Appropriate use criteria for carotid intima media thickness testing

Hypertensive disorders of pregnancy & vascular dysfunction

Hypertensive disorders of pregnancy (HDP) are a leading cause of maternal and fetal morbidity and mortality. One of the more severe HDP diagnoses is preeclampsia, which is recognized as a sex-specific cardiovascular risk enhancer with long-term implications for women's health, increasing lifetime risk of ischemic heart disease, stroke, and heart failure. Though the mechanisms accounting for the increased risk of cardiovascular disease following HDP are not yet well understood, vascular dysfunction has been implicated. In this perspective piece, we summarize the existing evidence for vascular dysfunction in HDP with a focus on non-invasive assessments, highlight advances in the field, and suggest future directions for improving risk stratification of women with HDP.

Plasma Adiponectin and Its Correlation with Carotid Intima-Media Thickness in Obesity and in Type 2 Diabetes and Nonalcoholic Fatty Liver Disease

Methods and Results

The study included 200 Egyptian subjects. They were divided into four equal groups: group 1: obese patients with NAFLD and T2DM (O+/NAFLD+/DM+), group 2: nonobese patients with NAFLD and T2DM (O-/NAFLD+/DM+), group 3: obese nondiabetic patients with NAFLD (O+/NAFLD+/DM-), and group 4: nonobese healthy control subjects. Plasma adiponectin was measured using ELISA (enzyme-linked immunosorbent assay) technique. Ultrasonography was used to diagnose NAFLD. CIMT was assessed using Doppler ultrasonography. Plasma adiponectin was significantly lower and CIMT was significantly higher in O+/NAFLD+/DM+, as compared with O-/NAFLD+/DM+, O+/NAFLD+/DM-, and control subjects (p < 0.001 for all). A significant negative correlation was found between adiponectin and CIMT in obese patients with NAFLD (p < 0.05), but not in patients with NAFLD and T2DM. The significant independent predictors of CIMT were diabetes duration, BMI (body mass index), albumin/creatinine ratio, and cholesterol.

Conclusion

Plasma adiponectin is inversely correlated with CIMT in obese patients with NAFLD, but not in patients with NAFLD and T2DM. Hypoadiponectinemia could be a good indicator of cardiovascular risk in obese patients with NAFLD, with or without T2DM, but not in nonobese patients with NAFLD.

The optimal WC cut-off points for the prediction of subclinical CVD as measured by carotid intima-media thickness among African adults: a cross-sectional study

BACKGROUND

Increased waist circumference (WC) is one of the cardiovascular disease (CVD) risk factors used to predict cardiovascular events. Waist circumference cut-off values for predicting metabolic syndrome and other cardiovascular risks have been previously studied. Carotid intima-media thickness (CIMT) is one of the cardiovascular risk factor recently described and reported to be suitable as it is a direct measurement of vascular quality. Hence the aim of the present study was to determine the optimal WC cut-off point for the prediction of subclinical CVD.

METHODS

The study was a cross-sectional study using quantitative methods, conducted among 1318 adults aged between 40 and 60 years old, residing in a rural Black population in Limpopo province. Carotid Intima-Media Thickness measurements were performed using a LOGIQ ultrasound system (GE Healthcare, CT, USA). Waist Circumference (WC) (cm) was measured to the nearest 0.1 cm. Bivariate correlation, logistic regression and receiver operating characteristic were analysed using the statistical package for social sciences version 26.0 software.

RESULTS

Among the total population, 69% were women and 31% men with a mean age of 53 ± 7 years. Among women, WC at a cut-off value of 95 cm gave the highest sensitivity of 57%, the specificity of 55% and an area under the curve (AUC) of 0.588. In men, an optimum WC cut-off point of 82 cm yielded the highest sensitivity and specificity at 72% and 70% respectively, with an AUC of 0.767 p < 0.001.

CONCLUSION

The traditional waist circumference cut-off points (94 cm for women and 80 cm for men) that are currently used for the diagnosis of metabolic syndrome might not be suitable in the prediction of an increased CIMT.

Hypoadiponectinemia as a marker of increased cardiovascular risk in patients with non-alcoholic fatty liver disease: correlation with albumin/creatinine ratio

OBJECTIVE

We assessed plasma adiponectin and its correlation with carotid intima-media-thickness (CIMT), as a marker of atherosclerosis, and urine albumin/creatinine ratio (ACR) in patients with non-alcoholic fatty liver disease (NAFLD).

