Carotid wall thickness and stroke risk in patients with asymptomatic internal carotid stenosis

The association of stroke risk factors with the future thickness of carotid atherosclerotic plaques

OBJECTIVES

An advancing atherosclerotic plaque is a risk factor for stroke. We conducted this study to assess the relationship between risk factors of stroke with changing in the thickness of carotid plaques thickness evident on sonography.

METHODS

We carried out a secondary analysis of data from a study on carotid bifurcation plaques. Data were collected in the sonography laboratories of two university hospitals. In total, 564 (240; 42.6% men) patients with atherosclerotic plaques in the carotid bifurcation and internal carotid artery with stenosis ≥ 30% evident on duplex sonography were included. We developed machine learning models using an extreme gradient boosting algorithm with Shapley additive explanation method to find important risk factors and their interactions. The outcome was a change in the carotid plaque thickness after 36 months, and the predictors were initial plaque thickness and the risk factors of stroke.

RESULTS

Two regression models were developed for left and right carotid arteries. The R-squared values were 0.964 for the left, and 0.993 for the right model. Overall, the three top features were BMI, age, and initial plaque thickness for both left and right plaques. However, the risk factors of stroke showed stronger interaction in predicting plaque thickening of the left carotid more than the right carotid artery.

DISCUSSION

The effect of each predictor on plaque thickness is complicated by interactions with other risk factors, particularly for the left carotid artery. The side of carotid artery involvement should be considered for stroke prevention.

Carotid Artery Plaque Progression: Proposal of a New Predictive Score and Role of Carotid Intima-Media Thickness

Background: We aimed to investigate if the carotid intima-media thickness (IMT) at baseline and the HAD₂S score, composed of the sum of single risk factors (hypertension, age ≥ 75 years, diabetes, dyslipidemia, smoking), were predictive of plaque progression. Methods: We performed a retrospective analysis on real-life prospectively collected data from patients with any detectable carotid plaque at follow up. The plaque score, calculated at baseline (T0) and at a median follow up of 36.6 months (IQR 39.6–34.3) (T3), was defined as 0: no plaque or stenosis < 30%; 1: stenosis in the range 30–49%; 2: in the range 50–69%; 3: in the range 70–99% and 4: occlusion. Carotid IMT was measured at T0 and T3; HAD₂S score was calculated at baseline. Results: We included 340 patients with a mean age of 69.9 (9.1) years and 25.3% subjects had plaque progression. Individuals with progression had a median HAD₂S score of 3 (1) while those without progression had 2 (1). Patients with progression had a mean baseline IMT of 0.86 (0.17) while those without progression had 0.77 (0.18) (p < 0.0001). A correlation between progression and baseline IMT was found (p = 0.002). Conclusion: Baseline IMT could be considered a predictor of progression. Patients with progression had an HAD₂S score higher than those without evolution.

Enzyme-inducing antiseizure medication utilization in patients with epilepsy and vascular risk factors

OBJECTIVES

Several lines of evidence have suggested that exposure to enzyme-inducing antiseizure medications (EIASMs) may result in the subsequent development of hyperlipidemia, a well-known risk factor for vascular disease. This may be an issue of concern particularly in the context of additional comorbid vascular risk factors. We therefore aimed to investigate trends of and associations with the use of these medications among adult patients with epilepsy.

METHODS

The cross-sectional Medical Expenditure Panel Survey (MEPS) was interrogated to ascertain the prevalence of use of EIASMs by noninstitutionalized adult patients with epilepsy in the United States between the years 2004 and 2015. Any patient prescribed carbamazepine, phenytoin, phenobarbital, or primidone within a given year was defined as having been prescribed an EIASM. Trends over three-year epochs were evaluated with univariate logistic regression, while associations with demographic factors, vascular risk factors, and vascular disease were evaluated using a chi-square test corrected for survey design as well as multivariate logistic regression.

