Common carotid intima-media thickness and arterial stiffness: indicators of cardiovascular risk in high-risk patients. The SMART Study (Second Manifestations of ARTerial disease)

Carotid hemodynamic parameters in hemodialysis patients

BACKGROUND

Atherosclerotic vascular disease is a major cause of morbidity and mortality for patients with end-stage renal disease on maintenance hemodialysis. Early atherosclerotic changes of the arterial wall can be evaluated by intima-media thickness (IMT), presence and structure of plaques and parameters of vascular resistance. The aim of the present study has been to investigate the relationship between carotid IMT and pulsatility index (PI) or resistive index (RI) values in hemodialysis patients.

METHODS

We studied 36 hemodialysis patients (21 female, 15 male; median age 39.5 years, IQR 33.0-54.7 years) and 38 healthy volunteers (20 women, 18 men; median age 41.0 years IQR 32.5-53.5 years). All subjects underwent ultrasonography of common carotid artery, with determination of IMT, PI and RI.

RESULTS

Bilateral and mean carotid IMT were found to be significantly higher in hemodialysis patients than in the control group (P<0.0001). Right and left carotid artery RI values were determined to be lower in hemodialysis patients than in the control group (P=0.007 for both). Similarly, right and left carotid PI values were also determined significantly lower in the hemodialysis group (P=0.005 and P=0.004, respectively). There was a moderate negative correlation between the right carotid IMT and right PI (r=-0.258, P=0.026).

CONCLUSIONS

In contrast to previous studies in patients with diabetes, hypertension or cerebrovascular disease, PI and RI values decrease when IMT increases in hemodialysis patients. This finding may be a result of peripheral vasodilatation secondary to anemia in hemodialysis patients.

Atherosclerosis in patients with biopsy-proven giant cell arteritis

OBJECTIVE

To examine the presence of atherosclerosis in a series of giant cell arteritis (GCA) patients attended to in a community hospital and to determine whether clinical features or steroid therapy might be associated with the development of atherosclerotic disease.

METHODS

Forty consecutive patients diagnosed with biopsy-proven GCA, periodically followed at the rheumatology outpatient clinic of Hospital Xeral-Calde, Lugo (Spain), who had ended steroid therapy and had at least 3 years of followup were assessed for the presence of atherosclerosis by determination of the carotid intima-media thickness (IMT) and carotid plaques using high-resolution B-mode ultrasound. Forty matched controls were also studied.

RESULTS

GCA patients exhibited less carotid artery IMT than did matched controls (mean +/- SD 1.01 +/- 0.16 mm versus 1.13 +/- 0.20 mm; P = 0.005; difference in means 0.12, 95% confidence interval 0.04-0.20). Patients who required steroid therapy for >2 years had greater mean +/- SD carotid IMT (1.04 +/- 0.17 mm versus 0.95 +/- 0.15 mm) but the difference was not statistically significant (P = 0.10). A positive correlation between age at the time of the study and the carotid artery IMT in GCA patients was observed (r = 0.673, P < 0.001). However, adjusting for age, sex, and classic atherosclerosis risk factors, no significant correlation between carotid IMT and the routine laboratory markers of inflammation assessed at the time of disease diagnosis, disease duration, or cumulative prednisone dose was found.

CONCLUSION

The present study demonstrates that atherosclerotic macrovascular disease is not increased in patients with GCA.

Renal and carotid vascular resistance assessed with Doppler sonography

PURPOSE

Resistance index (RI) is widely used for the evaluation of circulatory resistance and atherosclerosis with Doppler sonography, but differences in RI among vascular beds have not been fully elucidated. The present study was designed to evaluate the relationship between renal and carotid artery RI and to compare their relative risk factors for an increase in RI.

METHODS

One hundred eighty-five inpatients who underwent sonographic assessment of the renal and carotid arteries were enrolled in the study.

RESULTS

Multivariate analyses revealed that age, pulse pressure (PP), and serum glucose level were positively correlated, whereas diastolic blood pressure (DBP) and creatinine clearance were negatively correlated with the RI of the interlobar arteries. Sex (male) and PP correlated positively, whereas DBP correlated negatively with the RI of the common carotid artery (CCA). The RI of the interlobar arteries was positively associated with that of the CCA, even after adjustment for major cardiovascular risk factors.

CONCLUSIONS

These findings suggest that RI of the renal and carotid arteries increase in parallel to a certain extent. On the other hand, risk factors for the increase of RI of the carotid and renal arteries differed in part, suggesting that specific control of respective risk factors may also be needed to prevent vascular damage in each vascular bed.

Toll-like receptor 4 gene (Asp299Gly) polymorphism associates with carotid artery elasticity. The cardiovascular risk in young Finns study

OBJECTIVE

Early subclinical markers of atherosclerosis, such as carotid artery intima media thickness (IMT) and elasticity predict future coronary events. The G allele of the Toll-like receptor 4 (TLR-4) gene Asp299Gly polymorphism has been previously associated with decreased development of atherosclerosis and with lower risk of myocardial infractions. We wanted to examine the association of this polymorphism with carotid IMT and compliance in a population of young Finnish Caucasian adults.

METHODS

Carotid artery IMT and elasticity indices of 2201 study subjects who participated in a randomized multicenter study (cardiovascular risk in young Finns study) were measured with ultrasound. The genotyping was performed using the TaqMan 5'-nuclease assay.

RESULTS

According to multivariate linear regression analysis adjusted with potential confounders, the G allele carriers had significantly higher carotid arterial compliance, measured in increase of luminal diameter percentage in response to blood pressure rise of 10 mmHg, than did the AA homozygotes (beta=0.099 with 95% CI 0.029-0.169 and p=0.006). The difference between AA homozygotes and GG homozygotes was even more pronounced (beta=0.382 with 95% CI 0.119-0.644 and p=0.004). Variation in the TLR-4 genotype was not related with IMT. The results of the two independent study cohorts of Eastern and Western Finland were in accordance with the results of the whole combined study population.

CONCLUSION

The G allele of the TLR-4 gene Asp299Gly polymorphism is associated with increased carotid artery compliance in young adults. This beneficial effect of the G allele may reduce the risk of future cardiovascular events.

High prevalence of subclinical atherosclerosis in psoriatic arthritis patients without clinically evident cardiovascular disease or classic atherosclerosis risk factors

OBJECTIVE

To assess the presence of subclinical atherosclerosis in patients with psoriatic arthritis (PsA) without clinically evident atherosclerosis or its complications, and to assess whether demographic or clinical factors affect the development of atherosclerotic disease in a series of patients with PsA attended to in a community hospital.

METHODS

Fifty-nine patients with PsA who fulfilled the Moll and Wright criteria were recruited from Hospital Xeral-Calde (Lugo, Spain). Patients seen during the period of recruitment who had classic cardiovascular risk factors or had experienced cardiovascular or cerebrovascular events were excluded. Fifty-nine healthy matched controls were also studied. Carotid artery intima-media thickness (IMT) and carotid plaques were measured in the right common carotid artery. The study was performed using high-resolution B-mode ultrasound.

RESULTS

Patients with PsA exhibited greater carotid artery IMT than did matched controls (mean +/- SD 0.699 +/- 0.165 mm versus 0.643 +/- 0.111 mm; P = 0.031; difference of means 0.056; 95% confidence interval 0.005-0.108). Adjusted for age, the carotid IMT was correlated with age at the time of PsA diagnosis (partial correlation coefficient [r] = -0.264, P = 0.04), disease duration (r = 0.264, P = 0.04), total cholesterol (r = 0.233, P = 0.01), and low-density lipoprotein cholesterol (r = 0.243, P = 0.01).

CONCLUSION

The present study demonstrates that patients with PsA without cardiovascular risk factors or clinically evident cardiovascular disease have a high prevalence of macrovascular disease in the form of increased carotid artery IMT compared with ethnically matched controls.

Carotid artery distensibility: a reliability study

OBJECTIVE

Carotid distensibility (CD) is a measure of carotid artery elasticity that has been introduced as a risk factor for cardiovascular disease. Information regarding reproducibility of sonographic CD measures is limited. The objective of this study was to evaluate the inter-reader reliability of sonographic measurements of common carotid artery (CCA) diameters and derived metrics of CD.

METHODS

Two independent readers (R1 and R2) measured the systolic diameter (SD) and diastolic diameter (DD) for the right CCA from the B/M-mode sonographic registrations among 118 subjects. The derived CD metrics (strain, elastic modulus [E], stiffness [beta], and CD) were calculated. The inter-reader type 3 intraclass correlation coefficients (ICC3,1) for carotid diameters were calculated.

RESULTS

The mean SDs +/- standard deviation were 7.15 +/- 1.43 mm for R1 and 7.24 +/- 1.43 mm for R2. The mean DDs were 6.71 +/- 1.36 mm for R1 and 6.68 +/- 1.41 mm for R2. The mean differences of SD and DD between R1 and R2 were 0.08 +/- 0.40 mm (paired t test, P = .04) and 0.03 +/- 0.43 mm (paired t test, P = .46), respectively. Inter-reader type 3 intraclass correlation coefficients were 0.96 for SD and 0.95 for DD. We observed a significant association of demographics with carotid diameters but not with derived CD metrics or risk factors.

