Atherosclerotic Plaques In Carotid Arteries Research Articles

Soluble low-density lipoprotein receptor-related protein 1 as a surrogate marker of carotid plaque inflammation assessed by 18F-FDG PET in patients with a recent ischemic stroke

Background18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) identifies carotid plaque inflammation and predicts stroke recurrence.AimOur aim was to evaluate the performance of soluble low-density lipoprotein receptor-related protein 1 (sLRP1) as an indicator of carotid plaque inflammation.MethodsA prospective study was conducted among adult patients with recent (< 7 days) anterior circulation ischemic stroke and at least one atherosclerotic plaque in the ipsilateral internal carotid artery. Patients underwent an early (< 15 days from inclusion) 18F-FDG PET, and the maximum standardized uptake value (SUVmax) within the plaque was measured. sLRP1 levels were measured in plasma samples by ELISA. The association of sLRP1 with SUVmax was assessed using bivariate and multivariable linear regression analyses. Hazard ratios (HR) were estimated with Cox regression to evaluate the association between circulating sLRP1 and stroke recurrence.ResultsThe study was conducted with 64 participants, of which 57.8% had ≥ 50% carotid stenosis. The multivariable linear and logistic regression analyses showed that sLRP1 was independently associated with (i) SUVmax within the plaque (β = 0.159, 95% CI 0.062–0.257, p = 0.002) and (ii) a probability of presenting SUVmax ≥ 2.85 g/mL (OR = 1.31, 95% CI 1.00–1.01, p = 0.046), respectively. Participants with stroke recurrence showed higher sLRP1 levels at baseline [6447 ng/mL (4897–11163) vs. 3713 ng/mL (2793–4730); p = 0.018].ConclusionssLRP1 was independently associated with carotid plaque inflammation as measured by 18F-FDG PET in patients with recent ischemic stroke and carotid atherosclerosis.

Metformin Directly Binds to MMP-9 to Improve Plaque Stability

Vulnerable atherosclerotic plaque rupture is the principal mechanism that accounts for myocardial infarction and stroke. High matrix metalloproteinase-9 (MMP-9) expression and activity have been proven to lead to plaque instability. Metformin, a first-line treatment for type 2 diabetes, is beneficial to plaque vulnerability. However, the mechanism underlying its anti-atherogenic effect remains unclear. Molecular docking and surface plasmon resonance experiments showed that metformin directly interacts with MMP-9, and incubated MMP-9 overexpressing HEK293A cells with metformin (1 μmol·L-1) significantly attenuates MMP-9's activity using zymography and MMP activity assays. Moreover, metformin treatment drives MMP-9 degradation. Next, we constructed a carotid artery atherosclerotic plaque model and administered consecutive 14-day metformin (200 mg·kg-1·d-1) treatment by intragastric gavage. Immunofluorescence staining of the right carotid common artery and serum MMP activity assay results showed that metformin treatment decreased local plaque MMP-9 protein level and circulating MMP-9 activity, respectively. Histochemical staining revealed that after metformin treatment, the collagen content in plaque was significantly preserved, and the plaque vulnerability index decreased. These findings suggested that metformin improved atherosclerotic plaque stability by directly binding to MMP-9 and driving its degradation.

Carotid atherosclerosis in people of European, South Asian and African Caribbean ethnicity in the Southall and Brent revisited study (SABRE).

Atherosclerotic cardiovascular disease (ASCVD) risk differs by ethnicity. In comparison with Europeans (EA) South Asian (SA) people in UK experience higher risk of coronary heart disease (CHD) and stroke, while African Caribbean people have a lower risk of CHD but a higher risk of stroke. To compare carotid atherosclerosis in EA, SA, and AC participants in the Southall and Brent Revisited (SABRE) study and establish if any differences were explained by ASCVD risk factors. Cardiovascular risk factors were measured, and carotid ultrasound was performed in 985 individuals (438 EA, 325 SA, 228 AC). Carotid artery plaques and intima-media thickness (cIMT) were measured. Associations of carotid atherosclerosis with ethnicity were investigated using generalised linear models (GLMs), with and without adjustment for non-modifiable (age, sex) and modifiable risk factors (education, diabetes, hypertension, total cholesterol, HDL-C, alcohol consumption, current smoking). Prevalence of any plaque was similar in EA and SA, but lower in AC (16, 16, and 6%, respectively; p < 0.001). In those with plaque, total plaque area, numbers of plaques, plaque class, or greyscale median did not differ by ethnicity; adjustment for risk factors had minimal effects. cIMT was higher in AC than the other ethnic groups after adjustment for age and sex, adjustment for risk factors attenuated this difference. Prevalence of carotid artery atherosclerotic plaques varies by ethnicity, independent of risk factors. Lower plaque prevalence in in AC is consistent with their lower risk of CHD but not their higher risk of stroke. Higher cIMT in AC may be explained by risk factors. The similarity of plaque burden in SA and EA despite established differences in ASCVD risk casts some doubt on the utility of carotid ultrasound as a means of assessing risk across these ethnic groups.