RESULTS

A total of 2281 (unweighted) patients were identified, representing 1,781,237 individuals. Between 2004 and 2015, 45.9% (95% confidence interval [CI]: 42.4%-49.4%) were prescribed EIASMs. Approximately one-quarter of patients aged 65 years and above used EIASMs compared with 18.5% of younger patients (odds ratio [OR]: 1.83, 95% CI = 1.27-2.65). Female patients (OR = 0.61, 95% CI = 0.47-0.79) and those with heart disease (OR: 0.63, 95% CI = 0.45-0.89) were significantly less likely to be prescribed EIASMs. Among those prescribed EIASMs, 38.9% had hypertension, 12.2% had diabetes, 61.6% were overweight or obese, 17.3% heart disease, 17.2% had a history of a cerebrovascular event, and 28.5% had diagnosed hyperlipidemia. Nonetheless, between 2004-2006 and 2013-2015, the odds of EIASM prescription decreased significantly (OR: 0.39, 95% CI: 0.28-0.55).

CONCLUSIONS

A substantial proportion of patients with comorbid vascular disease or vascular risk factors (e.g., hypertension and older age) is prescribed EIASMs. This could potentially increase patients' risk for subsequent negative outcomes such as cardiovascular or cerebrovascular disease. Though utilization of these medications has decreased, further efforts toward increasing use of newer antiseizure medications (ASMs) that are not associated with similar risks may be warranted.

Relationship between ischemic stroke locations, etiology subtypes, neurological outcomes, and autonomic cardiac function

BACKGROUND

Post-stroke autonomic nervous dysfunction measured with heart rate variability (HRV) is correlated with the traditional risk factors and poor outcome. This study aimed to investigate the association between HRV and infarct locations, etiology subtypes, and neurological functional outcomes in patients with acute ischemic stroke (AIS).

METHODS

In this prospective observational study, 186 consecutive patients were assigned to four major stroke severity categories based on the National Institutes of Health Stroke Scale score (NIHSS) and the modified Rankin Scale score (mRS): mild (NIHSS 0-4) stroke, moderate (NIHSS 5-14) stroke, 'favorable' (mRS 0-2) group, and 'unfavorable' (mRS 3-5) group. HRV time domain parameters were applied to evaluate the autonomic function of patients within 1 week after admission. All patients were classified into different etiology subtypes based on the TOAST (modified Trial of ORG 10172 in Acute Stroke Treatment) classification. The association of HRV with stroke location, etiology subtypes, neurological outcome was explored for all participants. Univariate and multivariate analyses were applied to explore the prediction value of HRV.

RESULTS

160 participants had large artery atherosclerotic infarction (LAA), 61 had right internal carotid artery system infarction (R-ICA), and 61 had vertebrobasilar artery system infarction (VB). Root-mean-square of differences (RMSSD) of adjacent RR intervals and the proportion calculated by dividing the interbeat interval differences >50 ms (pNN50) in patients of VB group was significantly lower than those of patients in R-ICA group (P < 0.01).  HRV parameters in the LAA group was significantly lower than non-LAA group (P < 0.01). At discharge, significant lower HRV presented in the unfavorable group and moderate group (P < 0.05). After logistic univariate and multivariate analysis, lower SDNN (OR = 1.019; 95% CI = 1.003-1.035; p= 0.021) was independently associated with unfavorable mRS and higher NIHSS at discharge (OR = 1.013; 95%CI = 1.003-1.024; p= 0.015). Only SDNN showed predictive value for mRS≥3 (OR = 1.012; 95%CI = 1.002-1.022; p= 0.016) at 1 year.

CONCLUSIONS

HRV measured after admission is related to the AIS infarction basin, TOAST subtypes, and neurological outcomes at discharge suggesting a possible role for HRV in evaluating AIS and identifying high-risk patients.

Diagnostic Role of Carotid Intima-Media Thickness for Coronary Artery Disease: A Meta-Analysis

Background

The present meta-analysis was conducted to confirm whether carotid intima-media thickness (IMT) could serve as an accurate diagnostic method for coronary artery disease (CAD).

Methods

Databases of PubMed, Google Scholar, and Embase were searched for potential articles. The articles were selected according to inclusion criteria. Pooled sensitivity and specificity with corresponding 95% confidence interval (CI) were used to confirm the diagnostic role of IMT for CAD. I ² and P value were used to assess the existence of heterogeneity. I ² and P value were used to assess the existence of heterogeneity.