CONCLUSIONS

Our results suggest good reproducibility of CCA diameters measured with B/M-mode sonography. However, very small changes in linear measurements of carotid diameters can have big effects on estimates of arterial mechanical properties such as strain and Young's modulus. The standard boundary identification methods may not be precise and reproducible enough for use in a clinical setting.

The mechanical performance and histomorphological structure of the descending aorta in hyperthyroidism

Thyroid hormones decrease systemic vascular resistance by directly affecting vascular smooth muscle relaxation. There is limited literature about their effect on the mechanical performance of the aortic wall. Therefore, the authors determined the influence of hyperthyroidism on the mechanical properties and histomorphological structure of the descending thoracic aorta in rats. Severe hyperthyroidism was induced in 20 male Wistar rats by administering L-thyroxine (T(4)) in their drinking water for 8 weeks; age-matched normal euthyroid rats acted as controls. Animals were sacrificed, and the mechanical and histomorphometrical characteristics of the descending thoracic aorta were studied. The aortic wall of hyperthyroid rats was stiffer than that of euthyroid animals at the upper physiologic levels of stress or strain (p < 0.05) but less stiff at the lower physiologic and lower levels (p < 0.05). The aorta of hyperthyroid animals compared with that of euthyroid ones showed an increase of the internal and external diameters (p < 0.05), the media area (p < 0.05), the number of smooth muscle cell nuclei (p < 0.05), and the collagen density (p < 0.05) and a decrease in the elastin laminae thickness (p < 0.001) and elastin density (p < 0.001). In hyperthyroid rats, the aortic wall was stiffer at the upper physiologic and higher levels of stress and strain. These changes correlated with microstructural changes of the aortic wall. The coexistence of hyperthyroidism with disease states or clinical conditions that predispose to increased arterial pressure may be associated with increased arterial stiffness and have undesirable consequences on the mechanical performance of the thoracic aorta and hemodynamic homeostasis. These changes could lead to an increased risk for developing vascular complications.

Endothelial dysfunction, intima-media thickness, ankle-brachial pressure index, and pulse pressure in young post-myocardial infarction patients with various expressions of classical risk factors

Coronary risk assessment based on the presence of classical risk factors may be insufficient. Several markers of arterial function and morphology, such as endothelial dysfunction (ED), intima-media thickness (IMT), ankle-brachial pressure index (ABPI), and pulse pressure (PP) may be useful in coronary risk estimation. To investigate their usefulness, we compared them in young post-myocardial infarction (MI) patients with various expressions of classical risk factors. Young male patients (on average 44 years old) in the stable phase after MI were included in the study. Twenty patients had high and 21 patients low expression of risk factors, while 25 healthy age-matched males served as controls. Endothelial dysfunction (estimated by ultrasound measurement of the flow-mediated dilation [FMD] of the brachial artery), IMT (of common carotid arteries), ABPI, and PP were compared between both groups of patients and controls. Compared with the control group, endothelial function and IMT were significantly impaired in both groups of patients, whereas ABPI was significantly reduced only in high-risk patients, and PP was similar in patients and controls. In all subjects, the level of FMD was significantly negatively related to IMT (r = -0.38, P = 0.01). Our study showed that endothelial function and IMT (but not ABPI and PP) are impaired in young post-MI patients independently of presence or absence of classical risk factors. Thus, we conclude that in young patients ED and IMT better assess coronary disease than classical risk factors, and are probably better markers of coronary risk.

Predictive Value of Associations Between Carotid Arterial Sclerosis and Left Ventricular Diastolic Dysfunction in Patients with Cardiovascular Risk Factors

It is well known that arterial stiffness affects the morbidity and mortality associated with cardiovascular disease. However, there are limited data addressing the relationship between arterial stiffness and left ventricular (LV) diastolic function in patients with cardiovascular risk factors. Subclinical atherosclerosis was determined by measuring the intima-media thickness and stiffness (beta) of the left and right common carotid arteries using B- and M-mode ultrasonography in 30 patients with one or more cardiovascular risk factors. LV systolic and diastolic function were also determined by measuring transmitral flow velocity, mitral annular motion velocity, and myocardial strain and strain rate profiles using pulsed Doppler, tissue velocity, and ultrasonic strain imaging. The carotid stiffness beta was greater and the peak early diastolic strain rates of the LV posterior and inferior walls were lower in these patients than in the age-matched control group. The carotid intima-media thickness correlated only with body mass index and LV wall thickness. The carotid stiffness beta correlated with age, peak early diastolic velocity and deceleration time of the transmitral flow, peak early diastolic mitral annular motion velocity, and peak early diastolic strain rates of the LV walls. Multiple linear regression analysis revealed that early diastolic strain rates of the LV walls are strongly related to carotid stiffness beta. In conclusion, LV relaxation is significantly associated with carotid arterial atherosclerosis, particularly sclerosis, in patients with cardiovascular risk factors. These results support the importance of screening using ultrasonic strain imaging and early intervention in this patient population.

Intima-media thickness and arterial stiffness of carotid artery in Korean patients with Behçet's disease

Behçet's disease (BD) is a systemic vasculitis involving diverse sizes of arteries and veins. We performed this study to evaluate the vascular changes by assessment of the arterial stiffness and intima-media thickness (IMT) of carotid artery in Korean patients with BD. Forty-one patients with BD and age-, and sex-matched 53 healthy subjects were recruited in this study. Carotid arterial stiffness and IMT were assessed by using high-resolution B-mode ultrasonography. Arterial stiffness parameters such as carotid arterial distensibility coefficient, stiffness index, and incremental elastic modulus (E(inc)) were significantly increased in BD patients compared with those in healthy subjects, but not in IMT. Positive relationship was noted between age and IMT, whereas age of onset was significantly associated with arterial stiffness in BD. This finding suggests impaired endothelial function before visible structural changes of arterial wall in BD. Age and age of onset may be an independent risk factor for carotid IMT and arterial stiffness, respectively. Further studies in more large populations are required to confirm our results.

Risk for transient ischemic attacks is mainly determined by intima-media thickness and carotid plaque echogenicity

BACKGROUND

Stenosis severity, plaque morphology, and intima-media thickness (IMT), all have been found to provide prognostic information in patients with asymptomatic carotid artery disease. However, limited data exist on the association between these parameters and the risk for transient ischemic attack (TIA).

METHODS

We compared the ultrasonographic characteristics of 88 consecutive patients with first TIA without known cardioembolic source with those of 176 propensity-matched asymptomatic control subjects.

RESULTS

IMT was higher in TIA patients compared to control subjects (0.74+/-0.14 mm versus 0.68+/-0.13 mm, p=0.001). Plaques were found in 70.5% of patients and 64.8% of controls (p=0.407). Compared with controls, TIA patients demonstrated more frequently predominantly echolucent lesions (77.4% versus 56.1%, p=0.005) and high-grade carotid stenoses (21.0% versus 9.6%, p=0.042). TIA patients with low-to-moderate grade (<70%) lesions exhibited higher IMT and more prevalent echolucent morphology in comparison with their control counterparts. No significant differences were observed between groups regarding high-grade lesions. In multivariate models, IMT and plaque echogenicity, but not stenosis severity, emerged as independent determinants of risk.

CONCLUSIONS

Risk for TIA is primarily associated with IMT and plaque echogenicity, especially in the absence of high-grade lesions. Stenosis severity appears to be of limited prognostic value.

Arterial stiffness as a risk factor for coronary atherosclerosis

The major pathophysiologic process of coronary atherosclerosis is a defect or injury of the arterial endothelial function. The rate of progression of coronary atherosclerosis is highly variable and mainly determined by risk contributors such as lipids, glucose, and smoking. Coronary plaque rupture is the precipitating factor for clot formation and acute coronary events. Measurement of arterial stiffness with different noninvasive techniques provides information about the functional and structural vascular changes at the level of the aorta, muscular conduit arteries, the peripheral branches, and the microvascular components. Arterial stiffness has been related to the Framingham and other cardiovascular risk scores. Large artery stiffness contributes to exercise-induced myocardial ischemia in patients with coronary artery disease. It can predict the outcome after coronary interventions. There is now evidence that arterial stiffness is a predictor for cardiovascular events in the general population, in patients with hypertension, end-stage renal disease, impaired glucose intolerance, and coronary artery disease. Future studies are warranted to demonstrate the value of follow-up of arterial stiffness as a marker of reduction of arterial wall damage during antihypertensive, antidiabetic, and lipid-lowering therapy. Promising study results show that measurement of arterial stiffness could become an important part of the routine assessment of patients in daily practice.

Uric acid level and its association with carotid intima-media thickness in patients with hypertension

OBJECTIVE

Carotid intima-media thickness (C-IMT) measured noninvasively by ultrasonography is now widely used as a surrogate marker for atherosclerotic disease and directly associated with increased risk of cardiovascular disease. Hyperuricemia (HU) is a well recognized risk factor for cardiovascular diseases. The independence of this association from other confounding factors has remained controversial. But the possible contributory effect of HU to carotid intima-media thickness (C-IMT) produced by hypertension (HT) has not been clarified yet. The study was designed to assess the C-IMT in patients with hypertension (HT) with or without HU.