METHODS

The study included 100 Egyptian subjects (50 patients with NAFLD with no history of diabetes or hypertension and 50 age and sex-matched normal healthy control subjects). Urine albumin/creatinine ratio (ACR) was assessed in all participants and fasting plasma adiponectin was measured using ELISA technique. Ultrasonography was used to diagnose NAFLD. CIMT was assessed using high-resolution Doppler ultrasonography.

RESULTS

Mild albuminuria was detected in patients with NAFLD (mean urine ACR = 42 ± 30 mg/g). Plasma adiponectin was significantly lower and urine ACR and CIMT significantly higher in patients with NAFLD as compared with the control group (P < 0.001 for all). A significant negative correlation was found between plasma adiponectin and both urine ACR and CIMT in patients with NAFLD (P < 0.001 and < 0.05 respectively). A significant positive correlation was also found between CIMT and urine ACR in those patients (P < 0.05). Plasma adiponectin and urine ACR were independent determinants of CIMT in patients with NAFLD (P < 0.01 and < 0.05 respectively).

CONCLUSION

Patients with NAFLD, without diabetes, have an increased risk of atherosclerosis and cardiovascular disease. Hypoadiponectinemia and low-grade albuminuria are important markers of that risk.

Clinical Significance of Carotid Intima-Media Complex and Carotid Plaque Assessment by Ultrasound for the Prediction of Adverse Cardiovascular Events in Primary and Secondary Care Patients

Recently published recommendations from the American Society of Echocardiography on 'Carotid Arterial Plaque Assessment by Ultrasound for the Characterization of Atherosclerosis and Evaluation of Cardiovascular Risk' provoked discussion once more on the potential clinical applications of carotid intima-media complex thickness (CIMT) and carotid plaque assessment in the context of cardiovascular risk in both primary and secondary care patients. This review paper addresses key issues and milestones regarding indications, assessment, technical aspects, recommendations, and interpretations of CIMT and carotid plaque findings. We discuss lacks of evidence, limitations, and possible future directions.

Remodeling of ipsilateral ulnar artery after radial artery harvesting for coronary artery bypass graft

There are controversies in the literature on the blood supply to the forearm after surgical removal of the radial artery in coronary artery bypass grafting (CABG). The objective was to investigate the arterial remodeling of the ulnar artery after the removal of the radial artery in myocardial revascularization by means of ultrasound examination with color Doppler in the pre- and post-operative periods. This paper describes an observational prospective study of the remodeling of the left brachial and ulnar arteries (donor arm) in 103 right-handed non-consecutive adult patients undergoing CABG with removal of the ipsilateral radial artery using the color Doppler ultrasound examination. In the ulnar artery, a significant increase (P < 0.05) was seen in the following measurements: lumen diameter by 13%, lumen area by 26%, peak systolic flow by 40%, and average flow by 46%. Intima-media thickness measured in the ulnar artery did not show a statistically significant difference (P = 0.22), except in diabetic patients (P = 0.007). We conclude that the ulnar artery undergoes positive physiological remodeling, adapting to the new requirements of chronic increase in flow after the ipsilateral removal of the radial artery to serve as a graft in CABG. There was no evidence of increased intima-media thickness, except in diabetic patients.

Efficacy of oral rosuvastatin intervention on HDL and its associated proteins in men with type 2 diabetes mellitus

PURPOSE

High-density lipoprotein (HDL) undergoes structural and functional modification in patients with type 2 diabetes mellitus (T2DM). There are limited data on effect of rosuvastatin on HDL-associated proteins and the antiatherogenic effects of rosuvastatin. The present study intended to study the efficacy of rosuvastatin intervention on HDL-associated proteins and its other antiatherogenic effects in men with T2DM.

METHODS

Men with T2DM on oral antidiabetic treatment, with LDL-C levels > 75 mg/dL and willing for rosuvastatin intervention (20 mg/day orally for a period of 12 weeks), were included. Fasting glucose, lipid profile were measured using standard methods. Oxidized low-density lipoprotein (oxLDL), oxidized HDL (oxHDL), paraoxonase-1 (PON-1), tumour necrosis factor-α (TNF-α) and lecithin:cholesterol acyltransferase (LCAT) in serum were measured by ELISA; serum myeloperoxidase (MPO) by spectrophotometric method and cholesterol efflux by fluorometric assay. Carotid intima-media thickness (cIMT) measurement to assess vascular health status was done using doppler.