Results

22 eligible articles were selected in the present meta-analysis. Pooled sensitivity and specificity of IMT for diagnosing CAD were 0.68 (0.57-0.77) and 0.70 (0.64-0.75), respectively. The corresponding AUC was 0.74 (0.70-0.78). Subgroup analyses based on cutoff value of IMT were performed. A cutoff value of 1 mm was demonstrated to be much more accurate diagnostic criteria for CAD (sensitivity: 0.66; specificity: 0.79; AUC: 0.80). Sensitivity analysis indicated that the pooled results were robust. Deek's funnel plot indicated no significant publication bias (P value were used to assess the existence of heterogeneity.

Conclusion

Carotid IMT may serve as an accurate diagnostic tool. A cutoff value of 1 mm seems to provide much more accurate diagnostic results for CAD.

The Association of Autonomic Nervous System Function With Ischemic Stroke, and Treatment Strategies

Acute ischemic stroke, especially minor stroke, and transient ischemic attack have high risks of recurrence and exacerbation into severe ischemic strokes. It remains challenging to perform risk stratification and screen high-risk groups for initiation of early treatment in these patients. Moreover, with the growing population of patients with chronic small vessel disease, the mechanisms and clinical implications require further investigation. Traditional tools such as the ABCD2 score (age, blood pressure, clinical features, duration of symptoms, diabetes) have only moderate predictive value in patients with transient ischemic attack or minor stroke. By contrast, measurement of changes in heart rate variability (HRV) is an important and novel tool for risk stratification and outcome prediction in patients with cardiovascular diseases, as it reflects the overall level of autonomic nervous system dysfunction. Thus, abnormal HRV may be useful for prognosis and improve stratification of stroke patients with diverse risks. HRV may also partially explain autonomic nervous dysfunction and other manifestations during the process of chronic cerebral small vessel disease. In summary, measurement of HRV may contribute to early initiation of interventions in acute or chronic stroke patients using novel treatments involving rebalancing of autonomic nervous system function.

Predicting Long-Term Cardiovascular Events after Transient Ischemic Attacks: Carotid Artery Intima-Media Thickness or ABCD2 Score or Both?

Background

Patients who experienced transient ischemic attack (TIA) are at high-risk for cardiovascular events. This study aims to evaluate diagnostic value of carotid artery intima-media thickness (CIMT) and ABCD2 score for predicting cardiovascular events in long-term follow-up after TIA. We prospectively included sixty patients with TIA who admitted to hospital from March 2016 to August 2016.

Methods

Duplex ultrasonography of internal carotid arteries was performed. ABCD2 scores were evaluated for each patient. At a median follow-up of 20 months, patients were asked about new cardiovascular events. We used IBM SPSS software version 22.0 with Chi-squared, t-test, ANOVA, receiver operating characteristic, and area under the curve (AUC) analysis for our work.

Results

Sensitivity and negative predictive value of the combined score (ABCD2+CIMT) was the highest (96.3% and 90.9%, respectively), and the specificity and positive predictive value of the CIMT were the highest (57.5% and 63.1%, respectively) to predict cardiovascular events in long-term.

Conclusion

Compared to ABCD2 score, CIMT proved to be more accurate to predict cardiovascular events in long-term follow-ups (AUC = 0.736 vs. AUC = 0.640). However, adding CIMT value to ABCD2 score was even better (AUC = 0.750). Therefore, CIMT measurement in the ABCD2 score after TIA enables prediction of long-term cardiovascular events.

Optimizing the Definitions of Stroke, Transient Ischemic Attack, and Infarction for Research and Application in Clinical Practice

BACKGROUND AND PURPOSE

Until now, stroke and transient ischemic attack (TIA) have been clinically based terms which describe the presence and duration of characteristic neurological deficits attributable to intrinsic disorders of particular arteries supplying the brain, retina, or (sometimes) the spinal cord. Further, infarction has been pathologically defined as death of neural tissue due to reduced blood supply. Recently, it has been proposed we shift to definitions of stroke and TIA determined by neuroimaging results alone and that neuroimaging findings be equated with infarction.