METHODS

The study participants consisted of 30 patients (men 60%, mean age+/-S.D.: 49+/-11 years) with HT without HU, and 25 patients with HT and HU (men 52%, mean age+/-S.D.: 52+/-12 years), and 25 age-matched healthy control subjects (men 56%, mean age+/-S.D.: 50+/-13 years). All study groups were examined by B-mode ultrasound to measure the C-IMT at the far wall of the common carotid artery.

RESULTS

C-IMT were significantly higher in the patient groups (HT without HU and HT with HU) compared to the control cases (0.70+/-0.14, 0.83+/-0.16 versus 0.57+/-0.16, mm, respectively, p<0.001). In the patients groups, patients with HU had significantly higher carotid IMT compared to the patients without HU. In stepwise linear regression analysis, we found that serum uric acid (SUA) levels independently but modestly associated with C-IMT (beta=0.42, p=0.002).

CONCLUSION

We have shown that higher SUA levels are associated with atherogenesis independent from hypertension. Prospective studies will be necessary to confirm and extend these findings including early screening for hyperuricemia and lowering of SUA level looking at potential benefits in slowing progression of C-IMT in hypertensive patients.

Carotid arterial stiffness is marginally higher in the metabolic syndrome and markedly higher in type 2 diabetes mellitus in patients with manifestations of arterial disease

INTRODUCTION

Insulin resistance is generally considered to be of major importance in the pathophysiology of the metabolic syndrome and type 2 diabetes mellitus, both high-risk conditions for cardiovascular complications. Carotid artery stiffness is increasingly recognized as an important predictor of cardiovascular morbidity and mortality. Therefore, in the present study we determined whether the metabolic syndrome (MetSyn) and type 2 diabetes mellitus (DM2) are associated with carotid artery stiffness in patients with already clinical manifestations of arterial disease.

METHODS AND RESULTS

A cross-sectional study in 2105 patients with manifest arterial disease (cerebral, coronary or peripheral artery disease, renal artery stenosis or an aneurysm of the abdominal aorta) was performed. The difference in carotid stiffness between patients with and without MetSyn and with and without DM2 was studied with linear regression analysis. Compared to patients without DM2 (N=1112), patients with DM2 (N=301) had significantly higher arterial stiffness (distension -18.5 (-35.1;-1.9) 95% CI/distensibility -1.8 (-2.2;-1.4) 95% CI). Generally, there was a trend of higher carotid stiffness in patients with MetSyn (N=922) compared to patients without (N=1112) MetSyn (distension -9.6 (-21.5;2.3) 95% CI/distensibility -2.0 (-2.6;-1.4) 95% CI). Excluding the patients with also DM2 (N=230) from the MetSyn-group diminished this relation (distension -5.7 (-18.8;7.4) 95% CI/distensibility -1.1 (-1.6;-0.6) 95% CI). Furthermore, in the population as a whole, carotid artery stiffness increased with increasing number of components of the metabolic syndrome (p=0.08 for distension/p< or =0.001 for distensibility). In addition, this association was not as clear after exclusion of the patients with DM2 from the MetSyn-group (p=0.24 for distension/p<0.001 for distensibility). From all the components of the MetSyn only high blood pressure and high fasting glucose influenced the carotid artery stiffness.

CONCLUSIONS

We concluded that (increasing number of components of) the metabolic syndrome were associated with marginally higher carotid artery stiffness, while type 2 diabetes was associated with a marked increase in carotid artery stiffness, in patients with already clinical manifestations of arterial disease.

Association of arginase 1 gene polymorphisms with the risk of myocardial infarction and common carotid intima media thickness

BACKGROUND

Recently, it was suggested that arginase (ARG)1 plays an important role in atherogenesis. However, because of its complex functions depending on vascular cell type, its impact on atherogenesis remains unclear.

OBJECTIVE

To evaluate the association between ARG1 polymorphisms and phenotypes related to atherosclerosis.

METHODS

Among 10 ARG1 polymorphisms selected from databases, 4 single-nucleotide polymorphisms (rs2781666; rs2781667; rs2781668; rs17599586) were tested for association with myocardial infarction (MI) in a case-control study (350 cases vs 581 controls), and with common carotid artery (CCA) intima-media thickness (CCA-IMT) in an independent sample of 963 subjects (Etude du Vieillissement Artériel (EVA) study).

RESULTS

The genotype distribution of the rs2781666 G/T polymorphism differed significantly between MI cases and controls (p = 0.005), and the risk of MI was consistently increased for both GT heterozygotes (OR (95% CI) 1.5 (1.1 to 2.0)) and TT homozygotes (OR (95% CI) 2.2 (1.1 to 4.4)). In the EVA study, the rs2781666 polymorphism was also associated with an increase in CCA-IMT (p = 0.010), a surrogate marker of MI.

CONCLUSIONS

The ARG1 rs2781666 polymorphism was consistently associated with MI and an increased CCA-IMT. These findings reinforce the hypothesis of a significant role of ARG1 in vascular pathophysiology.

Effects of alendronate sodium therapy on carotid intima media thickness in postmenopausal women with osteoporosis

Osteoporosis and cardiovascular disease are major health problems that lead to morbidity and mortality. Bisphosphonates are among the drugs used most frequently worldwide to treat osteoporosis, especially in older women. B-mode ultrasonography has recently become a valuable tool for early diagnosis of atherosclerotic disease because of its ability to measure carotid artery intima media thickness (CIMT). The purpose of the present study was to investigate whether alendronate sodium therapy has an effect on CIMT in postmenopausal women with osteoporosis. A total of 71 postmenopausal women with osteoporosis were evaluated before and after they began taking alendronate sodium; follow-up was provided for an average of 13+/-2 mo. Osteoporosis was diagnosed with the use of dual-energy x-ray absorptiometry, and therapy with alendronate sodium was begun at a dose of 70 mg/wk. For CIMT, B-mode ultrasonography was performed on the right and left middle and distal main carotid arteries. Before alendronate sodium therapy was initiated, the average CIMT value was 0.734+/-0.121 mm; after therapy, the average CIMT was 0.712+/-0.111 mm. This difference was not confirmed to be statistically significant. Treatment of osteoporosis does not seem to have an effect on CIMT, which is an early marker of atherosclerosis.

What is the role of angiotensin-receptor blockade in cardiovascular protection?

The role of angiotensin II, the key mediator of the renin-angiotensin-aldosterone system, in the pathophysiology of cardiovascular disease is well known. Pharmacologic interruption of the activity of angiotensin II, either through blockade of the angiotensin receptor or inhibition of angiotensin-converting enzyme, is associated with a reduction in cardiovascular disease morbidity and mortality, as evidenced by accumulated data from large-scale, well-controlled clinical trials in high-risk populations. As the underlying mechanisms of vascular disease and the effects of blockade of the renin-angiotensin-aldosterone system on these processes have been further defined, the therapeutic focus has begun to shift toward prevention of disease progression at earlier stages. Continued research has identified early signs of vascular disease, such as endothelial dysfunction and vascular and cardiac remodeling, which occur long before clinical manifestations of cardiovascular disease become evident. Diagnostic tests are now available to assess otherwise healthy individuals for these signs. A preliminary trial is under way to evaluate the role of angiotensin receptor blockade as preventive treatment of individuals with early signs of vascular or cardiac disease.

Risk factors for cystoid macular oedema in patients with uveitis

PURPOSE

To determine ophthalmologic and systemic factors associated with the presence of cystoid macular oedema (CMO) in patients with uveitis.

METHODS

Retrospective cross-sectional study in which 97 consecutive patients with uveitis filled in an extensive questionnaire for the presence of cardiovascular diseases and its risk factors. An analysis of the ophthalmologic and questionnaire data was conducted.

RESULTS

CMO was present in 44% (43/97) of patients. Its presence was strongly associated with increasing age (P=0.001) and age at onset of uveitis (P<0.001). For patients older than 50 years, the risk of having CMO was 3.8-fold (95% confidence intervals 1.6-9.0) larger than for younger patients. The most frequent anatomic location of uveitis associated with CMO was panuveitis (49%). Papillary leakage on fluorescein angiography was associated with CMO (P<0.001), independently of other risk factors. After adjustment for age, multivariate logistic regression showed no association between cardiovascular disease and its risk factors and the presence of CMO.

CONCLUSIONS

Age, independent of duration of uveitis, was a major risk factor for the presence of CMO in uveitis. A positive correlation between CMO and papillary leakage on angiography was noted.

MRI of atherosclerosis in clinical trials

Magnetic resonance imaging (MRI) of the arterial wall has emerged as a viable technology for characterizing atherosclerotic lesions in vivo, especially within carotid arteries and other large vessels. This capability has facilitated the use of carotid MRI in clinical trials to evaluate therapeutic effects on atherosclerotic lesions themselves. MRI is specifically able to characterize three important aspects of the lesion: size, composition and biological activity. Lesion size, expressed as a total wall volume, may be more sensitive than maximal vessel narrowing (stenosis) as a measure of therapeutic effects, as it reflects changes along the entire length of the lesion and accounts for vessel remodeling. Lesion composition (e.g. lipid, fibrous and calcified content) may reflect therapeutic effects that do not alter lesion size or stenosis, but cause a transition from a vulnerable plaque composition to a more stable one. Biological activity, most notably inflammation, is an emerging target for imaging that is thought to destabilize plaque and which may be a systemic marker of vulnerability. The ability of MRI to characterize each of these features in carotid atherosclerotic lesions gives it the potential, under certain circumstances, to replace traditional trials involving large numbers of subjects and hard end-points--heart attacks and strokes--with smaller, shorter trials involving imaging end-points. In this review, the state of the art in MRI of atherosclerosis is presented in terms of hardware, image acquisition protocols and post-processing. Also, the results of validation studies for measuring lesion size, composition and inflammation will be summarized. Finally, the status of several clinical trials involving MRI of atherosclerosis will be reviewed.