Phenotyping of embolic cryptogenic stroke based on ultrasound diagnosis and determination of serum concentration NT-proBNP

Determining the potential mechanisms underlying cryptogenic ischemic stroke is essential to guide diagnostic discovery and personalize secondary prevention.Purpose is to study the phenotypes of embolic stroke of undetermined source (ESUS) based on ultrasound diagnosis and determination of the serum concentration of pro-natriuretic N-terminal peptide B-type (N-Terminal Pro-brain Natriuretic Peptide, NT-proBNP).Materials and methods. 141 patients with ESUS were examined. In addition to the standard examination aimed at fi nding the cause of stroke, the functional characteristics of the left atrium were assessed using the emptying fraction (left atrial emptying fraction, LAEF) and the functional index (left atrial function index, LAFI), and the concentration of NT-proBNP in blood serum was also measured.Results. The most common potential sources of embolism were atherosclerotic plaques in the stroke-associated carotid artery with stenosis in 30–49% (31.9% of patients) and atrial cardiopathy with a decrease in LAEF &lt; 51.8% (24.8% of patients). An analysis of combinations of potential sources showed that 46.1% of patients had a negative phenotype, 21.3% of patients had a cardiac phenotype, 19.1% of patients had an atherosclerotic phenotype, and 13.5% of the examined patients had a mixed phenotype. Patients with a cardio-atherosclerotic phenotype diff ered from patients with a negative phenotype by higher disability on the Rankin scale at discharge from the hospital.Conclusion. The main potential embolic sources in patients with ESUS are non-stenosing carotid atherosclerosis and atrial cardiopathy with decreased LAEF. Cardiac and atherosclerotic phenotypes are determined in a quarter of patients, a mixed phenotype is found in every seventh patient, while in almost half of the patients no sources of embolism are found.

ROLE OF NON-CONTRAST MAGNETIC RESONANCE ANGIOGRAPHY IN THE DIAGNOSIS OF THE ATHEROSCLEROTIC LESIONS OF THE EXTRACRANIAL CAROTID ARTERIES

Formation of atherosclerotic plaque in the carotid arteries is the leading factor of hemodynamic disturbance in the cere-bral arteries. Visualization and characteristic of these plaques are most important factors from the viewpoint of preven-tive treatment- surgical or conservative. The goal of this study was to assess sensitivity and specificity of non-contrast MRA in evaluation and characteristics of atherosclerotic plaques in the extracranial carotid arteries. Our data was ob-tained from 130 patients: 38 were female (29.2%) and 92-male (70.8%). The middle age is 54.8 years (range 17-78 years). Patients were subjected to 3 diagnosis procedures, namely 85 patients were investigated by Doppler USG &amp; 45 patients by MRA method. All patients underwent selective cerebral arterial angiography by DSA as a gold standard method. From 130 patients 27 patients had no atherosclerotic disease; 57 had bilateral atherosclerotic changes; 46 pa-tients had monolateral carotid atherosclerotic process. From 260 investigated carotid arteries 51 arteries were detected with complete occlusion (22 right and 21 left occlusion), in 4 patients (8 carotid arteries) bilateral occlusion was seen. 54 carotid arteries had severe degree of stenosis. From this stenosis 27 arteries were more than 90%.32 carotid arteries had moderate degree of stenosis. In 23 carotid arteries mild degree was seen, but in a 100 carotid arteries had complete pa-tency. We concluded that complex noninvasive methods- colored Doppler USG and non-contrast MRA distinguished good accuracy (90%) and may be used as an alternative to DSA.

