Noninvasive tests of vascular function and structure: why and how to perform them

Age and Interleukin-15 Levels Are Independently Associated With Intima-Media Thickness in Obesity-Related NAFLD Patients

Common carotid intima-media thickness (IMT) represents a functional and structural marker of early, precocious, and subclinical atherosclerosis, independently from the carotid plaque. Macrophage cells, which have been detected in adipose tissue and atherosclerotic plaques, are regulated by interleukin-15 (IL-15). At the light of the conflicting results concerning the role of IL-15 in atherosclerosis, the aim of the study was to retrospectively evaluate in a population of 80 obese patients, with median age of 46 years (IQR 34–53 years), with a low rate of comorbidities but with non-alcoholic fatty liver disease (NAFLD) or hepatic steatosis (HS), the relationship between IMT and serum concentrations of IL-15. Anthropometric measures, metabolic profile, and serum inflammatory markers, as well as the levels of IL-15, MCP-1, b FGF, and GM-CSF, were analyzed by a bead-based assay. IMT, HS, subcutaneous, and visceral adipose tissues were detected by ultrasonography. The IL-15 levels of the obese patients were increased with respect to those of 44 young healthy subjects, i.e., 2.77 (1.21–4.8) vs. 1.55 (1–2.4) pg/mL (P = 0.002). In the univariate analysis, IL-15 levels were associated to IMT and to those of MCP-1, b FGF, and GM-CSF, without any relation to other inflammatory markers such as CRP and ferritin, except fibrinogen. In the multivariate analysis, after adjusting the HS severity for the extent of visceral adiposity, a dramatic change in prediction of IMT by HS was shown (β from 0.29 to 0.10, P from 0.008 to 0.37). When the visceral adipose tissue was combined with IL-15, on the one hand, and the well-known coronary artery disease (CAD) risk factors—i.e., age, gender, smoking status, HDL-cholesterol concentrations, triglycerides levels, and HOMA—on the other, only age and IL-15 remained the predictors of IMT (β = 0.60, P = 0.0001 and β = 0.25, P = 0.024, respectively). There was no association of IL-15 with various anthropometric parameters nor with body fat distribution and severity of HS, also after adjusting for age. Age is resulted to be the main factor in the prediction of IMT and thus of early atherosclerosis. The prediction of IMT by IL-15 coupled with the lack of prediction by the well-known CAD risks is in agreement with recent data, which emphasizes the main role of the immune system in the onset/worsening of atherosclerosis, even though the role of visceral adiposity should be further deepened. Age and IL-15 levels were both predictors of early atherosclerosis in this population of obese patients with NAFLD, suggesting a possible role of this cytokine in the atherosclerosis process.

Use of perfusional CBCT imaging for intraprocedural evaluation of endovascular treatment in patients with diabetic foot: a concept paper

Diabetes mellitus (DM) is one of the most common metabolic diseases worldwide; its global burden has increased rapidly over the past decade, enough to be considered a public health emergency in many countries. Diabetic foot disease and, particularly diabetic foot ulceration, is the major complication of DM: through a skin damage of the foot, with a loss of epithelial tissue, it can deepen to muscles and bones and lead to the amputation of the lower limbs. Peripheral arterial disease (PAD) in patients with diabetes, manifests like a diffuse macroangiopathic multi-segmental involvement of the lower limb vessels, also connected to a damage of collateral circulation; it may also display characteristic microaneurysms and tortuosity in distal arteries. As validation method, Bold-MRI is used. The diabetic foot should be handled with a multidisciplinary team approach, as its management requires systemic and localized treatments, pain control, monitoring of cardiovascular risk factors and other comorbidities. CBCT is an emerging medical imaging technique with the original feature of divergent radiation, forming a cone, in contrast with the spiral slicing of conventional CT, and has become increasingly important in treatment planning and diagnosis: from small anatomical areas, such as implantology, to the world of interventional radiology, with a wide range of applications: as guidance for biopsies or ablation treatments. The aim of this project is to evaluate the usefulness of perfusion CBCT imaging, obtained during endovascular revascularization, for intraprocedural evaluation of endovascular treatment in patients with diabetic foot. (www.actabiomedica.it).

Tofogliflozin does not delay progression of carotid atherosclerosis in patients with type 2 diabetes: a prospective, randomized, open-label, parallel-group comparative study

BACKGROUND

This study aimed to investigate the preventive effects of tofogliflozin, a selective sodium-glucose cotransporter 2 (SGLT2) inhibitor, on atherosclerosis progression in type 2 diabetes (T2DM) patients without apparent cardiovascular disease (CVD) by monitoring carotid intima-media thickness (IMT).

METHODS

This prospective, randomized, open-label, blinded-endpoint, multicenter, parallel-group, comparative study included 340 subjects with T2DM and no history of apparent CVD recruited at 24 clinical units. Subjects were randomly allocated to either the tofogliflozin treatment group (n = 169) or conventional treatment group using drugs other than SGLT2 inhibitors (n = 171). Primary outcomes were changes in mean and maximum common carotid IMT measured by echography during a 104-week treatment period.

RESULTS

In a mixed-effects model for repeated measures, the mean IMT of the common carotid artery (mean-IMT-CCA), along with the right and left maximum IMT of the CCA (max-IMT-CCA), significantly declined in both the tofogliflozin (- 0.132 mm, SE 0.007; - 0.163 mm, SE 0.013; - 0.170 mm, SE 0.020, respectively) and the control group (- 0.140 mm, SE 0.006; - 0.190 mm, SE 0.012; - 0.190 mm, SE 0.020, respectively). Furthermore, the tofogliflozin and the conventional treatment group did not significantly differ in the progression of the mean-IMT-CCA (mean change (95% CI) 0.008 (- 0.009, 0.025) mm, P = 0.34), along with the right (mean change (95% CI) 0.027 (- 0.005, 0.059) mm, P = 0.10) and the left max-IMT-CCA (mean change (95% CI) 0.020 (- 0.030, 0.070), P = 0.43). Similar findings were obtained even after adjusting for traditional CV risk factors and/or administration of drugs at baseline. Relative to the control treatment effects, tofogliflozin significantly reduced the HbA1c, blood glucose level, body weight/body mass index, abdominal circumference, and systolic blood pressure, and significantly increased the HDL-C. The total and serious adverse events incidences did not significantly vary between the treatment groups.

CONCLUSIONS/INTERPRETATION

No IMT changes were observed between the tofogliflozin and the conventional treatment groups. However, tofogliflozin is a safe and effective treatment option for managing primary CVD risk factors in this population. Clinical Trial Registration UMIN000017607 ( https://www.umin.ac.jp/icdr/index.html ).

Advanced Glycation End Products, a Potential Link between Psoriasis and Cardiovascular Disease: A Case-control Study

CONTEXT

Advanced glycation end products (AGEs) promote oxidative stress and inflammation by altering structure and function of proteins. They are excessively produced mainly in hyperglycemia, chronic inflammation and are involved in the development of atherosclerosis and cardiovascular disease.

AIMS

The aim of this study was to investigate whether skin AGEs levels were increased and had relation to premature atherosclerosis in patients with psoriasis.

SUBJECTS AND METHODS

Fifty-two psoriasis patients and 20 healthy controls (HC) were included. AGEs were determined by skin autofluorescence (SAF) analysis. High-sensitive C-reactive protein (hsCRP) and carotid intima-media thickness (CIMT) were also investigated. Physical activity and dietary patterns were determined.

STATISTICAL ANALYSIS USED

Fisher's exact test, two-sample t-tests, Mann-Whitney-U test, Pearson correlation, Spearman correlation, and Wilcoxon test.

RESULTS

SAFs were increased in psoriasis patients (1.8 arbitrary units [AUs]) compared to that in HC (1.6 AUs) (P = 0.057). Median CIMT values of HC and psoriasis groups were 0.43 (0.28-0.79), and 0.59 (0.44-0.98) respectively and the differences were significant (P = 0.001); hsCRP levels were not different between groups.

CONCLUSIONS

Skin AGE accumulation was found to have a correlation with CIMT in psoriasis patients providing evidence for the role of AGEs in premature atherosclerosis.

Prediction of carotid intima-media thickness in obese patients with low prevalence of comorbidities by serum copper bioavailability

BACKGROUND AND AIM

Western societies, with growing prevalence, suffer from various metabolic diseases like obesity and hepatic steatosis, better defined as non-alcoholic fatty liver disease, or cardiovascular (CV) diseases that are strictly linked to each other. The association of their occurrence with the altered homeostasis of metals is an intriguing issue. Copper in particular was identified as key player in various metabolic derangements. On these bases, we aimed at investigating the possible association of serum copper levels with an indicator of early CV risk as the intima-media thickness (IMT) of carotid artery and its predictive value in a selected population of obese patients.

METHODS

We performed a cross-sectional study recruiting 100 obese patients characterized by a low prevalence of comorbidities. Ultrasound investigation for hepatic steatosis and IMT evaluation were performed. Serum samples were collected and then analyzed through atomic absorption spectrometry to evaluate their copper content. Possible correlations between copper bioavailability and biochemical, clinical, and anthropometric characteristics of patients were sought.

