Common carotid intima-media thickness measurement. A method to improve accuracy and precision (original) (raw)
Related papers
Journal of the American College of Cardiology, 2012
The goal of this study was to compare the performance of several measures of carotid intima-media thickness (C-IMT) as predictors of cardiovascular events (CVEs), and to investigate whether they add to the predictive accuracy of Framingham risk factors (FRFs). Background Various markers of subclinical atherosclerosis have been identified as predictors of CVEs, but the most powerful variable is still under debate. Methods A cohort study was carried out in 5 European countries. A total of 3,703 subjects (median age 64.4 years; 48% men) were followed-up for a median of 36.2 months, and 215 suffered a first CVE (incidence: 19.9/1,000 person-years). Results All measures of C-IMT and the interadventitia common carotid artery diameter (ICCAD) were associated with the risk of CVEs, after adjustment for FRFs and therapies (all p Ͻ 0.005). The average of 8 maximal IMT measurements (IMT mean-max), alone or combined with ICCAD, classified events and non-events better than the common carotid mean IMT (net reclassification improvement [NRI]: ϩ11.6% and ϩ19.9%, respectively; both p Ͻ 0.01). Compared with classification based on FRFs alone, the NRI resulting from the combination of FRFsϩICCADϩIMT mean-max was ϩ12.1% (p Ͻ 0.01). The presence of at least 1 plaque (maximum IMT Ͼ1.5 mm) performed significantly worse than composite IMTs that incorporated plaques (p Ͻ 0.001). Adjusted Kaplan-Meier curves showed that individuals with a FRS ϭ 22.6% (cohort average), and both IMT mean-max and ICCAD above the median, had a 6.5% risk to develop a CVE over 3 years versus a 3.4% risk for those with the same FRS, and both IMT mean-max and ICCAD below the median. Conclusions A risk stratification strategy based on C-IMT and ICCAD as an adjunct to FRFs is a rational approach to prevention of cardiovascular disease.
Prediction of clinical cardiovascular events with carotid intima-media thickness
Circulation, 2007
Background-Carotid intima-media thickness (IMT) is increasingly used as a surrogate marker for atherosclerosis. Its use relies on its ability to predict future clinical cardiovascular end points. We performed a systematic review and meta-analysis of data to examine this association. Methods and Results-Using a prespecified search strategy, we identified 8 relevant studies and compared study design, measurement protocols, and reported data. We identified sources of heterogeneity between studies. The assumption of a linear relationship between IMT and risk was challenged by use of a graphical technique. To obtain a pooled estimate of the relative risk per IMT difference, we performed a meta-analysis based on random effects models. The age-and sex-adjusted overall estimates of the relative risk of myocardial infarction were 1.26 (95% CI, 1.21 to 1.30) per 1-standard deviation common carotid artery IMT difference and 1.15 (95% CI, 1.12 to 1.17) per 0.10-mm common carotid artery IMT difference. The age-and sex-adjusted relative risks of stroke were 1.32 (95% CI, 1.27 to 1.38) per 1-standard deviation common carotid artery IMT difference and 1.18 (95% CI, 1.16 to 1.21) per 0.10-mm common carotid artery IMT difference. Major sources of heterogeneity were age distribution, carotid segment definition, and IMT measurement protocol. The relationship between IMT and risk was nonlinear, but the linear models fitted relatively well for moderate to high IMT values.
Circulation, 1997
Background-It has been argued that lumen diameter of the common carotid artery should be taken into account in analyses on common carotid intima-media thickness (CIMT) and cardiovascular risk. Yet, no published report has dealt with this issue in detail. Methods-In the Rotterdam study baseline ultrasound images of the carotid arteries were made. During follow-up of 8.2 years, 656 new acute myocardial infarctions (AMI) occurred. Regression analysis was used to study myocardial infarction relation to right (or left) common CIMT with various adjustments for right-, or left-sided lumen diameter. Lumen adjustment was made by (1) a simple adjustment in a regression equation;
PloS one, 2018
Carotid intima media thickness (CIMT) predicts cardiovascular (CVD) events, but the predictive value of CIMT change is debated. We assessed the relation between CIMT change and events in individuals at high cardiovascular risk. From 31 cohorts with two CIMT scans (total n = 89070) on average 3.6 years apart and clinical follow-up, subcohorts were drawn: (A) individuals with at least 3 cardiovascular risk factors without previous CVD events, (B) individuals with carotid plaques without previous CVD events, and (C) individuals with previous CVD events. Cox regression models were fit to estimate the hazard ratio (HR) of the combined endpoint (myocardial infarction, stroke or vascular death) per standard deviation (SD) of CIMT change, adjusted for CVD risk factors. These HRs were pooled across studies. In groups A, B and C we observed 3483, 2845 and 1165 endpoint events, respectively. Average common CIMT was 0.79mm (SD 0.16mm), and annual common CIMT change was 0.01mm (SD 0.07mm), both ...