Assessment of the prevalence of target organ damage at various stages of the cardiometabolic continuum. According to the ESSE RF study

Objective: to assess the prevalence of target organ damage (TOD) at various stages of the cardiometabolic continuum, including abdominal obesity (AO) without metabolic syndrome (MS), MS, and type 2 diabetes mellitus (DM).Materials and methods: this study presents an analysis of data from a sample of residents of Tomsk (1,104 examined from an unorganized adult population of 25-64 years), performed within the framework of the ESSAY RF-2012 project (Epidemiology of Cardiovascular Diseases in the Regions of the Russian Federation). The analysis included the presence of LV hypertrophy (LVH), a decrease in glomerular filtration rate (GFR), an increase in the thickness of the intima-media complex (TIM), the presence of atherosclerotic plaques (ASP) in the common carotid arteries (CCA).Results: TODs were already reported among individuals with isolated AO (without MS), whose prevalence was statistically significantly higher compared to those with normal body weight. Atherosclerosis of CCA turned out to be the most frequent TOD phenotype, ASP was detected in 22% of individuals with isolated AO, in 33% patients with MS and 35% patients with type 2 DM, the second most common was LVH, which was detected in 0.8%, 4,7% and 17,5% of cases, respectively, the least common was a decrease in GFR – in 1,37%, 3,7% and 6,7% of patients, respectively. Differences in the frequency of TOD in all groups were statistically significant (p &lt; 0,01).Conclusions: Thus, the prevalence of TODs detected already at the stage of isolated AO progressively increased from group to group, as they moved along the cardiometabolic continuum.

A Method to Study the Correlation Between Local Collagen Structure and Mechanical Properties of Atherosclerotic Plaque Fibrous Tissue.

The rupture of atherosclerotic plaques in coronary and carotid arteries is the primary cause of fatal cardiovascular events. However, the rupture mechanics of the heterogeneous, highly collagenous plaque tissue, and how this is related to the tissue's fibrous structure, are not known yet. Existing pipelines to study plaque mechanics are limited to obtaining only gross mechanical characteristics of the plaque tissue, based on the assumption of structural homogeneity of the tissue. However, fibrous plaque tissue is structurally heterogeneous, arguably mainly due to local variation in the collagen fiber architecture. The mechano-imaging pipeline described here has been developed to study the heterogeneous structural and mechanical plaque properties. In this pipeline, the tissue's local collagen architecture is characterized using multiphoton microscopy (MPM) with second-harmonic generation (SHG), and the tissue's failure behavior is characterized under uniaxial tensile testing conditions using digital image correlation (DIC) analysis. This experimental pipeline enables correlation of the local predominant angle and dispersion of collagen fiber orientation, the rupture behavior, and the strain fingerprints of the fibrous plaque tissue. The obtained knowledge is key to better understand, predict, and prevent atherosclerotic plaque rupture events.

Features of Atherosclerosis of the Carotid Arteries in Elderly patients with Acute Coronary Syndrome

Aim. To study features of atherosclerosis and signs of instability of atherosclerotic plaque in the carotid arteries by ultrasound duplex scanning of elderly patients with myocardial infarction or unstable angina.Material and methods. The study included 87 patients with ACS and 78 patients without ACS aged 75 and over. Ultrasound duplex scanning of carotid arteries was carried out with Philips EPIQ5 ultrasound system and L12–3 linear array transducer on the 2–5 day from the moment of hospitalization. Quantitative and structural indicators of atherosclerosis of the carotid arteries were assessed .Results. The frequency of detection of atherosclerotic plaques in carotid arteries in elderly patients with ACS was signifi cantly higher than in patients without ACS – 78 and 67 % (p=0,179). Patients with ACS compared with the group without ACS more often had signs of instability of atherosclerotic plaque: heterogenous structure – 28,8 and 19,3 % (p=0,017), hypoechogenic component – 39,2 and 9,9 % (p&lt;0,001), irregular surface – 46,3 and 8,2 % (р&lt;0,001), local calcifi cation –14,2 and 7 % (р=0,001). At the same time, ulcerated atherosclerotic plaques were found only in the group of patients with ACS – 1,9 % (р=0,412). The incidence of atherosclerotic plaques in carotid arteries among men was higher in the group with ACS compared to patients without ACS – 36,2 and 23,4 % (р=0,003); among women the data are higher in the group without ACS compared with the group of patients with ACS – 76,6 and 63,8 % (р=0,003).Conclusion. Atherosclerotic plaques in carotid arteries among elderly patients are more common in the group of patients with ACS. As the same time, among this group atherosclerotic plaques with signs of instability were significantly more common found.