RESULTS

Age negatively predicted copper serum levels of patients (P = 0.009). However, the most interesting finding is the negative prediction of IMT by the copper serum levels (t = -2.23, P = 0.028, least absolute deviations regression). Factor analysis confirmed the aforementioned inverse correlation and highlighted the strong inverse correlation between smoking and copper serum levels.

CONCLUSION

Our data show that an altered copper bioavailability predicts early atherosclerosis as main CV risk in obese patients with hepatic steatosis detected by ultrasound, shedding some light in this pathological scenario.

Do self-reported stress and depressive symptoms effect endothelial function in healthy youth? The LOOK longitudinal study

BACKGROUND AND AIMS

Endothelial dysfunction is thought to be an early indicator of risk for cardiovascular disease and has been associated with both stress and depression in adults and adolescents. Less is known of these relationships in younger populations, where the origins of CVD is thought to manifest. This study examined the effects of questionnaire derived psychosocial stress and depressive symptoms on endothelial function among children, following them through to adolescence.

METHOD

Participants were 203 grade 2 children (111 girls; M age = 7.6 ± 0.3 years) from the LOOK longitudinal study, who were followed through to adolescence (16 years). Self-reported psychosocial stress and depression were assessed using the validated Children's Stress Questionnaire and a modified and validated version of the Children's Depression Inventory respectively; endothelial function was assessed using EndoPAT 2000 system at follow-up only; and adjustments were made for fitness, pubertal development and socioeconomic status.

RESULTS

Although all relationships occurred in the hypothesised direction, no cross-sectional or prospective evidence of early symptoms of psychological stress or depression being associated with endothelial dysfunction was found among our asymptomatic cohort of adolescents (all p > .05).

CONCLUSIONS

In contrast to previous findings in adolescents, our data provided little evidence of any relationship between current or previous psychosocial stress or depression and endothelial function in 16-year-old boys and girls. However, our data need to be interpreted alongside the potential limitations in the sensitivity associated with self-report methods for detecting psychological distress of children.

Validation of an Automated Computerized Analyzing System for Measuring Common Carotid Artery Intima–Media Thickness by Brightness Mode Ultrasound

Background and Purpose

Evaluation of subclinical atherosclerosis by B-mode carotid ultrasound intima–media thickness (IMT) is an endorsed technique whose ease and precision is improved by use of automated IMT measurement algorithms. We report results of a validation study of SonoCalc, an automated IMT software program.

Methods

Three vascular sonographers measured the mean common carotid artery IMT twice of 120 near and far wall CCA segments from 30 subjects by manual electronic instrument calipers and with SonoCalc.

Results

Accuracy analysis indicated the equivalence of SonoCalc IMT measurements to those with manual electronic instrument calipers ( p < 0.0001). The coefficient of variation (CV) was calculated for each set of duplicate SonoCalc and manual electronic instrument calipers measurements. The average SonoCalc-manual electronic instrument calipers CV differences significantly favored SonoCalc ( p < 0.0001).

Conclusion

This study demonstrated that the use of the SonoCalc and the manual electronic instrument calipers produced measurements whose differences were statistically insignificant. Furthermore, the analysis to assess reproducibility of the two methods showed that the SonoCalc method was significantly more reproducible than the manual electronic instrument calipers methods.

Examining the Brachial Artery Reactivity Curve Measured by B-Mode Ultrasound in the Buffalo Cardio-Metabolic Occupational Police Stress (BCOPS) Pilot Study

Brachial artery reactivity was assessed in the Buffalo Cardio-Metabolic Occupational Police Stress (BCOPS) Pilot Study using B-mode ultrasound. Carotid artery intima-media thickness (CIMT), a known subclinical predictor of cardiovascular disease, also was examined in relation to brachial artery reactivity. A continuous scan was performed on the artery for 8 min (1 min of baseline, 4 min of cuff inflation at 40 mmHg greater than systolic pressure, 3 min after cuff release).

The sample for analysis (n = 78; 43 men, 35 women) consisted of active-duty police officers from a larger sample in the BCOPS pilot study. Means and standard deviations (SDs) stratified by gender were calculated, along with Pearson's correlations between brachial variables, and with CIMT. Arterial diameters (baseline, pre-cuff release, peak) were significantly different ( p < 0.001) between men and women. Peak arterial dilation occurred at 50.77 ± 21.97 sec (49.67 ± 20.22 cardiac cycles) after cuff deflation in men, and 44.66 ± 24.07 sec (44.57 ± 20.36 cardiac cycles) after cuff deflation in women. Mean common carotid artery IMT and mean maximum IMT of all carotid sites were significantly correlated ( p < 0.01) in men (r = 0.691) and women (r = 0.450). Brachial reactivity measures were inversely correlated with CIMT in women, and in contrast, positively correlated in men.

Can Fetuin-A Be a Marker for Insulin Resistance and Poor Glycemic Control in Children with Type 1 Diabetes Mellitus?

OBJECTIVE

Metabolic impairment in type 1 diabetes mellitus (T1DM) with poor glycemic control causes insulin resistance, non-alcoholic fatty liver disease (NAFLD), atherosclerosis, and increased carotid intima-media thickness (CIMT). Fetuin-A has a protective effect in cardiovascular disorders and is increased in hepatosteatosis. We aimed to investigate the reliability of fetuin-A levels in early detection of diabetic complications in children with T1DM and to identify a cut-off value that may show poor metabolic control.

METHODS

The study included 80 patients who had T1DM for at least 5 years and who had no chronic complications or an auto-immune disorder. Blood samples were drawn to measure hemoglobin A1c (HbA1c), biochemical parameters, and fetuin-A levels. Anthropometric parameters were also measured. Percent body fat was calculated. Hepatosteatosis and CIMT were assessed by sonography.

RESULTS

Mean age of the patients was 13.5 years. Grade 1 hepatosteatosis was detected in 10%. Patients were stratified into 2 groups based on presence of NAFLD. Fetuin-A level was increased in patients with NAFLD. We identified a fetuin-A cut-off value (514.28 ng/mL; sensitivity: 47.34; specificity: 96.72) that may predict NAFLD. HbA1c and total cholesterol levels were found to be higher in patients with fetuin-A levels above higher the cut-off value.

CONCLUSION

Fetuin-A is a reliable parameter in the prediction of complications and poor glycemic control in patients with T1DM.

Diagnostic potential of differentially expressed Homer1, IL-1β, and TNF-α in coronary artery disease

Increasing evidences suggest that inflammation plays an important role in the pathogenesis of coronary artery disease (CAD). Numerous inflammatory cytokines and related genes mediate adverse cardiovascular events in patients with CAD, such as interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and Homer in the present study. The study was carried out on 163 CAD patients at different stages and 68 controls. The gene expression of Homer1, Homer2, Homer3, IL-1β, and TNF-α in the peripheral blood leukocytes were measured by real-time polymerase chain reaction. The mRNA levels of Homer1, IL-1β, and TNF-α in CAD patients were significantly higher than those in the control group, but not Homer2 and Homer3. However, there was no considerable difference in the mRNA levels of Homer1, IL-1β, and TNF-α among AMI, UAP, and SAP three subgroups of CAD. The receiver operating characteristic (ROC) curves showed that Homer1 had a better diagnostic value for UAP patients compared with IL-1β and TNF-α. Like IL-1β and TNF-α, Homer1 may also be an important participant of atherosclerotic plaque development and eventually rupture. The results of the present study may provide an important basis for diagnosing CAD patients, and provide new therapeutic targets for CAD.

Is serum Interleukin-17 associated with early atherosclerosis in obese patients?

Atherosclerosis is a chronic inflammatory process of the vessel walls, and CD4+ T-cells are peculiar to both human and murine atherosclerotic lesions. There is a recent line of research favoring hypothetic allergic mechanisms in the genesis of atherosclerosis and, consequently, coronary artery disease (CAD), among which Interleukin (IL)-17 appears to be a key cytokine regulating local tissue inflammation. The objective was to add a piece of information on the role of IL-17 in the genesis of atherosclerosis. Eighty obese patients with normal liver enzyme levels but presenting with ultrasonographic evidence of NAFLD formed the population of this cross-sectional study. Anthropometric measures, data on excess adiposity, metabolic profile, serum concentrations of IL-17, eotaxin-3, IL-8, and CCL4/MIP1β, C-reactive protein, fibrinogen, ferritin, TNF-α, as well carotid intima-media thickness (IMT), a marker of atherosclerosis, and the main risk factors for CAD, such as blood pressure and smoking status, but also less determinant ones such as degree of NAFLD severity, Intramuscular Triglyceride storage and Resting Metabolic Rate were evaluated. Serum concentrations of Il-17 were detected as related to those of inflammatory cytokines, IL-6, IFN-γ and TNF-α. Furthermore, circulating levels of IL-17 were linked to those mirroring allergic process, IL-8, CCL4/MIP1β and eotaxin. Early atherosclerosis, evidenced as increased IMT, was not associated with circulating IL-17 levels. At multiple regression,IMT was predicted, other than by age, by the amount of the visceral adiposity, expressed as visceral adipose tissue at ultrasonography, and by serum eotaxin. In conclusion, a strong relationship was found between the IL-17-related chemokine eotaxin and IMT. The association found between the amount of visceral fat and circulating levels of eotaxin on the one hand, and IMT on the other, could reinforce the hypothesis that IL-17, released by the visceral adipose tissue, induces eotaxin secretion via the smooth muscle cells present in the atheromatosus vessels.