Is Common Carotid Intima Media Thickness an Independent Predictor for Coronary Artery Disease
2010
Introduction: Non-invasive measurement of carotid intima media thickness (IMT) has been noted as a marker for atherosclerosis and can serve as a predictor of cardiovascular events. This study investigates the relationship between carotid IMT and coronary artery disease (CAD). Method: This is a descriptive, analytical cross-sectional study of 300 individuals referring to Isfahan Cardiovascular Research Center (ICRC). Following history taking, clinical examinations, and measurement of body weight and height, the subjects' lipid profile and fasting blood sugar (FBS) were evaluated. The subjects were divided into two groups according to CAD risk factors. The two groups were adjusted based on coronary disease risk factors. Maximum common carotid IMT was measured via B-mode ultrasonography in all subjects. Those with atherosclerotic plaques were excluded from the study. Collected data were statistically analyzed by SPSS 10. Results: 65% of the subjects were male and 35% were female. They had a mean age of 50.72 years. 130 subjects (43%) were placed in the CAD group and 170 (56.7%) in the non-CAD group. There was no significant difference between the two groups in respect of risk factors such as age, total cholesterol, cigarette smoking, body mass index (BMI), hypertension, HDL-C, and LDL-C. Common carotid IMT was evaluated in the two groups. Mean IMT of the CAD group was found to be 0.8 millimeters more than that of the non-CAD group (P<0.05). Discussion: Different studies have shown varying relationships between carotid IMT and CAD. Based on the results of this study and in view of the safety and simplicity of ultrasonographic carotid IMT measurement, IMT can be used as a predictor of atherosclerosis in coronary arteries.
2007
A longitudinal observational study investigated whether the measurement, in clinical practice, of carotid maximum intima-media thickness (Max-IMT) could be combined with the Framingham risk score (FRS) to improve the predictability of cardiovascular events in dyslipidemic patients who are at low or intermediate risk. Max-IMT was measured by ultrasound in 1969 patients attending a lipid clinic. The "best threshold values" (BTVs) above which we considered the Max-IMT to be abnormally high were calculated for our dyslipdemic population for each 10-year age interval in men and women. Two hundred and forty-two patients (age 54 ± 10 years; 43.8% women) with an FRS <20%, i.e. at low or intermediate risk, were monitored for more than 5 years. Twenty-four of these patients suffered a cardiovascular event within 5.1 ± 2.3 years. Both FRS and Max-IMT proved to be independent outcome predictors (p < 0.04, both), with a hazard ratio (HR) of 6.7 (95% CI 1.43, 31.04; p = 0.015) in patients in whom FRS was 10-20% and Max-IMT was above the BTV (60th percentile of Max-IMT distribution for men or 80th for women). In Kaplan-Meier analysis, the Max-IMT significantly improved the predictive value of the FRS (χ 2 = 8.13, p = 0.04). Patients with FRS 10-20% (currently considered intermediate-risk) and also elevated Max-IMT values came into the same high-risk category as patients with FRS 20-30%. The combination of FRS with Max-IMT measurement can be used in routine clinical practice to greatly enhance the predictability of cardiovascular events in the large number of patients who fall into the intermediate-risk category, which currently does not call for aggressive preventive measures.
Chinese medical journal, 2016
Advances in the field of carotid ultrasound have been incremental, resulting in a steady decrease in measurement variability. Improvements in edge detection algorithms point toward increasing automation of CIMT measurements. The major advantage of CIMT is that it is completely noninvasive and can be repeated as often as required. It provides a continuous measure since all subjects have a measurable carotid wall. It is also relatively inexpensive to perform, and the technology is widely available. A graded relation between raising LDL cholesterol and increased CIMT is apparent. Increased CIMT has been shown consistently to relate the atherosclerotic abnormalities elsewhere in the arterial system. Moreover, increased CIMT predicts future vascular events in both populations from Caucasian ancestry and those from Asian ancestry. Furthermore, lipid‑lowering therapy has been shown to affect CIMT progression within 12–18 months in properly designed trials with results congruent with clinic...
American Journal of Hypertension, 2012
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.
BMC Cardiovascular Disorders
Background: The guideline recommendation to not measure carotid intima-media thickness (CIMT) for cardiovascular risk prediction is based on the assessment of just one single carotid segment. We evaluated whether there is a segment-specific association between different measurement locations of CIMT and cardiovascular risk factors. Methods: Subjects from the population-based STAAB cohort study comprising subjects aged 30 to 79 years of the general population from Würzburg, Germany, were investigated. CIMT was measured on the far wall of both sides in three different predefined locations: common carotid artery (CCA), bulb, and internal carotid artery (ICA). Diabetes, dyslipidemia, hypertension, smoking, and obesity were considered as risk factors. In multivariable logistic regression analysis, odds ratios of risk factors per location were estimated for the endpoint of individual age-and sex-adjusted 75th percentile of CIMT. Results: 2492 subjects were included in the analysis. Segment-specific CIMT was highest in the bulb, followed by CCA, and lowest in the ICA. Dyslipidemia, hypertension, and smoking were associated with CIMT, but not diabetes and obesity. We observed no relevant segment-specific association between the three different locations and risk factors, except for a possible interaction between smoking and ICA. Conclusions: As no segment-specific association between cardiovascular risk factors and CIMT became evident, one simple measurement of one location may suffice to assess the cardiovascular risk of an individual.