Bilateral symmetry of human carotid artery atherosclerosis

Multi-perspective ultrasound evaluation of Carotid Intima-Media thickness in hemodialysis access patients and its possible use to predict clinical outcomes

BACKGROUND

Hemodialysis (HD) patients present an increased carotid intima-media thickness (CIMT) and calcified plaques, and studies have demonstrated that CIMT is predictor for cardiovascular death in this patient population; hence, the importance of identifying early non-invasive markers of atherosclerosis. We aim to propose a new three-perspective CIMT measuring method in HD population, and to further investigate the possible use and value of this method to predict outcomes.

METHODS

A cross-sectional study was conducted, the CIMT was measured with duplex ultrasound during the perioperative access planning. Software provided maximum CIMT in a 10 mm (mm) width of the common carotid artery. CIMT was measured in Right (R) and Left (L) carotid arteries, both in anterior (a), lateral (l), and posterior (p) view. The sum of these values (Ra+Rl+Rp+La+Ll+Lp) was completed and termed as Sixth Carotid Intimal (SCI) score. We stratified either in low (summation <4) or high (>=4) SCI score groups. Demographics, patency rates, complications, and mortality were collected; chi-square test was used for our analysis.

RESULTS

A total of 30 patients (mean age 49 years and 56% females) that underwent access creation in the upper arm from 2010 to 2016 were selected and studied. A low SCI score was found 19 patients and 11 had high SCI, no significant difference was observed in demographics, history cardiovascular disease, and clinical outcomes as early thrombosis, and primary, primary-assisted patency at 12 months. Interestingly, during the follow up period of 36 months a significant higher difference in late thrombosis rates occurred (63.6% vs 26.3%, p = .044) and a higher all-cause mortality (54.4% vs 15.7%, p = .025) in patients with SCI score group above 4.

CONCLUSIONS

The SCI score method, might offer a screening tool for traditional cardiovascular risk factors in HD patients. In this study, we demonstrate an increased rate in late thrombosis and mortality in those with high SCI. Further research is necessary to better define the role of CIMT in vascular surgical procedures.

Association of HIV and HCV Infection With Carotid Artery Plaque Echomorphology in the MACS/WIHS Combined Cohort Study

BACKGROUND

HIV and hepatitis C virus (HCV) are associated with increased risk of carotid artery atherosclerotic plaque and stroke. We examined associations of HIV- and HCV-related factors with echomorphologic features of carotid artery plaque.

METHODS

This cross-sectional study included participants from the MACS (Multicenter AIDS Cohort Study)/WIHS (Women's Interagency HIV Study) Combined Cohort Study who underwent high-resolution B-mode carotid artery ultrasound. Plaques were characterized from 6 areas of the right carotid artery. Poisson regression controlling for demographic and cardiometabolic risk factors determined adjusted prevalence ratios (aPRs) and 95% CIs for associations of HIV- and HCV-related factors with echomorphologic features.

RESULTS

Of 2655 participants (65% women, median age 44 [interquartile range, 37-50] years), 1845 (70%) were living with HIV, 600 (23%) were living with HCV, and 425 (16%) had carotid plaque. There were 191 plaques identified in 129 (11%) women with HIV, 51 plaques in 32 (7%) women without HIV, 248 plaques in 171 (28%) men with HIV, and 139 plaques in 93 (29%) men without HIV. Adjusted analyses showed that people with HIV and current CD4+ count <200 cells/µL had a significantly higher prevalence of predominantly echolucent plaque (aPR, 1.86 [95% CI, 1.08-3.21]) than those without HIV. HCV infection alone (aPR, 1.86 [95% CI, 1.08-3.19]) and HIV-HCV coinfection (aPR, 1.75 [95% CI, 1.10-2.78]) were each associated with higher prevalence of predominantly echogenic plaque. HIV-HCV coinfection was also associated with higher prevalence of smooth surface plaque (aPR, 2.75 [95% CI, 1.03-7.32]) compared with people without HIV and HCV.

CONCLUSIONS

HIV with poor immunologic control, as well as HCV infection, either alone or in the presence of HIV, were associated with different echomorphologic phenotypes of carotid artery plaque.

