[Show abstract][Hide abstract] ABSTRACT: The intima-media thickness (IMT) of the common carotid artery (CCA) is an established indicator of cardiovascular disease (CVD). There have been reports about the difference between the left and the right sides of the CCA IMT and their relation with CVD. In this paper, we propose an automated system based on image normalization, speckle reduction filtering, and snakes segmentation, for segmenting the CCA, perform IMT measurements, and provide the differences between the left and the right sides. The study was performed on 1104 longitudinal-section ultrasound images acquired from 568 men and 536 women out of which 125 had cardiovascular symptoms (CVD). A cardiovascular expert manually delineated the IMT for the normal and the CVD groups. The corresponding (normal versus CVD) IMT mean ± standard deviation values for the left and the right sides were 0.74 ± 0.24 versus 0.87 ± 0.24 mm and 0.70 ± 0.17 versus 0.80 ± 0.18 mm, respectively. The main findings of this paper can be summarized as follows: 1) there was no significant difference between the CCA left side IMT and the right side IMT. These findings suggest that the measurement of the CCA IMT on one side only is needed for the normal group (and this is in agreement with other studies); 2) there were statistical significant differences for the IMT measurements between the normal group and the CVD group for both the left and the right sides; 3) there was an increasing linear relationship of the left and the right IMT measurements with age for the normal group; and to a lesser extend for the CVD group; 4) no statistical significant differences were found between the manual and the automated IMT measurements for both sides; and 5) the best result for classification disease modeling, using support vector machines, to discriminate between the normal and the CVD groups was a 64%±3.5% correct classifications score when using both the left and the right IMT automated measurements. Further research is required for estimating differences and similarities between left and right intima media complex structure and morphology and their variability with texture features for differentiating between the normal and the CVD group.
Full-text · Article · Jul 2015 · IEEE Journal of Translational Engineering in Health and Medicine
[Show abstract][Hide abstract] ABSTRACT: To investigate the association between commonly used insulin resistance indices and presence and extent of carotid and femoral atherosclerosis in a general population setting.
Cross--sectional analysis of 762 volunteers from the ongoing epidemiological Cyprus Study (46.6% male; mean age=60.5±10.2). (a) Carotid intima--media thickness (IMTcc), (b) carotid and femoral atherosclerotic plaque presence, (c) total plaque area in the carotid/femoral bifurcations (sum of the largest plaques in each carotid/femoral bifurcation--SPAcar/fem) and (d) total 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 using ultrasound at baseline. The HOMA--IR, QUICKI and McAuley indices as well as fasting insulin levels were estimated and their quartiles were used in linear and logistic regression analysis.
All insulin resistance indices studied were strongly associated with IMTcc (p<0.01for all) even after adjustment for age and sex and exclusion of diabetic subjects. However, when looking at plaque presence and size (i.e.area) only the HOMA--IR and especially the McAuley indexwere associated with both carotid plaque presence (OR adj = 1.17;; 95%CI=1.01 to 1.36; p=0.03 and OR adj = 0.86;; 95%CI=0.74 to 0.99;; p=0.04 respectively) and area(OR adj = 0.10; 95%CI=0.008 to 0.20; p=0.03 and OR adj = --0.11; 95%CI=--0.20 to --0.009; p=0.03 respectively), after adjustment.The McAuley index remained a significant predictor of both carotid plaque presence and area even after exclusion of diabetic subjects (p=0.04).
Our results show that while all indices were associated with carotid IMT, supporting a strong role for insulin resistance in intimal--medial thickening, only the HOMA--IR and especially the McAuley indexwere associated with both carotid plaque presence and area, after adjustment. This highlights the importance of including triglyceride levels in estimating the risk for atherosclerotic plaque in the carotids as well as the possible differences in determinants for atherosclerosis between arterial sites.
No preview · Article · Feb 2015 · International angiology: a journal of the International Union of Angiology
[Show abstract][Hide abstract] ABSTRACT: The QT interval, an electrocardiographic measure reflecting myocardial repolarization, is a heritable trait. QT prolongation is a risk factor for ventricular arrhythmias and sudden cardiac death (SCD) and could indicate the presence of the potentially lethal mendelian long-QT syndrome (LQTS). Using a genome-wide association and replication study in up to 100,000 individuals, we identified 35 common variant loci associated with QT interval that collectively explain ∼8-10% of QT-interval variation and highlight the importance of calcium regulation in myocardial repolarization. Rare variant analysis of 6 new QT interval-associated loci in 298 unrelated probands with LQTS identified coding variants not found in controls but of uncertain causality and therefore requiring validation. Several newly identified loci encode proteins that physically interact with other recognized repolarization proteins. Our integration of common variant association, expression and orthogonal protein-protein interaction screens provides new insights into cardiac electrophysiology and identifies new candidate genes for ventricular arrhythmias, LQTS and SCD.