RESULTS

Rosuvastatin produced a significant decrease (p < 0.05) in lipids (total cholesterol, triglycerides, LDL-C); oxidative stress (oxLDL, oxHDL, MPO); inflammation (TNF-α); LCAT concentration; cIMT; significant increase in antiatherogenic HDL and cholesterol efflux (p < 0.05) and no change in apoA-I levels from baseline to 12 weeks of follow-up. A decrease in MPO activity was found to be independently associated with an increase in cholesterol efflux.

CONCLUSIONS

Post intervention there is a quantitative and qualitative improvement in HDL, which helps in its reverse cholesterol transport (RCT) and antioxidant functions. Improvement in HDL functions and suppression of inflammation by rosuvastatin lead to regression in cIMT, which is beneficial in decreasing the progression of cardiovascular disease (CVD) in men with diabetes.

Has carotid intima-media thickness prognostic impact in patients with high cardiovascular risk? A long-term cohort study

BACKGROUND

Carotid intima-media thickness (CIMT) is an established surrogate marker for cardiovascular events in patients with intermediate risk. In patients with high cardiovascular risk or established cardiovascular disease, the impact of CMIT measurement on risk stratification for future events is less clear. Our objective was to evaluate the impact of CIMT on the occurrence of cardiovascular events in a cohort of individuals with high cardiovascular risk, in long-term follow-up.

METHODS

We analyzed 296 individuals, mean follow-up of 6.9 ± 2.2 years. Individuals were divided into tertiles according to CIMT. Tertiles were compared in terms of baseline characteristics and outcomes during follow-up-all-cause mortality and composite outcome (mortality, acute coronary syndromes, coronary revascularization, stroke/transient ischemic attack, heart failure, or cardiovascular admission).

RESULTS

Our population had a mean age of 65 ± 9 years at the beginning of the study, 55% males. Patients with higher CIMT showed a trend for higher cardiovascular mortality (P = 0.084) and for the composite outcome (P = 0.049). A CIMT ≥ 0.85 mm was also associated with higher rate of events; however, CIMT was not an independent predictor of outcome after adjustment for age and gender. CIMT assessment was useful in patients with hypertension, hyperlipidemia, and metabolic syndrome and in nondiabetic patients. For the composite outcome, it was also useful in females, smokers, and in patients without coronary artery disease.

CONCLUSIONS

Patients with higher CIMT have worst outcome, but this was mainly driven by age and gender. CIMT is useful as a prognostic marker in specific subsets of patients.

Can ultrasonographic measurement of carotid intima-media thickness predict hypotension after induction of general anesthesia?

Hypotension in patients under general anesthesia is prevalent and causes unfavorable outcomes. Carotid intima-media thickness (CIMT) is a surrogate marker for atherosclerosis and useful for evaluating the risk of cardiovascular diseases. We investigated the usefulness of preoperative CIMT measurement as a predictor of post-induction hypotension (PIH). The ultrasonographic measurement of CIMT was performed preoperatively on 82 patients scheduled for elective surgery under general anesthesia in a prospective, observational study. Mean blood pressure (MBP) was recorded before induction. Hypotension was defined as a 20% decrease in MBP from baseline. The ultrasonographic measurement of CIMT was unsuccessful in 2 (2.43%) patients, leaving 80 patients for analyses. Hypotension developed in 41 patients. CIMT was higher in the patient group with PIH than in the group without PIH (p < 0.001). There was statistically significant correlation between MBP decrease after induction and CIMT (r = 0.529, p < 0.0001). CIMT correlated positively with age (r = 0.739, p < 0.0001). The area under curve for CIMT was 0.753 [95% confidence interval (CI) 0.642-0.863]. The optimal cutoff value of CIMT was 0.65 mm with a sensitivity of 75.6% and a specificity of 74.4%. CIMT was an independent predictor of PIH after adjusting other factors with an odds ratio of 1.833 (95% CI 1.23-2.72; p = 0.003). The ultrasonographic imaging and measurement of CIMT can reliably predict hypotension with a 0.65-mm threshold level. We believe that the ultrasonographic measurements of CIMT may be included in point-of-care application in anesthesiology.

Carotid artery stenosis screening: where are we now?