Evaluation of the Prevalence of Atherosclerosis Within the Course of Internal Carotid Artery in Cone Beam Computed Tomography Images

The aim of the present study was to retrospectively evaluate the gender-related and age-related prevalence and severity of calcifications within the segments of the internal carotid artery in cone beam computed tomography (CBCT). By using a documented visual scale, out of 400 CBCT examinations a total of 304 CBCT scans of adult patients over 40 years old were evaluated as to the prevalence and severity of intracranial calcifications within the segments of the internal carotid artery. Calcifications were found in 117 CBCT scans. These calcifications were detected along the extracranial (C1: 53%), petrous (C2: 22.2%), Lacerum (C3:27%), cavernous (C4: 94%), and ophthalmic-clinoid (C5/C6: 65%) segments. The Friedman test showed significant differences in the severity of calcifications among the internal carotid artery segments. The McNemar test showed no significant differences between calcifications on the right or left side segments. The Chi square test showed no significant differences in the prevalence of calcifications between men and women; it also showed that the prevalence of calcifications increased with increase in age (P < 0.05). In this study, the frequency and severity of calcifications decreased throughout the C4, C5/C6, and C1 segments in a descending order; moreover, an increased incidence of calcifications by increase in age was documented irrespective of gender.

Evaluation of the Incidental Prevalence of Soft Tissue Calcifications in the Neck Region with Cone Beam Computed Tomography

Objective: The aim of this study was to retrospectively evaluate the incidental prevalence of heterotopic soft tissue calcifications in the neck region, on Cone Beam Computed Tomography (CBCT) images, and their relationship with age and sex. Methods: A total of 6620 CBCT images were examined. CBCT images of 503 patients aged between 20 and 86 years were included in the study. Patients were grouped into five age groups: 20-30 (N = 132), 31-40 (N = 68), 41-50 (N = 92), 51-60 (N = 104), and 61 and above (N = 107). The images were assessed according to the presence of lymph node calcification, carotid artery calcification, thyroid cartilage, and triticeous cartilage calcification in the neck region. Descriptive statistics, crosstabs, and chi-square tests were used for data analysis. The significance level was set to 0.05 Results: At least one calcification was detected in 372 (73.9%) patients. The difference between the prevalence of each calcification according to age groups was statistically significant. A significant relationship was found between the presence of carotid artery calcification and the sex variable (p< .05). The presence of other calcifications did not show statistically significant differences associated with sex (p> .05). Conclusion: The results of this study showed a significant amount of soft tissue calcification in the neck region. The most common calcifications were thyroid cartilage calcifications, and the least common calcification was lymph node calcification.

Comparison between Traditional Chinese Medicine Constitution and Blood Biochemical Markers Associated with Left and Right Mammary Hyperplasia in Rural Areas of Southwest China

Background

Hyperplasia of mammary glands (HMG) is the breast disease with the highest clinical incidence. Many traditional Chinese medicine (TCM) doctors suggest that the treatment of HMG should be based on the left and right breast pain difference. However, these views are based on case reports, and an objective basis has not been established for treatment according to left-side and right-side differences.

Methods

We enrolled 150 patients who met the clinical diagnostic criteria of HMG. The incidence bias was determined according to the score difference between bilateral breast pain and mass in patients with HMG. A left group, right group, and bilateral group were included, and TCM constitution was investigated in each group. Blood biochemical indicators were measured for 120 fasting patients. We conducted a network pharmacology study of the key herb qingpi and chenpi, which are used by TCM doctors to treat different lateral HMG.

Results

In patients with biased onset of HMG, the results showed that the frequency and constitution score of stagnant blood in the L group were higher than those of the R group, and the frequency and constitution score of phlegm-dampness in the R group were higher than those of the L group. Both the L and R groups had high proportion of stagnant Qi. The results indicated that the concentration of coagulation factor VIII (FVIII) was higher in the L group than that in the R group, and the concentration of lipoprotein a (Lp-α) was higher in the R group than that in the L group. The results showed that sinensetin and neohesperidin contained in qingpi might interfere with platelet activation, thrombogenesis, prolactin signaling pathway, and atherosclerosis process, in removing “blood stasis” and eventually treating the left-leaning group of HMG patients. Sitosterol and citromitin contained in chenpi could regulate lipid metabolism by interfering with regulation of lipolysis in adipocytes, salivary secretion, estrogen signaling pathway, and thyroid hormone signaling pathway. Chenpi could eliminate “phlegm turbidity” and treat HMG patients in the right-leaning group.