Н-тип артеріальної гіпертензії: зв’язок з атеросклерозом сонних артерій

Мета роботи – визначити зв’язок артеріальної гіпертензії (АГ) та гіпергомоцистеїнемії (ГГЦ) з наявністю атеросклеротичних бляшок у сонних артеріях.Матеріали і методи. Робота виконана в рамках дослідження ХІПСТЕР в Україні. У дослідження залучено 40 пацієнтів з АГ I і II ступеня (середній рівень офісного систолічного (САТ) / діастолічного (ДАТ) артеріального тиску – (155,88/92,60±1,63/1,43) мм рт. ст.). Вік хворих становив 26–74 роки, у середньому (55,85±2,09) року. Пацієнтів з рівнем гомоцистеїну ≥ 10 мкмоль/л визначали як пацієнтів з ГГЦ (Н-тип АГ). Жорсткість судин встановлювали за швидкістю поширення пульсової хвилі (ШППХ). Пацієнтів обстежували на початку та через 6 місяців лікування. Наявність атеросклерозу сонних артерій визначали на початку та через 12 місяців спостереження. Результати та обговорення. Виявлено, що oфісний САТ у пацієнтів з АГ Н-типу на початку і через 6 місяців лікування був вищим порівняно з пацієнтами без ГГЦ ((156,45±1,04) проти (152,55±1,41) мм рт. ст. на початку (р&lt;0,05) і (130,65±0,96) проти (126,97±1,08) мм рт. ст. через 6 місяців (р&lt;0,05)). Пацієнти з АГ Н-типу порівняно з пацієнтами без ГГЦ мали більш виражений ступінь інсулінорезистентності (індекс НОМА (4,27±0,18) проти (3,20±0,24) ум. од., р&lt;0,05). У 56,7 % (n=17) пацієнтів з АГ Н-типу та у 40,0 % (n=4) пацієнтів з АГ без ГГЦ було виявлено атеросклеротичні бляшки в сонних артеріях (p&lt;0,05). Пацієнти з АГ Н-типу мали вищу поширеність атеросклерозу сонних артерій – площа атеросклеротичної бляшки, виміряна за NASCET, становила 43,4 проти 26,7 % (p&lt;0,05) та була більшою, ніж у пацієнтів із АГ без ГГЦ. Через 12 місяців нові атеросклеротичні бляшки було виявлено у 3 (10,0 %) пацієнтів із АГ Н-типу, а в групі осіб з АГ без ГГЦ не виявлено в жодного пацієнта. При проведенні регресійного аналізу рівень гомоцистеїну в сироватці крові асоціювався з ШППХ незалежно від зниження АТ на тлі терапії, а також із рівнем холестерину ліпопротеїнів низької щільності (ХСЛПНЩ) та наявністю атеросклеротичних бляшок у сонних артеріях. Рівень гомоцистеїну був пов’язаний із ШППХе після лікування (β=0,307; р=0,001), ХСЛПНЩ до лікування (β=–1,501; р=0,017), наявністю атеросклеротичних бляшок після лікування (β=5,236; р=0,031).Висновки. Н-тип артеріальної гіпертензії асоціювався з наявністю атеросклеротичного стенотичного ураження сонних артерій.

Uric Acid is Independently Associated with Atherosclerosis among Healthy Chinese in Taiwan

&lt;p&gt;Objective: This study investigated the association between uric acid and atherosclerosis in a community population. Methods: We enrolled 2,790 subjects aged &amp;ge; 30 years from the CardioVascular Disease FACTor Two-Township Study. The common carotid artery intima-media thickness (IMT) and atherosclerotic plaque were used as indices of atherosclerosis. Pearson&amp;rsquo;s correlation coefficient, the general linear model, and a logistic model were used to assess the association between uric acid and atherosclerosis. Results: Elevated uric acid was moderately associated with obesity, dyslipidemia, elevated blood pressure, impaired glucose, insulin resistance (all correlation coefficients &lt; 0.05) and IMT (r: 0.12, p &lt; 0.05). Subjects were classified into four groups according to uric acid levels: group 1 (&lt;5.0 mg/dl), group 2 (5.0&amp;ndash;6.9 mg/dl), group 3 (7.0&amp;ndash;8.9 mg/dl) and group 4 (&amp;ge;9.0 mg/dl). The age and sex-adjusted mean of IMT was 0.54 in group 1, was 0.55 in both groups 2 and 3, and the mean of IMT (0.59 mm) in group 4 (&amp;ge;9.0 mg/dl) was significantly higher. Uric acid (&amp;ge;9.0 mg/dl) was significantly and positively associated with higher IMT (multivariate adjusted mean: 0.58 mm), independent of other risk factors, and atherosclerosis (&amp;ge;75th IMT value in the population) with an odds ratio of 2.67 (95% confidence intervals = 1.55&amp;ndash;4.59). This association remained significant in a healthy subgroup (without metabolic syndrome, hypertension, or diabetes; OR = 2.91; CI = 1.16&amp;ndash;7.25). Conclusion: Uric acid of 9 mg/dL and/or above was independently associated with atherosclerosis in terms of IMT measures in the general population and those without metabolic syndrome. Further study is warranted.&lt;/p&gt; &lt;p&gt;&amp;nbsp;&lt;/p&gt;