Similitudes y diferencias entre los pacientes con aterosclerosis sintomática de distintos territorios. Cohorte AIRVAG (Atención Integral al Riesgo VAscular Global)

BACKGROUND AND OBJECTIVE

Even though atherosclerosis is a systemic disease, few prospective studies have evaluated in a thorough and systematic manner the whole vascular tree in patients with clinical damage of different territories.

PATIENTS AND METHOD

Prospective protocolized study of 269 consecutive patients younger than 70, attended because of symptomatic arteriosclerosis of any territory -53% coronary (CHD), 32% cerebrovascular (CVD), 15% peripheral (PVD)-. Patients underwent evaluation of risk factors and their control, systematic non-invasive study of the vascular tree (Doppler-ultrasound) and comparison between groups according to the index territory.

RESULTS

Even though all risk factors were represented in the 3 groups, male sex, smoking and diabetes were more frequent in PVD and dyslipemia was more common in CHD (p < 0.05) Abdominal aortic diameter and carotid intima-media thickness were similar for all groups, while the number of carotid plaques was higher in PVD. CHD patients more often presented left ventricular hypertrophy and reduced ejection fraction. PVD patients showed a marked reduction of the ankle-brachial index as well as increased C-reactive protein and homocysteine (p < 0.05). Severe unsuspected vascular lesions were found in 13% of cases (95% confidence interval, 9.5-17.6%). Risk factor control was better for CHD, followed by CVD and PVD, but was globally poor.

CONCLUSIONS

The systematic evaluation of the vascular tree detects generalized atherosclerotic lesions, in some cases severe and clinically unsuspected. New markers to identify patients at very high risk are necessary. Peripheral vascular disease identifies a group of patients of particular risk. Risk factor control is deficient, particularly among PVD patients.

Extent of atherosclerosis and prognosis of patients with aneurysmal subarachnoid haemorrhage

BACKGROUND AND PURPOSE

Atherosclerosis impairs the endothelial dependent vasodilatation and may change the diameter and plasticity of cerebral vessels. The aim of this study was to investigate if an index of the occurrence of atherosclerosis is associated with the risk of delayed cerebral ischemia or poor outcome after subarachnoid haemorrhage.

METHODS

To assess the likelihood of atherosclerosis we used a modified version of the Framingham Heart Study Coronary Heart Disease Prediction Chart. The relation of this index to the occurrence of delayed cerebral ischemia was studied by means of survival analysis and to poor outcome by regression analysis. A multivariate analysis was used to investigate the independent contribution of the atherosclerosis index.

RESULTS

Three hundred and twenty three patients were retrieved from our database from the period 1997 to 2004. The index of atherosclerosis related to a good clinical condition on admission (p = 0.01). A high risk of atherosclerosis independently predicted poor outcome (OR 4.3; 95%CI 1.6-12). This was not caused by an increase in the occurrence of delayed cerebral ischemia (HR 1.1; 95%CI 0.6-2.1), but, in part, by a marked decrease in recurrent bleeding in patients with no or minor atherosclerosis.

CONCLUSIONS

An index of the occurrence of atherosclerosis is related to prognosis after subarachnoid haemorrhage. The use of the score may focus attention on patients at risk for poor outcome after subarachnoid haemorrhage.

Accelerated atherosclerosis in pre-menopausal female patients with rheumatoid arthritis

Increased mortality due to cardiovascular disease in rheumatoid arthritis (RA) patients was reported. Using B-mode ultrasonography we compared intima-media thickness (IMT) and plaque occurrence (indicators of asymptomatic atherosclerosis) in the carotid arteries in 70 pre-menopausal, female RA patients and 40 controls. Correlations with different risk factors were evaluated. The IMT values were higher in RA patients (0.59 mm vs. 0.47 mm, P < 0.0001) and they had more plaques (P = 0.023). In RA patients higher levels of sensitive CRP (P < 0.0001), ICAM (P < 0.0001), VCAM (P < 0.0001), IL-2 (P < 0.001), IL-6 (P = 0.009) and TNF-alfa (P < 0.01) were found. A correlation between IMT and triglycerides (P = 0.018) and a negative correlation between IMT and HDL cholesterol (P = 0.037) were found. With multiple regression analysis the association between IMT and sensitive CRP (P = 0.027) and presence of plaques and apolipoprotein B (P = 0.028) was established. The results indicate that even pre-menopausal, female RA patients had accelerated atherosclerosis. Chronic systemic inflammation may play an important role in atherogenesis.

Common carotid arterial stiffness and the risk of ischaemic stroke

In the present case-control study we aimed to investigate the association of common carotid arterial (CCA) stiffness with ischaemic stroke (IS) and to determine whether this relationship was independent of conventional risk factors including CCA intima-media thickness (CCA-IMT). CCA distensibility, defined as the change of CCA-diameter during the cardiac cycle, and CCA-IMT were evaluated by means of high-resolution B-mode carotid ultrasound examination in consecutive, first-ever IS patients (n=193) and in age- and sex-matched control subjects (n=106). The CCA distensibility (inverse of CCA stiffness) was significantly (P=0.007) lower in IS (0.353 mm, 95% CI: 0.326-0.379) than in control subjects (0.415 mm, 95% CI: 0.378-0.451) even after adjusting for blood pressure values, diastolic CCA-diameter and height. The multivariate logistic regression procedure selected CCA-IMT and CCA distensibility as the only independent predictor variables of IS. Each 1 SD increase in the CCA-IMT and each 1 SD decrease in the CCA distensibility independently increased the likelihood of IS by 167.0% (OR: 2.67, 95% CI: 1.80-3.96, P<0.001) and 59.0% (OR: 1.59, 95% CI: 1.22-2.07, P=0.001) respectively. Increased CCA stiffness is associated with IS independent of conventional risk factors and CCA-IMT. The causal interrelationship between the elastic properties of the CCA and the risk of stroke deserves further investigation by longitudinal studies.

Association between carotid hemodynamics and asymptomatic white and gray matter lesions in patients with essential hypertension

The aim of this study was to clarify the magnitude of common carotid artery (CCA) structural and hemodynamic parameters on brain white and gray matter lesions in patients with essential hypertension (EHT). The study subjects were 49 EHT patients without a history of previous myocardial infarction, atrial fibrillation, diabetes mellitus, impaired glucose tolerance, chronic renal failure, symptomatic cerebrovascular events, or asymptomatic carotid artery stenosis. All patients underwent brain MRI and ultrasound imaging of the CCA. MRI findings were evaluated by periventricular hyperintensity (PVH), deep and subcortical white matter hyperintensity (DSWMH), and état criblé according to the Japanese Brain dock Guidelines of 2003. Intima media thickness (IMT), and mean diastolic (Vd) and systolic (Vs) velocities were evaluated by carotid ultrasound. The Vd/Vs ratio was further calculated as a relative diastolic flow velocity. The mean IMT and max IMT were positively associated with PVH, DSWMH, and état criblé (mean IMT: rho=0.473, 0.465, 0.494, p=0.0007, 0.0014, 0.0008, respectively; max IMT: rho=0.558, 0.443, 0.514, p=0.0001, 0.0024, 0.0004, respectively). Vd/Vs was negatively associated with état criblé (rho=-0.418, p=0.0038). Carotid structure and hemodynamics are potentially related to asymptomatic lesions in the cerebrum, and might be predictors of future cerebral vascular events in patients with EHT.