Conclusions

We preliminarily confirmed that the clinical pathogenesis of HMG is not a left-right equilibrium and TCM constitution, coagulation function, and lipid metabolism may be used as the objective basis for the difference between the left and right in HMG pathogenesis. For left-sided HMG patients, the doctor can consider qingpi, herb of activating blood and removing stasis, to treat HMG. However, for right-sided HMG, we think doctors should apply herb of activating Qi and eliminating phlegm, such as chenpi.

Imaging Approaches to the Diagnosis of Vascular Diseases

PURPOSE OF REVIEW

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 FINDINGS

Recent evidence shows that carotid plaque characteristics and not only established measures of carotid plaque burden and stenosis are associated independently 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.

Prevalence and characteristics of atherosclerotic plaque: Left compared with right arteries and anterior compared with posterior circulation stroke

PURPOSE

To evaluate atherosclerotic plaque prevalence and characteristics between left and right cervicocephalic arteries and between anterior and posterior circulation stroke (ACS and PCS).

METHODS

This retrospective study included 284 patients with acute ischemic stroke (199 ACS and 85 PCS) involving large-artery atherosclerosis or small-artery occlusion. We assessed atherosclerotic plaque prevalence and characteristics (plaque type, plaque surface morphology, plaque distribution, location of calcified nodules and plaque thickness) in each segment and their comparisons between left and right arteries and between ACS and PCS.

RESULTS

The left subclavian artery (L-SA), common carotid artery (L-CCA) and intracranial vertebral artery (L-IVA) had significantly higher prevalence of atherosclerotic plaque than the right (R) corresponding arteries (70.1% versus 59.5%, P = 0.008), (48.1% versus 28.9%, P < 0.001), (23.9% versus 16%, P = 0.018), respectively. L-SA had a higher prevalence of mixed plaque (non-calcified > calcified) (19.6% versus 16.4%) and noncalcified plaque (51.9% versus 31.7%), and a lower prevalence of calcified plaque (8.9% versus 23.3%) and mixed plaque (calcified > non-calcified) (19.6% versus 28.6%) than R-SA, P < 0.001. The distribution of plaque type in the SA and extracranial vertebral artery (EVA) were significantly different between ACS and PCS. The soft plaque thickness of SA in PCS was significantly greater than that in ACS (3.85 ± 1.27 versus 3.51 ± 1.04, P = 0.032).

CONCLUSIONS

Atherosclerotic plaque prevalence and characteristics vary in different segments, sides and between ACS and PCS. These differences should be noted during plaque diagnosis.

Peripheral artery disease: how much inter-leg symmetry? A contrast-enhanced magnetic resonance angiography study

The aim of this observational retrospective study was to qualitatively and quantitatively evaluate the symmetry of atherosclerotic plaques in patients with peripheral artery disease (PAD) undergoing contrast-enhanced magnetic resonance angiography of lower limbs. We retrospectively evaluated the peripheral magnetic resonance angiography of 82 patients considering the iliac, femoral and tibial arteries. Stenosis was scored 0 (none), 1 (<50%), 2 (50%-74%), 3 (75%-99%), and 4 (occluded). Symmetry was quantified as the percentage of bilaterally-diseased arteries and using the inter-leg absolute score difference (0-4). Signs test and Cohen κ were also calculated. Seventy-one (87%) patients had ≥1 bilaterally-diseased artery, and 168 (20%) of 820 artery pairs were bilaterally affected. At least 1 bilateral stenosis was observed from 11% (right internal iliac) to 73% (right superficial femoral). All 10 arteries showed symmetry, none of the inter-leg comparisons being significantly different (P ≥ .100). Cohen κ ranged from 0.208 (common femoral) to 0.533 (internal iliac). This study showed that PAD was symmetrically distributed between the 2 legs, with the internal iliac artery being the most symmetric segment. Symmetry of PAD was quantified in 20%.