METHODS

We examined the scientific validity and clinical implications of these proposals using the existing published literature and our own experience in research and clinical practice.

RESULTS

We found that the proposals to change to imaging-dominant definitions, as published, are ambiguous and inconsistent. Therefore, they cannot provide the standardization required in research or its application in clinical practice. Further, we found that the proposals are scientifically incorrect because neuroimaging findings do not always correlate with the clinical status or the presence of infarction. In addition, we found that attempts to use the proposals are disrupting research, are otherwise clinically unhelpful and do not solve the problems they were proposed to solve.

CONCLUSION

We advise that the proposals must not be accepted. In particular, we explain why the clinical focus of the definitions of stroke and TIA should be retained with continued sub-classification of these syndromes depending neuroimaging results (with or without other information) and that infarction should remain a pathological term. We outline ways the established clinically based definitions of stroke and TIA, and use of them, may be improved to encourage better patient outcomes in the modern era.

Framingham risk score can predict cognitive decline progression in Alzheimer's disease

The role of vascular factors in influencing cognitive decline has been extensively investigated, and some difficulties in defining their weight in dementia pathogenesis have emerged. The aim of the study was to investigate the relevance of the Framingham cardiovascular risk profile (FCRP) in influencing cognitive deterioration in a population of Alzheimer's disease (AD) patients. Two hundred eighty-four consecutive AD patients were enrolled. For each patient, FCRP score was calculated. We did a 1-year follow-up to quantify the cognitive decline by recording changes in the Clinical Dementia Rating score. The FCRP score predicted cognitive deterioration with an area under the curve of 0.63 (95% confidence interval: 0.57-0.69; p < 0.0001). In the subpopulation of patients with a genetic increased predisposition to develop cognitive deterioration and with an advanced vascular impairment, the FCRP predictive value significantly increased with an area under the curve of 0.77 (95% confidence interval: 0.52-0.93; p < 0.05). Our findings show that FCRP can predict the progression of deterioration in AD patients. This was particularly evident in patients with major genetic and atherosclerotic risk factors.

Improved correlation between carotid and coronary atherosclerosis SYNTAX score using automated ultrasound carotid bulb plaque IMT measurement

Described here is a detailed novel pilot study on whether the SYNTAX (Synergy between percutaneous coronary intervention with TAXUS and cardiac surgery) score, a measure of coronary artery disease complexity, could be better predicted with carotid intima-media thickness (cIMT) measures using automated IMT all along the common carotid and bulb plaque compared with manual IMT determined by sonographers. Three hundred seventy consecutive patients who underwent carotid ultrasound and coronary angiography were analyzed. SYNTAX score was determined from coronary angiograms by two experienced interventional cardiologists. Unlike most methods of cIMT measurement commonly used by sonographers, our method involves a computerized automated cIMT measurement all along the carotid artery that includes the bulb region and the region proximal to the bulb (under the class of AtheroEdge systems from AtheroPoint, Roseville, CA, USA). In this study, the correlation between automated cIMT that includes bulb plaque and SYNTAX score was found to be 0.467 (p < 0.0001), compared with 0.391 (p < 0.0001) for the correlation between the sonographer's IMT reading and SYNTAX score. The correlation between the automated cIMT and the sonographer's IMT was 0.882. When compared against the radiologist's manual tracings, automated cIMT system performance had a lumen-intima error of 0.007818 ± 0.0071 mm, media-adventitia error of 0.0179 ± 0.0125 mm and automated cIMT error of 0.0099 ± 0.00988 mm. The precision of automated cIMT against the manual radiologist's reading was 98.86%. This current automated algorithm revealed a significantly stronger correlation between cIMT and coronary SYNTAX score as compared with the sonographer's cIMT measurements with multiple cardiovascular risk factors. We benchmarked our correlation between the automated cIMT that includes bulb plaque and SYNTAX score against a previously published (Ikeda et al. 2013) AtheroEdgeLink (AtheroPoint) correlation between the automated cIMT that does not include bulb plaque and SYNTAX score and had an improvement of 44.58%. By sampling cIMT in the bulb region, the automated cIMT technique improves the degree of correlation between coronary artery disease lesion complexity and carotid atherosclerosis characteristics.