Plasma levels of adiponectin and soluble thrombomodulin in hypothyroid patients with normal thyroid function following levothyroxine replacement therapy

Hypothyroidism is associated with increased morbidity from cardiovascular disease, and adiponectin (ApN) is a newly-identified adipocytokine, which is expressed in human adipose cells and may have a protective effect against the development of coronary artery disease. The aim of the study was to evaluate the involvement of ApN secretion in hypothyroid patients with normal thyroid function following levothyroxine (L-T(4)) replacement therapy, and to associate plasma ApN levels with intima-media thickness (IMT) in the common carotid artery (CCA), an indicator of early atherosclerosis, and cardiovascular parameters including soluble thrombomodulin (sTM), a plasma endothelial injury marker. The CCA IMT and plasma levels of ApN and sTM were measured in 52 hypothyroid patients and in age-, sex- and body mass index (BMI)-matched normal control subjects. Thirty-six of the hypothyroid patients were further monitored for changes in these markers during 1 year in a euthyroid state induced by L-T(4) replacement therapy. Although the basal CCA IMT was significantly higher in hypothyroid patients [0.633 +/- 0.018 mm (mean +/- S.E.)] than in control subjects (0.552 +/- 0.022 mm, P < 0.005), both groups had similar baseline ApN and sTM levels [10.23 +/- 0.76 vs. 10.10 +/- 0.93 microg/ml: NS; and 2.58 +/- 0.14 vs. 2.68 +/- 0.20 ng/ml: NS, respectively]. Simple regression analysis revealed that plasma ApN was significantly correlated in a positive manner with age (r = 0.339, P = 0.015), HDL-cholesterol (r = 0.295, P = 0.048), and sTM (r = 0.490, P = 0.0005), but not with CCA IMT (r = 0.059, P = 0.742). In multivariate analysis, the plasma ApN level was significantly associated with that of sTM (r = 0.546, P = 0.0001) and with serum high-density lipoprotein (HDL)-cholesterol levels (r = 0.291, P = 0.029) in hypothyroid patients. During 1 year of L-T(4) replacement therapy, hypothyroid patients showed a significant decrease in CCA IMT, to 0.553 +/- 0.016 mm (P < 0.0001), a level comparable to normal controls, but no significant change in ApN (from 10.79 +/- 1.07 to 10.6 9+/- 1.14 microg/ml, NS) or sTM (from 2.59 +/- 0.15 to 2.74 +/- 0.18 ng/ml, NS). Hence, we provide evidence that ApN and sTM might not contribute to enhanced atherosclerosis, as reflected by increased CCA IMT in hypothyroid patients. However, this is the first report to demonstrate a positive and significant association of sTM with ApN. These data support the hypothesis that sTM is one of the determinant of ApN and thus suggest the presence of an sTM-associated regulatory mechanism for ApN secretion in hypothyroid patients.

Associations between physical activity, peripheral atherosclerosis and bone status in healthy Japanese women

The aim of this cross-sectional study was to investigate whether physical activity and bone status may affect arterial thickening and stiffening in healthy Japanese women. Healthy women (n = 149; mean age, 54 years) were recruited from those who participated in a local health check program at the Osaka City University Hospital. Physical activity was assessed by physical functioning score of SF-36, and bone status by bone mineral density (BMD) in lumbar spine and calcaneus osteo-sono index (OSI). Arterial wall thickening assessed by intima-media thickness (IMT) in common carotid artery (CA) and femoral artery (FA), and arterial wall stiffening by peak wave velocity (PWV) in heart-carotid (hc) and heart-femoral (hf) as central segment and in heart-brachial (hb) and femoral-ankle (fa) as peripheral segment, respectively. By Spearman Rank correlation, lumbar spine BMD was correlated negatively with CA IMT (rho = -0.225, p < 0.05) and FA IMT (rho = -0.215, p < 0.05), and calcaneus OSI with FA IMT (rho = -0.330, p < 0.0001) but not CA IMT (rho = -0051, p = 0.5335). Both lumbar spine BMD and calcaneus OSI correlated negatively with PWV in all segments (all p < 0.05). Physical functioning score correlated weakly but significantly in a negative manner with all PWV segments (all p < 0.05) but not IMT. Multiple regression analyses revealed a significant association of calcaneus OSI (beta = -0.240, p = 0.0039) but not lumbar spine BMD (beta = -0.067, p = 0.4541) with FA IMT, although neither lumbar spine BMD nor calcaneus OSI was associated with CA IMT. Furthermore, physical functioning score was independently associated with hb and fa PWV but not hc and hf PWV, suggesting the preferential association with peripheral segment including lower extremities. Neither lumbar spine BMD nor calcaneus OSI was associated with any segment of PWV. In conclusion, it was suggested that calcaneus OSI might be associated with arterial wall thickening preferentially in femoral artery, and that physical activity may be associated with arterial wall stiffening in peripheral segment including lower extremity but not in central segment in healthy Japanese women.

Normative values for intima-media thickness and distensibility of large arteries in healthy adolescents

OBJECTIVE

Sonographic evaluation of arterial wall morphology and elasticity is increasingly accepted as a non-invasive tool in cardiovascular assessment. Several studies suggest that intima-media thickness (IMT) and arterial elasticity indices may sensitively reflect different vasculopathic processes in children. However, normative values and the impact of adolescent growth are largely unknown.

METHODS

We assessed the IMT of the common carotid (cIMT) and femoral arteries (fIMT), carotid elasticity indices and interacting anthropometric factors in 247 healthy subjects aged 10-20 years.

RESULTS

cIMT, fIMT, incremental elastic modulus (Einc) and circumferential wall stress (CWS) were positively, and distensibility coefficient (DC) inversely, correlated with age, height, body mass index (BMI), systolic blood pressure (BP) and brachial pulse pressure (r = 0.56 to -0.45, P < 0.05 to 0.0001). DC (r = -0.29, P < 0.0001) and stiffness index beta (r = 0.25, P < 0.0001), but not Einc, were significantly associated with cIMT independently of age. All vascular parameters showed non-Gaussian distributions. Excessively high IMT was associated with BMI and pulse pressure above the 90th percentile, and elevated Einc with high-normal BMI. Multivariate analysis identified independent positive effects of standardized BMI and brachial pulse pressure on normalized cIMT, negative effects of systolic BP and cIMT on DC, a positive effect of cIMT on stiffness, and positive effects of systolic BP and BMI on Einc and CWS.

CONCLUSIONS

Morphological and functional measures of large arteries should be normalized to take account of changes during adolescence and skewed distributions. Relative body mass, systolic blood pressure and/or pulse pressure are determinants of IMT and elasticity.

Heritability of carotid artery distensibility in Hispanics: the Northern Manhattan Family Study

BACKGROUND AND PURPOSE

Reduced arterial distensibility has been introduced as a novel risk factor for atherosclerosis. The importance of the genetic contribution to variation in distensibility is largely unknown. The purpose of this study was to estimate heritability of carotid distensibility.

METHODS

The ongoing Northern Manhattan Family Study recruits high-risk Caribbean Hispanic families to study genetic effects on stroke/cardiovascular risk factors. The distensibility metrics (strain, stiffness, distensibility, and elastic modulus) were measured from the right common carotid artery, and the heritability for each was estimated. Variance component methods were used to estimate age- and sex-adjusted heritability. Correlations were calculated to evaluate the relationship between distensibility phenotypes and intimamedia thickness (IMT) at each carotid segment.

RESULTS

The current data included 88 probands and 605 relatives from 88 families. Age- and sex-adjusted heritability was 25% for strain, 17% for distensibility, 20% for stiffness, and 20% for elastic modulus. Without adjustment for covariates, strong correlations were found between distensibility metrics and IMT: the absolute values of correlation coefficients were between 0.2 and 0.5, and all P values were <0.001. However, the correlation coefficients were reduced substantially after adjusting for age and sex.

CONCLUSIONS

These results suggested that genetic factors explained a moderate proportion of the variability of carotid distensibility. The correlations between distensibility and IMT were mainly attributable to age and sex effects. The regulation of carotid distensibility and IMT may reflect different underlying genetic and environmental mechanisms.

Findings of Doppler Sonography Do Not Correlate With Serum Lipoprotein and Total Homocysteine Concentrations in Renal Transplant Recipients

Atherosclerosis may be evaluated by structural or functional changes of the main arteries. We sought to investigate the probable associations of static and dynamic arterial changes with lipoprotein (a) and homocysteine levels, the two risk factors for atherosclerosis. Intima-media thickening and vasodilatory responses to nitroglycerine of the common carotid artery and the renal transplant artery were studied by color Doppler sonography in 75 renal transplant recipients and 30 controls. At 3, 5, and 10 minutes after 0.4 mg of sublingual nitroglycerine are measured resistive index and peak systolic velocity of the common carotid artery and renal transplant artery. Intima-media thickening in renal transplant recipients and controls were 0.86 +/- 0.34 mm and 0.74 +/- 0.14 mm (P = .05), respectively. Although intima-media thickness did not correlate with the duration of renal transplantation, it was significantly higher in older renal transplant recipients. Peak systolic velocity of common carotid artery was significantly decreased by nitroglycerine in the controls (81.8 +/- 16.7 m/s to 73.2 +/- 12.8 m/s, P = .03). This decrement was more obvious in renal transplant recipients, especially at 10 minutes (69.6 +/- 18.5 m/s vs 59.3 +/- 2 m/s, P = .01). These reductions did not correlate with intima-media thickening, latter of which also did not correlate with homocysteine concentrations, which were higher among renal transplant patients with creatinine more than 1.8 mg/dL. Basal resistive indices of the common carotid artery and renal transplant artery were higher among graft recipients with dysfunction than recipients with good function, (0.7 vs 0.59, P = .003). In conclusion, neither homocysteine nor lipoprotein(a) concentrations predict static and dynamic vascular properties.

Age-adjusted reference limits for carotid intima-media thickness as better indicator of vascular risk: population-based estimates from the VITA project

BACKGROUND

An increase of carotid intima-media thickness (CIMT) has been demonstrated to be associated in many studies with the subsequent risk of cardio- and cerebrovascular events, but the threshold level of CIMT for an increased risk at different ages remains uncertain.

OBJECTIVES

We aimed at establishing optimal reference limits associated with a definite increased vascular risk in the general population.