Carotid intima-media thickness is predicted by combined eotaxin levels and severity of hepatic steatosis at ultrasonography in obese patients with Nonalcoholic Fatty Liver Disease

BACKGROUND

Non-Alcoholic Fatty Liver Disease (NAFLD) is a distinct coronary artery disease (CAD) risk factor. The atherosclerotic process predisposing to CAD includes altered lipid profile and inflammatory processes. The available evidence suggests that increased circulating levels of eotaxin, an eosinophil chemoattractant cytokine implicated in allergic responses, are detected in the serum of patients with CAD. Relationships were sought between serum eotaxin on the one hand, and intima-media thickness--an early predictor of the atherosclerotic process, hepatic steatosis, arterial blood pressure values, as well as inflammation/immune markers and angiogenetic factors--on the other.

METHODS

Eighty obese patients with NAFLD, diagnosed at ultrasonography, without evident cytolysis, formed our study population. Anthropometric measures, metabolic profile, serum concentrations of interleukin-1β, C-reactive protein, interleukin-6, fibrinogen, ferritin, TNF-α, spleen size, vascular endothelial growth factor, platelet-derived growth factor-BB and heat shock protein-70 were evaluated.

RESULTS

Serum eotaxin concentrations were distinctly associated with TNF α, IL-6, IL-1β, VEGF and PDGF-BB levels but not with CRP, fibrinogen, heat shock protein-70 or spleen size. Among the metabolic and anthropometric parameters, a significant predictive power emerged when comparing eotaxin to insulin resistance, expressed as HOMA. NAFLD was distinctly associated with HOMA (P = 0.0005). Intima-media thickness was well predicted by both eotaxin levels and severity of NAFLD at ultrasonography, although no relation was detected between these last two variables.

DISCUSSION AND CONCLUSION

A role for insulin resistance in mediating the interplay between eotaxin and other inflammation/immune parameters could be evidenced in the induction/maintenance of atherosclerosis of obese patients with NAFLD.

Circulating levels of sirtuin 4, a potential marker of oxidative metabolism, related to coronary artery disease in obese patients suffering from NAFLD, with normal or slightly increased liver enzymes

The present study shows low circulating levels of SIRT4 in obese patients with nonalcoholic fatty liver disease mirroring its reduced mitochondrial expression in an attempt to increase the fat oxidative capacity and then the mitochondrial function in liver and in muscle. SIRT4 modulates the metabolism of free fatty acids reducing their high circulating levels but, unfortunately, increasing ROS production. Great concentration of free fatty acids, released by adipose tissue, coupled with oxidative stress, directly results in endothelial dysfunction, early atherosclerosis, and coronary artery disease risk factor.

Evaluation of subclinical atherosclerosis in Egyptian psoriatic patients

BACKGROUND

Psoriasis (Ps) is a common, relapsing, immune-mediated, inflammatory skin disorder of unknown etiology. Ps is not single organ disease confined to the skin but it is systematic inflammatory condition analogous to other inflammatory immune disorders which are known to have increased risk of heart disease. On other hand, inflammation plays also an important role in the pathogenesis of atherosclerosis. So, there is striking similarity between molecular and inflammatory pathway in Ps and atherosclerosis.

AIM OF THE WORK

Was to assess the presence of subclinical atherosclerosis in patients with Ps by using carotid ultrasonography.

PATIENTS AND METHODS

60 patients with Ps were enrolled in this study after exclusion of traditional cardiovascular risk factors and cardiovascular diseases (CVD). In addition, 20 age and gender matched healthy persons served as controls. Patients were classified according to Ps area and severity index (PASI) score into group I (20 mild patients), group II (20 moderate) and group III (20 severe). The average common carotid artery (CCA) intima media thickness (IMT), internal diameter (ID) and arterial wall mass index (AWMI) were measured using high resolution B- mode ultrasound.

RESULTS

Psoriatic patients showed statistically significant increase in CCA-IMT (P value 0.001), AWMI (P value 0.010) and significant decrease in ID (P value 0.001), as compared to controls.

CONCLUSION

Psoriasis patients could be suggested as a group with an increased atherosclerotic risk especially in older ages with longer duration of Ps. The carotid IMT, ID and AWMI can identify patients with subclinical atherosclerosis who need special follow up to reduce cardiovascular morbidity and mortality.

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

BACKGROUND

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

OBJECTIVE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSION

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

Clinical implications of skeletal muscle blood-oxygenation-level-dependent (BOLD) MRI

Blood-oxygenation-level-dependent (BOLD) contrast in magnetic resonance (MR) imaging of skeletal muscle mainly depends on changes of oxygen saturation in the microcirculation. In recent years, an increasing number of studies have evaluated the clinical relevance of skeletal muscle BOLD MR imaging in vascular diseases, such as peripheral arterial occlusive disease, diabetes mellitus, and chronic compartment syndrome. BOLD imaging combines the advantages of MR imaging, i.e., high spatial resolution, no exposure to ionizing radiation, with functional information of local microvascular perfusion. Due to intrinsic contrast provoked via changes in hemoglobin oxygen saturation, it is a safe and easy applicable procedure on standard whole-body MR devices. Therefore, BOLD MR imaging of skeletal muscle is a potential new diagnostic tool in the clinical evaluation of vascular, inflammatory, and muscular pathologies. Our review focuses on the current evidence concerning the use of BOLD MR imaging of skeletal muscle under pathological conditions and highlights ways for future clinical and scientific applications.

A comparison of 16 weeks of continuous vs intermittent exercise training in chronic heart failure patients

The authors compared the effects of continuous (CON) and intermittent (INT) exercise training programs on functional capacity, quality of life (QOL), and cardiac function in 23 congestive heart failure patients. Patients were randomized to CON exercise training (n=13; aged 66±7 years; peak oxygen consumption [VO(2)], 12.4±2.5 mL/kg/min; weight, 83±12 kg; left ventricular ejection fraction [LVEF], 29.5%±7.2%) or INT exercise training (n=10; aged 59±11 years; VO(2), 12.2±6.5 mL/kg/min; weight, 87±24 kg; LVEF 27%±7.9%). These groups completed 16 weeks of stationary cycling at 70% VO(2) thrice weekly for 30 minutes continuously or 60 minutes (60 seconds work:60 seconds rest) intermittently; both groups completed the same absolute volume of work. Three QOL questionnaire responses, VO(2), LVEF, and regional tissue Doppler were quantified. After exercise training, VO(2) increased by 13% in the CON group (P=.12) and significantly by 21% in the INT group (P=.03), although not significantly between the groups (P=.72). In the CON group, Minnesota Living With Heart Failure score improved at 16 weeks (P=.02), while in the INT group, Hare-Davis scores improved (P=.02). Cardiac volumes, resting and peak LVEF, contractile reserve, and tissue velocities were all unchanged from baseline. Intermittent exercise may improve functional capacity to a greater extent than continuous exercise. QOL changes were variable between groups.

Cardiac and vascular structure and function parameters do not improve with alternate nightly home hemodialysis: an interventional cohort study

BACKGROUND

Nightly extended hours hemodialysis may improve left ventricular hypertrophy and function and endothelial function but presents problems of sustainability and increased cost. The effect of alternate nightly home hemodialysis (NHD) on cardiovascular structure and function is not known.

METHODS

Sixty-three patients on standard hemodialysis (SHD: 3.5-6 hours/session, 3-5 sessions weekly) converted to NHD (6-10 hours/session overnight for 3-5 sessions weekly). 2Dimensional transthoracic echocardiography and ultrasound measures of brachial artery reactivity (BAR), carotid intima-media thickness (CIMT), total arterial compliance (TAC) and augmentation index (AIX) were performed post dialysis at baseline and 18-24 months following conversion to NHD. In 37 patients, indices of oxidative stress: plasma malonyldialdehyde (MDA) and anti-oxidant enzymes: catalase (CAT), glutathione peroxidase (GPX) and superoxide dismutase (SOD) activity and total antioxidant status (TAS) were measured at baseline, 3 and 6 months.

RESULTS

Left ventricular mass index (LVMI) remained stable. Despite significant derangement at baseline, there were no changes in diastolic function measures, CIMT, BAR and TAC. AIX increased. Conversion to NHD improved bone mineral metabolism parameters and blood pressure control. Interdialytic weight gains increased. No definite improvements in measures of oxidative stress were demonstrated.