Stroke poses a significant burden on healthcare and is the second largest cause of death globally. Both medical and surgical interventions to reduce the risk of stroke in asymptomatic patients have been shown to be effective but identifying the target at risk population is more problematic. Screening for carotid artery stenosis offers one pathway for this, as there is some correlation between risk of stroke and extent of stenosis. Identification of patients who are at risk of cardiovascular disease as well as stroke, allows initiation of effective medical treatment of modifiable risk factors to address this risk. In addition, carotid intima-media thickness is a way of assessing systemic atherosclerosis and may be valuable in risk stratification of patients for cardiovascular disease. Given the low prevalence of stenosis in the general population and the risks associated with undergoing surgical intervention, population wide screening is not recommended. This recommendation has not changed over the last 15 years, since the last major studies evaluating management and outcomes were published. However, both medical and surgical/endovascular treatments have advanced over that time. Further studies are underway to compare current treatments for the appropriate management of both symptomatic and asymptomatic patients with stenosis. Two of these trials, ECST-2 and CREST-2, are expected to be completed in the next 2-4 years and the results may initiate changes in the recommendations. The use of carotid intima-media thickness alongside traditional risk scores is controversial and more research is required in this area.

Factors associated with carotid Intima media thickness and carotid plaque score in community-dwelling and non-diabetic individuals

Background

The carotid intima media thickness (cIMT) and carotid plaque score (cPS) are respective markers of early and late stage subclinical atherosclerosis. Relationships between some laboratory parameters and subclinical atherosclerosis are not yet clear in community dwelling individuals and non-diabetic subjects, so we try to elucidate these relationships and find a model to predict early and late stage subclinical atherosclerosis.

Methods

We examined relationships of the cIMT and cPS with different laboratory and demographic data of 331 subjects from a community-based prospective cohort study, using univariate and multivariate analyses.

Results

In regression models and after multiple adjustments, only systolic blood pressure (SBP), age, glycated hemoglobin (HBA1c), and waist circumference (WC) were determinants of the cIMT, and only age, SBP, HBA1c, and blood urea nitrogen (BUN) were determinants of a cPS of > 2 in all individuals. Only HBA1c lost its association with regard to predicting the cIMT in non-diabetic subjects.

Conclusions

HBA1c at > 5.9% can determine early and late stage subclinical atherosclerosis in community dwelling individuals, but only late stage subclinical atherosclerosis in non-diabetic subjects.

Assessment and relevance of carotid intima-media thickness (C-IMT) in primary and secondary cardiovascular prevention

Interventions aimed to prevent cardiovascular diseases (CVD) are more effective if administered to subjects carefully selected according to their CVD risk. Usually, this risk is evaluated on the basis of the presence and severity of conventional vascular risk factors (VRFs); however, atherosclerosis, the main pathologic substrate of CVD, is not directly revealed by VRFs. The measurement of the arterial wall, using imaging techniques, has increased the early identification of individuals prone to develop atherosclerosis and to quantify its changes over time.

B-mode ultrasound is a technique which allows a non-invasive assessment of the arterial wall of peripheral arteries (e.g. extracranial carotid arteries), and provides measures of the intima-media thickness complex (C-IMT) and additional data on the occurrence, localization and morphology of plaques.

Being an independent predictor of vascular events, C-IMT has been considered as a tool to optimize the estimation of CVD risk but this application is still a matter of debate. Though the technique is innocuous, relatively inexpensive and repeatable, its use in the clinical practice is limited by the lack of standardized protocols and clear guidelines.

This review outlines the rationale for the potential use of C-IMT in the stratification of cardio- and cerebro-vascular risk and discusses several topics related to the measurement of this variable, which are still controversial among experts of the field.

The value of noncoronary atherosclerosis for identifying coronary artery disease: results of the Leipzig LIFE Heart Study

Background

Despite the widespread use of noninvasive testing prior to invasive coronary diagnostic the diagnostic yield of elective coronary angiography has been reported low in subjects with suspected obstructive CAD.

Objective

To determine the predictive value of noncoronary atherosclerosis (NCA) in subjects with suspected stable coronary artery disease (CAD) intended to invasive coronary angiography.

Methods

Ultrasound-based assessment of carotid artery plaque (CAP), carotid intima-media thickness (CIMT) and ankle-brachial index (ABI) was performed in 2216 subjects with suspected CAD prior to coronary angiography. Logistic regression and c-statistics were used to analyze the diagnostic value of NCA for the presence of obstructive CAD and the intention to revascularization.

Results

Percentage of positive results of elective coronary angiography was low but comparable to other studies (41 % obstructive CAD). We identified 1323 subjects (60 %) with NCA, most of them were characterized by CAP (93 %). CAP independently predicted obstructive CAD in addition to traditional risk factors and clinical factors while CIMT and ABI failed to improve the prediction. The presence of NCA and typical angina were the strongest predictors for obstructive CAD (OR 4.0 and 2.4, respectively). A large subgroup of patients (n = 703, 32 %) with atypical clinical presentation and lack of NCA revealed a low indication for revascularization <15 % indicating a large proportion of subjects with non-obstructive CAD in this subgroup.

