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Background: Studies have indicated that the presence and size of subclinical atherosclerotic plaques improve the prediction of atherosclerotic cardiovascular events (ASCVE) over and above that provided by conventional risk factors alone. However, the relative contribution of different ultrasonographic measurements and sites of measurements on the 10-year ASCVD risk is largely unknown.Objectives: Our aims were to determine the relative performance of carotid intima-media thickness, plaque thickness, and plaque area in 10-year ASCVD prediction when added to conventional risk factors as well as whether the vascular territory of these measurements, carotid or common femoral bifurcation, and the number of bifurcations with plaque (NBP) influence prediction.Methods: We enrolled 985 adults (mean age: 58.1 ± 10.2 years) free of atherosclerotic cardiovascular disease. Conventional risk factors were recorded, and both carotid and common femoral bifurcations were scanned with ultrasonography. The primary endpoint was a composite of first-time fatal or nonfatal ASCVE.Results: Over a mean ± SD follow-up of 13.2 ± 3.7 years, ASCVE occurred in 154 (15.6%) participants. By adding different plaque measurements to conventional risk factors in a Cox model, net reclassification improvement was 10.4% with maximum intima-media thickness, 9.5% with carotid plaque thickness, and 14.2% with carotid plaque area. It increased to 16.1%, 16.6%, and 16.6% (P < 0.0001) by adding measurements from 4 bifurcations: NBP, total plaque thickness, and total plaque area, respectively.Conclusions: NBP, total plaque thickness, or total plaque area from both the carotid and common femoral bifurcations provides a better prediction of future ASCVE than measurements from a single site. The results need to be validated in an independent cohort. [ABSTRACT FROM AUTHOR]

An editorial is presented on plaque burden and vulnerable features being at higher risk of cerebrovascular symptoms. Topics include evaluating carotid plaques using computed tomography angiography (CTA) in symptomatic patients with bilateral intraplaque hemorrhage; and computed tomography angiography being quicker and more cost-effective imaging technique than MRI and identifying vulnerable carotid plaque features.

We estimated the value of objective, computerized texture analysis of ultrasonic images in distinguishing carotid plaques associated with neurological ipsilateral symptoms (amaurosis fugax [AmF; n = 30], transient ischemic attack [TIA; n = 52], and stroke [n = 55]) from asymptomatic plaques (n = 51). We performed 3 case-control studies (1/symptom with asymptomatic plaques as control). On logistic regression, AmF was independently associated with severity of stenosis, percentage of pixels with gray levels 0 to 10 (PPCS1; measure of echolucency), and spatial gray level dependence matrices (SGLDM) information measure of correlation (IMC-1; texture); TIAs with PPCS1 (echolucency), SGLDM correlation, and skewness (both texture); and stroke with PPCS1, SGLDM correlation, and percentage of pixels with gray levels 11 to 20 (PPCS2; echolucency). The area under the curve of the regression-derived predicted probability for AmF, TIA, and stroke was 0.92, 0.82, and 0.85, respectively (all P < .001). Texture analysis can identify carotid plaques associated with a neurological event, improving the diagnostic value of echolucency measures. Texture analyses could be applied to natural history studies. [ABSTRACT FROM PUBLISHER]

Background: Unstable carotid plaques on subjective, visual, assessment using B-mode ultrasound scanning appear as echolucent and heterogeneous. Although previous studies on computer assisted plaque characterisation have standardised B-mode images for brightness, improving the objective assessment of echolucency, little progress has been made towards standardisation of texture analysis methods, which assess plaque heterogeneity. The aim of the present study was to investigate the influence of image zooming during ultrasound scanning on textural features and to test whether or not resolution standardisation decreases the variability introduced. Methods: Eighteen still B-mode images of carotid plaques were zoomed during carotid scanning (zoom factor 1.3) and both images were transferred to a PC and normalised. Using bilinear and bicubic interpolation, the original images were interpolated in a process of simulating off-line zoom using the same interpolation factor. With the aid of the colour-coded image, carotid plaques of the original, zoomed and two resampled images for each case were outlined and histogram, first order and second order statistics were subsequently calculated. Results: Most second order statistics (21/25, 84%) were significantly (p < 0.05) sensitive to image zooming during scanning, in contrast to histogram and first order statistics (4/25, 16%, p < 0.001, Fisher's exact test). Median (interquartile range) change of those features sensitive to zooming was 18.14% (4.94-28.43). Image interpolation restored these changes, the bicubic interpolation being superior compared to bilinear interpolation (p = 0.036). Conclusion: Texture analysis of ultrasonic plaques should be performed under standardised resolution settings; otherwise a resolution normalisation algorithm should be applied. [ABSTRACT FROM AUTHOR]