Teaching Video NeuroImage: Amaurosis Fugax Due to Recurrent Central Retinal Artery Occlusion by Microemboli.

A previously healthy 71-year-old woman with hypercholesterolemia and current tobacco use presented with transient painless vision loss in the left eye without other neurologic abnormalities. The 30-second episodes, followed by a recovery, repeated in 2- to 3-minute intervals.1 Microemboli passing through central retinal artery (CRA) vasculature (Video 1) originated from a complicated atherosclerotic plaque in the left internal carotid artery (Figure). After receiving intravenous thrombolysis 5 hours after symptom onset,2 she reported a scotoma in the inferior part of her left eye, which persisted 2 years later. Retinal embolism from carotid artery disease is the most common cause of CRA occlusion.

Comparison of carotid atherosclerotic plaque characteristics between symptomatic patients with transient ischemic attack and stroke using high-resolution magnetic resonance imaging

BackgroundThis study aimed to compare the characteristics of carotid plaques between patients with transient ischemic attack (TIA) and ischemic stroke using magnetic resonance (MR) imaging.MethodsPatients with a recent ischemic stroke or TIA who exhibited atherosclerotic plaques of carotid arteries in the symptomatic sides determined by MR vessel wall imaging were recruited. The plaque morphology and compositions including intraplaque hemorrhage (IPH), lipid-rich necrotic-core (LRNC) and calcification were compared between TIA and stroke patients. Logistic regression was performed to relate the plaque characteristics to the types of ischemic events.ResultsA total of 270 patients with TIA or ischemic stroke were recruited. Stroke patients had a significantly higher prevalence of diabetes (42.2% vs. 28.2%, p = 0.021), greater mean wall area (35.1 ± 10.1 mm2 vs. 32.0 ± 7.7 mm2, p = 0.004), mean wall thickness (1.3 ± 0.2 mm vs. 1.2 ± 0.2 mm, p = 0.001), maximum normalized wall index (NWI)(63.9% ± 6.0% vs. 62.2% ± 5.9%, p = 0.023) and %volume of LRNC (9.7% ± 8.2% vs. 7.4% ± 7.9%, p = 0.025) in the carotid arteries compared to those with TIA. After adjustment for clinical factors, above characteristics of carotid arteries were significantly associated with the type of ischemic events. After further adjustment for maximum NWI, this association remained statistically significant (OR, 1.41; CI, 1.01–1.96; p = 0.041).ConclusionsIschemic stroke patients had larger plaque burden and greater proportion of LRNC in carotid plaques compared to those with TIA. This study suggests that ischemic stroke patients had more vulnerable plaques compared to those with TIA.

Echolucent Carotid Plaques Becomes More Echogenic over Time – A 3D Ultrasound Study

