Common Carotid Artery Wall Thickness Research Articles

Randomized, placebo-controlled trial of the angiotensin-converting enzyme inhibitor, ramipril, in patients with coronary or other occlusive arterial disease

OBJECTIVESThe primary objective of this study was to investigate the effects of the angiotensin-converting enzyme (ACE) inhibitor, ramipril, on carotid atherosclerosis in patients with coronary, cerebrovascular or peripheral vascular disease.BACKGROUNDAngiotensin-converting enzyme inhibitors have been shown to reduce the risk of coronary events in various patient groups and to prevent the development of atherosclerosis in animal models. It has been hypothesized that the clinical benefits of ACE inhibitors may, therefore, be mediated by effects on atherosclerosis.METHODSSix hundred seventeen patients were randomized in equal proportions to ramipril (5–10 mg daily) or placebo. At baseline, two years and four years, carotid atherosclerosis was assessed by B-mode ultrasound, and left ventricular mass was assessed by M-mode echocardiography.RESULTSBlood pressure (BP) was reduced by a mean of 6 mm Hg systolic and 4 mm Hg diastolic in the ramipril group compared with the placebo group (p < 0.001). There was no difference between groups in the changes in common carotid artery wall thickness (p = 0.58) or in carotid plaque (p = 0.93). Left ventricular mass index decreased by 3.8 g/m2 (4%) in the ramipril group compared with the placebo group (2p = 0.04).CONCLUSIONSThe results provide no support for the hypothesis that reduced atherosclerosis is responsible for the beneficial effects of ACE inhibitors on major coronary events. It is more likely that the benefits are due to lower BP, reduced left ventricular mass or other factors such as reversal of endothelial dysfunction.

Ultrasonographic study of carotid artery structural changes with natural longevity.

The changes in carotid artery structure during the natural longevity of the Uighurs people were compared with other ethnic groups. The 419 subjects were divided into (1) longevity and (2) older groups as follows: Uighurs longevity group in Hotan (ULH); and Uighurs, Hans and Kazaks older groups in Hotan or Balikun (UOH, HOH, HOB and KOB). The wall thickness of the common carotid artery (CCA) was measured by ultrasonography. Risk factors were evaluated by measuring total cholesterol (T-C), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglyceride (TG) and fasting glucose, and by 24-h ambulatory blood pressure monitoring. Wall thickness and blood pressure were greater in the Balikun groups than in the Hotan groups. The CCA wall was thicker in Uighurs and Kazaks than in Hans, in the ULH than in the UOH. There was no significant difference in blood pressure among the Hotan groups. LDL-C and glucose were higher and HDL-C was lower in the Hotan groups than in the Balikun groups. T-C, LDL-C, TG and glucose were higher in the HOH than in the ULH and UOH. Systolic blood pressure and LDL-C were higher and TG was lower in the KOB than in the HOB. These results suggest that an increased CCA wall thickness can be attributed to age in Hotan, and to a higher blood pressure level in Balikun, and that the higher blood pressure affected the Balikun groups more than the Hotan groups.

Association between elevated plasma total homocysteine and increased common carotid artery wall thickness

Homocysteine is increasingly recognized as a risk factor for atherothrombotic arterial diseases. We investigated the relation between plasma concentrations of total homocysteine (tHcy) and common carotid artery intima-media wall thickeness, measured by B-mode ultrasonography, in 513 asymptomatic men and women from eastern Finland aged 45–69 years. The subjects were examined in 1994–95 at the baseline of the Antioxidant Supplementation in Atherosclerosis Prevention (ASAP) study, a randomized double-blind placebo-controlled two by two factorial trial on the effect of vitamin E and C supplementation in the prevention of atherosclerotic progression. The subjects were assigned into two categories according to the plasma tHcy concentration; concentration over 11.5 umol/L (highest quartile) or concentration below 11.5 umol/L. In this study population the mean plasma tHcy concentration was 10.0 μmol/L, and the prevalence of plasma tHcy concentration exceeding 11.5 μmol/L was 33% in men and 18% in women. The adjusted mean intima-media thickness of the right and left common carotid arteries was 1.12 mm in men with elevated plasma tHcy concentration and 1.02 mm in men with a plasma tHcy concentration below 11.5 μmol/L (P = 0.029). In women there was no significant difference. We conclude that elevated plasma tHcy concentrations are associated with early atherosclerosis, as manifested by increased common carotid artery intima-media wall thickeness, in middle-aged eastern Finnish men.