Investigation of pelvic symmetry using CAD software

Severe pelvic fractures often prove difficult for surgeons as they require patient-specific surgical treatment plans and customized equipment. Developing virtual patient-specific 3D pelvis models would ease the surgical planning process and enable development of custom fixation plates. This paper aims to examine pelvic symmetry to conclude whether the contralateral side may be used as a reference model for the fractured side of the pelvis. Fourteen subjects with intact pelvises were involved in this study. CT scans of the pelvises were converted to 3D models and the right sides of the pelvises were reflected and aligned with the left sides. A deviation analysis was then performed for each set of models and results showed that the average root mean square (RMS) of values was 1.14 ± 0.26 mm and the average percentage of points below a deviation threshold of ± 2 mm was 91.9 ± 5.55%. The deviation color maps (DCMs) showed that the largest deviations were on the non-articular surfaces. The volume and surface area of each model were also examined and showed no significant differences between left and right sides. These results indicate that the pelvis displays bilateral symmetry and this concept can be used to develop fully intact patient-specific 3D pelvis models for fracture reconstruction using the unfractured contralateral side. Graphical Abstract.

Clinical significance of mirror lesions in lower extremity arterial disease

OBJECTIVE

The aim of this study was to investigate the clinical relevance of bilateral peripheral arterial disease (PAD) patterns.

BACKGROUND

No prior study has evaluated the clinical significance of symmetrical lesion patterns, particularly the coexistence of same-level significant plaques in both lower extremities ("mirror lesions").

METHODS

We conducted a single-facility, primary data analysis involving 225 patients with symptomatic PAD.

RESULTS

Eighty-two percent of the patients had bilateral lesions: 14.2% had femoropopliteal, 38.7% had infrapopliteal, and 27.1% had both femoropopliteal and infrapopliteal lesions. The lesions were found in the exact same arteries bilaterally in 24.9% of the patients, while 26.7% had a local mirror pattern limited to the femoropopliteal (13.7%) or infrapopliteal (12.9%) arteries. Having a lesion in an artery was a risk factor for occlusive disease of the corresponding artery on the other side. Patients presenting with critical limb ischemia (CLI) had a history of resting pain (17%), ulceration/gangrene (13%), or prior amputation (26%) of the contralateral limb. Patients with significant bilateral disease had unilateral false-negative ABI results in 11.6% of the cases. The arterial Doppler study results were unilaterally false-negative in 19.6% and bilaterally false-negative in 2.8% of the patients.

CONCLUSIONS

Patients with known peripheral arterial disease need to have both limbs fully evaluated and monitored, even in cases with negative screening results. Mirror angiographic imaging is common and often accompanied by symptoms of claudication. Unilateral ischemia is a strong risk factor for contralateral disease. Patients with CLI are at high risk for occlusive lesions of the nonindex limb.

Peritoneal Dialysis Is an Independent Factor Associated to Lower Intima Media Thickness in Dialysis Patients Free From Previous Cardiovascular Disease

Carotid intima media thickness (cIMT) displays prognostic value as a marker of cardiovascular risk in dialysis patients. However, few data are available regarding the impact of dialysis modality on cIMT. The aim of this study is to determine whether the modality of dialysis influences cIMT values. We compared 237 peritoneal dialysis (PD) and 451 hemodialysis (HD) patients without previous cardiovascular disease included in NEFRONA, a prospective, observational and multicenter study. This cross sectional study included the determination of cIMT in 6 carotid territories by arterial ultrasound. cIMT was determined in territories without atheroma plaque and averaged. A second analysis was performed using all territories, giving a truncated cIMT value of 1,5 mm to territories presenting with atheroma plaque. Age and plaque presence at baseline were the clinical variables more closely associated to cIMT in dialysis patients. The evaluation of the impact of the modality of dialysis on cIMT showed that PD patients had lower cIMT than HD patients, both in territories with no plaques and when using truncated cIMT values. No differences were found between right and left sides, neither in cIMT or truncated cIMT values. Lineal multivariate analysis adjusted by several clinical variables showed a statistically significant association of PD with a lower cIMT (slope -0.036; SD 0.010). These results were also confirmed when truncated cIMT values were used. We conclude that the modality of dialysis has an impact on cITM. HD patients have greater global cIMT than PD patients, and PD is and independent factor associated with a lower cIMT.