This article reviews the mechanisms by which micronized purified flavonoid fraction (MPFF; Dafion 500 mg) acts on symptoms as well as on edema in patients with chronic venous disease, in the light of new advances in the understanding of the pathophysiology of this chronic condition. Deterioration of venous wall tone followed by valve dysfunction leading eventually to varicose veins are the key pathophysiologic features that produce venous hypertension. Both mechanical and biological factors are responsible for the deterioration of the venous wall in large veins. These are decreased shear stress and hypoxia of the media and of the endothelium, which act as triggering factors for biochemical reactions leading to inflammation. There is a body of evidence that inflammation in chronic venous insufficiency (CVI) plays a role right from the early stages of venous dysfunction and venous valve restructuring. The whole process of venous wall stretching and dilation is painful and may present as leg heaviness, a sensation of swelling, and paresthesia. Dafion 500 mg relieves symptoms, edema, and red blood cell aggregation, which cause paresthesia and restless legs. At the level of the microcirculation, dysfunction of microvessels is observed, characterized by an increase in capillary permeability followed by skin changes. The earliest manifestation of microcirculatory disorder is edema. At this level, Daflon 500 mg acts favorably on microcirculatory complications by normalizing the synthesis of prostaglandins and free radicals. It decreases bradykinin-induced microvascular leakage and inhibits leukocyte activation, trapping, and migration. Its efficacy in decreasing CVI edema and ankle swelling has been proven in rigorous studies that are reviewed in this paper. Daflon 500 mg, a well-established oral flavonoid that consists of 90% micronized diosmin and 10% flavonoids expressed as hesperidin, may be prescribed from the very beginning of the disease for the relief of pain... [ABSTRACT FROM AUTHOR]

The current status of superficial thrombophlebitis, including incidence, diagnosis, and management, are reviewed. Treatment options are assessed in the light of data from the main studies reported in the literature. These include compression, ambulation, and nonsteroidal antiinflammatory agents and surgical management with high saphenous ligation (with or without saphenous vein stripping) with or without anticoagulants, ranging from aspirin, unfractionated heparin, warfarin, and low-molecular-weight heparin (LMWH). The advantage of the surgical approach is that by ligation with or without stripping of the superficial veins the underlying pathesis (i.e., varicose veins) is also eradicated. In the presence of deep venous thrombosis (DVT), surgery could be combined with anticoagulants. The extensive current literature for DVT treatment shows that the LMWHs are at least as effective and safe as the unfractionated heparins. On this basis, one could reasonably recommend LMWH for the treatment of superficial thrombophlebitis with involvement of the deep veins. Pentasaccharide, a drug that has been recently explored for the prophylaxis and treatment of DVT could be another option. However, there are as yet no data for recommended dosages or duration of treatment for the latter two options. [ABSTRACT FROM AUTHOR]

Compares the efficacy of endovascular sclerotherapy (ES) with surgery and surgery with sclerotherapy among patients with venous incompetence. Use of color duplex scanning to evaluate incompetence; Difference in cost between surgery alone and ES; Effectiveness of surgery and sclerotherapy for distal vein incompetence.

The authors reflect on the efficacy of statins in the treatment and prevention of venous thromboembolism (VTE). They mention several studies that were conducted to assess the effects of statins in reducing the risk of VTE. They state that the use of statin is safe in the treatment of VTE but there is need to consider the association between adherence to statin treatment and the risk of VTE.

Introduces the clinical research articles from the vascular research group at Chieti University and Pescara (Italy) and from St. Mary's Hospital at Imperial College in London. Contributions of doctors and researchers to an international institution; Studies by the group in Chieti University, Pescara and San Valentino; Legacy with St. Mary's Hospital.