METHODS

A cohort of 2580 subjects was enrolled in a population-based cross-sectional survey. CIMT was measured on both left and right common carotid arteries, and age-specific, percentile-based reference ranges for CIMT were computed together with the Framingham risk score.

RESULTS

A significant, steady increase of CIMT reference ranges was observed within different age strata. CIMT levels were linearly related with an increase of the Framingham risk score, but after age-adjustment only the upper CIMT quintile was associated with a higher Framingham risk score.

CONCLUSIONS

Age-specific reference limits provide better estimate of vascular risk in the population and correlation with established risk factors.

Effect of increased convective clearance by on-line hemodiafiltration on all cause and cardiovascular mortality in chronic hemodialysis patients - the Dutch CONvective TRAnsport STudy (CONTRAST): rationale and design of a randomised controlled trial [ISRCTN38365125]

Background

The high incidence of cardiovascular disease in patients with end stage renal disease (ESRD) is related to the accumulation of uremic toxins in the middle and large-middle molecular weight range. As online hemodiafiltration (HDF) removes these molecules more effectively than standard hemodialysis (HD), it has been suggested that online HDF improves survival and cardiovascular outcome. Thus far, no conclusive data of HDF on target organ damage and cardiovascular morbidity and mortality are available. Therefore, the CONvective TRAnsport STudy (CONTRAST) has been initiated.

Methods

CONTRAST is a Dutch multi-center randomised controlled trial. In this trial, approximately 800 chronic hemodialysis patients will be randomised between online HDF and low-flux HD, and followed for three years. The primary endpoint is all cause mortality. The main secondary outcome variables are fatal and non-fatal cardiovascular events.

Conclusion

The study is designed to provide conclusive evidence whether online HDF leads to a lower mortality and less cardiovascular events as compared to standard HD.

Carotid stiffness and the risk of new vascular events in patients with manifest cardiovascular disease. The SMART study

AIMS

To study whether arterial stiffness is related to risk of new vascular events in patients with manifest arterial disease and to examine whether this relation varies between patients who differ with respect to baseline vascular risk, arterial stiffness, or systolic blood pressure (SBP).

METHODS AND RESULTS

The study was performed in the first consecutive 2183 patients with manifest arterial disease enrolled in the SMART study (Second Manifestations of ARTerial disease), a cohort study among patients with manifest arterial disease or cardiovascular risk factors. Common carotid distension (i.e. the change in carotid diameter in systole relative to diastole) was measured at baseline by ultrasonography. With the distension, several stiffness parameters were determined. In the entire cohort, none of the carotid artery stiffness parameters was related to the occurrence of vascular events. However, decreased stiffness was related to decreased vascular risk in subjects with low baseline SBP. The relation of carotid stiffness with vascular events did not differ between tertiles of baseline risk and carotid stiffness.

CONCLUSION

Carotid artery stiffness is no independent risk factor for vascular events in patients with manifest arterial disease. However, in patients with low SBP, decreased carotid stiffness may indicate a decreased risk of vascular events.

Increased levels of serum osteoprotegerin in hypothyroid patients and its normalization with restoration of normal thyroid function

Hypothyroidism is associated with increased morbidity from cardiovascular disease, and an increase in serum osteoprotegerin (OPG) has recently been reported to be associated with the severity of coronary heart disease and cardiovascular mortality. The present study was designed to examine whether hypothyroidism causes an increase in serum OPG, and to determine whether levothyroxine (L-T4) replacement therapy might suppress serum OPG levels in hypothyroid patients. Fifty-three hypothyroid patients with chronic thyroiditis and age- and sex-matched normal control subjects were examined for the levels of serum OPG and plasma von Willebrand factor (vWF), a vascular injury marker. Thirty-seven of the hypothyroid patients were further monitored for changes in these markers during 1 year in a euthyroid state induced by L-T4 replacement therapy. Baseline OPG was significantly higher in hypothyroid patients than in normal controls (4.51 +/- 0.50 vs 3.72 +/- 0.23 pmol/l (mean +/- S.E.); P = 0.0182). In multivariate analysis, baseline OPG was significantly associated with baseline levels of TSH (r = 0.280, P = 0.0162) and vWF (r = 0.626, P < 0.0001). During one year of L-T4 replacement therapy, hypothyroid patients showed a significant decrease in OPG levels from 4.35 +/- 0.51 to 3.48 +/- 0.26 pmol/l (P = 0.0166), a level comparable to normal controls. The change in serum OPG levels during L-T4 replacement therapy was significantly and independently associated in a negative fashion with baseline vWF (r = -0.503, P = 0.0014). This study suggested that the severity of hypothyroidism and vascular injury might have important independent roles in increasing the serum OPG level in hypothyroid patients. Furthermore, it was demonstrated that a sustained euthyroid state might have the potential to decrease the serum OPG level in hypothyroid patients and that the degree of vascular injury in the hypothyroid state is independently associated with a decrease in serum OPG during a 1-year normalization of thyroid function.

Evaluation of carotid artery wall thickness with high-resolution sonography in obstructive sleep apnea syndrome

PURPOSE

An increased intima-media thickness (IMT) in the carotid arteries is a marker of generalized atherosclerosis, and it has been associated with a high risk of stroke. The aim of this study was to investigate whether patients with obstructive sleep apnea syndrome (OSAS) have an increase in atherosclerotic indicators in the carotid arteries.

METHODS

We studied 30 men with severe OSAS who had an apnea-hypopnea index (AHI) of at least 20. IMT measurement and the presence of stenotic occlusive lesions in the carotid arteries (right common carotid artery [RCCA], right bulb [Rbulb], right internal carotid artery [RICA], left common carotid artery [LCCA], left bulb [Lbulb], and left internal carotid artery [LICA]) were investigated by high-resolution sonography. Results of the sonographic examinations were compared with those for a group of 20 subjects with mild OSAS (AHI <20) and 20 healthy subjects.

RESULTS

The mean IMT of the carotid arteries of patients with severe OSAS was significantly higher than those of patients with mild OSAS and control subjects (RCCA 0.81 versus 0.63 versus 0.58, p <0.01; Rbulb 0.96 versus 0.87 versus 0.65, p <0.001; RICA 0.77 versus 0.69 versus 0.61, p <0.05; LCCA 0.97 versus 0.78 versus 0.67, p <0.01; Lbulb 1.01 versus 0.89 versus 0.72, p <0.01; LICA 0.91 versus 0.75 versus 0.65, p <0.001).

CONCLUSIONS

This study shows that the carotid arteries' IMT is increased in patients with severe OSAS. This increase may predispose the patients to cerebrovascular disease. Additionally, the findings support the hypothesis that patients with OSAS are at risk of developing cerebrovascular disease regardless of the presence or absence of other vascular risk factors (eg, hypercholesterolemia, diabetus mellitus, and hypertension).

Significance of intima-media thickness in femoral artery in the determination of calcaneus osteo-sono index but not of lumbar spine bone mass in healthy Japanese people

The aim of this cross-sectional study was to investigate whether physical activity and local arterial thickening may affect bone metabolism. To analyze the effects of physical activity and atherosclerosis on bone in healthy Japanese people, health-related quality of life (HRQL) and local arterial thickening were assessed by means of the Medical( )Outcomes Study 36-item Short Form (SF-36), and intimal-medial thickness (IMT) in common carotid artery (CA) and femoral artery (FA), respectively. Bone mineral density (BMD) in lumbar spine was measured by dual X-ray absorptiometry and the osteo-sono assessment index (OSI) of the calcaneus by ultrasound. Healthy subjects (106 male and 154 female) were recruited from those who participated in a local health check program at the Osaka City University Hospital. A significant correlation existed between lumbar spine BMD and calcaneus OSI (r=0.551, P<0.0001). Among various scores in SF-36, only physical functioning score correlated weakly but significantly in a positive manner with lumbar spine BMD (rho=0.156, P=0.0147) and calcaneus OSI (rho=0.190, P=0.0024). Lumbar spine BMD correlated negatively with FA IMT (rho=-0.191, P=0.0027) whereas calcaneus OSI with FA IMT (rho=-0.199, P=0.0014). Multiple regression analyses revealed a significant association between FA IMT and calcaneus OSI, whereas lumbar spine BMD did not correlate significantly with FA or CA IMT. When subjects were restricted to female, FA IMT, but not CA IMT, still showed tendency against independent factors negatively associated with calcaneus OSI. Furthermore, lumbar spine BMD, but not calcaneus OSI, was weakly but significantly associated with increased physical functioning score independently. In conclusion, it was suggested that physical activity may affect bone strength in lumbar spine and calcaneus and that FA IMT might be a significant determinant of bone strength in calcaneus, but not in lumbar spine, in healthy Japanese subjects.