Quantification of carotid plaque lipid content with magnetic resonance T2 mapping in patients undergoing carotid endarterectomy

Background and purpose

Techniques to stratify subgroups of patients with asymptomatic carotid artery disease are urgently needed to guide decisions on optimal treatment. Reliance on estimates of % luminal stenosis has not been effective, perhaps because that approach entirely disregards potentially important information on the pathological process in the wall of the artery.

Methods

Since plaque lipid is a key determinant of plaque behaviour we used a newly validated, high-sensitivity T2-mapping MR technique for a systematic survey of the quantity and distribution of plaque lipid in patients undergoing endarterectomy. Lipid percentage was quantified in 50 carotid endarterectomy patients. Lipid distribution was tested, using two imaging indices (contribution of the largest lipid deposit towards total lipid (LLD %) and a newly-developed LAI ‘lipid aggregation index’).

Results

The bifurcation contained maximal lipid volume. Lipid percentage was higher in symptomatic vs. asymptomatic patients with degree of stenosis (DS ≥ 50%) and in the total cohort (P = 0.013 and P = 0.005, respectively). Both LLD % and LAI was higher in symptomatic patients (P = 0.028 and P = 0.018, respectively), suggesting that for a given plaque lipid volume, coalesced deposits were more likely to be associated with symptomatic events. There was no correlation between plaque volume or lipid content and degree of luminal stenosis measured on ultrasound duplex (r = -0.09, P = 0.53 and r = -0.05, P = 0.75), respectively. However, there was a strong correlation in lipid between left and right carotid arteries (r = 0.5, P <0.0001, respectively).

Conclusions

Plaque lipid content and distribution is associated with symptomatic status of the carotid plaque. Importantly, plaque lipid content was not related to the degree of luminal stenosis assessed by ultrasound. Determination of plaque lipid content may prove useful for stratification of asymptomatic patients, including selection of optimal invasive treatments.

Carotid Artery Disease - Left vs Right

Stroke is a common cause of adult disability and the third cause of death in Western European countries. Carotid disease is a well-known risk factor for ischemic stroke, and this relationship is established. However, only a minority of the population with atherosclerosis will have a stroke.

The aim of these paper is to establish the relation between carotid atherosclerosis and first ischemic stroke. We performed an observational study, including 159 patients with carotid atherosclerosis. Our patients were examined with carotid ultrasound examination and cranio-cerebral computed tomography. We excluded patient with other cause of cerebral ischemia such atrial fibrillation, myocardial infarction, arterial dissection, vasculopathy, neoplasia. We also excluded any kind of transient cerebral ischemia, because of heterogeneity and poor medical documentation.

Despite our efforts to treat this condition, carotid disease remains a powerful risk factor for ischemic stroke.

Determination of Bilateral Symmetry of Carotid Artery Structure and Function in Children and Adolescents

We compared the symmetry of carotid arteries in youth with high-resolution ultrasound. Participants (n=230 (121 females),13.8 ± 2.9 years old) were assessed for: intima media thickness (cIMT), lumen diameter (cLD), incremental elastic modulus (cIEM), diameter compliance (cDC), cross-sectional compliance (cCSC), diameter distensibility (cDD), and cross-sectional distensibility (cCSD). No significant differences (P >0.05 all) were found for cIMT (0.49 ± 0.09 mm vs. 0.49 ± 0.08 mm), cIEM (1095 ± 382 mmHg vs. 1116 ± 346mmHg), cDC (0.01 ± 0.0 mm/mmHg vs. 0.01 ± 0.0 mm/mmHg), cCSC (0.01 ± 0.001/mmHg vs. 0.01 ± 0.001/mmHg), cDD (14.0 ± 3.16% vs. 13.7 ± 3.18%), and cCSD (30.1 ± 7.37% vs. 29.4 ± 7.36%). Significant differences were found for cLD (6.06 ± 0.62 mm vs. 6.33 ± 0.64 mm, P <0.001). These data suggest that these values may be used interchangeably if one side is inaccessible.