CONCLUSIONS

Despite improvement in uremic toxin levels and some cardiovascular risk factors, conversion to an alternate nightly NHD regimen did not improve cardiovascular structure and function. Continuing suboptimal control of uremic toxins and interdialytic weight gains may be a possible explanation. This study adds to the increasing uncertainty about the nature of improvement in cardiovascular parameters with conversion to intensive hemodialysis regimens. Future randomized controlled trials will be important to determine whether increases in dialysis session duration, frequency or both are most beneficial for improving cardiovascular disease whilst minimizing costs and the impact of dialysis on quality of life.

Peripheral microvascular response to muscle contraction is unaltered by early diabetes but decreases with age

Long-term or untreated diabetes leads to micro- and macrovascular complications. However, there are few tests to evaluate microvascular function. A postcontraction blood oxygen level-dependent (BOLD) magnetic resonance imaging (MRI) technique was exploited to measure peripheral microvascular function in diabetics and healthy controls matched with respect to age, body mass index, and physical activity. Postcontraction BOLD microvascular response was measured following 1-s maximal isometric ankle dorsiflexion in individuals with diabetes mellitus type I [DMI, n = 15, age 33 ± 3 yr (means ± SE), median diabetes duration = 5.5 yr] and type II (DMII, n = 16, age 45 ± 2 yr, median duration = 2.4 yr); responses were compared with controls (CONI and CONII). Peripheral macrovascular function of the popliteal and tibial arteries was assessed during exercise hyperemia with phase contrast magnetic resonance angiography following repetitive exercise. There were no group differences as a result of diabetes in peripheral microvascular function (peak BOLD response: DMI = 2.04 ± 0.38% vs. CONI = 2.08 ± 0.48%; DMII = 0.93 ± 0.24% vs. CONII = 1.13 ± 0.24%; mean ± SE), but the BOLD response was significantly influenced by age (partial r = -0.384, P = 0.003), supporting its sensitivity as a measure of microvascular function. Eleven individuals had no microvascular BOLD response, including three diabetics with neuropathy and four controls with a family history of diabetes. There were no differences in peripheral macrovascular function between groups when assessing exercise hyperemia or the pulsitility and resistive indexes. Although the BOLD microvascular response was not impaired in early diabetes, these results encourage further investigation of muscle BOLD as it relates to peripheral microvascular health.

Multimodality vascular imaging in CKD: divergence of risk between measured parameters

BACKGROUND

High cardiovascular risk in chronic kidney disease (CKD) patients appears only partly attributable to atherosclerosis, with much of the remaining risk being ascribed to other vasculature abnormalities, including endothelial dysfunction, arterial stiffness and vascular calcification (VC). To date, these factors have been primarily studied in isolation or in dialysis patients. This study performed a global vascular assessment in moderate CKD and assessed the relationships with both traditional and novel risk factors.

METHODS

This was a prospective cross-sectional analysis of 120 patients (age 60 ± 10 years; estimated glomerular filtration rate 25-60 mL/min/1.73m(2)). Demographic, clinical and biochemical characterization was performed. VC was characterized by lateral lumbar radiograph; arterial stiffness by aortic pulse-wave velocity (PWV); atheroma burden by carotid intima-media thickness (cIMT) and endothelial function by flow-mediated dilation (FMD) of the brachial artery.

RESULTS

VC was highly prevalent (74%), and FMD generally poor (FMDΔ 3.3 ± 3.3%). There were significant correlations between all vascular parameters; although these were predominantly explained by age. cIMT was independently associated with classical risks and also PWV (adjusted standardized β = 0.31, P = 0.001). However, traditional risks showed almost no independent associations with other vascular measurements. In contrast, serum phosphate and 1,25-dihydroxyvitamin D (1,25-OHD) correlated with PWV and the presence of VC, respectively. After adjustment, every 1 pg/mL increase in 1,25-OHD was related to a 3% reduction in the chance of VC (odds ratio 0.97; 95% confidence interval 0.94-1.00, P = 0.03). Medication use, HOMA-IR and C-reactive protein did not correlate with any of the vascular measures.

CONCLUSIONS

This study demonstrates extensive vascular disease across multimodality imaging in moderate CKD. Atherosclerotic burden correlated with traditional risks and PWV, while higher 1,25-OHD was associated with less VC. The lack of association between renal function and imaging indices raises the possibility of a threshold, rather than graded uraemic effect on vascular health that warrants further exploration.

Two weeks taurine supplementation reverses endothelial dysfunction in young male type 1 diabetics

Type 1 diabetics have a well-recognised risk of accelerated cardiovascular disease. Even in the absence of clinical signs there are detectable abnormalities of conduit vessel function. Our group has previously reported reversal of endothelial dysfunction in diabetics with pravastatin. In young asymptomatic smokers, taurine supplementation has a beneficial impact on macrovascular function, assessed by FMD, and shows an up-regulation of nitric oxide from monocyte-endothelial cell interactions. We hypothesise that taurine supplementation reverses early endothelial abnormalities in young male type 1 diabetics, as assessed by applanation tonometry, brachial artery ultrasound and laser Doppler fluximetry. Asymptomatic, male diabetics (n=9) were scanned prior to treatment and then randomised in a double-blind cross-over fashion to receive either 2 weeks placebo or taurine. Control patients (n=10) underwent a baseline scan. Assessed diabetics had detectable, statistically significant abnormalities when compared with controls, in both arterial stiffness (augmentation index) and brachial artery reactivity (FMD). Both of these parameters were returned to control levels with 2 weeks taurine supplementation. In conclusion, 2 weeks taurine supplementation reverses early, detectable conduit vessel abnormalities in young male diabetics. This may have important implications in the long-term treatment of diabetic patients and their subsequent progression towards atherosclerotic disease.

Vascular dysfunction in glycogen storage disease type I

OBJECTIVE

To determine cardiovascular disease risk in a larger cohort of patients with glycogen storage disease (GSD) I through the use of noninvasive measures of arterial function and anatomy.

STUDY DESIGN

Carotid intima media thickness (IMT), radial artery tonometry, and brachial artery reactivity were performed in 28 patients with GSD I (13F/15M, mean age 23 years) and 23 control subjects (19F/4M, mean age 23 years).

RESULTS

The primary outcome measure, mean left distal IMT was greater in the GSD cohort (0.500+/-0.055 mm) than in the control group (0.457+/-0.039 mm) (P= .002, adjusted for age, sex, and body mass index). Mean augmentation index measured by radial artery tonometry was higher in the GSD cohort (16.4%+/-14.0%) than in the control group (2.4%+/-8.7%) (P< .001). No significant difference was observed between mean brachial artery reactivity in the GSD cohort (6.3%+/-4.9% change) versus control subjects (6.6%+/-5.1% change) (P= .46).

CONCLUSIONS

GSD I is associated with arterial dysfunction evident by increased IMT and augmentation index. Patients with GSD I may be at increased risk for cardiovascular disease.

The use of surrogate vascular markers in youth at risk for premature cardiovascular disease

Premature cardiovascular disease (CVD) begins in youth--a crucial period when modification of the disease may have the greatest impact. Failure to diagnose preclinical CVD at this stage misses a major opportunity to prevent the long-term consequences of this disease. An array of surrogate vascular markers (SVMs) are now available that can determine the extent of preclinical vascular injury in the pediatric population. These SVMs include flow-mediated vasodilatation, carotid intima media thickness, arterial stiffness, and biomarkers including high sensitivity C-reactive protein, cell adhesion molecules and methylarginines. We believe that the use of these SVMs will help to develop a better understanding of early pathological vascular changes in youth, facilitate earlier diagnosis of preclinical atherosclerosis and provide an objective measure of the vascular effects of any therapeutic intervention aimed at risk factor modification. Ultimately, our future health will depend on carefully balancing the benefits of early diagnosis and treatment in high-risk youth with the long-term risk of CVD. The application of SVMs in the pediatric population will help us achieve this balance.

