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Intima-media thickness (IMT) provides a surrogate end point of cardiovascular outcomes in clinical trials evaluating the efficacy of cardiovascular risk factor modification. Carotid artery plaque further adds to the cardiovascular risk assessment. It is defined as a focal structure that encroaches into the arterial lumen of at least 0.5 mm or 50% of the surrounding IMT value or demonstrates a thickness >1.5 mm as measured from the media-adventitia interface to the intima-lumen interface. The scientific basis for use of IMT in clinical trials and practice includes ultrasound physics, technical and disease-related principles as well as best practice on the performance, interpretation and documentation of study results. Comparison of IMT results obtained from epidemiological and interventional studies around the world relies on harmonization on approaches to carotid image acquisition and analysis. This updated consensus document delineates further criteria to distinguish early atherosclerotic plaque formation from thickening of IMT. Standardized methods will foster homogenous data collection and analysis, improve the power of randomized clinical trials incorporating IMT and plaque measurements and facilitate the merging of large databases for meta-analyses. IMT results are applied to individual patients as an integrated assessment of cardiovascular risk factors. However, this document recommends against serial monitoring in individual patients.

Background: Measurement of far wall common carotid artery intima-media thickness (CCAIMT) has emerged as a predictor of incident cardiovascular events. The Cardiovascular Risk Factor Multiple Evaluation in Latin America (CARMELA) study was the first large-scale population-based assessment of both CCAIMT and cardiovascular risk factor prevalence in 7 Latin American cities; the relationship between CCAIMT and cardiovascular risk markers was assessed in these urban Latin American centers. Methods: CARMELA was across-sectional, population-based, observational study using stratified, multistage sampling. The participants completed a questionnaire, were evaluated in a clinical visit and underwent carotid ultrasonography. Clinical measurements were obtained by health personnel trained, certified and supervised by CARMELA investigators. Mannheim intima-media thickness consensus guidelines were followed for measurement of CCAIMT. Results: In all cities and for both sexes, CCAIMT increased with higher age. CCAIMT was greater in the presence of cardiovascular risk factors than in their absence. In all cities, there was a statistically significant linear trend between increasing CCAIMT and a growing number of cardiovascular risk factors (p < 0.001). After adjustment for age and sex, metabolic syndrome was strongly associated with increased CCAIMT (p < 0.001 in all cities), as were hypercholesterolemia, obesity and diabetes (p < 0.001 in most cities). By multivariate analysis, hypertension was independently associated with an increase in CCAIMT in all cities (p < 0.01). Conclusions: CARMELA was the first large-scale population study to provide normal CCAIMT values according to age and sex in urban Latin American populations and to show CCAIMT increases in the presence of cardiovascular risk factors and metabolic syndrome.

Aim: To define reference values for mean common carotid artery intima-media thickness (CCAIMTmean) from subjects without conventional cardiovascular risk factors. Methods: This nationwide study involved cardiologists at 246 centres in France. A total of 5,433 subjects with and without conventional cardiovascular risk factors participated. Results: In subjects without risk factors, CCAIMTmean was 0.712 ± 0.122 mm in men and 0.682 ± 0.105 mm in women (p < 0.0001). Age explained 27.7% (men) and 33.9% (women) of the variance in CCAIMTmean. Each 10-year increment in age was associated with a sex-adjusted increase in CCAIMTmean of 0.049 mm. In subjects with 1 risk factor, CCAIMTmean was 0.765 ± 0.121 (p < 0.0001 vs. subjects without risk factors). CCAIMTmean increased continuously with increasing number of risk factors, irrespective of age group. In multivariable analysis, age, sex and number of cardiovascular risk factors appeared independently associated with CCAIMTmean. Conclusion: CCAIMTmean may help to identify the population at intermediate cardiovascular risk. As an integrator of both conventional and genetic cardiovascular risk factors at the individual level, its additive value versus other risk scores must be evaluated, particularly in patients in their fourth and sixth decades.

Intima-media thickness (IMT) is increasingly used as a surrogate end point of vascular outcomes in clinical trials aimed at determining the success of interventions that lower risk factors for atherosclerosis and associated diseases (stroke, myocardial infarction and peripheral artery diseases). The necessity to promote further criteria to distinguish early atherosclerotic plaque formation from thickening of IMT and to standardize IMT measurements is expressed through this updated consensus. Plaque is defined as a focal structure that encroaches into the arterial lumen of at least 0.5 mm or 50% of the surrounding IMT value or demonstrates a thickness >1.5 mm as measured from the media-adventitia interface to the intima-lumen interface. Standard use of IMT measurements is based on physics, technical and disease-related principles as well as agreements on how to perform, interpret and document study results. Harmonization of carotid image acquisition and analysis is needed for the comparison of the IMT results obtained from epidemiological and interventional studies around the world. The consensus concludes that there is no need to ‘treat IMT values’ nor to monitor IMT values in individual patients apart from exceptions named, which emphasize that inside randomized clinical trials should be performed. Although IMT has been suggested to represent an important risk marker, according to the current evidence it does not fulfill the characteristics of an accepted risk factor. Standardized methods recommended in this consensus statement will foster homogenous data collection and analysis. This will help to improve the power of randomized clinical trials incorporating IMT measurements and to facilitate the merging of large databases for meta-analyses.