Decrease of arterial stiffness at common carotid artery in hypothyroid patients by normalization of thyroid function

This study examined the effect of hypothyroidism on arterial stiffening and the effect of levothyroxine (l-T(4)) replacement. The arterial stiffness index beta (stiffness beta) and intima-media thickness (IMT), a parameter of arterial stiffening and thickening, respectively, were determined in common carotid artery (CCA) by ultrasonography in 30 hypothyroid patients before and after 1 year of normalization of thyroid function by l-T(4) replacement. Baseline CCA stiffness beta and IMT was significantly higher in the hypothyroid patients than in age- and sex-matched normal controls [9.46 +/- 0.93 vs. 8.02 +/- 0.91 (mean +/- SE); P < 0.05, 0.635 +/- 0.018 mm vs. 0.541 +/- 0.019 mm; P < 0.005, respectively]. In multivariate analysis, baseline stiffness beta was significantly associated with baseline levels of IMT (r = 0.457, P = 0.0311), FT(4) (r = -0.413, P = 0.0169), and a plasma vascular injury marker, von Willebrand factor (vWF) (r = 0.412, P = 0.0261). During 1 year of euthyroidism, 22 and 29 out of 30 patients showed significant decreases of stiffness beta and IMT to normal respective level, from 9.46 +/- 0.93 to 7.58 +/- 0.34 and from 0.635 +/- 0.018 to 0.552 +/- 0.015 mm, respectively. Change in stiffness beta during l-T(4) therapy correlated significantly in a negative manner with baseline levels of age (r = -0.465, P = 0.011) and IMT (r = -0.406, P = 0.029). Stiffness beta after but not before l-T(4) therapy showed a tendency towards a positive correlation with age. This study suggested that increases of arterial thickening, and plasma vWF, and a reduction in serum FT(4) might have an important role independently in the increased arterial stiffening in hypothyroid patients. Furthermore, it was demonstrated that sustained euthyroidism might have the potential to reverse arterial stiffening in addition to thickening in hypothyroid patients.

Atherosclerotic disease regression with statins: studies using vascular markers

Vascular imaging techniques enable identification of atherosclerosis in the sub-clinical phase and allow assessment of interventions to modify disease progression. Angiography has limited utility for tracking the progression of atherosclerosis because of its invasive nature, limited sensitivity for detecting early lesions and relatively low interscan reproducibility. Intravascular ultrasound (IVUS)an electron beam computed tomography (EBCT) are more sensitive and reproducible; however, available data on their ability for tracking disease progression are few. Measurement of carotid intima media thickness (CIMT) by B-mode ultrasound is a well-validated procedure for this application. In comparison with angiography, CIMT demonstrates greater sensitivity for detecting early atherosclerosis and lipid-rich plaques that are vulnerable to rupture. Continued validation and development of imaging techniques, such as magnetic resonance imaging (MRI), will facilitate the assessment of atherosclerosis progression in intervention studies. Stains are effective low-density lipoprotein cholesterol (LDL-C) lowering agents, and imaging studies have demonstrated their ability to slow progression and promote regression of atherosclerosis. The benefits of therapy on atherosclerosis regression appear to extend to soft atherosclerotic plaques that are still developing and treatment effects are independent of baseline LDL-C level. Hence, imaging studies support early intervention with statins in coronary heart disease patients, irrespective of lipid level.

Determination of vessel size: a putative framework to assess clinical outcome

BACKGROUND

Unknown is the predictive value of the coronary artery diameter without the administration of vasomotor stimuli. A small reference diameter of the target vessel has been demonstrated to be an adverse prognostic factor in patients undergoing revascularisation. The present study investigated the prognostic value of the proximal non-stenotic left anterior descending coronary artery (LAD) diameter in patients referred for a first diagnostic angiogram without a previous revascularisation.

METHODS

A total of 277 patients (mean age 57 year, 61% male) were eligible for analysis. The proximal non-stenotic diameter of the LAD was measured by quantitative coronary angiography without prior nitrate infusion. We defined a small LAD as a diameter < or =2.5 mm. Cardiovascular events were defined as cardiac death, myocardial infarction, and hospitalizations for unstable angina.

RESULTS

During a median follow-up of 47 months, 24 major cardiac events occurred. The cumulative survival for patients with a small LAD was significantly lower, than for patients with a large LAD (hazard ratio 2.51; 95% confidence interval 1.11-5.66, p=0.03). In the multivariate analysis, a LAD diameter < or =2.5 mm remained a significant predictor of cardiovascular events after adjustment for age, gender, and the presence of significant coronary artery disease (hazard ratio 2.32; 95% confidence interval 1.01-5.34, p=0.048).

CONCLUSION

In patients referred for a first diagnostic angiogram without a previous revascularisation, the diameter of the proximal non-stenotic LAD is an independent predictor of cardiovascular events.

Association of mitral annulus calcification, aortic valve calcification with carotid intima media thickness

Background

Mitral annular calcification (MAC) and aortic annular calcification (AVC) may represent a manifestation of generalized atherosclerosis in the elederly. Alterations in vascular structure, as indexed by the intima media thickness (IMT), are also recognized as independent predictors of adverse cardiovascular outcomes.

Aim

To examine the relationship between the degree of calcification at mitral and/or aortic valve annulus and large artery structure (thickness).

Methods

We evaluated 102 consecutive patients who underwent transthoracic echocardiography and carotid artery echoDoppler for various indications; variables measured were: systemic blood pressure (BP), pulse pressure (PP=SBP-DBP), body mass index (BMI), fasting glucose, total, HDL, LDL chlolesterol, triglycerides, cIMT. The patients were divided according to a grading of valvular/annular lesions independent scores based on acoustic densitometry: 1 = annular/valvular sclerosis/calcification absence; 2 = annular/valvular sclerosis; 3 = annular calcification; 4 = annular-valvular calcification; 5 = valvular calcification with no recognition of the leaflets.

Results

Patient score was the highest observed for either valvular/annulus. Mean cIMT increased linearly with increasing valvular calcification score, ranging from 3.9 ± 0.48 mm in controls to 12.9 ± 1.8 mm in those subjects scored 5 (p < 0.0001). In the first to fourth quartile of cIMT values the respective maximal percentual of score were: score 1: 76.1%, score 2: 70.1%, score 4: 54.3% and score 5: 69.5% (p > 0.0001).

Conclusion

MAC and AVC score can identify subgroups of patients with different cIMT values which indicate different incidence and prevalence of systemic artery diseases. This data may confirm MAC-AVC as a useful important diagnostic parameter of systemic atherosclerotic disease.

Degree of atherosclerosis predicts short-term commitment for smoking cessation therapy

BACKGROUND

Only little is known about factors that influence the smokers' propensity to start smoking cessation therapy and stay within such programs.

METHODS

One hundred fifteen subjects that were current smokers and presented at the angiologic outpatient unit were enrolled in a prospective cohort study. All patients were invited to take part in a smoking cessation program. Patients' history, noninvasive vascular, cardiac, and pulmonary parameters, state of atherosclerotic disease (SMART-score), smoking history, and Fagerström index were obtained and the carbon monoxide breathing test was performed.

RESULTS

Lower age and heavy smoking were associated with less propensity to start smoking cessation therapy. The degree of atherosclerosis significantly predicted short-term commitment to smoking cessation therapy (relative risk for discontinuation: 0.82; 95% CI: 0.70-0.96). Single factors predictive for staying within the therapy were peripheral arterial occlusive disease and hyperlipidemia, while neither prior myocardial infarction nor pulmonary function was associated with compliance. Fifty-four percent of patients that completed 3 months of therapy quit smoking.

CONCLUSIONS

Counseling in smokers with preexistent or newly diagnosed atherosclerotic diseases or risk factors should include their specific vascular condition and information on positive consequences on the progress of these conditions. Counseling for initiation of smoking cessation therapy should apply different strategies as used in the maintenance phase of therapy.

IgM antibody level against proinflammatory bacterial peptidoglycan is inversely correlated with extent of atherosclerotic disease

OBJECTIVE

Atherosclerosis may lead to acute clinical events by rupture of a vulnerable atherosclerotic plaque. Previously, we demonstrated that peptidoglycan (PGN), a major cell wall component of gram-positive bacteria that induces production of proinflammatory cytokines through TLR2 and CD14, is prevalent in atherosclerotic lesions with histological features associated with plaque vulnerability. We hypothesized that in atherosclerotic patients antibody levels against PGN may differ compared with matched controls.

METHODS AND RESULTS

ELISA was performed to measure immunoglobulin levels against PGN in sera of 80 atherosclerotic patients versus 77 control patients with an increased cardiovascular risk, frequency-matched for age, sex and risk factors for atherosclerotic disease. In all patients and controls, intima-media (IMT) thickness was assessed using an array transducer. Significantly lower levels of IgM directed against PGN were found in atherosclerotic patients compared with the control patients without clinically manifested disease (P = 0.02). The IgM levels against PGN decreased with increasing mean common carotid IMT thickness (P = 0.006).

CONCLUSIONS

These results show that patients suffering from atherosclerotic disease have decreased IgM levels against PGN. The data suggest that an antibody response against PGN could have a protective effect against the development or activity of atherosclerotic disease.

Carotid haemodynamic parameters as risk factors for cerebral infarction in Type 2 diabetic patients

AIMS

The purpose of this study was to investigate the usefulness of carotid haemodynamic parameters, i.e. the resistive index (RI) and the pulsatility index (PI), in estimating the risk of cerebral infarction in Type 2 diabetic patients.

METHODS

Three hundred and eighty-two Type 2 diabetic patients (223 men and 159 women; mean age 61 years, range 40-88; 40 had a history of cerebral infarction) and 110 control subjects were analysed in a cross-sectional study. All subjects underwent ultrasonography of the common carotid artery, with determination of intima-media thickness (IMT), RI, and PI. A SMART (Second Manifestations of ARTerial Disease) atherosclerosis risk score was determined for all diabetic patients.