Significance of heterogenity in endothel-dependent vasodilatation occurrence in healthy individuals with or without coronary risk factors

Background/Aim. Brachial artery flow-mediated dilation (FMD) is extensively used for non-invasive assessment of endothelial function. Traditionally, FMD is calculated as a percent change of arterial diameter from the baseline value at an arbitrary time point after cuff deflation (usually 60 seconds). Considerable individual differences in brachial artery temporal response to hyperemic stimulus have been observed, potentially influenced by the presence of atherosclerotic risk factors (RF). The importance of such differences for the evaluation of endothelial function has not been well established. The aim of the stady was to determine the time course of maximal brachial artery endothelium- dependent dilation in healthy adults with and without RF, to explore the correlation of RF with brachial artery temporal response and to evaluate the importance of individual differences in temporal response for the assessment of endothelial function. Methods. A total of 115 healthy volunteers were included in the study. Out of them, 58 had no RF (26 men, mean age 44 ? 14 years) and 57 had at least one RF (29 men, mean age 45 ? 14 years). High-resolution color Doppler vascular ultrasound was used for brachial artery imaging. To determine maximal arterial diameter after cuff deflation and the time-point of maximal vasodilation off-line sequential measurements were performed every 10 seconds from 0 to 240 seconds after cuff release. True maximal FMD value was calculated as a percent change of the true maximal diameter from the baseline, and compared with FMD value calculated assuming that every participant reached maximal dilation at 60 seconds post cuff deflation (FMD60). Correlation of different RF with brachial artery temporal response was assessed. Results. A maximal brachial artery endothelium-dependent vasodilation occurred from 30-120 seconds after cuff release, and the mean time of endothelium-dependent dilation was 68 ? 20 seconds. Individuals without RF had faster endothelium-dependent dilation (mean time 62 ? 17 seconds), and a shorter timespan (30 to 100 seconds), than participants with RF (mean time 75 ? 21 seconds, time-span 40 to 120 seconds) (p < 0.001). Time when the maximal endotheliumdependent dilation occurred was independently associated with age, serum lipid fractions (total cholesterol, LDL and HDL cholesterol), smoking, physical activity and C-reactive protein. True maximal FMD value in the whole group (6.7 ? 3.0%) was significantly higher (p < 0.001) than FMD60 (5.2 ? 3.5%). The same results were demonstrated for individuals with RF (4.9 ? 1.7% vs 3.1 ? 2.3%, p < 0.001) and without RF (8.4 ? 2.9% vs 7.2 ? 3.2%, p < 0.05). Conclusion. The temporal response of endothelium- dependent dilation is influenced by the presence of coronary FR and individually heterogeneous. When calculated according to the commonly used approach, i.e. 60 seconds after cuff deflation, FMD is significantly lower than the true maximal FMD. The routinely used measurement time-points for FMD assessment may not be adequate for the detection of true peak vasodilation in individual persons. More precise evaluation of endothelial function can be achieved with sequential measurement of arterial diameter after hyperemic stimulus.

Increased carotid artery intima-media thickness and impaired endothelial function in psoriasis

BACKGROUND

Psoriasis is associated with an increased risk of atherosclerosis. This study compared subclinical atherosclerosis of the carotid and brachial arteries in psoriasis vulgaris patients and healthy controls using high-resolution ultrasonography.

METHODS

We studied 43 psoriasis patients and 43 healthy controls matched for age and sex. Flow-mediated dilatation (FMD) and nitroglycerin-induced dilatation (NTD) of the brachial artery and intima-media thickness (IMT) of the common carotid arteries (CCA) were measured ultrasonographically. Diabetes mellitus, hypertension, renal failure, a history of cardiovascular or cerebrovascular disease were exclusion criteria. Subjects who were receiving lipid-lowering therapy, antihypertensive or anti-aggregant drugs, nitrates or long-term systemic steroids were also excluded.

RESULTS

The mean IMT values of the right, left and averaged CCA of the psoriasis patients were significantly higher, compared with the controls (0.607+/-0.144 mm vs. 0.532+/-0.101 mm, 0.611+/-0.157 mm vs. 0.521+/-0.117 mm, and 0.609+/-0.146 mm vs. 0.526+/-0.104 mm; P=0.006, P=0.003 and P=0.003, respectively). The mean FMD and NTD values of the psoriasis patients were significantly lower, compared with the controls (13.36+/-6.39 mm vs. 19.60+/-11.23 mm and 21.08+/-8.38 mm vs. 26.85+/-12.38 mm; P=0.002 and P=0.013, respectively). Multiple linear regression analysis revealed a significant association between psoriasis and the IMT, FMD and NTD. Moreover, the FMD in psoriasis patients was associated with disease duration.

CONCLUSION

Psoriasis patients had impaired endothelial function and thicker IMT of the CCA, compared with the healthy control subjects. The presence of psoriasis was an independent risk factor for subclinical atherosclerosis.

Correlates of preclinical cardiovascular disease in Indigenous and Non-Indigenous Australians: a case control study

Background

The high frequency of premature death from cardiovascular disease in indigenous Australians is often attributed to the high prevalence of risk factors, especially type II diabetes mellitus (DM). We evaluated the relationship of ethnicity to atherosclerotic burden, as evidenced by carotid intima-media thickness (IMT), independent of risk factor status.

Methods

We studied 227 subjects (147 men; 50 ± 13 y): 119 indigenous subjects with (IDM, n = 54), and without DM (InDM, n = 65), 108 Caucasian subjects with (CDM, n = 52), and without DM (CnDM, n = 56). IMT was measured according to standard methods and compared with clinical data and cardiovascular risk factors.

Results

In subjects both with and without DM, IMT was significantly greater in indigenous subjects. There were no significant differences in gender, body mass index (BMI), systolic blood pressure (SBP), or diastolic blood pressure (DBP) between any of the groups, and subjects with DM showed no difference in plasma HbA1c. Cardiovascular risk factors were significantly more prevalent in indigenous subjects. Nonetheless, ethnicity (β = -0.34; p < 0.0001), age (β = 0.48; p < 0.0001), and smoking (β = 0.13; p < 0.007) were independent predictors of IMT in multiple linear regression models.

Conclusion

Ethnicity appears to be an independent correlate of preclinical cardiovascular disease, even after correction for the high prevalence of cardiovascular risk factors in indigenous Australians. Standard approaches to control currently known risk factors are vital to reduce the burden of cardiovascular disease, but in themselves may be insufficient to fully address the high prevalence in this population.

Impaired systemic endothelial function in patients with pseudoexfoliation syndrome

Pseudoexfoliation syndrome (PEX) is the most common clinical precursor of open-angle glaucoma. Recent studies have shown that pseudoexfoliative material is widely distributed throughout the body, including blood vessels. The aim of our study was to evaluate endothelial function in the brachial artery of patients with pseudoexfoliation syndrome. We prospectively examined 23 patients with PEX (mean age, 70 +/- 8 years) and 20 healthy age- and sex-matched individuals (mean age, 68 +/- 9 years) as a control group. Brachial artery endothelial function was assessed by vascular response to reactive hyperemia (flow-mediated dilation (FMD) and sublingual nitroglycerin (NTG-mediated dilation) using high-resolution ultrasound. Flow-mediated and NTG-induced dilation were expressed as the percent change in diameter after reactive hyperemia and after NTG administration relative to the baseline value, respectively. Patients with cardiovascular disease and other conditions associated with endothelial dysfunction were excluded. When compared with controls, patients with PEX had significantly lower flow-mediated dilation (4.5 +/- 2.8 versus 8.2 +/- 3.7, P = 0.01) and NTG-mediated dilation (10.9 +/- 3.1 versus 15.8 +/- 3.8, P = 0.0001). Flow-mediated dilation and NTG-mediated dilation were similar in PEX patients with glaucoma (n = 11) and without glaucoma (n = 12). Flow-mediated and NTG-mediated dilation did not correlate with any measured parameter in any patient or control subject. The findings indicate that systemic endothelial function is impaired in PEX syndrome patients.

Flow-mediated vasodilation and carotid intima-media thickness in systemic sclerosis

Increased evidence suggests an accelerated macrovascular disease in systemic sclerosis (SSc). Brachial artery flow-mediated vasodilation (FMD) and carotid intima-media thickness (IMT) are two indicators of subclinic cardiovascular disease and are frequently used as surrogate measures of subclinic atherosclerosis. The aim of this study was to evaluate macrovascular involvement in SSc. We studied 35 SSc patients (6 males and 29 females; 11 with diffuse and 24 with limited disease) and 20 healthy controls. Brachial artery FMD was assessed by method described by Celermajer in all patients and 13 control subjects. IMT was measured using high-resolution B-mode ultrasonography in patients and controls. Traditional risk factors for atherosclerosis (hypertension, dyslipidemia, and smoke) were also assessed. FMD was significantly impaired (3.41% +/- 4.56% versus 7.66% +/- 4.24%; P < 0.037) and IMT was significantly elevated compared with healthy controls (0.93 +/- 0.29 mm versus 0.77 +/- 0.13 mm; P < 0.005). FMD was not significantly different in SSc with increased IMT compared with those with normal IMT). No correlation was found between risk factors for atherosclerosis and the impairment of FMD or IMT in SSc patients. The impairment of endothelial function and structural changes of large vessels are evident in SSc, but do not seem associated with traditional risk factors for atherosclerosis. Prospective studies including also clinical outcomes are needed to assess the features and significance of macrovacular involvement in SSc.