Atherosclerosis has a long preclinical phase, and the risk of cardiovascular (CV) events may be high in asymptomatic subjects. Conventional risk factors provide information for the statistical probability of developing CV events, but they lack precision in asymptomatic subjects. This review aims to summarize the role of some widely publicized indicators of early atherosclerosis in predicting CV events. The earliest measurable indicator of the atherosclerotic process is endothelial dysfunction, measured by flow-mediated dilation (FMD) of the brachial artery. However, reduced FMD is a stronger predictor of future CV events in patients with existing CV disease than in apparently healthy persons. Alternatively, measurement of carotid artery intima-media thickness does not improve the predictive value of risk factor scores, while detection of asymptomatic atherosclerotic plaques in carotid or common femoral arteries by ultrasound indicates high CV risk. Coronary calcium is a robust and validated help in the estimation of vascular changes and risk, which may improve risk stratification beyond traditional risk factors with relatively low radiation exposure. Arterial stiffness of the aorta, measured as the carotid-femoral pulse wave velocity is an independent marker of CV risk at the population level, but it is not recommended as a routine procedure because of measurement difficulties. Low ankle-brachial index (ABI) indicates flow-limiting atherosclerosis in the lower limbs and indicates high CV risk, while normal ABI does not rule out advanced asymptomatic atherosclerosis. Novel circulating biomarkers are associated with the atherosclerotic process. However, because of limited specificity, their ability to improve risk classification at present remains low. [Display omitted] • Traditional risk factors for cardiovascular (CV) disease inform on the probability of developing atherosclerosis and related CV events. • Detecting preclinical atherosclerosis enables the identification of individuals with ongoing atherosclerosis. • Preclinical atherosclerosis can be identified by functional/morphologic deterioration of the arterial wall or by circulating biomarkers. • The predictive value of indicators of preclinical atherosclerosis for future CV events is not completely elucidated. • Ankle-brachial index, calcium score, and asymptomatic plaques may improve risk stratification for CV events beyond traditional risk factors. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: The early identification of the unstable carotid plaque together with the best medical treatment, are two missing parts of the stroke-prevention puzzle. This review summarizes the available evidence on the effects of statins on carotid plaque morphology. Methods: A systematic review of the PubMed, Scopus and Cochrane Library databases was performed. Studies evaluating the effect of statins on plaque imaging features other than intima media thickness as well as on the serum inflammatory profile were eligible for inclusion. Results: Seventeen studies were eligible for inclusion. The majority of the studies used MRI and ultrasound imaging. Plaque composition (fibrous cap and lipid core size), and size (plaque area and volume) were mainly used to evaluate the changes in plaque morphology. All studies showed slower progression, remodelling or even regression of the plaque even after only 1 month of statin administration, although the type, dosage and duration of treatment varied significantly between them. Intensive statin treatment was suggested to have a more pronounced effect on plaque morphology, however, that was mainly associated with maintaining LDL-levels <100mg/mL and not with the intensity of the dosage. Seven studies measured CRP, four of which found significantly decreased levels with statin use. Conclusion: This review suggests that statins may have a beneficial effect on plaque morphology and the inflammatory response. Further validation of whether this is an LDL-associated effect or a separate pleiotropic phenomenon of statins is needed. There are significant inherent limitations to the safe extraction of solid conclusions from the studies due to data heterogeneity and publication bias. [Copyright &y& Elsevier]

The intima-media thickness (IMT) of the common carotid artery (CCA) is widely used as an early indicator of the development of cardiovascular disease (CVD). It was proposed but not thoroughly investigated that the media layer (ML) thickness (MLT), its composition, and its texture may be indicative of cardiovascular risk and for differentiating between patients with high and low risk. In this study, we investigate an automated method for segmenting the ML and the intima layer (IL) and measurement of the MLT and the intima layer thickness (ILT) in ultrasound images of the CCA. The snakes segmentation method was used and was evaluated on 100 longitudinal ultrasound images acquired from asymptomatic subjects, against manual segmentation performed by a neurovascular expert. The mean ± standard deviation (Sd) for the first and second sets of manual and the automated IMT, MLT, and ILT measurements were 0.71 ± 0.17 mm, 0.72 ± 0.17 mm, 0.67 ± 0.12 mm; 0.25 ± 0.12 mm, 0.27 ± 0.14 mm, 0.25 ± 0.11 mm; and 0.43 ± 0.10 mm, 0.44 ± 0.13 mm, and 0.42 ± 0.10 mm, respectively. There was overall no significant difference between the manual and the automated IMC, ML, and IL segmentation measurements. Therefore, the automated segmentation method proposed in this study may be used successfully in the measurement of the MLT and ILT complementing the manual measurements. MLT was also shown to increase with age (for both the manual and the automated measurements). Future research will incorporate the extraction of texture features from the segmented ML and IL bands, which may indicate the risk of future cardiovascular events. However, more work is needed for validating the proposed technique in a larger sample of subjects. [ABSTRACT FROM AUTHOR]