Conclusion

The evaluation of noncoronary atherosclerosis has the potential to impact clinical decision making and to direct subsequent diagnostic procedures in subjects with suspected coronary artery disease.

Clinical trial registration

NCT00497887.

Electronic supplementary material

The online version of this article (doi:10.1007/s00392-015-0900-x) contains supplementary material, which is available to authorized users.

Can the ankle brachial pressure index (ABPI) and carotis intima media thickness (CIMT) be new early stage markers of subclinical atherosclerosis in patients with rheumatoid arthritis?

BACKGROUND

It takes years for atherosclerosis to manifest symptoms. However, it needs to be identified earlier because of the premature cardiovascular risk factors in patients with rheumatoid arthritis (RA). In this study, we aimed to investigate the effect of atherosclerosis on the ankle brachial pressure index (ABPI) and carotis intima media thickness (CIMT) in patients with RA.

METHODS

RA patients attending the rheumatology clinic were examined retrospectively; then we called them for the measurements of ABPI and CIMT prospectively. Subjects were divided into four groups, as follows (Table 1): group 1 comprised RA patients with an ABPI less than 0.9; group 2 included RA patients with an ABPI between 0.9 and 1.2; group 3 was made up of RA patients with an ABPI greater than 1.2; and group 4 included patients without RA with an ABPI between 0.9 and 1.2 as a control group. Patients' demographic data were recorded. Hypertension (HT), diabetes mellitus, ABPI and CIMT measurements were taken by specialists. Duration of RA and disease scores (disease activity score-28, health assessment questionnaire score and visual assessment score) were recorded.

RESULTS

The prevalence of peripheral vascular disease in patients with RA was twice as high as that in the normal population of equivalent age. Patients in group 2, with RA and normal ABPI, exhibited a significant higher mean in CIMT (mm) compared with the control group (p < 0.01), despite having normal ABPI. This confirms that these patients have a higher risk of stroke compared with the control group. Group 1's newly diagnosed HT (p < 0.01) and systolic blood pressure (SBP) values (p < 0.01) were higher and statistically significant when compared with the group 4 (control group); in addition, significant plaque levels were observed in the carotid arteries (p < 0.01). Group 3 patients had a similar history of HT and increased SBP compared with patients in group 4 (p < 0.01), and had similar characteristics to with group 1. No statistically significant differences were found between the groups in terms of inflammatory markers such as C-reactive protein and rheumatoid factor, anti-cyclic citrullinated peptide and white blood cell counts.

CONCLUSION

Based on the present findings, patients with RA need to be evaluated in the early stage of the disease for subclinical peripheral artery disease using the ABPI, as well as CIMT, which is also a non-invasive technique, in terms of cerebrovascular events. Inflammatory markers exhibited no statistically significant difference. We think that the atherosclerotic process stems not only from the inflammatory effects of RA, but also perhaps from its immunological nature.

Carotid intima-media thickness value distributions in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)

OBJECTIVE

Carotid intima-media thickness (IMT) is a noninvasive measurement of early atherosclerosis. Most IMT studies have involved populations with low rates of racial blending. The aim of the present article is to describe IMT value distributions and analyze the influence of sex and race on IMT values in a large Brazilian sample, a setting with a high rate of racial admixture.

METHODS

The Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) is a multicenter cohort of 15,105 adult (aged 35-74 years) civil servants in six Brazilian cities. Baseline assessment included IMT measurements in both common carotid arteries. Race was self-reported. We studied the association between sex and race with IMT values using multiple linear regression models. We conducted analyses in all and low-risk individuals, defined as those without classical cardiovascular risk factors.

RESULTS

We analyzed complete IMT data from 10,405 ELSA-Brasil participants. We present nomograms by age for all and low-risk individuals, stratified by sex and race. We found that men had significantly higher maximal IMT values compared with women (β = 0.058; P < 0.001). This association remained for low-risk individuals (β = 0.027; P = 0.001). In addition, Brown and White individuals had lower maximal IMT values compared with Black individuals for all (β = -0.034 and β = -0.054, respectively; P < 0.001) and low-risk individuals (β = -0.027; P = 0.013 and β = -0.035; P < 0.001, respectively).

CONCLUSION

We found significantly higher IMT values in men. We found significantly higher IMT values in Black individuals than White and Brown individuals. These results persisted when analyses were restricted to low-risk individuals.