Despite the presence of only a few established risk factors, some patients will experience atherosclerotic events. Therefore, methods for improved risk stratification for atherosclerotic events are wanted. We aimed to detect changes in carotid artery atherosclerotic plaque volume and echogenicity over time in patients with an acute thromboembolic event and in patients with chronic atherosclerotic disease, both treated with statin, using a novel 3D ultrasound system. We included two cohorts of patients; 70 patients, naïve to statin treatment, admitted with acute, first-time myocardial infarction (aMI), and 69 patients who had been on statin treatment for a minimum of 6 months with chronic peripheral arterial disease (cPAD). 3D ultrasound examination was performed at baseline and after 3 and 12 months. Plaque volume was quantified in 3D ultrasound plaque acquisitions, and echogenicity was assessed using grayscale median (GSM) and normalized with adventitia as reference. The aMI group had darker plaques than the cPAD group at baseline (mean GSM: 60.98, standard deviation (SD): 24.09 vs. 71.75, SD: 21.55; P=0.006), 3 months (63.64, SD: 20.47 vs. 73.44, SD: 20.46; P=0.006) and at 12 months follow-up (59.25, SD: 18.07 vs. 71.02, SD: 22.31; P=0.004). The differences were not significant after adjusting for traditional risk factors. Dividing both groups by the median GSM, the darkest half of the aMI group's had an increase in GSM mainly within the first 3 months (10.49, CI 95%: 2.45 to 18.53; P=0.012) and hereafter remained unchanged at 12 months follow-up (-0.53, CI 95%: -7.28 to 6.22, P=0.875). In the darkest cPAD group GSM also increased within 3 months (8.14, CI 95%: 1.85-14.32, P=0.012) and hereafter stabilized till 12 months (-2.54, CI 95%: -9.62 to 4.53, P=0.475). Plaque volume did not change in the aMI group from baseline (median: 55.41mm3, interquartile range (IQR): 24.24-84.31) to 12 months (58.67mm3, IQR: 31.81-93.51) (P=0.220) whereas there was a small decrease in the cPAD group from baseline (71.63mm3, IQR: 40.12-135.61) to 12 months (67.73mm3, IQR: 31.00-122.38) (P=0.026). Echolucent carotid plaque, assessed with the novel 3D matrix ultrasound system, had increasing GSM within 3 months period, indicating stabilization of the more vulnerable plaques in aMI and cPAD patients. Plaque volume decreased over 12 months follow-up in a long-term statin-treated patient with cPAD, but not during the first 12months statin therapy in patients with aMI.

Plasma sICAM-1 as a Biomarker of Carotid Plaque Inflammation in Patients with a Recent Ischemic Stroke

18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) identifies carotid plaque inflammation and predicts stroke recurrence in patients with atherothrombotic stroke. The aim of the study was to identify plasma inflammatory biomarkers associated with plaque inflammation according to 18F-FDG uptake. We conducted a prospective study of consecutive adult patients with a recent (< 7 days) anterior circulation ischemic stroke and at least one atherosclerotic plaque in the ipsilateral internal carotid artery. We included 64 patients, 57.8% of whom showed a carotid stenosis ≥ 50%. All patients underwent an early (< 15 days from inclusion) 18F-FDG PET, and a blood sample was obtained at days 7 ± 1 from the stroke. The plasma concentration of 16 inflammation-related molecules was analyzed in a Luminex using xMAP technology. Multivariable linear regression was used to assess the association between plasma biomarkers and the standardized uptake value (SUV) of 18F-FDG uptake. Soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular adhesion molecule-1 (sVCAM-1), and fractalkine (FKN) were independently associated with plaque inflammation (β = 0.121, 95% CI 0.061–0.181, p < 0.001; β = 0.144, 95% CI 0.012–0.276, p = 0.033; β = 0.136, 95% CI 0.037–0.235, p = 0.008). In a multivariable logistic regression analysis, sICAM-1 was associated with SUVmax ≥ 2.85 (OR = 1.02, 95% CI 1.00–1.03, p = 0.020). Multivariable Cox regression was used to assess the association between biomarkers and stroke recurrence. sICAM-1 was associated with stroke recurrence (HR = 1.03, 95% CI 1.00–1.05, p = 0.002). In summary, elevated concentrations of sICAM-1 were associated with carotid plaque inflammation and an increased risk of stroke recurrence in patients with recent ischemic stroke and carotid atherosclerosis.

CD93 in macrophages: A novel target for atherosclerotic plaque imaging?