Recent studies have suggested that textural characteristics of the intima-media complex (IMC) may be more useful than the intima-media thickness (IMT) in evaluating cardiovascular risk. The primary aim of our study was to investigate the association between texture features of the common carotid IMC and prevalent clinical cardiovascular disease (CVD). The secondary aim was to determine whether IMT and IMC texture features vary between the left and right carotid arteries. The study was performed on 2208 longitudinal-section ultrasound images of the left (L) and right (R) common carotid artery (CCA), acquired from 569 men and 535 women out of which 125 had clinical CVD. L and R sides of the IMC were intensity normalized and despeckled. The IMC was semiautomatically delineated for all images using a semiautomated segmentation system, and 61 different texture features were extracted. The corresponding IMT semiautomated measurements (mean±SD) of the L and R sides were 0.73±0.21 mm/0.69±0.19 mm for the normal population and 0.83±0.17 mm/0.79±0.18 mm for those with CVD. IMC texture features did not differ between the right- and left-hand sides. Several texture features were independent predictors of the presence of CVD. The multivariate logistic regression analysis combining age, IMT, and texture features produced a receiver operating characteristic curve with an area under the curve of 89%. A correct classification rate of 77% for separating the normal subject (NOR) versus CVD subjects was achieved using the support vector machine classifier with a combination of clinical features, IMT, and extracted texture features. Texture features provide additional information on the presence of clinical CVD, which is over and above that provided by conventional risk factors or IMT alone. The value of IMC texture features in the prediction of future cardiovascular events should be tested in prospective studies. [ABSTRACT FROM AUTHOR]

Common carotid intima-media thickness (CIMT) is a commonly used marker for atherosclerosis and is often computed in carotid ultrasound images. An analysis of different computerized techniques for CIMT measurement and their clinical impacts on the same patient data set is lacking. Here we compared and assessed five computerized CIMT algorithms against three expert analysts' manual measurements on a data set of 1088 patients from two centers. Inter- and intra-observer variability was assessed, and the computerized CIMT values were compared with those manually obtained. The CIMT measurements were used to assess the correlation with clinical parameters, cardiovascular event prediction through a generalized linear model and the Kaplan-Meier hazard ratio. CIMT measurements obtained with a skilled analyst's segmentation and the computerized segmentation were comparable in statistical analyses, suggesting they can be used interchangeably for CIMT quantification and clinical outcome investigation. To facilitate future studies, the entire data set used is made publicly available for the community at http://dx.doi.org/10.17632/fpv535fss7.1. [ABSTRACT FROM AUTHOR]

The LONFLIT1/2 studies have established that in high-risk subjects after long (> 10 hours) flights the incidence of deep venous thrombosis (DVT) may be between 4% and 6%. The LONFLIT4 study was aimed at evaluating the control of edema and DVT prevention in Iowmedium-risk subjects. In this study prophylaxis of edema with specific travel stockings was evaluated in 2 separate studies involving flights lasting 7 hours and 10-12 hours. Part I. Subjects at Iow-medium risk for DVT were contacted; 55 subjects were excluded for several nonmedical, travel-related problems or inconvenient evaluation time; the remaining 211 were randomized into 2 groups to evaluate prophylaxis with elastic stockings in 7-8-hour, longhaul flights. The control group had no prophylaxis; the treatment group used below-knee, Sigvaris Traveno elastic stockings (Ganzoni, Switzerland, producing 12-18 mm Hg of pressure at the ankle). Color duplex scanning was used to evaluate the possible presence of DVT; edema/swelling were evaluated with a composite score including the presence of edema (with an edema tester), variations in ankle circumference and leg volumetry, subjective swelling, and discomfort (scale ranging from 0 to 10). Results: Of the 103 included subjects in the stockings group and 108 in the control group (total 211), 195 subjects completed the study. Dropouts (16) were due to low compliance or traveling and connection problems. Age, sex distribution, and risk factors distributions were comparable in the 2 groups. Stockings Group: Of 97 subjects none had DVT or superficial thromboses. Control Group: Of 98 subjects none had thrombosis. The level of edema at inclusion was comparable in the 2 groups of subjects. After flights there was an average score of 6.4 (1.3) in the control group, while in the stockings group the score was on average 2.4 (SD 1), 2.6 times lower than in the control group (p < 0.05). In the control group 83% of the subjects had an evident increase in ankle... [ABSTRACT FROM AUTHOR]

Compares the protective effects of low-molecular-weight heparin and aspirin for deep venous thrombosis (DVT) prevention in high-risk subjects in long-haul flights. Risk factors for DVT; Association between prolonged travel, DVT and pulmonary embolism; Percentage of recorded medical episodes in flight; Evidence of mild gastrointestinal symptoms in subjects taking aspirin.