Identification of brachial artery characteristic using a cuff for noninvasive detection of coronary artery disease

How could a cuff cause a peripheral artery to enter its resonance mode? How could the arterial oscillations be used to evaluate the arteries and to diagnose coronary artery disease (CAD)? This paper answers. A conceptual model representing the role of cuff-artery connection to produce a step-like (sharpened) pressure stimulator is also introduced. The arterial dynamic response is recorded noninvasively in the form of arterio- oscillo-gram (AOG) via an accelerometer. Only, the big oscillatory parts of AOG are used to assess the arterial structure. Due to CAD correlation with peripheral arteriosclerosis, the CAD can also be diagnosed by analyzing AOG peaks. For every person of 51 samples including 22 CAD, 22 normal and 7 heart murmur (HM) patients, the mean of five largest peak durations is calculated. The more severity of CAD causes the less duration time. Hence, simply, by defining a threshold of 9.25 ms, two CAD and non-CAD groups were classified with accuracies of 77% (17/22), and 82% (17/22 for normal, and 7/7 for HM), respectively. This simple noninvasive method mainly aims the vascular characteristics evaluation, thus it does not have the usual limitations of other CAD detection methods.

Menopause, estrogens, and endothelial dysfunction: current concepts

Menopause is defined as the permanent cessation of menses. Cardiovascular disease is the leading cause of death among postmenopausal women in developed countries. The disparity between the incidence of cardiovascular disease among women in pre- and postmenopause has been ascribed to the actions of endogenous estrogen on the cardiovascular system and, particularly, on the vascular endothelium. The endothelium plays an important role in cardiovascular homeostasis, either through the vascular tonus and its regulation, or through coagulation and the inflammatory response. Endothelial dysfunction is implicated in the genesis of atherosclerosis and other chronic disorders, such as diabetes mellitus and hypertension. The pharmacological use of estrogen exerts influence on the circulating levels of markers of vascular tonus, and inflammation, as well as prothrombotic, and fibrinolytic markers, but the impact of these changes on the atherosclerotic disease is still uncertain.

A new technique for assessing arterial pressure wave forms and central pressure with tissue Doppler

Background

Non-invasive assessment of arterial pressure wave forms using applanation tonometry of the radial or carotid arteries can be technically challenging and has not found wide clinical application. 2D imaging of the common carotid arteries is routinely used and we sought to determine whether arterial waveform measurements could be derived from tissue Doppler imaging (TDI) of the carotid artery.

Methods

We studied 91 subjects (52 men, age 52 ± 14 years) with and without cardiovascular disease. Tonometry was performed on the carotid artery simultaneously with pulsed wave Doppler of the LVOT and acquired digitally. Longitudinal 2D images of the common carotid artery with and without TDI were also acquired digitally and both TDI and tonometry were calibrated using mean and diastolic cuff pressure and analysed off line.

Results

Correlation between central pressure by TDI and tonometry was excellent for maximum pressure (r = 0.97, p < 0.0001). The mean differences between central pressures derived by TDI and tonometry were minimal (systolic 5.36 ± 5.5 mmHg; diastolic 1.2 ± 1.2 mmHg).

Conclusion

Imaging of the common carotid artery motion with tissue Doppler may permit acquisition of a waveform analogous to that from tonometry. This method may simplify estimation of central arterial pressure and calculation of total arterial compliance.

Vascular endothelial dysfunction in patients with mild Obstructive Sleep Apnea Syndrome

BACKGROUND

We investigated endothelial dysfunction, an early manifestation of atherosclerosis, in patients with mild obstructive sleep apnea syndrome (OSAS) (5/h < AHI < 15/h).

PATIENTS AND METHODS

Endothelium-dependent and -independent vasodilatory function was tested in 10 patients with mild OSAS, 12 healthy controls and 20 subjects with moderate to severe OSAS using the hand vein compliance technique.

RESULTS

Maximum endothelium-dependent vasodilation to bradykinin (Emax) was significantly blunted in patients with mild OSAS (68.6 +/- 30.2 %) compared to healthy controls (94.8 +/- 9.5 %; p < 0.05; moderate to severe OSAS: 57.1 +/- 23.4 %; p = 0.33). Mean endothelium-independent venodilation was not altered. After 160.7 +/- 82.2 nights of CPAP therapy, mean Emax was significantly improved to 90.8 +/- 23.8 % (p < 0.01 vs. baseline; p = 0.7 vs. healthy controls) in 7 patients with mild OSAS.

CONCLUSIONS

Systemic endothelium-dependent venodilation is markedly reduced in subjects with mild OSAS, which may imply adverse cardiovascular consequences. CPAP-treatment leads to a sustained restoration of endothelial dysfunction in these patients and is thus highly recommended.

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.

Impact of obesity in intima media thickness of carotid arteries

OBJECTIVE

To explore differences in intima media thickness (IMT) of the carotid arteries induced by differences in BMI.

RESEARCH METHODS AND PROCEDURES

Data from 3173 consecutive subjects, who were referred to our Hypertension Center from 1998 to 2004, were reviewed. Criteria for patients to be considered for further analysis included no past or concurrent antihypertensive medication, no concurrent medication with the potential to raise blood pressure (BP) (e.g., prednisone), and no clinical signs or laboratory evidence of secondary causes of hypertension. Our population was divided into four groups according to NIH criteria for obesity: underweight, normal weight, overweight, and obese. BMI, mean IMT of internal carotid arteries, and 24-hour BP values were available for all subjects. Five hundred thirty six subjects of the four groups, matched for age, gender, and mean 24-hour BP values, were included in the analysis.

RESULTS

Mean IMT of internal carotid arteries was increased with increasing BMI. Mean IMT was significantly higher in obese subjects compared with normal-weight (p < 0.01) and underweight (p < 0.001) subjects. Mean IMT was significantly higher in overweight subjects compared with normal-weight ones (p < 0.05). Furthermore, multivariate regression analysis in obese subjects revealed that fasting serum glucose was independently associated with IMT.

DISCUSSION

Obesity may be an important factor for carotid atherosclerosis, and at least some of the effects of obesity are independent of the BP levels. Fasting serum glucose levels in obese subjects may play an important role in carotid atherosclerosis.

A proinflammatory state is detectable in obese children and is accompanied by functional and morphological vascular changes

BACKGROUND

Obesity is generally accepted as a risk factor for premature atherosclerosis. Subclinical inflammation as quantified by blood levels of C-reactive protein (CRP) contributes to the development and progression of atherosclerosis. We hypothesized that inflammation in obese children is related to functional and early morphological vascular changes.

METHODS AND RESULTS

Blood levels of high sensitivity (hs) CRP, hsIL-6, the soluble intercellular adhesion molecule1 (ICAM-1), vascular cell adhesion molecule (VCAM)-1, and E-selectin were measured in 145 severely obese (body mass index [BMI], 32.2+/-5.8 kg/m2) and 54 lean (BMI, 18.9+/-3.2 kg/m2) children 12+/-4 years old. Flow-mediated dilation (FMD) of the brachial artery and carotid intima-media thickness (IMT) measured by high-resolution ultrasound as markers of early vascular changes were assessed in 92 (77 obese and 15 lean) and 59 (50 obese and 9 lean) children, respectively. Obese children had significantly higher levels of hsCRP, hsIL-6, and E-selectin than healthy controls (4.1+/-4.8 versus 0.9+/-1.5 mg/L, P<0.001 for hsCRP; 1.99+/-1.30 versus 1.42+/-1.01 pg/mL, P=0.05 for hsIL-6; and 78+/-38 versus 59+/-29 ng/mL, P=0.01 for E-selectin). There were no differences in the levels of ICAM-1 and VCAM-1 between groups. Obese children had lower peak FMD response (7.70+/-6.14 versus 11.06+/-3.07%, P=0.006) and increased IMT (0.37+/-0.04 versus 0.34+/-0.03 mm, P=0.03) compared with controls. Morbidly obese children (n=14, BMI 44.1+/-3.9 kg/m2) had highest levels of hsCRP (8.7+/-0.7 mg/L), hsIL-6 (3.32+/-1.1 pg/mL), and E-selectin (83+/-40 ng/mL).

CONCLUSIONS

A proinflammatory state is detectable in obese children, which is accompanied by impaired vascular endothelial function and early structural changes of arteries, even in young subjects at risk. It remains to be determined whether high hsCRP in obese children predicts cardiovascular events.

Determinants of carotid plaque occurrence. A long-term prospective population study: the San Daniele Project

BACKGROUND

Increased carotid intima media thickness (CIMT) is frequently associated with established modifiable and non-modifiable cardiovascular risk factors, and is thought to be an independent predictor of ischemic cerebrovascular and cardiac events. The presence of carotid plaque is considered an established feature of atherosclerosis. There exist few longitudinal data on the predictive role of CIMT in the occurrence of carotid plaque.

METHODS

We restudied the survivors of a cohort of the San Daniele Project, a large randomized general population study, investigated in 1990 regarding the prevalence and determinants of carotid atherosclerosis. Using ultrasonography, we determined in 1,193 subjects (548 men and 645 women), the common carotid IMT and the presence of non-stenotic and stenotic plaque.

RESULTS

In 795 subjects without plaques or previous ischemic events at baseline, we found in multivariate analysis that CIMT > or =1 mm, age, hypertension and history of smoking are significant predictive elements of the occurrence of a new carotid plaque. The incremental probability of plaque occurrence is greater in midlife. CIMT and age are the most predictive risk factors with ORs of 3.66 (95% CI 1.4-9.4) and 3.02 (95% CI 2.4-3.7), respectively. The ORs for hypertension and smoking account for 1.5 (95% CI 1.1-3.4) and 1.7 (95% CI 1.1-2.8), respectively.