A perspective on the New American College of Cardiology/American Heart Association guidelines for cardiovascular risk assessment

The recently published American College of Cardiology (ACC)/American Heart Association (AHA) guidelines for cardiovascular risk assessment provide equations to estimate the 10-year and lifetime atherosclerotic cardiovascular disease (ASCVD) risk in African Americans and non-Hispanic whites, include stroke as an adverse cardiovascular outcome, and emphasize shared decision making. The guidelines provide a valuable framework that can be adapted on the basis of clinical judgment and individual/institutional expertise. In this review, we provide a perspective on the new guidelines, highlighting what is new, what is controversial, and potential adaptations. We recommend obtaining family history of ASCVD at the time of estimating ASCVD risk and consideration of imaging to assess subclinical disease burden in patients at intermediate risk. In addition to the adjuncts for ASCVD risk estimation recommended in the guidelines, measures that may be useful in refining risk estimates include carotid ultrasonography, aortic pulse wave velocity, and serum lipoprotein(a) levels. Finally, we stress the need for research efforts to improve assessment of ASCVD risk given the suboptimal performance of available risk algorithms and suggest potential future directions in this regard.

Neurosonological Examination: A Non-Invasive Approach for the Detection of Cerebrovascular Impairment in AD

There has been a growing interest in vascular impairment associated with Alzheimer’s disease (AD). This interest was stimulated by the findings of higher incidence of vascular risk factors in AD. Signs of vascular impairment were investigated notably in the field of imaging methods. Our aim was to explore ultrasonographic studies of extra- and intracranial vessels in patients with AD and mild cognitive impairment (MCI) and define implications for diagnosis, treatment, and prevention of the disease. The most frequently studied parameters with extracranial ultrasound are intima-media thickness in common carotid artery, carotid atherosclerosis, and total cerebral blood flow. The transcranial ultrasound concentrates mostly on flow velocities, pulsatility indices, cerebrovascular reserve capacity, and cerebral microembolization. Studies suggest that there is morphological and functional impairment of cerebral circulation in AD compared to healthy subjects. Ultrasound as a non-invasive method could be potentially useful in identifying individuals in a higher risk of progression of cognitive decline.

Carotid intima-media thickness: Current evidence, practices, and Indian experience

As the developed and developing nations cope up with increasing predisposition to cardiovascular diseases (CVD) by adopting lifestyle changes the burden of coronary artery disease continues to rise globally. The presence of modifiable risk factors, which account for more than 90% of the cardiovascular (CV) risk, cannot always be interpreted as the presence of atherosclerotic heart disease and absence of modifiable risk factors do not guarantee absence of atherosclerotic changes in the arterial tree. Increasing awareness about primordial prevention and primary prevention of CVD is of vital importance in such scenarios. Ultrasonographic measurement of intima media thickness has been reported as a procedure to detect the early stages of atherosclerosis. Carotid intima media thickness (CIMT) testing is a safe, noninvasive and cost effective method to detect early atherosclerotic vascular diseases. This method of CV risk evaluation drew attention worldwide and of Indian physicians because of its feasibility in Indian population. Hence, detection and management of atherosclerosis in asymptomatic individuals will go a long way in preventing atherosclerotic diseases and prolonging survival and improving quality of life.

Carotid intima-media thickness testing as an asymptomatic cardiovascular disease identifier and method for making therapeutic decisions

Cardiovascular disease (CVD) is the leading cause of death and disability in the United States. Although current therapies can reduce the risk for CVD, they are only given to patients who are considered to be at risk, and are therefore only beneficial if a patient's risk is accurately predicted before he or she sustains a cardiovascular (CV) event. Unfortunately, even relatively accurate risk factor analyses, such as the Reynolds Risk Score algorithm, fail to identify some patients who will sustain a CV event within 10 years. In contrast, the presence of an atheroma is an absolute predictor for the potential of an atherothrombotic event to occur, and it is therefore reasonable to anchor clinical decisions based on this knowledge. Carotid intima-media thickness (CIMT) testing via B-mode ultrasound is a safe, simple, and inexpensive method for evaluating CV risk by measuring the combined thickness of the intimal and medial layers of the arterial wall. Use of CIMT testing can also detect marked thickening of the arterial wall, possibly indicating plaques or atheromas that are associated with accelerated atherosclerotic disease and increased risk for coronary artery disease, myocardial infarction, and stroke. These characteristics make CIMT a practical supplemental method that physicians can use when making decisions. Moreover, the ability of CIMT testing to identify and quantify atherosclerotic disease has led to the adoption of CIMT as a surrogate endpoint in clinical trials, allowing the efficacy of new drugs to be assessed much more rapidly than would be possible by focusing solely on CV event or mortality rates. To date, several trials have provided evidence to indicate that some CVD therapies slow, stop, or reverse the progression of CIMT. Although many of these studies show that changes in CIMT predict future CV events, the value of CIMT testing in CVD risk assessment is still vigorously debated. In this article, we clarify the utility of CIMT testing for risk classification and reexamine its usefulness as a method for assessing therapeutic efficacy.