Part III. Presents the management of and the role of several factors on stroke. Information regarding stroke; Discussion on thrombolysis, anticoagulant agents and prophylactic neuroprotection with pharmacologic agents; Relation with carotid endarterectomy, bypass surgery, carotid artery angioplasty and stenting; Treatment of cerebral hemorrhage; Means and possibilities of rehabilitation.

A letter to the editor is presented in response to the article "Stenting Versus Endarterectomy for Treatment of Carotid-Artery Stenosis," by T. G. Brott, R. W. Hobson II, G. Howard et al. that was published in the July 1, 2010 issue of the "New England Journal of Medicine."

We aimed to test the association between matrix metalloproteinase (MMP) genetic polymorphisms and (a) intima–media thickness in the common carotid (IMTcc) and (b) the presence of plaques in the carotid and femoral bifurcations. Carotid and femoral bifurcations were scanned with ultrasound in 762 Cypriot community dwellers (46% men) over the age of 40 years. IMTcc and the presence of plaques were recorded. The MMP1 1G/2G, MMP3 5A/6A, MMP7 -181A>G, MMP9 R279Q, and MMP12 -82A>G polymorphisms were determined with the TaqMan method. In men, the presence of plaques in any bifurcation was associated with the MMP9 279Q allele (ORadjusted=4.50; 95% CI=2.0 to 10.1; p<0.001) and the MMP7 -181A allele was associated with the presence of femoral plaques (ORadjusted=2.61; 95% CI=1.36 to 4.99; p=0.004). In women, the presence of femoral plaques was associated with the MMP12 -82G allele (ORadjusted=1.9; 95% CI=1.14 to 3.16; p=0.014). Our results suggest that the effect of common MMP genotypes on plaque presence may be site- and sex-dependent. [ABSTRACT FROM AUTHOR]

Background: We aimed to explore the association between presence and number of components of the Metabolic Syndrome (MetS) and subclinical atherosclerosis outcomes (common carotid intima media thickness, plaque presence and sum of plaque area) in both the carotid and femoral bifurcations. Methods: Cross-sectional analysis of 771 volunteers from the ongoing epidemiological Cyprus Study (46% male; mean age = 60.1 ± 9.8). (a) Carotid intima-media thickness (IMTcc), (b) sum of plaque area in the carotid bifurcations (sum of the largest plaques in each carotid bifurcation-SPAcar), (c) sum of plaque area in the femoral bifurcations (sum of the largest plaques in each femoral bifurcation-SPAfem) and (d) sum of plaque area in both carotid and femoral bifurcations (sum of the areas of the largest plaques present in each of the four bifurcations-SPA) were measured at baseline using ultrasound. Presence and number of components of the MetS was ascertained using the National Cholesterol Education Program ATPIII definition and their association tested using multivariable regression models. Results: MetS was present in 259 (33.6%) individuals and was associated with a 0.02 mm increase in IMTcc (95% CI: 0.00 to 0.04, p = 0.047) after adjustment for age, sex, family history of CVD, alcohol consumption (BU/week) and smoking (pack-years). Each additional component of the MetS was associated with a 16% higher SPA (95% CI: 6.8% to 25.2%, pfor trend = 0.001), a 10% higher SPAcar (95% CI: 5% to 24%, pfor trend = 0.003) and a 14% higher SPAfem in the adjusted model. Conclusions: We confirm an association between the MetS and IMTcc as well as report for the first time an association between the MetS and its components and femoral plaque area, in a general population over 40 years of age. Having any risk factors for the MetS increases the risk for subclinical atherosclerosis, with the risk increasing with each additional component. Using the dichotomous definition of the MetS may be overlooking the risk for subclinical atherosclerosis -and by inference future cardiovascular events- associated with having less than 3 risk factors. [ABSTRACT FROM AUTHOR]