Sex-associated differences in the modulation of vascular risk in patients with asymptomatic carotid stenosis

In this study, we aimed to identify determinants of the different sex-related stroke risk in subjects with asymptomatic internal carotid artery (ICA) stenosis. In all, 492 women (44.4%) and 617 men (55.6%), with unilateral ⩾ 60% asymptomatic ICA stenosis, were prospectively evaluated with a median follow-up of 37 months (interquartile range, 26 to 43). Vascular risk profile, plaque characteristics, stenosis progression, and common carotid artery intima-media thickness were investigated. Outcome measure was the occurrence of ischemic stroke ipsilateral to ICA stenosis. Myocardial infarction, contralateral stroke and transient ischemic attack were considered as competing events. The incidence rate of ipsilateral stroke over the entire follow-up period was 0.16%: 0.09% (95% confidence interval (CI) 0.05 to 0.15) in women and 0.22% (95% CI 0.17 to 0.29) in men (log-rank test, P<0.001). Stenosis progression significantly influenced the risk of ipsilateral stroke in both men (subhazard ratio, SHR, 8.99) and women (SHR 4.89). Stenosis degree (71% to 90%, SHR 2.35; 91% to 99%, SHR 3.38) and irregular plaque surface (SHR 2.32) were relevant risk factors for ipsilateral stroke only in men. Our findings suggest that characteristics of the stenosis and plaque exert a different effect in modulating vascular risk in the two sexes. Understanding sex differences in cardiovascular disease could help to target sex-specific future therapies.

Impact of kidney function and urinary protein excretion on intima-media thickness in Japanese patients with type 2 diabetes

BACKGROUND

Carotid echo indexes [intima-media thickness (IMT)] are commonly used surrogate markers for cardiovascular disease; however, the impacts of chronic kidney disease (CKD) on changes in IMT are unclear. We examined associations between CKD and IMT in participants with and without type 2 diabetes through longitudinal analysis.

METHODS

In total, 424 subjects were enrolled in this study. IMT was measured as per carotid echo indexes. Relationships between IMT and risk factors were analyzed using multiple linear regression analysis, in which we defined IMT as the dependent variable and atherosclerosis-related factors (age, sex, systolic pressure, total cholesterol, body mass index, estimated glomerular filtration rate (eGFR), uric acid, smoking index, number of antihypertensive drugs, statin use, urinary protein levels, past cardiovascular event, glycated hemoglobin, and diabetes duration) as independent variables.

RESULTS

The study population was composed of 70.3 % male subjects. Participants with diabetes accounted for 64.4 % of the total population. The mean follow-up duration was 2.2 ± 1.5 years. Alterations in IMT tended to be associated with systolic blood pressure (+10 mmHg) (β = -0.0084, p = 0.09) and eGFR (+10 mL/min/1.73 m(2)) (β = -0.0049, p = 0.06) in all participants. In participants without diabetes, alterations in IMT were associated with eGFR (+10 mL/min/1.73 m(2)) (β = -0.0104, p = 0.03) and tended to be associated with systolic blood pressure (+10 mmHg) (β = 0.0094, p = 0.06). No significant relationships were found in participants with diabetes.

CONCLUSION

Low eGFR was associated with progression of carotid thickness independent of common cardiovascular risk factors in non-diabetic participants.