Background: Cerebral infarction (CI), myocardial infarction, peripheral artery disease (PAD) and aortic atheroma are the main clinical manifestations of atherothrombosis. Long-term prevention after CI of atherothrombotic origin may require preventive measures at other sites, such as specific drug therapies, surgery, or angioplasty. Therefore the detection of other locations is potentially important. Objectives: The primary objective was to describe the other locations of atherothrombosis in patients hospitalized for a recent cerebral infarct of atherothrombotic origin. Secondary objectives were to describe their vascular risk factor profiles, and their management before and after the cerebral event. Method: This prospective, observational, multicenter survey was conducted in France between September 2003 and July 2004, mainly in neurological departments and stroke units. Results: 753 patients were included (74% men; mean age 69.3 years). Previous coronary events had occurred in 119 (16%). Previous stroke or transient ischemic attacks had occurred in 233 (31%). PAD was already known in 109 (15%). A search for other atherothrombotic locations was positive in 216 patients (29%). The minimum prevalence for any associated atherothrombotic location (either present before or identified during hospitalization) was 47.5% for any location, 33.7% for coronary artery disease, 16.6% for aortic atheroma, and 22.7% for PAD. Conclusion: Fifty percent of the patients with recent atherothrombotic CI have other locations of atherothrombosis. For this reason, a systematic search for these other locations is recommended because of the possible therapeutic consequences. However, the question of the most appropriate period for this search after the cerebral event remains unsettled.

The authors describe the design and the general, ultrasonographic, neuropsychological methodology of an observational epidemiological population survey, named REMEMBER (Registry Evaluation Memory in Buttrio e Remanzacco) conducted in the northeast of Italy in a randomized stratified sample of 1,026 subjects (554 F and 472 M) aged 55–98 years. The study was planned as cross-sectional and longitudinal survey of cognitive impairment, cardiovascular risk factors, carotid atherosclerosis in a midlife and older Italian population sample. The objectives of the first phase are to assess the prevalence of the different types of dementia, the cognitive impairment non-dementia, the cardiovascular risk factors, the carotid intima-media thickness and arterial distensibility, and of depression. The conclusions of this study will make it possible to organize preventive and interventional strategies for these epidemic conditions.

Background: Increased carotid intima media thickness (CIMT) is frequently associated with established modifiable and non-modifiable cardiovascular risk factors, and is thought to be an independent predictor of ischemic cerebrovascular and cardiac events. The presence of carotid plaque is considered an established feature of atherosclerosis. There exist few longitudinal data on the predictive role of CIMT in the occurrence of carotid plaque. Methods: We restudied the survivors of a cohort of the San Daniele Project, a large randomized general population study, investigated in 1990 regarding the prevalence and determinants of carotid atherosclerosis. Using ultrasonography, we determined in 1,193 subjects (548 men and 645 women), the common carotid IMT and the presence of non-stenotic and stenotic plaque. Results: In 795 subjects without plaques or previous ischemic events at baseline, we found in multivariate analysis that CIMT ≧1 mm, age, hypertension and history of smoking are significant predictive elements of the occurrence of a new carotid plaque. The incremental probability of plaque occurrence is greater in midlife. CIMT and age are the most predictive risk factors with ORs of 3.66 (95% CI 1.4–9.4) and 3.02 (95% CI 2.4–3.7), respectively. The ORs for hypertension and smoking account for 1.5 (95% CI 1.1–3.4) and 1.7 (95% CI 1.1–2.8), respectively. Conclusions: Age, hypertension, history of smoking and B-mode detection of CIMT increases in subjects without carotid atherosclerosis and free of previous vascular events predict the occurrence of carotid atherosclerotic plaque.

Background: Little is known about the relationship between hypercholesterolaemia and specific aetiological subtypes of brain infarction (BI). Methods: In a cross-sectional study of 492 pairs of patients with a BI proven by MRI and matched hospital controls, we determined the blood levels of triglycerides, total, HDL and LDL cholesterol, and apolipoprotein A1 and B, in the same centralized laboratory. We performed aetiological BI subtype classification. Results: Except for triglycerides, the risk of BI increased continuously with the lipid levels, without any heterogeneity between the main BI subtypes or the group on lipid-lowering therapy. The adjusted odds ratio per standard deviation in LDL cholesterol (0.93 mmol/l) was 1.74 (95% confidence interval, 1.02–2.98) in atherothrombotic strokes (n = 109) and 2.71 (95% confidence interval, 1.60–4.55) in lacunar strokes (n = 105). Eighty percent of patients were above the ATP-III guideline threshold LDL cholesterol of 2.59 mmol/l (100 mg/dl), with a major contribution of both atherothrombotic and lacunar stroke subtypes to this group. Conclusions: These findings suggest that blood lipids, particularly total and LDL cholesterol levels, are associated with all subtypes of BI, and that LDL above 2.59 mmol/l is highly prevalent.

Carotid intima-media thickness (CIMT) is a validated predictive marker of increased plaque occurrence and the incidence of major cardiovascular events. However, due to technical issues associated with the measurement of CIMT, a well-trained and certified sonographer is needed to overcome causes of variability due to the patient, device, sonographer, and quantification tool. The recently updated Mannheim consensus defined and described how to differentiate CIMT from plaques. These definitions allow for the better analysis and quantification of early atherosclerosis. Indications for CIMT measurements largely include the detection of coronary heart disease risk among intermediate-risk patients. CIMT is frequently used in clinical trials, and recent technical recommendations have been provided to improve the quality of the procedures. The final choice of a CIMT protocol depends on the purpose of the measurement, the research question at hand, the cost effectiveness, the quality of the data and the added value provided by the additional information.