Background: The early detection of carotid wall plaque is recommended in the prevention of cardiovascular disease (CVD) in moderate-risk patients. Previous techniques for B-mode carotid atherosclerotic wall plaque segmentation used artificial intelligence (AI) methods on monoethnic databases, where training and testing are from the "same" ethnic group ("Seen AI"). Therefore, the versatility of the system is questionable. This is the first study of its kind that uses the "Unseen AI" paradigm where training and testing are from "different" ethnic groups. We hypothesized that deep learning (DL) models should perform in 10% proximity between "Unseen AI" and "Seen AI". Methodology: Two cohorts from multi-ethnic groups (330 Japanese and 300 Hong Kong (HK)) were used for the validation of our hypothesis. We used a four-layered UNet architecture for the segmentation of the atherosclerotic wall with low plaque. "Unseen AI" (training: Japanese, testing: HK or vice versa) and "Seen AI" experiments (single ethnicity or mixed ethnicity) were performed. Evaluation was conducted by measuring the wall plaque area. Statistical tests were conducted for its stability and reliability. Results: When using the UNet DL architecture, the "Unseen AI" pair one (Training: 330 Japanese and Testing: 300 HK), the mean accuracy, dice-similarity, and correlation-coefficient were 98.55, 78.38, and 0.80 (p < 0.0001), respectively, while for "Unseen AI" pair two (Training: 300 HK and Testing: 330 Japanese), these were 98.67, 82.49, and 0.87 (p < 0.0001), respectively. Using "Seen AI", the same parameters were 99.01, 86.89 and 0.92 (p < 0.0001), respectively. Conclusion: We demonstrated that "Unseen AI" was in close proximity (<10%) to "Seen AI", validating our DL model for low atherosclerotic wall plaque segmentation. The online system runs < 1 s. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: Emerging data suggests that 3-dimensional (D) ultrasound (US) may provide us with a new tool for the identification of the vulnerable carotid plaque. Methods: A systematic review of the PubMed, Scopus and Cochrane databases regarding the reproducibility and effectiveness of 3D US in evaluation of carotid plaque disease (CPD) was performed. Results: Seven studies on the reproducibility of 3D ultrasound evaluation of plaque volume (PV) were identified. All studies reported good intra- and inter-observer reproducibility ranging from 2.8–6.0% to 4.2–7.6%, respectively. In addition, ten studies evaluating 3D carotid plaque progression with and without treatment were retrieved. In the 4 studies where 2D and 3D US features were compared, PV rather than intima media thickness (IMT) was a more sensitive marker of plaque change as a response to treatment. However, there were no studies evaluating changes in plaque morphology or specific composition features post-treatment with both 2 and 3D US. Finally, only one study was identified regarding the 3D composition differences of CPD between symptomatic and asymptomatic patients. Conclusion: The current evidence supports the good reproducibility of the 3D US on the evaluation of carotid plaque volume, however with high heterogeneity between studies. There is also preliminary evidence that PV measurements may be more sensitive than IMT in the identification of plaque change post-treatment, though, more plaque-related evidence is necessary. Further research is needed to establish if 3D is superior to 2D US in the identification of the vulnerable carotid plaque in clinical settings. [Copyright &y& Elsevier]

Objective: Metallothioneins (MTs) are antioxidant proteins expressed in response to injury. We evaluated MT immunoreactivity in carotid plaques obtained from asymptomatic and symptomatic patients. We also assessed the relationship between ultrasonic plaque echodensity, histological grading, computed tomography findings and MT expression. Methods and Results: In this ongoing prospective study, patients (n = 123, mean age (+/-SD) 68.4 +/- 7.7 years, 97 men) with high-grade carotid stenosis underwent carotid endarterectomy. Specimens were assessed histologically and immunohistochemically. Echolucent plaques (types 1+2) were more common in symptomatic patients (p < 0.0001) and had more advanced histological lesions (p < 0.0001). Echolucent plaques expressed MTs (in macrophages, fibroblasts and T-lymphocytes) significantly more than echogenic plaques (types 3+4) (all p < 0.0001). MT expression was mainly related to carotid plaque echolucency rather than the presence of symptoms. MT expression was significantly more common in advanced histological lesions. Plaques from asymptomatic or symptomatic patients with abnormal computed tomography findings also showed increased MT expression. There was a time-dependent fall in MT expression after cerebrovascular events (p < or = 0.011). Conclusions: MT overexpression may be triggered in unstable plaques as a local protective factor. There is a need to identify both causative and protective predictors of the 'vulnerable plaque' in the 'vulnerable patient'. Further studies are needed to resolve these issues. [ABSTRACT FROM AUTHOR]

Abstract: Quantitative characterisation of carotid atherosclerosis and classification into symptomatic or asymptomatic is crucial in planning optimal treatment of atheromatous plaque. The computer-aided diagnosis (CAD) system described in this paper can analyse ultrasound (US) images of carotid artery and classify them into symptomatic or asymptomatic based on their echogenicity characteristics. The CAD system consists of three modules: a) the feature extraction module, where first-order statistical (FOS) features and Laws’ texture energy can be estimated, b) the dimensionality reduction module, where the number of features can be reduced using analysis of variance (ANOVA), and c) the classifier module consisting of a neural network (NN) trained by a novel hybrid method based on genetic algorithms (GAs) along with the back propagation algorithm. The hybrid method is able to select the most robust features, to adjust automatically the NN architecture and to optimise the classification performance. The performance is measured by the accuracy, sensitivity, specificity and the area under the receiver-operating characteristic (ROC) curve. The CAD design and development is based on images from 54 symptomatic and 54 asymptomatic plaques. This study demonstrates the ability of a CAD system based on US image analysis and a hybrid trained NN to identify atheromatous plaques at high risk of stroke. (E-mail: knikita@cc.ece.ntua.gr) [Copyright &y& Elsevier]