Cortical Ischemic Lesion Burden Measured by DIR Is Related to Carotid Artery Disease Severity

Background: Over time, exposure to cerebrovascular risk factors and carotid artery disease may cause multiple asymptomatic brain cortical and subcortical microinfarcts, which are commonly found at brain autopsy. So far, lack of convenient neuroimaging tools limited the investigation of grey matter ischemic damage in vivo. We applied the Double Inversion Recovery (DIR) sequence to explore the impact of carotid artery disease on intracortical ischemic lesion load in vivo, taking into account the impact of demographic characteristics and vascular risk factors. Methods: DIR was acquired in 62 patients with common cerebrovascular risk factors stratified in three groups according to carotid artery disease severity. Intracortical lesions scored on DIR (DIRlns) were classified by vascular territory, lobe and hemisphere. White matter hyperintensities (WMHs) volume was also quantified on Fluid Attenuated Inversion Recovery sequence (FLAIR). Results: Among demographic characteristics and cerebrovascular risk variables explored, General Linear Model indicated that age and carotid artery disease were significantly associated to DIRlns. After correcting for age, DIRlns load was found to be significantly dependent on carotid artery stenosis severity (F(2, 58) = 5.56, p = 0.006). A linear positive correlation between DIRlns and WMHs was found after correcting for age (p = 0.003). Conclusions: Carotid disease severity is associated with DIRlns accrual. Microembolism and impaired cerebral hemodynamics may act as physiopathological mechanisms underlying cortical ischemic damage. The role of other factors, such as small vessel disease and the possible interaction with carotid disease, remains to be further explored.

Is there an association between asymmetry of carotid artery wall thickness (ACAWT) and cerebrovascular symptoms?

PURPOSE

Previous publications demonstrated that multi-detector-row computed tomography Angiography (MDCTA) can evaluate the carotid artery wall thickness (CAWT). The purpose of this work was to compare the asymmetry of CAWT between carotids in symptomatic and asymptomatic patients.

MATERIAL AND METHODS

Sixty consecutive symptomatic (males 44; median age 64) and 60 asymptomatic sex- and age-matched patients were analysed by using a 40-detector-row CT system. CAWT was calculated for both carotids in each patient and the ratio between the thicker CAWT and the contra-lateral was calculated to obtain the ACAWT index. Bland-Altman, logistic regression and receiver operating characteristic (ROC) curve analysis were calculated.

RESULTS

The Bland-Altman plot demonstrates a very good agreement between measurements with a mean difference value of 3.4% and 95% CI from -8% to 14.8%. The ACAWT was significantly different between symptomatic and asymptomatic patients (with a p value of 0.0001). The ROC area under the curve was 0.742 (p = 0.001). Logistic regression model indicated that ACAWT, CAWT, stenosis degree, and fatty plaques were independent variables associated with cerebrovascular symptoms (p value, respectively, 0.0108, 0.0231, 0.0002, and 0.013).

CONCLUSION

Results of our study indicated that the index of asymmetry in the CAWT might be used as a further parameter to stratify the risk of symptoms related to carotid artery.

Intima Media Thickness Variability (IMTV) and its association with cerebrovascular events: a novel marker of carotid therosclerosis?

PURPOSE

Increased intima-media thickness (IMT) is an early marker of atherosclerotic disease and several prospective studies have demonstrated that IMT is a strong predictor of cerebrovascular complications. In this paper we propose a novel method to assess IMT, called "intima media thickness variability" (IMTV) and evaluate its relationship with the development of cerebrovascular events.

MATERIAL AND METHODS

The study was approved by the local IRB. Twenty consecutive patients underwent ultrasound analysis of the carotid arteries (mean age 68 years; age range 59-81 years). The IMT and IMTV of the 40 carotid vessels was assessed. Bland-Altman statistics were employed to measure the inter-observer variability, and ROC analysis was used to assess the association with cerebrovascular events.

RESULTS

In all cases the ROC area under the curve was higher for IMTV than IMT. There was a statistical significant association between IMTV and cerebrovascular events (P=0.018), but no relationship between IMT and events. The results for inter-observer variability showed a systematic error between 0.04 and 0.08 mm. In the Person Rho correlation analysis in no case a statistical association between IMT and symptoms was detected whereas in 2 cases (observer 1 and observer 2), a statistically significant association between IMTV and symptoms was found.

CONCLUSIONS

Data of this preliminary study suggest that IMTV may represent a powerful method to assess carotid atherosclerotic disease with a significant association to cerebrovascular events.

