A novel orthogonal array optimization (OAO) technique was proposed and used to estimate the unknown parameters of the nonlinear model to guarantee numerical stability. 2) Brox's coarse-to-fine warping optical flow technique was employed to automatically track the region of interest located inside the myocardial area to ensure the accuracy of the quantitative analysis. Finally, we illustrate some examples of clinical studies to indicate the effectiveness of the system and the reliability of the methods.

Gax gene transfer inhibits vascular remodeling induced by adventitial inflammation in rabbits.

AIMS: Adventitial fibroblasts (AFs) and inflammation play an important role in neointimal formation and vascular remodeling. The present study was aimed to investigate the therapeutic effects and underlying mechanisms of transcriptional regulator Gax gene transfection in aortic remodeling induced by adventitial inflammation. METHODS AND RESULTS: Fifty rabbits fed a chow diet were randomly divided into a normal control group (n=10) and experimental group (n=40). All rabbits in the experimental group underwent collar placement around the abdominal aorta and intra-collar injection of lipopolysaccharide (LPS) to induce adventitial inflammation and they were further divided into model control group, saline-treated group, green fluorescence protein (Ad-GFP)-treated group and Gax gene (Ad-Gax)-treated group, respectively. Four weeks after treatment, the model control group, saline-treated group and Ad-GFP-treated group showed thickened neointima and adventitia, reduced lumen size and increased eccentricity and remodeling index of the abdominal aorta in comparison with the normal control group, whereas Ad-Gax-treated group exhibited attenuated neointimal formation and vascular remodeling (P<0.01-0.05) .The vascular expression levels of interleukin (IL)-1ß, IL-6, IL-8, monocyte chemoattractant protein (MCP)-1, matrix metalloproteinase (MMP)-1, MMP-2, MMP-9, vascular cell adhesion molecule (VCAM)-1 and intercellular adhesion molecule (ICAM)-1, Smads, mitogen-activated protein kinases (MAPKs), integrins and nuclear factor kappa B (NF-kB) were significantly higher in the model control group, saline-treated group and Ad-GFP-treated group than those in the normal control group (P<0.01-0.05). In contrast, the local expression levels of these cytokines were substantially reduced by Ad-Gax gene transfer (P<0.01-0.05). Similarly, the serum levels of inflammatory cytokines including C-reactive protein (CRP), transforming growth factor (TGF)-ß1, IL-1, IL-6, IL-8, tumor necrosis factor (TNF)-α, MCP-1, VCAM-1 and ICAM-1 were significantly higher in the model control group, saline-treated group and Ad-GFP-treated group than those of the Ad-Gax-treated group (P<0.01-0.05). In vitro studies showed that Gax overexpression diminished inflammatory cytokine expression in LPS-stimulated arterial fibroblasts. CONCLUSIONS: Adventitial inflammation induces vascular remodeling via the interactions of multiple inflammatory cytokines and local Gax gene transfer in vivo can significantly inhibit these interactions and thereby attenuate local inflammation and vascular remodeling.

Value of left ventricular regional ejection fraction determined by real-time three-dimensional echocardiography in diagnosis of aneurysm: compared with left ventriculography.

BACKGROUND: Regional ejection fraction (EF(R)) measured by real-time three-dimensional echocardiography (RT-3DE) provides a novel method for quantifying left-ventricular (LV) regional systolic function. We aimed to explore the diagnostic value of regional ejection fraction (EFR) derived from RT-3DE in detecting LV aneurysms in patients with myocardial infarction. METHODS: Thirty-eight patients with myocardial infarction were prospectively enrolled and underwent electrocardiography (ECG), two-dimensional echocardiography (2-DE), RT-3DE and left ventriculography (LVG). Subjects with a negative EFR in at least one segment on RT-3DE were considered as having a ventricular aneurysm. We compared the sensitivity, specificity, Youden's index, and positive and negative predictive values of ECG, 2-DE and RT-3DE in determining LV aneurysm with detection by LVG. RESULTS: On LVG an LV aneurysm was diagnosed in 16 (42.1%) patients. The sensitivity and specificity were 62.5% and 86.4% for ECG, 81.2% and 95.4% for 2-DE, and 100.0% and 90.9% for RT-3DE in diagnosing LV aneurysm. Youden's indexes for ECG, 2-DE and RT-3DE were 0.49, 0.77 and 0.91, respectively. Positive and negative predictive values were 76.9% and 76.0% for ECG, 92.9% and 87.5% for 2-DE, and 88.9% and 100.0% for RT-3DE. CONCLUSIONS: RT-3DE-derived EFR provides a novel, reliable index in the diagnosis of LV aneurysm and has excellent sensitivity and specificity.