The Dual Role of Cerebral Autoregulation and Collateral Flow in the Circle of Willis After Major Vessel Occlusion

OBJECTIVE

Ischaemic stroke is a leading cause of death and disability. Autoregulation and collateral blood flow through the circle of Willis both play a role in preventing tissue infarction. To investigate the interaction of these mechanisms a one-dimensional steady-state model of the cerebral arterial network was created.

METHODS

Structural variants of the circle of Willis that present particular risk of stroke were recreated by using a network model coupled with: 1) a steady-state physiological model of cerebral autoregulation; and 2) one wherein the cerebral vascular bed was modeled as a passive resistance. Simulations were performed in various conditions of internal carotid and vertebral artery occlusion.

RESULTS

Collateral flow alone is unable to ensure adequate blood flow ([Formula: see text] normal flow) to the cerebral arteries in several common variants during internal carotid artery occlusion. However, compared to a passive model, cerebral autoregulation is better able to exploit available collateral flow and maintain flows within [Formula: see text] of baseline. This is true for nearly all configurations.

CONCLUSION

Hence, autoregulation is a crucial facilitator of collateral flow through the circle of Willis.

SIGNIFICANCE

Impairment of this response during ischemia will severely impact cerebral blood flows and tissue survival, and hence, autoregulation should be monitored in this situation.

Coronary Risk Stratification in Patients with Ischemic Stroke or Transient Ischemic Stroke Attack

Background

The risk of coronary artery disease (CAD) is traditionally considered high in patients who had an ischemic stroke or a transient ischemic attack (TIA). However, few studies have specifically assessed the absolute risk of coronary events in those patients and predictors of such events are not well known.

Summary of review

The overall risks of myocardial infarction and nonstroke vascular death are each around 2% per year. However, those risks are only about 1% per year in patients without CAD (i.e. the only ones who are likely to benefit from specific additional strategies). The prevalence of asymptomatic CAD ranges from 15% to 60%. Although potentially higher, the risk of CAD in patients with stroke/TIA related to atherosclerosis also seems to vary widely depending on the extent of the disease. Given the relatively low CAD risk, a simple systematic reinforcement of medical treatment in all patients may be not relevant. Up to now, there have been only limited ways to stratify the CAD risk in stroke/TIA patients. High-risk patients may be identified using the traditional cardiac scoring systems, but their validity has never been specifically assessed in stroke populations. The relative influence of traditional risk factors may be altered after a first vascular event. Stroke patients could also be screened for asymptomatic CAD. However, there is no simple and valid screening test for asymptomatic CAD that could be applied to all patients. Finally, there is still uncertainty about the potential benefits of treating asymptomatic CAD. Therefore, should the identification of patients with asymptomatic CAD requiring revascularization become feasible, the relevance of this strategy would remain to be evaluated by a randomized clinical trial.

Conclusion

The absolute risk of CAD in stroke/TIA patients is moderately high. More research is needed to identify high risk patients who could benefit from specific strategies.

Distribution of alkaline phosphatase, osteopontin, RANK ligand and osteoprotegerin in calcified human carotid atheroma

Ectopic vascular calcification is a significant component of atherosclerotic disease. Osteopontin (OPN), Osteoprotegerin (OPG), Receptor Activator of NFκB Ligand (RANKL), and alkaline phosphatase (ALP) are each thought to play central roles in the calcification or demineralization of atherosclerotic lesions. Abnormalities in the balance of these proteins may lead to perturbations in bone remodeling and arterial calcification. The purpose of this study was to measure the distribution of these proteins in human carotid lesions and to elucidate possible mechanism(s) whereby they control the deposition or depletion of arterial calcification. Thirty-three patients who had undergone carotid endarterectomy (CEA) within the previous 18 months and 11 control patients were enrolled. CEA specimens were analyzed by EBCT for calcification content in terms of Agatston (AGAT) and Volume scores. CEA specimens were then cut into 5 mm segments which were homogenized and extracted. Extracts were analyzed for tissue levels of calcium, phosphorus, ALP, OPN, RANKL, and OPG. Fasting blood samples were analyzed for the same components. In CEA tissue segments, the calcification levels (CHA AGAT) were inversely associated with the levels of OPG (r = -0.432/-0.579, p < 0.05) and positively associated with the levels of RANKL (r = 0.332/0.415, p < 0.05). In turn, the tissue levels of OPG were associated with homologous serum levels of OPG (r = 0.820/0.389, p < 0.001), and the tissue levels of RANKL were associated with the serum levels of homologous RANKL (r = 0.739/0.666, p < 0.0001). This study suggests that serum levels of OPG and RANKL may be useful biomarkers for estimating the degree of calcification in carotid atherosclerotic lesions.