Ultrasonography of carotid plaque for the prevention of stroke

A carotid ultrasonography is a non-invasive technique that provides an accurate and reliable characterization of the broad spectrum of carotid arteriosclerosis, from the intima-media thickness to the atherosclerotic plaque. Carotid ultrasonography has become a useful tool for identifying patients at high risk of stroke and selecting those who can benefit most from revascularization therapies such as carotid endarterectomy and stenting. In addition to the degree of stenosis, plaque echomorphology has emerged in recent years as an important contributory factor to stroke risk. Changes in plaque echogenicity, as measured by the quantitative computer-assisted ultrasonography index, could be a marker of plaque instability as well as an indicator of plaque remodeling, thereby providing the means for monitoring anti-atherosclerosis drugs such as statins.

Common carotid intima-media thickness does not add to Framingham risk score in individuals with diabetes mellitus: the USE-IMT initiative

AIMS/HYPOTHESIS

The aim of this work was to investigate whether measurement of the mean common carotid intima-media thickness (CIMT) improves cardiovascular risk prediction in individuals with diabetes.

METHODS

We performed a subanalysis among 4,220 individuals with diabetes in a large ongoing individual participant data meta-analysis involving 56,194 subjects from 17 population-based cohorts worldwide. We first refitted the risk factors of the Framingham heart risk score on the individuals without previous cardiovascular disease (baseline model) and then expanded this model with the mean common CIMT (CIMT model). The absolute 10 year risk for developing a myocardial infarction or stroke was estimated from both models. In individuals with diabetes we compared discrimination and calibration of the two models. Reclassification of individuals with diabetes was based on allocation to another cardiovascular risk category when mean common CIMT was added.

RESULTS

During a median follow-up of 8.7 years, 684 first-time cardiovascular events occurred among the population with diabetes. The C statistic was 0.67 for the Framingham model and 0.68 for the CIMT model. The absolute 10 year risk for developing a myocardial infarction or stroke was 16% in both models. There was no net reclassification improvement with the addition of mean common CIMT (1.7%; 95% CI -1.8, 3.8). There were no differences in the results between men and women.

CONCLUSIONS/INTERPRETATION

There is no improvement in risk prediction in individuals with diabetes when measurement of the mean common CIMT is added to the Framingham risk score. Therefore, this measurement is not recommended for improving individual cardiovascular risk stratification in individuals with diabetes.

Assessment of subclinical atherosclerosis by carotid intima media thickness: technical issues

Carotid intima-media thickness assessed by ultrasonography of carotid arteries is a safe, non-expensive, feasible and accurate method for detecting early signs of atherosclerosis and carotid intima-media thickness and change in carotid intima-media thickness over time reflect cardiovascular disease risk. Technical aspects impact on the measurement, variability and interpretation of carotid intima-media thickness. These include device aspects, inter- and intra-sonographer variability and the ultrasound protocol used. The mean common carotid intima-media thickness and the mean maximum common carotid intima-media thickness are the most widely used carotid intima-media thickness measurements. Common carotid intima-media thickness values of around 0.5 mm are considered 'normal' in young adults. Values are higher in men than in women, in African-Americans than Caucasians and increase with age. Carotid intima-media thickness values at or above the 75th percentile of a reference population indicate increased cardiovascular risk. Guidelines differ in their recommendations for the use of carotid intima-media thickness measurements for risk assessment in primary prevention because evidence suggesting that it improves upon conventional risk scores is inconsistent. Carotid intima-media thickness is frequently used in clinical trials as a surrogate endpoint for cardiovascular events on the assumption that regression or slowed progression of carotid intima-media thickness, induced by cardiovascular risk interventions, reflects a reduction in cardiovascular events. However, further data are required to confirm this linear relationship. No international guidelines exist on the use of carotid intima-media thickness as a research tool. Quality control in acquisition, measurement and interpretation of carotid intima-media thickness are important considerations and the carotid intima-media thickness protocol used should be determined by the research question under investigation.

Mannheim carotid intima-media thickness and plaque consensus (2004-2006-2011). An update on behalf of the advisory board of the 3rd, 4th and 5th watching the risk symposia, at the 13th, 15th and 20th European Stroke Conferences, Mannheim, Germany, 2004, Brussels, Belgium, 2006, and Hamburg, Germany, 2011

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.