Cardiac and arterial interactions in end-stage renal disease

Although cardiac hypertrophy is a frequent complication of end-stage renal disease (ESRD), relatively little is known about large arterial geometry and function in vivo in these patients, and the relationship between arterial changes and cardiac hypertrophy is unknown. Common carotid artery (CCA) intima-media thickness and internal diameter and left ventricular geometry and function were determined by ultrasound imaging in 70 uncomplicated ESRD patients and in 50 age-, sex-, and blood pressure-matched controls. Arterial distensibility and compliance were determined from simultaneously recorded CCA diameter and stroke changes in diameter and CCA pressure waveforms, obtained by applanation tonometry, and also by the measurement of carotid-femoral pulse wave velocity. Compared with control subjects, ESRD patients had greater left ventricular diameter (P < 0.01), wall thicknesses and mass (P < 0.001), increased CCA diameter (6.25 +/- 0.87 vs. 5.55 +/- 0.65 mm; P < 0.001), larger CCA intima-media thickness (777 +/- 115 vs. 678 +/- 105 microns; P < 0.001) and intima-media cross-sectional area (17.5 +/- 4.5 vs. 13.4 +/- 3.3 mm2; P < 0.001). In uremic patients, arterial hypertrophy was associated with decreased CCA distensibility (17.8 +/- 8.8 vs. 24.0 +/- 12.7 kPa-1.10(-3); P < 0.001) and compliance (5.15 +/- 2 vs. 6.0 +/- 2.5 m2.kPa-1.10(-7); P < 0.05), accelerated carotid-femoral pulse wave velocity (1055 +/- 290 vs. 957 +/- 180 cm/seconds; P < 0.001), early return and increased effect of arterial wave reflections (20.5 +/- 15.4 vs. 9.2 +/- 18.4%; P < 0.001). The latter phenomenons were responsible for increased pulsatile pressure load in CCA (58.3 +/- 21 vs. 48 +/- 17 mm Hg; P < 0.01) and were associated with a decreased subendocardial viability index (157 +/- 31 vs. 173 +/- 30%; P < 0.001). The CCA diameter was correlated with the left ventricular diameter (P < 0.01), and a significant correlations existed between CCA wall thickness or CCA intima-media cross-sectional area and left ventricular wall thicknesses and/or left ventricular mass (P < 0.01). In multivariate analysis, these relationships were independent regarding age, sex, blood pressure and body surface area. The present study documents parallel cardiac and vascular adaptation in ESRD, and demonstrates the potential contribution of structural and functional large artery alterations to the pathogenesis of left ventricular hypertrophy and functional alterations.

Fibrinogen and Factor VIII, but Not Factor VII, Are Associated With Measures of Subclinical Cardiovascular Disease in the Elderly