Clinical determinants of carotid intima-media thickness in patients with diabetes mellitus type 2

BACKGROUND AND PURPOSE

Early atherosclerotic changes in carotid arteries can be detected using ultrasound examination. The aim of this study was to assess correlations between intima-media thickness (IMT) and gender, age and clinical features of diabetes mellitus (DM).

MATERIAL AND METHODS

The study group consisted of 73 patients with type 2 DM (mean age: 63.6 ± 7.5 years), and 74 controls without DM (mean age 62.2 ± 7.5 years). Analysed clinical features of diabetes included disease duration, anti-diabetic treatment, glycaemic control (HbA1c level), presence of metabolic syndrome, and complications of macro- and microangiopathy. IMT was measured using ultrasonography in the carotid arteries (common - CCA, bifurcation, internal - ICA) bilaterally.

RESULTS

Mean and maximum IMT in the CCA was greater in diabetic patients than in controls. Age and male sex, but not vascular risk factors, were independent predictors of increased IMT in all segments. Macroangiopathy correlated with IMT within both CCA in univariate analysis. After adjusting for age and gender, this relationship remained significant in the right CCA in middle-aged patients (59-67 years; p = 0.01 for mean IMT, p = 0.02 for maximum IMT). In patients without metabolic syndrome, IMT in the right CCA bifurcation correlated with HbA1c level (p = 0.05). Patients treated simultaneously with insulin and oral antidiabetic drugs had smaller IMT in the right ICA than those treated with insulin only (0.471 ± 0.105 vs. 0.678 ± 0.209 mm; p = 0.04).

CONCLUSIONS

In diabetic patients, ultrasound IMT measurement can be used to assess the cardiovascular risk and to determine indications for intensified anti-diabetic treatment. IMT is a sensitive marker of early carotid atherosclerosis, particularly on the right side.

Ultrasonographic markers of vascular risk in patients with asymptomatic carotid stenosis

Six-hundred twenty-one subjects with unilateral asymptomatic severe internal carotid artery (ICA) stenosis were prospectively evaluated with a median follow-up of 27 months (min=6, max=68). Vascular risk profile, plaque characteristic, stenosis progression, and common carotid artery intima-media thickness (IMT) were investigated in all patients. Outcome measures were occurrence of ischemic stroke ipsilateral to ICA stenosis and vascular death, while myocardial infarction, contralateral strokes, and transient ischemic attack were considered as competing events. A total of 99 subjects (15.9%) suffered from a vascular event. Among them, 39 were strokes ipsilateral to the stenosis (6.3%). Degree of stenosis, stenosis progression, and common carotid artery IMT resulted as independent predictive factors of ipsilateral stroke. Considering a stenosis of 60% to 70% as reference, a degree between 71% and 90% increased the risk by 2.45, while a degree between 91% and 99% increased the risk by 3.26. The progression of stenosis was a strong risk factor (hazard ratio=4.32). Finally, the role of carotid IMT was confirmed as crucial additional measure, with an increased risk by 25% for each 0.1 mm IMT increase. Our data suggest that IMT, stenosis progression and severity should be considered as risk factors for cerebrovascular events in asymptomatic subjects with severe ICA stenosis.

Enhanced platelet-derived microparticle formation is associated with carotid atherosclerosis in convalescent stroke patients

Platelets participate in the development and progression of atherosclerosis. During this process they interact with endothelial cells and leukocytes. Therefore, we investigated the associations between carotid atherosclerosis and platelet reactivity markers. The platelet surface expression of P-selectin (CD62P) and the activated GPIIb/IIIa receptor (corresponding to increased binding of PAC-1), as well as the fraction of platelet-derived microparticles (PMPs) prior to and after platelet stimulation with TRAP or ADP, were determined using flow cytometry in 94 subjects in the convalescent phase of ischaemic stroke and in 76 disease controls. The mean common carotid intima-media thickness (CCA(mean) IMT), maximal common carotid IMT (CCA(max) IMT) and maximal bifurcation IMT (BIF(max) IMT) were measured bilaterally using B mode, colour Doppler ultrasonography. In stroke subjects IMT within CCA and BIF were greater than in disease controls and the percentage of PMPs prior to and after ex vivo stimulation with agonists was significantly higher than in controls. Multiple regression analysis revealed that PMPs were positively and independently correlated with both CCA(mean) IMT (β = 0.23; p < 0.01) and stroke (β = 0.21; p<0.01), while PAC-1 binding to platelets activated with ADP was negatively and independently associated with CCA(mean) IMT (β = -0.29; p<0.001) and atherosclerotic carotid plaque presence (β = -0.28, p = 0.003). We found a positive association between enhanced PMP formation and atherosclerotic thickening of carotid intima-media or carotid plaque in patients after ischaemic stroke. We demonstrated that diminished expression of active GPIIb/IIIa in the ADP-activated platelets is associated with increased carotid IMT, independently of stroke.