Noninvasive imaging atherosclerotic (AS) plaque is of great importance for early diagnosis. Recently, CD93 in MΦ was linked to atherosclerosis development. Herein, we have investigated whether CD93 in MΦ is a potential novel target for atherosclerotic plaque imaging. CD93hi and CD93lo MΦ were prepared with or without LPS stimulation, before biological activity was evaluated. A rat AS model was produced with left carotid artery clamped. Whole‐body/ex vivo phosphor autoradiography of the artery and biodistribution were investigated after incorporation of 3H‐2‐DG into CD93hi and CD93lo MΦ or after 125I‐α‐CD93 (125I‐anti‐CD93mAb) injection. The plaque tissue was subjected to CD93/CD68 immunofluorescence/immunohistochemistry staining. CD93hi and CD93lo MΦ cells were successfully prepared without significant effect on bioactivity after incorporative labelled with 3H‐2‐DG. The AS model was successfully established. Biodistribution studies showed that adoptive transfer of 3H‐2‐DG‐CD93hi MΦ or 125I‐ α‐CD93 injection resulted in accumulation of radioactivity within the atherosclerotic plaque in the clamped left carotid artery. T/NT (target/non‐target, left/right carotid artery) ratio was higher in the 3H‐2‐DG‐CD93hi MΦ adoptive transfer group than in the 3H‐2‐DG‐CD93lo MΦ group (p < .05). Plaque radioactivity in the 125I‐α‐CD93 injection group was significantly higher than in the 125I‐IgG control group (p < .01). The higher radioactivity accumulated in the clamped left carotid artery was confirmed by phosphor autoradiography. More importantly, CD93/CD68 double‐positive MΦ accumulated at the atherosclerotic plaque in 3H‐2‐DG‐CD93hi MΦ adoptive transfer group, which correlated with plaque radioactivity (r = .99, p < .01). In summary, both adoptive‐transferred 3H‐2‐DG‐labelled CD93hi MΦ and 125I‐α‐CD93 injection specifically targeted CD93 in atherosclerotic plaque. CD93 is a potential target in atherosclerotic plaque imaging.

Imaging Approaches to the Diagnosis of Vascular Diseases.

Vascular imaging is a complex field including numerous modalities and imaging markers. This review is focused on important and recent findings in atherosclerotic carotid artery plaque imaging with an emphasis on developments in magnetic resonance imaging (MRI) and computed tomography (CT). Recent evidence shows that carotid plaque characteristics and not onlyestablished measures of carotid plaque burden and stenosis are associatedindependently with cardiovascular outcomes. On carotid MRI, the presence of a lipid-rich necrotic core (LRNC) has been associated with incident cardiovascular disease (CVD) events independent of wall thickness, a traditional measure of plaque burden. On carotid MRI, intraplaque hemorrhage (IPH) presence has been identified as an independent predictor of stroke. The presence of a fissured carotid fibrous cap has been associated with contrast enhancement on CT angiography imaging. Carotid artery plaque characteristics have been associated with incident CVD events, and advanced plaque imaging techniques may gain additional prominence in the clinical treatment decision process.

Blood microflora of patients with atherosclerotic vascular lesions and microflora of atherosclerotic plaques of carotid arteries

Aim of the study was to assess the frequency of microflora detection in the blood of patients with atherosclerotic vascular lesions and middle-aged patients without clinical symptoms of atherosclerosis. Compare the nature of microflora isolated from blood and the range of microorganisms isolated from atherosclerotic plaques (AP) of patients with carotid arteries atherosclerosis. Material and methods. The hemocultures of 118 men and 33 women with atherosclerosis (mean age 55.6 years) as well as 10 blood samples of 3 men and 7 women formed into a control group (mean age 37 years) were examined. Test samples were cultivated for 6 months. Tissue platings of carotid arteries AP in 11 women and 24 men of the main group (mean age 58.0) were incubated for 2 months. Methods based on Student’s t-test and Mann-Whitney U-test were used for statistical analysis of the obtained results. Results. Propionibacterium acnes hemocultures were detected in 9.9 % of patients from the main and control groups. In blood Staphylococcus epidermidis and Stenotrophomonas maltophylia were detected in 0.7 % of samples. P. acnes and Staphylococcus spp. cultures were obtained from AP in 34.3 and 45.7 %, including both microorganisms in 8.6 % of samples. Conclusions. P. acnes cultures are found equally frequently in the blood of atherosclerotic patients and patients not yet diagnosed with atherosclerosis. This study confirmed the presence of the same-name microorganisms in blood and atherosclerotic plaques. In 5.7 % (2 of 35) it was possible to extract simultaneously a P. acnes culture from two loci (atherosclerotic tissue and blood) in specific individuals. Further detailed research is required to study the etiological significance of the microbial factor in the atherosclerotic plaque formation.