CONCLUSIONS

Age, hypertension, history of smoking and B-mode detection of CIMT increases in subjects without carotid atherosclerosis and free of previous vascular events predict the occurrence of carotid atherosclerotic plaque.

Prediction of major adverse cardiovascular events by age-normalized carotid intimal medial thickness

BACKGROUND

Increases in carotid intimal medial thickness (IMT), as measured by noninvasive ultrasonography, have been associated with increased risk of myocardial infarction and stroke, particularly in adults 65 years of age or older. We investigated the value of age-normalized carotid IMT measurements in predicting major adverse cardiovascular events in a population of patients referred for carotid IMT measurement.

METHODS

Since 1995, 727 patients had carotid IMT measured at the University of Virginia's Preventive Cardiology practice. We successfully contacted 706 of these patients to determine clinical outcomes; 21 patients were lost to follow-up. The 706 patients were entered into a database, age-specific quartiles of carotid thickness developed, and odds ratios were calculated with logistic regression.

RESULTS

Over a mean follow-up period of 4.78 years (range, 2.0-9.3 years), 20 patients had major adverse cardiovascular events: seven patients had myocardial infarctions; seven required revascularization; and six had a stroke or transient ischemic attack. The incidence of events directly correlated with age-normalized measurements of carotid bulb and internal carotid IMT. The highest quartile of carotid bulb IMT demonstrated an odds ratio for all events of 5.8 (95% confidence interval, 1.3-26.6; P = 0.023) when compared to the quartile with the lowest thickness (P = 0.007 for trend). A similar trend for quartiles of internal carotid IMT was also observed (P = 0.03). Common carotid IMT did not significantly predict events.

CONCLUSIONS

Age-normalized measurement of carotid bulb and internal carotid IMT may be helpful in determining which individuals would most benefit from aggressive risk-factor modification.

Decreased heart rate variability may predict the progression of carotid atherosclerosis in type 2 diabetes

Heart rate variability (HRV), a measure of autonomic function, can predict survival outcomes. Cardiovascular disease is a known complication of diabetes, and we aimed to determine if autonomic dysfunction was associated with carotid artery atherosclerotic plaques in type 2 diabetic patients. We assessed frequency domain HRV from power spectral analysis of 24 h Holter ECG recordings, expiration/inspiration (E/I) ratio during deep breathing, acceleration index (AI) of R-R interval in response to head-up tilt, and the degree of carotid artery atherosclerosis in 61 type-2 diabetic patients (39 males, 45-69 years). Studies were carried out 5-6 years after diagnosis (baseline) and repeated 8 years after diagnosis (follow-up). At baseline, patients diagnosed with autonomic neuropathy, with abnormal E/I ratio and abnormal AI measurements, had decreased low frequency (LF) HRV. Baseline E/I ratio correlated with day (r = 0.34; P < 0.001) and night-time (r = 0.44; P < 0.001) LF power. Night-time HRV did not differ in patient with and without autonomic neuropathy. Reduced common carotid artery diameter and atherosclerotic intima-media thickness (IMT) both correlated with HRV at baseline. At follow-up, all HRV variables decreased significantly. Furthermore, patients with lower LF power at baseline, had a larger increase in the thickness of the carotid bulb intima-media at follow-up. Our results show that LF HRV power is associated with the extent and progression of carotid atherosclerosis in type 2 diabetes. A low LF HRV may predict the progression of atherosclerosis in these patients.

Inflammation, complement activation and endothelial function in stable and unstable coronary artery disease

BACKGROUND

Endothelial dysfunction plays an important role in the pathogenesis of coronary artery disease (CAD). Apart from traditional risk factors complement activation and inflammation may trigger and sustain endothelial dysfunction. We sought to assess the association between endothelial function, high sensitivity C-reactive protein (hs-CRP) and markers of complement activation in patients with either stable or unstable coronary artery disease.

METHODS

We prospectively recruited 78 patients, 35 patients with stable angina pectoris (SAP) and 43 patients with unstable angina pectoris (UAP). Endothelial function was assessed as brachial artery reactivity (BAR). Hs-CRP, C3a, C5a and C1-Inhibitor (C1 inh.) were measured enzymatically.

RESULTS

Patients with UAP showed higher median levels of hs-CRP and C3a compared to patients with SAP, while BAR was not significantly different between patient groups. In UAP patients, hs-CRP was significantly correlated with cholesterol (r=0.27, p<0.02), C3a (r=0.32, p<0.001) and C1 INH.(r=0.41, p<0.003), but not with flow mediated dilatation (r=0.09, P=0.41). Hs-CRP and C1 INH.were found to be independent predictors of UAP in a backward stepwise logistic regression model.

CONCLUSIONS

We conclude that both hs-CRP, a marker of inflammation and C3a, a marker of complement activation are elevated in patients with UAP, but not in patients with SAP.

Free fatty acids are associated with obesity, insulin resistance, and atherosclerosis in renal transplant recipients

BACKGROUND

Insulin resistance (IR) may be implicated in the pathogenesis of atherosclerosis in renal transplant recipients (RTRs) and be contributed to, in part, by free fatty acids (FFAs), produced in excess in centrally obese individuals. The aim of this study was to determine the prevalence of IR and the relationships between FFAs, central obesity, and atherosclerosis in a cohort of prevalent RTRs.

METHODS

Observational data were collected on 85 RTRs (mean age 54 years; 49% male, 87% Caucasian). Fasting serum was analyzed for FFAs, glucose, and insulin; IR was calculated using the homeostasis model assessment (HOMA-IR) score. Vascular structure was assessed by carotid intima-media thickness (IMT) measurement. Linear regression analyses were performed to determine the factors associated with IR and atherosclerosis.

RESULTS

IR occurred in 75% of RTRs, and FFA levels were independently associated with its occurrence (beta: -0.55, 95% CI: -1.02 to -0.07, P = 0.02). Other variables independently associated with IR were male sex, body mass index, central obesity, diabetes, systolic blood pressure and corticosteroid use. There was a significant correlation between FFA levels and IMT (r = 0.3, P=0.01). On multivariate analysis, IMT correlated with elevated FFA (beta: 0.07, 95% CI: 0.02-0.12, P = 0.007), diabetes mellitus (P = 0.05), older age (P < 0.002), and a body mass index >25 kg/m (P = 0.002).

CONCLUSIONS

FFAs are associated with the development of IR and may be involved in the pathogenesis of atherosclerosis in RTRs. Additional studies are required to explore these associations further before considering whether an interventional trial aimed at lowering FFA would be a worthwhile undertaking.

Screening for coronary artery disease in patients with diabetes: a Bayesian strategy of clinical risk evaluation and exercise echocardiography

OBJECTIVE

Screening for coronary artery disease is constrained by its low prevalence in unselected patients. We compared the ability of clinical scores to identify a high-risk group with diabetes mellitus and investigated a Bayesian strategy by combination with exercise echocardiography (ExE).

METHODS

The Framingham risk score (FRS), a score based on the American Diabetes Association (ADA) screening guidelines, the United Kingdom Prospective Diabetes Study (UKPDS) risk engine, and a disease-specific diabetic cardiac risk score (DCRS) were calculated in 199 asymptomatic patients with type 2 diabetes mellitus undergoing ExE. The frequency of abnormal ExE and the proportion of these with coronary stenoses were sought in groups designated as high risk on the basis of optimal cutoffs for each score. All patients were followed up for 1 year.

RESULTS

High risk was identified in fewer patients with the DCRS (27%) than FRS (38%, P = .02), ADA (41%, P = .004), and UKPDS (43%, P = .001). Exercise echocardiography was positive in 27 (14%); 11 of 23 proceeding to angiography showed significant stenoses. Areas under the receiver operator characteristic curves for prediction of a positive ExE were similar for DCRS, UKPDS, and FRS but less for ADA (P = .04). Positive ExE was uncommon in low-risk patients (8%-11%) and most were false positives (58%-80%). Cardiovascular events (n = 9) were more likely in the high-risk compared with the low-risk UKPDS (9% vs 2%, P = .03) and DCRS (12% vs 2%, P = .01).

CONCLUSION

Combination of the UKPDS or DCRS with ExE may optimize detection of coronary artery disease and cardiac events in asymptomatic patients, while minimizing the numbers of ExE and false-positive rate.

Impaired endothelial function in patients with ankylosing spondylitis

OBJECTIVE

In recent years, accelerated atherosclerosis and increased risk of cardiovascular events have been described in patients with rheumatic disease, particularly for rheumatoid arthritis and systemic lupus erythematosus. However, the link between inflammation, atherosclerosis and ankylosing spondylitis is controversial. We evaluated the degree of atherosclerosis and endothelial function of ankylosing spondylitis patients ultrasonographically.