No studies have examined the associations of coagulation factor levels with measures of subclinical cardiovascular disease (CVD) in the elderly. The Cardiovascular Health Study (CHS) is a prospective, population-based cohort study of CVD in persons older than 65 years. At the baseline examination, we measured fibrinogen, factor VII, and factor VIII levels in 5024 of the 5201 participants of the CHS and examined the associations of these coagulation factors with measures of subclinical CVD in a cross-sectional analysis. Subclinical CVD measures were based on electrocardiography, carotid ultrasonography, echocardiography, and ankle-arm blood pressure measurements (AAI). For analyses, we used the full cohort as well as two mutually exclusive subgroups: those with prevalent clinical CVD at baseline and those without. Fibrinogen and to a lesser extent factor VIII showed positive associations with a variety of subclinical CVD measures. In age-adjusted analyses, fibrinogen and factor VIII were significantly associated with 8 of 10 measures. In multivariate analyses, fibrinogen was significantly associated with carotid artery stenosis, internal (but not common) carotid artery wall thickness, and AAI. Factor VIII was associated with abnormal wall motion and AAI in the full cohort only. Factor VII was not consistently associated with subclinical disease measures. In bivariate analyses that included data from all three groups, there were 5 positive subclinical disease associations and 5 negative associations for factor VII. In multivariate analyses, there were no significant associations between factor VII and subclinical CVD in the full cohort or in either subgroup. We conclude that in these cross-sectional analyses, fibrinogen and to a lesser extent factor VIII are associated with subclinical CVD in the elderly, even in those without symptoms or a history of clinical CVD. Factor VII, however, was not associated with subclinical CVD in the elderly.

Correlates of blood pressure in community-dwelling older adults. The Cardiovascular Health Study. Cardiovascular Health Study (CHS) Collaborative Research Group.

Although elevated blood pressure is an important predictor of cardiovascular disease and stroke in the elderly, little information exists on the distribution and risk factor correlates of blood pressure in this group. As part of the Cardiovascular Health Study, a population-based cohort study of 5201 men and women aged 65 to 101 years, we investigated correlates of systolic and diastolic blood pressure. Multiple regression analyses were conducted for all participants and a subgroup of 2482 without coronary heart disease and not on antihypertensive therapy (the "healthier" subgroup). In the total group, independent predictors of diastolic blood pressure included heart rate, aortic root dimension, creatinine, hematocrit, alcohol use, and black race (positive associations) and internal carotid artery wall thickness, mitral early/late peak flow velocity, white blood cell count, cigarette smoking, and age (negative associations). Positive predictors of systolic blood pressure included mitral late peak flow velocity, left ventricular mass, common carotid artery wall thickness, serum albumin, factor VII, diabetes, alcohol use, and age; negative predictors were coronary heart disease, uric acid, height, and smoking. In the healthier subgroup, positive predictors of diastolic blood pressure included heart rate, hematocrit, serum albumin, creatinine, and body weight, whereas mitral early/late peak flow velocity, serum potassium, smoking, and age inversely related to diastolic pressure. For the same group, common carotid artery wall thickness, left ventricular mass, serum albumin, factor VII, high-density lipoprotein cholesterol, and age were directly related to systolic blood pressure, whereas serum potassium was inversely related. Both systolic and diastolic pressures varied considerably by geographic site.(ABSTRACT TRUNCATED AT 250 WORDS)

Distribution and correlates of sonographically detected carotid artery disease in the Cardiovascular Health Study. The CHS Collaborative Research Group.

This article describes the prevalence of extracranial carotid atherosclerosis assessed by ultrasonography, its association with risk factors, and its relation to symptomatic coronary disease and stroke in men and women aged > or = 65 years. Maximum percent stenosis, maximum common carotid artery wall thickness, and maximum internal carotid artery wall thickness were assessed using duplex ultrasound in 5,201 men and women aged > or = 65 years in the Cardiovascular Health Study, a study of the risk factors and natural history of cardiovascular disease in the elderly. Existing coronary disease and stroke were assessed by physical examination and participant history. Detectable carotid stenosis was present in 75% of men and 62% of women, although the prevalence of > or = 50% stenosis was low, 7% in men and 5% in women. Maximum stenosis and maximum wall thickness measurements increased with age and were uniformly greater at all ages in men than in women (p < 0.00001). Established risk factors for atherosclerosis (hypertension, smoking, diabetes) and indications of vascular disease (left ventricular hypertrophy, major electrocardiographic abnormality, bruits, and history of heart disease or stroke) related to all three carotid artery measures in the elderly. Of the three ultrasound measures, the best correlate for a history of coronary disease was maximum internal carotid artery wall thickness. For stroke the best correlate was common carotid artery wall thickness. Multiple logistic regression models of prevalent coronary heart disease and stroke that included the ultrasound findings indicated, after adjustment for age and sex, that maximum internal wall thickness and maximum common carotid wall thickness were significant correlates of both. Maximum stenosis did not add significantly to the correlation. In the elderly the incidence of carotid atherosclerosis was high, although the frequency of severe disease was low. The prevalence and severity of carotid atherosclerosis continued to increase with age even in the late decades of life, and more disease was found in men than in women at all ages. Known risk factors for atherosclerosis continued to relate to carotid abnormalities in the later decades of life, both in symptomatic and asymptomatic subjects.