[Show abstract][Hide abstract] ABSTRACT: Peripheral arterial disease (PAD) is one of the most frequent manifestations of atherosclerosis and is associated with atherosclerosis in the coronary and carotid arteries, leading to a highly increased incidence of cardiovascular events. Major risk factors of PAD are similar to those that lead to atherosclerosis in other vascular beds. However, there are differences in the power of individual risk factors in the different vascular territories. Cigarette smoking and diabetes mellitus represent the greatest risks of PAD. For prevention of the progression of PAD and accompanying cardiovascular events similar preventative measures are used as in coronary artery disease (CAD). However, recent data indicate that there are some differences in the efficacy of drugs used in the prevention of atherotbrombotic events in PAD. Antiplatelet treatment is indicated in virtually all patients with PAD. In spite of the absence of hard evidence- based data on the long term efficacy of aspirin, it is still considered as a first line treatment and clopidogrel as an effective alternative. The new antiplatelet drugs ticagrelol and prasugrel also represent promising options for treatment of PAD. SW:in therapy is indicated to achieve the target low density lipoprotein cholesterol level of
Full-text · Article · Jun 2014 · International angiology: a journal of the International Union of Angiology
[Show abstract][Hide abstract] ABSTRACT: Aim:
The aim of the study was to test the association between circulating levels of matrix prometalloproteinase1 (pro-MMP1) and its tissue inhibitors TIMP1 and TIMP2 with prevalent cardiovascular events.
Prevalent cardiovascular events were documented in 500 participants of the Cyprus study (46% men) over the age of 40. Serum levels of pro-MMP1, TIMP1 and TIMP2 were measured with ELISA and the association between quartiles of serum levels and presence of cardiovascular disease (CVD) was tested using multivariable binary regression models.
Lower serum levels of pro-MMP1 and TIMP1 were strongly associated with presence of CVD at baseline even after adjustment for conventional risk factors (P(for trend)=0.006 and P=0.001, respectively) and inflammatory factors (P(for trend)=0.005 and P=0.002, respectively) with people in the highest quartile of pro-MMP1 having a reduced odds for cardiovascular disease by about 70% compared to the lowest quartile (OR(adjusted)=0.26; 95% CI=0.19 to 0.75; P=0.01), whereas people with TIMP1 levels >1000 ng/mL had a 75% reduced odds for CVD compared to the rest (OR(adjusted)=0.25; 95% CI=0.11 to 0.60; P(for trend)=0.002). TIMP2 levels were not associated with prevalent cardiovascular disease.
A strong association between lower levels of circulating pro-MMP1 and TIMP1 and risk of prevalent cardiovascular disease in a general population cohort over 40 years is evident, independent from common cardiovascular and inflammatory risk factors. The role of MMP1 and its tissue inhibitors, should be tested further in prospective studies of cardiovascular disease.
No preview · Article · Dec 2013 · International angiology: a journal of the International Union of Angiology
[Show abstract][Hide abstract] ABSTRACT: In the 1980s and early 1990s, ultrasonic plaque characterization was highly subjective. When the examination was performed in a dimly lit room, the gain was usually reduced by the operator; when it was performed in a brightly lit room, the gain was increased. Although the human eye could adjust to the image brightness to a certain extent, reproducible measurements of echodensity when the same patient was scanned in another room and on different equipment were not possible. Ultrasonic image normalization which has been introduced in the late 1990s has enabled us to overcome this problem.
[Show abstract][Hide abstract] ABSTRACT: The principles of 3-dimensional (3D) image reconstruction from a series of consecutive two-dimensional (2D) ultrasound images and the measurement of plaque volume and plaque surface irregularity have been described in Chaps. 16 and 17.
[Show abstract][Hide abstract] ABSTRACT: The aim of this document is to provide a clear and concise account of the evidence regarding efficacy or harm for various methods available to prevent and manage venous thromboembolism (VTE).
Full-text · Article · Apr 2013 · International angiology: a journal of the International Union of Angiology