METHODS

Fifty-four patients with ankylosing spondylitis (37 +/- 11 yr, 29 males, 25 females) and 31 healthy controls (35 +/- 9 yr, 16 males, 15 females) were consecutively enrolled in the study. Serum lipids, creatinine, glucose, and acute-phase proteins were assessed. The Bath Ankylosing Spondylitis Metrology Index (BASMI), Bath Ankylosing Spondylitis Functional Index (BASFI) and Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) were also evaluated. Flow-mediated dilatation and endothelium-independent dilatation of the brachial artery and intima-media thickness of the common carotid artery were measured sonographically.

RESULTS

Left, right and averaged intima-media thickness of the common carotid artery did not show a statistically significant difference between the ankylosing spondylitis and control groups. However, flow-mediated dilatation was significantly lower in the ankylosing spondylitis patients (14.1 +/- 6.7 vs 17.6 +/- 8%; P = 0.03). Likewise, nitroglycerin-induced dilatation was lower in the patient group, but the difference was not significant (16.4 +/- 6.8 vs 19.8 +/- 10%; P = 0.07). No correlation was detected between flow-mediated dilatation and age, sex, serum lipids, CRP, ESR, smoking habits and disease activity scores. Intima-media thickness of the common carotid artery was positively correlated with age and BASMI score (r = 0.55, P = 0.00; r = 0.22, P = 0.04, respectively).

CONCLUSION

This study demonstrates impairment of endothelial function in ankylosing spondylitis.

Changing associations between progressive cardiovascular autonomic neuropathy and carotid atherosclerosis with increasing duration of type 2 diabetes mellitus

To clarify associations between cardiovascular autonomic neuropathy (CAN) and the progression of carotid artery atherosclerosis in Type 2 diabetic patients, cardiovascular autonomic nerve function was related to carotid artery ultrasound in 61 Type 2 diabetic patients, 5 and 8 years after the diagnosis of diabetes. Between 5 and 8 years after diagnosis, age-adjusted acceleration index (AI) decreased (from -0.306+/-1.034 to -0.702+/-1.072; P=.0139), whereas age-adjusted expiration/inspiration (E/I) ratio was unchanged (-0.583+/-1.038 and -0.828+/-1.028; P=.1164). Intima-media thickness (IMT) increased in both the common carotid artery (CCA; from 0.854+/-0.219 to 0.913+/-0.241 mm; P<.0001) and the carotid bulb (from 1.789+/-0.714 to 2.128+/-0.881 mm; P<.0001), corresponding to a yearly IMT increase of 0.032+/-0.039 mm in the CCA and 0.146+/-0.204 mm in the carotid bulb. This value did not correlate with the AI or E/I ratios. In age-controlled partial correlation in the first examination, AI correlated inversely with mean (r=-.33, P=.018) IMT in the CCA, but not with IMT in the carotid bulb (r=-.14, P=.303). However, in contrast to the first examination, at follow-up, AI correlated inversely with the mean IMT of the carotid bulb (r=-.40, P=.007), lumen diameter of the CCA (r=-.31, P=.034), and plaque score (r=-.29, P=.041), but not with IMT of the CCA (r=-.04, P=.861). There were no correlations between the E/I ratio and carotid variables. In conclusion, CAN was associated with features of carotid atherosclerosis, which, in the carotid bulb, might affect baroreceptor function with the progression of Type 2 diabetes.

Noninvasive Detection of Coronary Artery Disease by Arterio-Oscillo-Graphy

Coronary artery disease (CAD) causes oscillations in peripheral arteries. Oscillations of the walls of the brachial arteries of 51 patients were recorded [together with the electrocardiogram (ECG)] by an accelerometer at different cuff pressures. By analyzing the energy of the oscillations in the 30-250 Hz band, 16 of 22 patients with CAD and 26 of 29 non-CAD subjects were classified correctly, independent of the ECG, and with no effect of heart murmurs.

Irbesartan and Lipoic Acid Improve Endothelial Function and Reduce Markers of Inflammation in the Metabolic Syndrome

Background— The metabolic syndrome is associated with increased angiotensin II activity, induction of a proinflammatory and oxidative state, and endothelial dysfunction. We evaluated the ability of irbesartan, an angiotensin receptor blocker, and lipoic acid, an antioxidant, to affect endothelial function and inflammation in patients with the metabolic syndrome.

Methods and Results— We randomized 58 subjects with the metabolic syndrome in a double-blinded manner to irbesartan 150 mg/d (n=14), lipoic acid 300 mg/d (n=15), both irbesartan and lipoic acid (n=15), or matching placebo (n=14) for 4 weeks. Endothelium-dependent and -independent flow-mediated vasodilation was determined under standard conditions. Plasma levels of interleukin-6, plasminogen activator-1, and 8-isoprostane were measured. After 4 weeks of therapy, endothelium-dependent flow-mediated vasodilation of the brachial artery was increased by 67%, 44%, and 75% in the irbesartan, lipoic acid, and irbesartan plus lipoic acid groups, respectively, compared with the placebo group. Treatment with irbesartan and/or lipoic acid was associated with statistically significant reductions in plasma levels of interleukin-6 and plasminogen activator-1. In addition, treatment with irbesartan or irbesartan plus lipoic acid decreased 8-isoprostane levels. No significant changes in blood pressure were noted in any of the study groups.

Conclusions— Administration of irbesartan and/or lipoic acid to patients with the metabolic syndrome improves endothelial function and reduces proinflammatory markers, factors that are implicated in the pathogenesis of atherosclerosis.

Non-invasive evaluation of endothelial function in hypertensive elderly patients

Impaired endothelium-dependent vasomotion is a diffuse disease process resulting in abnormal regulation of blood vessel tone and loss of several atheroprotective effects of the normal endothelium. The aim of the present study was to investigate the effects of aging and hypertension on endothelial function. Sixty-six geriatric subjects with ages over 60 (48 hypertensive and 18 healthy) and 40 middle-aged subjects (16 hypertensive and 24 healthy) were included in the study. Systemic vascular endothelial function was evaluated through measuring brachial arterial vasodilation, a physiologic answer to reactive hyperemia occured with increased blood flow in the vessel after transient ischemia (flow-mediated dilation, FMD%), and with carotid artery intima-media thickness (IMT) measurement, using high-resolution ultrasonography. Endothelial independent vasodilation was also measured after administration of sublingual isosorbide dinitrate (isosorbide dinitrate mediated dilation, IDNMD%). FMD% was significantly decreased in elderly and/or hypertensive (HT) patients (geriatric HT: 9.5 +/- 4.7%, geriatric non-HT: 12.7 +/- 5.5%, middle-aged HT: 12.9 +/- 4.3% and middle-aged non-HT: 18.9 +/- 8.1%) (geriatric HT versus geriatric non-HT (P = 0.02), geriatric HT versus middle-aged HT (P = 0.01), geriatric non-HT versus middle-aged non-HT (P = 0.008)). Both FMD% and IDNMD% were inversely correlated with age, baseline vessel diameter and carotid artery intima-media thickness. FMD% was also inversely correlated with diastolic blood pressure. No correlation was found between FMD% and systolic blood pressure, serum cholesterol and triglyceride levels. Endothelium dependent (EDD) and independent dilatation of large arteries decreased with aging even in the healthy elderly, and FMD further declined in HT elderly patients, indicating that age and hypertension independently impair endothelial function. Positive correlations with age and hypertension, and significant inverse correlation with FMD, makes carotid artery IMT a possible indicator of endothelial function.

Tamoxifen improves endothelial function and reduces carotid intima-media thickness in postmenopausal women

BACKGROUND

Tamoxifen is a selective estrogen-receptor modulator shown to improve several cardiovascular risk factors in postmenopausal women with breast cancer. In animal studies tamoxifen inhibits the progression of atherosclerosis. Although the presence of a history with tamoxifen treatment is related to a lower intima-media thickness (IMT) of the common carotid artery, data from controlled follow-up studies are lacking to support this observation.

METHODS

We examined 14 postmenopausal women with early stage breast cancer with indication for tamoxifen treatment (20 mg/d) and 13 healthy postmenopausal women. Flow-mediated dilatation (FMD) of the brachial artery, combined carotid IMT, and aortic pulse wave were measured before and 6 months after treatment in the tamoxifen group and at the same times in the control group.

RESULTS

FMD and IMT were significantly increased and decreased, respectively, in the treatment group compared to the control group (FMD: +2.2% +/- 0.9% vs +0.085% +/- 1%, P =.012; IMT: -0.088 +/- 0.03 mm vs +0.04 +/- 0.03 mm, P =.018, mean +/- standard error of the mean, treatment vs control group). These differences remained significant even when adjusted for age, duration of menopause, and cardiovascular risk factors. Low-density lipoprotein cholesterol was also significantly reduced after tamoxifen treatment.

CONCLUSIONS

Tamoxifen treatment slows the progression of atherosclerosis in postmenopausal women with breast cancer as assessed by changes in carotid IMT. An improvement in endothelial function and blood lipid profile may be the reason for this beneficial effect.