Evaluates the incidence of deep venous thrombosis (DVT) occurring as a consequence of long flights. Absence of cardiovascular disease and drug use in low-risk subjects; Use of ultrasound scans to diagnose DVT after the flights; Absence of DVT on low-risk groups; Comparison of the incidence of DVT between subjects wearing stockings and those that do not.

The reason for the sex difference in coronary heart disease (CHD) occurrence remains enigmatic. Abdominal obesity is positively associated with CHD risk in both women and men, and it has been suggested that sex differences in fat distribution could explain much of the sex difference in CHD risk. In one study the sex difference in CHD risk largely disappeared after adjustment for waist-hip ratio. The problem with such adjustment is that any risk factor that differs considerably between men and women may statistically explain the sex difference in CHD occurrence because of collinearity in effect it becomes merely a marker for sex. This dilemma is resolved if two criteria are demonstrated. Firstly, it needs to be demonstrated that the association of abdominal obesity with CHD risk is of similar strength and is continuous across the two sexes. Secondly, it needs to be demonstrated that the sex difference in CHD risk is attenuated with adjustment for abdominal obesity.

The motion of the carotid atheromatous plaque relative to the adjacent wall may be related to the risk of cerebral events. A quantitative method for motion estimation was applied to analyse arterial wall movement from sequences of 2-D B-mode ultrasound (US) images. Image speckle patterns were tracked between successive frames using the correlation coefficient as the matching criterion. The size of the selected region-of-interest (ROI) was shown to affect the motion analysis results; an optimal size of 3.2 × 2.5 mm2 was suggested for tracking a region at the wall-lumen interface and of 6.3 × 2.5 mm2 for one within the tissue. The results showed expected cyclical motion in the radial direction and some axial movement of the arterial wall. The method can be used to study further the axial motion of the carotid artery wall and plaque and, thus, provide useful insight into the mechanisms of atherosclerosis. [Copyright &y& Elsevier]

Background: The LONFLIT1+2 studies have established that in high risk subjects after long flights (> 10 hours) the incidence of deep venous thrombosis (DVT) is between 4% and 6%. The LONFLIT4 study was designed to evaluate the control of edema and DVT in low-medium risk subjects. The aim of this study was to evaluate edema and its control with specific stockings (ankle pressure between 20 and 30 mm Hg) in long-haul flights. The first part of the study included flights lasting 7-8 hours and the second part included flights lasting 11-12 hours. Ultrasound scans were used to assess thrombosis before and after the flights and a composite edema score was used to evaluate edema and swelling. A group of patients with microangiopathy associated to edema (diabetes, venous hypertension, anti-hypertensive treatment) were also included to evaluate the preventive effects of stockings during flight. Part I: DVT evaluation: Of the 74 subjects in the stocking group and 76 in the control group (150), 144 completed the study. Dropouts were due to low compliance or traveling and connection problems. Age and gender distribution were comparable in the 3 groups as was risk factor distribution. In this part of the study there were no DVTs. Edema evaluation: The level of edema at inclusion was comparable in the two groups of subjects. After the flight there was an average score of 6.9 (1) in the control group. In the stocking group, the score was on average 2.3 (1), three times lower than in the control group (p<0.05). Part II: DVT evaluation: Of the 66 included subjects in the stocking group and 68 in the control group (134), 132 completed the study. Dropouts were due to low compliance or connection problems. Age and gender distribution were comparable in the two groups. In the stocking group no DVT was observed. In the control group, 2 subjects had a popliteal DVT and 2 subjects had superficial venous thrombosis (SVT); in total 4 subjects (6%) in the control group had a thrombotic... [ABSTRACT FROM AUTHOR]