RESULTS

The mean values for IMT, RI, and PI were increased in diabetic patients compared with control subjects, and they were significantly elevated in patients with previous cerebral infarction compared with patients without cerebral infarction. (IMT 0.88 +/- 0.22 vs. 0.77 +/- 0.19, P < 0.005; RI 0.77 +/- 0.07 vs. 0.75 +/- 0.06, P < 0.05; PI 1.88 +/- 0.36 vs. 1.71 +/- 0.36, P < 0.01) Significant but weak correlations were found between SMART risk scores and IMT, RI and PI (IMT r = 0.390, P < 0.0001; RI r = 0.346, P < 0.0001; PI r = 0.393, P < 0.0001). The multiple logistic model showed that both the IMT [odds ratio (OR) 6.50, 95% confidence interval (CI) 3.42, 12.34] and the PI (OR 4.16, 95% CI 2.36, 7.34) were independent risk factors for cerebral infarction. The subjects who had an IMT of > 1.0 and a PI > 2.00 had a greater risk of developing a cerebral infarction than did the subjects who had an IMT of < 1.0 and a PI < 2.00 (OR 6.21, 95% CI 2.26, 17.05).

CONCLUSIONS

The results of this cross-sectional study showed that the measurement of haemodynamic parameters was useful, together with IMT, in estimating the risk of previous cerebral infarction in Type 2 diabetic patients. The predictive value of these parameters in identifying the risk of future cerebral infarction must await the results of future prospective studies.

Association between pulse pressure, carotid intima–media thickness and carotid and/or iliofemoral plaque in hypertensive patients

Increased common carotid artery intima-media thickness (CCA-IMT) and carotid and/or iliofemoral (C/IF) plaque are frequent in subjects treated for hypertension, but their association with pulse pressure (PP) has rarely been studied. Using ultrasound techniques, CCA-IMT and C/IF plaques were studied in 323 hypertensive subjects, who were classified into four groups according to the adequacy of blood pressure (BP) control (systolic BP (SBP) <140 mmHg and diastolic BP (DBP) <90 mmHg) and PP (high or low). After adjustment for confounding variables, an increase in CCA-IMT was the only factor significantly and independently associated with high PP, irrespective of the effectiveness of blood pressure control and of antihypertensive drug treatment. CCA-IMT correlated with age, PP, waist-to-hip ratio, tobacco consumption, and heart rate. C/IF plaques correlated with age, tobacco consumption, diabetes mellitus, and dyslipidaemia. To conclude, even with SBP<140 mmHg and DBP<90 mmHg on treatment, hypertensive subjects may have increased CCA-IMT values and C/IF plaque. Four cardiovascular risk factors seem to be involved in these alterations, namely tobacco consumption, dyslipidaemia, diabetes and increased PP. Only the latter factor does not have a standardized effective treatment.

The Role of Exercise in the Treatment of Cardiovascular Disease Associated with Type 2 Diabetes Mellitus

The role of exercise training in the prevention and treatment of type 2 diabetes mellitus has been studied extensively over the past two decades. Although the primary treatment aim for patients with type 2 diabetes is metabolic control, the morbidity and mortality associated with the disease is more a function of cardiovascular disease. As exercise is associated with favourable reductions in the risk for cardiovascular disease in other high-risk populations, here we explore the role of exercise in the treatment of cardiovascular maladaptations associated with type 2 diabetes. The cardiovascular adaptation to type 2 diabetes is characterised by hypertrophy, stiffening and loss of functional reserve. Clinically, the cardiovascular adaptations to the diabetic state are associated with an increased risk for cardiovascular disease. Functionally, these adaptations have been shown to contribute to a reduced exercise capacity, which may explain the reduced cardiovascular fitness observed in this population. Exercise training is associated with improved exercise capacity in various populations, including type 2 diabetes. Several structural and functional adaptations within the cardiovascular system following exercise training could explain these findings, such as reductions in ventricular and vascular structural hypertrophy and compliance coupled with increased functional reserve. Although these cardiovascular adaptations to aerobic exercise training have been well documented in older populations with similar decrements in cardiovascular fitness and function, they have yet to be examined in patients with type 2 diabetes. For this reason, we contend that exercise training may be an excellent therapeutic adjunct in the treatment of diabetic cardiovascular disease.

Detection of lumen-intima interface of posterior wall for measurement of elasticity of the human carotid artery

In our series of studies on noninvasive assessment of the regional elasticity of the arterial wall, the displacement gradient (change in thickness) of the arterial wall caused by the heartbeat was measured by the phased-tracking method. Because the displacement gradient corresponds to the strain due to the change in blood pressure, the elasticity can be evaluated from the displacement gradient of the arterial wall and the blood pressure, which are noninvasively measured at the upper arm. In the measurement of the elasticity of the arterial wall by our method, the region in which the elastic modulus is estimated must be assigned beforehand; currently, the lumen-intima boundary of the arterial wall is manually determined by the operator. For the real-time measurement of the elasticity of the arterial wall, a fast, automated method is necessary for detection of the boundary. In this paper, a cost function is proposed for differentiation of the arterial wall from the lumen. The proposed cost function was applied to ultrasound data, which were noninvasively obtained for five human carotid arteries. In comparison with the case of detection using only the amplitude of the echo, the root mean square error between the automatically detected lumen-intima boundary and the manually assigned boundary was significantly improved by using the proposed cost function. Furthermore, the lumen-intima boundary was automatically detected in a short period. Such a method is required for real-time measurement of the elasticity of the arterial wall, though detection of the outer boundary of the adventitia, which is not described in this paper, is also necessary to realize real-time elasticity measurement by our method.

Inflammation and bone resorption as independent factors of accelerated arterial wall thickening in patients with rheumatoid arthritis

OBJECTIVE

We recently reported that rheumatoid arthritis (RA) patients had increased intima-media thickness (IMT) of the common carotid artery (CCA). The present longitudinal study was performed to determine whether the change in arterial thickness was accelerated in RA patients and to determine which factor was important in the progression of arterial wall changes.

METHODS

We studied 62 female RA patients with stable disease activity and 63 healthy female controls. IMT of the CCA was measured twice by high-resolution B-mode ultrasonography. The second examination was performed 18-36 months after the first, and changes were expressed as millimeters of increase per year. Baseline examinations included blood markers of inflammation and urinary calcium excretion (expressed as the calcium-to-creatinine ratio).

RESULTS

RA patients showed a significantly greater increase in IMT of the CCA compared with controls. In univariate analyses of the RA patient data, the C-reactive protein (CRP) level correlated with the increase in CCA IMT. Other markers of inflammation (the erythrocyte sedimentation rate and white blood cell and platelet counts) also showed significant positive associations with the annual increase in CCA IMT in multiple regression models when adjusted for age, smoking status, blood pressure, and serum cholesterol level. The urinary calcium-to-creatinine ratio was also significantly associated with an increase in CCA IMT. Moreover, both the CRP level and the urinary calcium-to-creatinine ratio were significantly and independently associated with the increase in IMT of the CCA.

CONCLUSION

Patients with RA have a higher rate of increase in thickening of the arterial wall. Inflammation and calcium mobilization are factors closely associated with the accelerated arterial wall changes.

Increased prevalence of severe subclinical atherosclerotic findings in long-term treated rheumatoid arthritis patients without clinically evident atherosclerotic disease

We conducted the current study to search for subclinical atherosclerosis in patients with rheumatoid arthritis (RA) without clinically evident atherosclerosis or its complications who had been treated for a long duration, and to assess whether demographic or clinical factors affect the development of atherosclerotic disease. Forty-seven white patients fulfilling the 1987 American College of Rheumatology classification criteria for RA were recruited from Hospital Xeral-Calde, Lugo, Spain. Patients were required to have been treated for at least 5 years, including current treatment with 1 or more disease-modifying antirheumatic drugs. Patients with diabetes mellitus, renal insufficiency, hypertension, cardiovascular or cerebrovascular disease, and smokers were excluded. Forty-seven matched controls were also studied. Carotid intima-media wall thickness (IMT) and carotid plaques were measured in the right common carotid artery. The study was performed using high-resolution B-mode ultrasound. Patients had greater carotid IMT (0.779 +/- 0.164 mm) than did controls (0.699 +/- 0.129 mm); (p = 0.010). Sixteen (34%) patients showed carotid plaques compared with only 7 (15%) controls (p = 0.031). There was a positive correlation between the age at the time of study and the carotid IMT. Patients with carotid plaques had significantly greater carotid IMT (0.859 +/- 0.116 mm) than those without plaques (0.739 +/- 0.171 mm) (p = 0.014). Also, RA patients with carotid plaques had a significantly longer disease duration (mean, 21.0 yr) and more extraarticular manifestations (63%) than those without plaques (mean, 12.7 yr and 26%, respectively). Age at the time of the study and disease duration were the best predictive factors for the development of severe morphologic expression of atherosclerotic disease. The present study confirms an increased frequency of severe subclinical atherosclerotic findings in long-term actively treated RA patients from northwest Spain.