Use of monitoring software to improve the measurement of carotid wall thickness by B-mode imaging

High-resolution B-mode imaging is a reliable, easily performed and non-invasive means of studying atherosclerosis in superficial blood vessels. Recently it has been used for in vivo studies on the thickness of the common carotid artery wall. It is very sensitive, although the results of practical investigations are highly dependent on both the operator and the direction and angle of ultrasound beams directed towards the vessel. We have assessed inter- and intra-observer reproducibility of the measurement of common carotid artery wall thickness in 13 subjects, using two procedures. The first was a standard echographical investigation. In the second procedure, the principal parameters recorded from the first investigation were used to reposition the beam with the same incident angle. Intra-observer variability (correlation coefficient, r = 0.61 for procedure 1 and r = 0.77 for procedure 2) and inter-observer variation (r = 0.58 for procedure 1 and r = 0.71 for procedure 2) were reduced when the second investigation was assisted by reproducibility software. The proposed method is a reliable and reproducible way of assessing combined intimal and medial wall thickness in the common carotid artery. It may be possible to improve reproducibility using specific software to aid the operator. Since the intimal and medial thickness of the common carotid artery appears to be a sensitive marker of vascular risk, the proposed standardized method of measuring these parameter may allow early detection and assessment of changes.

Progression and regression of carotid atherosclerosis in clinical trials.

Progression and regression of carotid atherosclerosis in clinical trials 1524-4636 Copyright © 1991 American Heart Association. All rights reserved. Print ISSN: 1079-5642. Online ISSN: 7272 Greenville Avenue, Dallas, TX 72514 Arteriosclerosis, Thrombosis, and Vascular Biology is published by the American Heart Association. 1991, 11:443-451 Arterioscler Thromb Vasc Biol http://atvb.ahajournals.org/content/11/2/443.citation located on the World Wide Web at: The online version of this article, along with updated information and services, is

Ultrasonographic measurement of the common carotid artery wall thickness in hypercholesterolemic patients A new model for the quantitation and follow-up of preclinical atherosclerosis in living human subjects

Ultrasound high resolution B-mode imaging of human arteries allows in vivo an accurate and non-invasive determination of the thickness of the intimal-medial complex. A computer assisted procedure to measure this parameter at the level of common carotid arteries was developed. The average difference between duplicate thickness determinations was 4.6%. The thickness of the intimal medial complex of common carotid arteries was then measured in a group of hypercholesterolemic patients. This parameter was significantly greater in these patients as compared to controls ( P < 0.001). The prevalence of small plaques in the carotid arterial tree was also significantly increased in patients. Analysis of data showed that in controls, but not in patients, the thickness of the intimal medial complex increases with age ( r = 0.46, P < 0.05). Within the hypercholesterolemic group, intimal-medial complex values were greater in male patients and in smokers. It is concluded that the common carotid arteries of hypercholesterolemic patients show thickening of the intimal-medial complex. Cigarette smoking, male sex and age increase the extent of this modification. The determination of this parameter using a non-invasive technique may represent an important tool to monitor in vivo the progression and/or the regression of early atherosclerosis in man.