The LONFLIT1/2 studies have established that in high-risk subjects after long (> 10 hours) flights the incidence of deep venous thrombosis (DVT) is between 4% and 6%. The LONFLIT4 study has been planned to evaluate the control of edema and DVT in low-medium-risk subjects. The aim of this study was to evaluate edema and its control with specific flight stockings, in long-haul flights. In the first part of the study 400 subjects at low-medium risk for DVT were contacted; 28 were excluded for several nonmedical problems; 372 were randomized into 2 groups to evaluate prophylaxis with stockings in 7-8-hour flights; the control group had no prophylaxis. Below-knee, Scholl, Flight Socks, producing 14-17 mm Hg of pressure at the ankle, were used in the treatment group. The occurrence of DVT was evaluated with high-resolution ultrasound scanning (femoral, popliteal, and tibial veins). Edema was assessed with a composite score based on parametric and nonparametric measurements. Part II: In this part of the study 285 subjects at low-medium risk for DVT were included and randomized into 2 groups to evaluate edema prophylaxis in 11-12-hour flights; the controls had no prophylaxis while the prevention group had below-knee, Scholl, Flight Socks (comparable to part I). Results. Part I: DVT evaluation. Of the 184 included subjects in the stockings group and 188 in the control group, 358 (96.2%) completed the study. Dropouts were due to compliance or connection problems. Age/sex distributions were comparable in the groups. Stockings Group: of 179 subjects (mean age 49; SD 7; M:F = 101:78), none had DVT or superficial thromboses. Control Group: of 179 subjects (mean age 48.4; SD 7.3; M:F = 98:81), 4 (2.2%) had a DVT. There were also 2 superficial thromboses. In total, 3.35% (6) subjects had a thrombotic event. The difference (p < 0.002) is significant. Intention-to-treat analysis detects 15 failures in the control group (9 lost + 6 thromboses) out of 188 subjects (7.9%) versus 5... [ABSTRACT FROM AUTHOR]

In this paper, a pilot study regarding carotid atherosclerotic plaque instability using B-mode ultrasound (US) images was carried out. The fractal dimension of plaques obtained from ten symptomatic subjects (i.e., subjects having experienced neurological symptoms) as well as from nine asymptomatic subjects, was estimated using a novel method, called the kth nearest neighbour (KNN) method. The results indicated a significant difference, as per the fractal dimension, between the two groups, providing a significantly lower value for the asymptomatic group. Moreover, the phase of the cardiac cycle (systole/diastole) during which the fractal dimension was estimated had no systematic effect on the calculations. The fractal dimension of the plaques was also estimated using a well-known method, namely the box-counting (BC) method. No significant differences between the two groups, as per the fractal dimension, were observed using the BC method. The presented pilot study suggests that the fractal dimension, estimated by the proposed method, could be used as a single determinant for the discrimination of symptomatic and asymptomatic subjects. (E-mail: knikita@cc.ece.ntua.gr) [Copyright &y& Elsevier]

Atherosclerosis constitutes the most common medical and surgical problem. This can be mani tested clinically as stroke, coronary artery disease, or peripheral vascular disease In the present review the microscopic appearance of the normal arterial wall, the definition of atherosclerosis and the five theories of atherogenesis are described. These are: the lipid theory, the hemodynamic theory, the florin incrustation theory, the nonspecific mesenchymal hypothesis and the response to injury hypothesis. Based on the above theories the sequence of events in athero genesis is analyzed The classification of the atherosclerotic lesions according to Stary (types I-VI) and their characteristics appear in a table. The epidemiology and the role of the following risk factors are presented in detail: age, sex, lipid abnormalities, cigarette smoking, hypertension, diabetes mellitus, physical inactivity, alcohol consumption, obesity, and hemostatic factors. In addition, less common genetically determined associations like homocystinuria. Tangier disease. Hutchinson Gilford syndrome (progeria). Werner's syndrome, radiation induced atherosclerosis and the implications of Chlamydia pneumoniae on the arterial wall are discussed. [ABSTRACT FROM AUTHOR]

Part I. Focuses the epidemiology, clinical description and risk factors of stroke. Analysis of atheroma, carotid plaque echomorphology, carotid stenosis, ulcer, variations in surface deformability and dissection; Significance of cerebral collateral circulation; Conditions predisposing to cardioembolism and cerebral hemorrhage.

The article focuses on the symptoms, diagnosis and treatment of chronic venous disease. The author reviews how the disease is manifested by a range of signs, the most obvious of which are varicose veins and venous ulcers. According to the author, chronic venous disease can be graded according to the descriptive clinical etiologic, anatomical, and pathophysiological classification, which provides an orderly framework for communication and decision making. An analysis of the prevalence of the disease is presented. A description of symptoms is included. Issues related to inflammation conditions and treatment of the disease are reviewed.