Protocol for measuring carotid intima-media thickness that best correlates with cardiovascular risk and target organ damage

BACKGROUND

To assess which measurement of common carotid intima-media thickness (CC-IMT) is associated to a greater overall cardiovascular risk (CVR), and vascular cardiac and renal target organ damage (TOD), in diabetic, hypertensive patients and healthy subjects.

METHODS

A cross-sectional study, inclusion of 305 patients (113 hypertensive, 100 diabetics, and 92 healthy), aged 30-75 years.

MEASUREMENTS

Mean CC-IMT and maximum CC-IMT in near and far walls and in the anterior, lateral and posterior projections. Ankle/brachial index (ABI), pulse wave velocity (PWV), glomerular filtration rate (GFR), albumin/creatinine ratio, Cornell voltage-duration product (VDP) and CVR with the Framingham equation and the SCORE.

RESULTS

CC-IMT shows a positive correlation with CVR, PWV, and Cornell VDP, and a negative correlation with ABI and GFR (P < 0.001), with no difference between mean and maximum values, near and far wall, or projections. The odds ratio (OR) for the presence of TOD was greatest in mean CC-IMT (OR = 1.85 (95% confidence interval (CI): 1.335-2.58)) and lowest in maximum CC-IMT in the posterior projections OR = 1.42 (95% CI: 1.12-1.80). For each unit increase in mean CC-IMT, a risk increase by 1.98 may be expected (95% CI: 0.69-3.26), whereas the risk increase for each unit increase in maximum CC-IMT is 1.75 (95% CI: 0.70-2.79) (P < 0.001) with Framingham and with no significant association with SCORE.

CONCLUSIONS

The CC-IMT measurement protocol best predicting for the occurrence of TOD and CVR estimated with Framingham is the mean of 120 measures of mean values in the near and far walls in all three projections of both carotid arteries.

Evaluation of carotid intima-media thickness, a marker of subclinical atherosclerosis, in children with cerebral palsy

BACKGROUND

Respiratory and cardiovascular diseases are the most common causes of death in children with cerebral palsy.

OBJECTIVE

To evaluate sonographic carotid intima-media thickness, an early marker of atherosclerosis, in children with cerebral palsy and in healthy controls.

MATERIALS AND METHODS

One hundred children with cerebral palsy (65 boys), mean age 6.2 (SD, 2.1) years, and 35 age-matched and sex-matched healthy controls were included. Common carotid artery intima-media thickness was measured sonographically. Differences between patients and controls were evaluated with an independent samples t-test.

RESULTS

Age, sex distribution and levels of serum lipids were comparable between patients and controls. Average, right and left carotid artery intima-media were thicker in patients compared with controls (mean ± SD, 0.61 ± 0.13 mm vs 0.40 ± 0.03 mm; 0.61 ± 0.14 mm vs 0.40 ± 0.03 mm; 0.61 ± 0.13 mm vs 0.40 ± 0.03 mm, respectively; all P < 0.001).

CONCLUSION

Carotid intima-media is sonographically thicker in children with cerebral palsy compared with healthy controls, which may express an increased risk of atherosclerotic diseases.

PET imaging of aortic atherosclerosis: Is combined imaging of plaque anatomy and function an amaranthine quest or conceivable reality?

Traditionally, blood vessels have been studied using contrast luminography to determine the site, extent and severity of luminal compromise by atherosclerotic deposits. Similar anatomical data can now be acquired non-invasively using ultrasound, computed tomography or magnetic resonance imaging. Plaque stability is an important determinant of subsequent vascular events and currently functional data on the stability of plaque is less well provided by these methods. The search for non-invasive techniques to image combined plaque anatomy and function has been pursued with visionary anticipation. This expectation may soon be realised as imaging with radionuclide-labelled atheroma-targeted contrast agents has demonstrated that plaque functional characteristics can now be shown. Increasingly positron emission tomography/computed tomography (PET/CT) imaging with (18)F fluorodexoyglucose (FDG) and other radionuclides is being used to determine culprit plaques in complex clinically scenarios. Clinically, this information may prove extremely valuable in the assessment of stable and unstable patients and its use in prime time medical practice is eagerly awaited. We will discuss the current clinical applications of functional atheroma imaging in the aorta and highlight the promising preclinical data on novel image biomarkers of plaque instability. If clinical science is able to successfully translate these advances in vascular imaging from the bench to the bedside, a new paradigm will be achieved in cardiovascular diagnostics.