Adiponectin in normal and atherosclerotic intima of human aorta

Adiponectin (AN) is a protein synthesized by adipocytes that has regulatory effects on lipid and lipoprotein metabolism, increases tissue sensitivity to insulin, and modulates endothelial functions and inflammatory response. However, its involvement in the processes of atherogenesis remains poorly understood. To determine the localization and sources of AN in atherosclerotic and normal human aortic intima. Immunohistochemical study was performed on sections of atherosclerotic and normal human aorta obtained during autopsy. Reverse transcription real-time PCR was performed using biopsies of para-aortic and abdominal adipose tissue, intima-media of the thoracic aorta, atherosclerotic plaques of the human carotid and femoral arteries, as well as on endothelial cells isolated from the human thoracic aorta. Transendothelial transport of AN was evaluated in a two-chamber model using a monolayer of human endothelial cell hybridoma EA.Hy926. It has been established that AN is present in atherosclerotic but not in normal human aortic intima. At the same time, AN ADIPOQ mRNA was not detected either in the intima media of the human aorta, nor in isolated endothelial cells of the aorta, nor in cells of atherosclerotic plaques of the carotid and femoral arteries. AN slowly penetrated the endothelial monolayer in vitro, but this transport was significantly enhanced by the action of tumor necrosis factor-alpha (TNFa). Obtained data indicate that AN is present in atherosclerotic but not in normal aortic intima. We assume that AN is not synthesized by the cells of normal and atherosclerotic arterial walls, but permeates from the plasma. Transendothelial transport of AN, like many other plasma proteins, is activated during the development of atherosclerotic lesions, apparently under the action of pro-inflammatory cytokines, in particular, TNFα.

Diagnostic Value of Magnetic Resonance Imaging in Evaluating Carotid Artery Atherosclerotic Plaque Morphology

Magnetic Resonance Imaging has the ability to describe vessel wall thickness, plaque structure, distinguish fibrotic, fatty, calcific or hemorrhagic plaque contents with excellent soft tissue contrast. Our aim in this study is to determine symptomatic and asymptomatic carotid plaque morphology and imaging properties. We tried to understand whether plaque components in images match with histopathological sections. MRI was performed in 37 patients known to have carotid stenosis and endarterectomy decision has been taken. 24 patients were symptomatic and 13 were asymptomatic for carotid disease. A surface coil used in MRI; 5 cm of carotid segment was imaged with the carotid bifurcation in the middle. Necrotic core, fibrous cap, hemorrhage, calcification and intraluminal thrombus were determined in MR images. After surgery, the specimens were evaluated by a pathologist who was blind to the radiological findings. All plaque contents (necrotic core, hemorrhage, calcification and fibrous cap) can be imaged and separated from each-other with MRI. Necrotic core was detected in 87.9% of patients on MR images. No significant difference was found between symptomatic and asymptomatic cases in terms of the rate and dimensions of necrotic core on MRI. The presence of calcification did not show a significant difference between symptomatic and asymptomatic cases. The sensitivity of MRI in detecting in-plaque hemorrhage was calculated as 82.3% and specificity as 68.75%. The calculated rates were interpreted as MRI is significant in distinguishing cases without bleeding. Fibrous cap was more preserved in asymptomatic patients. The structure of the atheroma plaque can be imaged and distinguished from each other with MRI. The statistical results did not show the expected performance mainly due to the small number of asymptomatic cases, which was the main limitation of the study.

Influence of the internal carotid arteries stenosis on the hemodynamics of the circle of Willis communicating arteries: a numerical study

Modern authors argue that carotid arteries stenosis leads to changes in circle of Willis blood flow, which may contribute to aneurysm formation. It was found that up to 3.2 % of patients with carotid arteries stenosis have associated cerebral aneurysms. Moreover, it is known that performing a surgical intervention to remove carotid stenoses can lead to a decrease in cerebral aneurysm size or their complete disappearance. In this regard, the problem arises of studying effect of the carotid arteries stenosis on human brain vessels aneurysms development. In this work, a biomechanical study of the anterior communicating and posterior communicating arteries hemodynamics for various variants of the circle of Willis structure in combination with atherosclerotic plaques of carotid arteries was carried out. Based on computed angiography data, 45 models of the circle of Willis and carotid arteries with various degrees of stenosis and localization of atherosclerotic plaques were constructed and analyzed. Numerical modeling of the unsteady blood flow in the circle of Willis and carotid arteries was performed in Ansys CFX. Wall shear stress of the anterior and posterior communicating arteries were analyzed, as well as mass blood flows along these arteries. The influence of the carotid arteries stenosis degree, as well as their combination with anomalies in the circle of Willis on change in wall shear stresses and mass blood flows in communicating arteries, was evaluated. The most dangerous combinations of the carotid arteries stenosis and types of the cerebral arterial circle which increase the risk of developing communicating arteries aneurysms were identified.