Carotid artery wall thickness measured using CT: inter- and intraobserver agreement analysis

SUMMARY

The purpose of this work was to compare inter- and intraobserver agreement in the analysis of CAWT by using MDCTA. The CAWT in 35 patients was quantified by 4 observers. Bland-Altman statistics were used to measure the agreement between observers. The results of our study demonstrated that the CAWT measured by using MDCTA shows a good reproducibility between observers by considering inter- and intraobserver agreement.

Antiepileptic drugs and markers of vascular risk

OPINION STATEMENT

The most-used treatments for epilepsy worldwide are older-generation drugs such as phenytoin, carbamazepine, phenobarbital, and valproic acid, which have prominent enzymatic effects. Our sense of comfort with these treatments is starting to fade, however, as more and more potential long-term consequences of these drugs come to light. Epidemiologic studies demonstrate that ischemic disease of the heart and brain is more common among patients with epilepsy. Enzyme-inducing drugs are associated with elevations in a host of surrogate markers of vascular risk, suggesting that they could be responsible for increased rates of cardiovascular and cerebrovascular disease. The enzyme-inhibiting drug valproate may have adverse consequences of its own pertaining to glucose and lipid metabolism. These effects stand in addition to those well established in the literature regarding bone metabolism, hormonal abnormalities, and drug-drug interactions. Because patients with epilepsy require medication for years, and often for life, it is difficult to justify the long-term use of these agents when there are capable alternatives. Many of the adverse effects of the older drugs appear to be rapidly reversible, prompting consideration of whether patients who are currently treated with these agents should be switched to alternative therapies, even in the absence of obvious side effects. Newer medications without effects on hepatic enzymes likely do not have these chronic metabolic consequences, and we recommend their use over older-generation drugs whenever possible.

Comparison between manual and automated analysis for the quantification of carotid wall by using sonography. A validation study with CT

PURPOSE

The purpose of this paper was to compare manual and automated analysis for the quantification of carotid wall obtained with sonography by using the computed tomography as validation technique.

MATERIAL AND METHODS

21 consecutive patients underwent MDCTA and ultrasound analysis of carotid arteries (mean age 68 years; age range 59-81 years). The intima-media-thickness (IMT) of the 42 carotids was measured with novel and dedicated automated software analysis (called AtheroEdge™, Biomedical Technologies, Denver, CO, USA) and by four observers that manually calculated the IMT. The carotid artery wall thickness (CAWT) was also quantified in the CT datasets. Bland-Altman statistics was employed to measure the agreement between methods. A Student's t-test was used to test the differences between the IMT values of AtheroEdge™. The study obtained the IRB approval.

RESULTS

The correlation between automated AtheroEdge™ measurements and those of the human experts were equal to 95.5%, 73.5%, 88.9%, and 81.7%. The IMT coefficient of variation of the human experts was equal to 11.9%. By using a Student's t-test, the differences between the IMT values of AtheroEdge™ and those of the human experts were not found statistically significant (p value=0.02). On comparing AtheroEdge™ (using Ultrasound) with CAWT (using CT), the results suggested a very good concordance of 84.96%.

CONCLUSIONS

Data of this preliminary study indicate that automated software AtheroEdge™ can analyze with precision the IMT of carotid arteries and that the concordance with CT is optimal.