Correlation of dental pulp stones, carotid artery and renal calcifications using digital panoramic radiography and ultrasonography

Background:

The human tissues continuously undergo modification as deposition of calcium (CA) salts either in an organized or disorganized pattern. The latter pattern usually occurs in the soft tissues such as in arteries, brain, kidneys, lungs, and dental pulp. The purpose of this study is to evaluate the presence of pulp calcification and carotid artery calcification (CDC) as a marker for renal calcification and altered serum biomarkers such as serum CA, phosphorus (P), and alkaline phosphatase (ALP).

Materials and Methods:

Digital panoramic radiographs of 50 patients with the presence of pulp stones and suspected CAC were subjected to carotid artery and renal ultrasonography (USG) examination for the presence of vascular calcification and also to evaluate the alterations in serum CA, P, and ALP levels. Data were analyzed statistically using Chi-square test.

Results:

Panoramic radiographs of 50 patients showed 88.28% of teeth with the presence of pulp stones stones and 91% carotid arteries with calcification. The sensitivity of panoramic radiograph was greater than that of USG (93.67%), but the specificity of USG was more than the panoramic radiograph (44.44%) in detecting CAC. The prevalence rate of renal calcification on USG was 92%. The statistical difference between the patients with or without alteration in serum Ca levels was not significant (χ² = 0.581 and P = 0.446). On comparison of serum P and ALP, the difference was found to be statistically significant.

Conclusion:

Presence of pulp stones and CAC's on panoramic radiograph have remarkably proved to establish the chances of renal artery calcification associated with alterations in serum CA levels.

Association between extra- and intracranial calcifications of the internal carotid artery: a CBCT imaging study

OBJECTIVES

This study aimed to evaluate the association between the extracranial and intracranial calcification depiction of the internal carotid artery (ICA), incidentally found in CBCT examinations in adults, and to discuss the conspicuous clinical implications.

METHODS

Out of a series of 1085 CBCT examinations, 705 CBCT scans were selected according to pre-defined criteria. The extra- and intracranial calcifications depicted along the course of the ICA were documented according to a comprehensive set of descriptive criteria.

RESULTS

In total, 799 findings were detected, 60.1% (n = 480) were intracranially and 39.9% (n = 319) were extracranially allocated. The χ(2) test showed associations between all variables (p < 0.001). Also, most of the combinations of variables showed statistically significant results in the McNemar's test (p < 0.001).

CONCLUSIONS

We found that a significant correlation exists between extra- and intracranial calcifications of the ICA. It is clear that in cases of the presence of a calcification in the ICA extracranially, the artery's intracranial portion has an increased risk of showing the same findings. CBCT imaging is widely used as a diagnostic tool, thus, our results contribute to the identification of a subgroup of patients who should undergo further medical evaluation of the atherosclerosis of the ICAs.

Red cell distribution width and carotid atherosclerosis progression. The Tromsø Study

Red cell distribution width (RDW), a measure of the size variability of circulating erythrocytes, is associated with cardiovascular morbidity and mortality. We aimed to investigate whether RDW was associated with progression of atherosclerotic plaques in subjects recruited from the general population. Baseline characteristics, including RDW, were collected from 4677 participants in the fourth survey of the Tromsø Study conducted in 1994/95. Prevalence of carotid plaques and total plaque area (TPA) were assessed by ultrasonographic imaging at baseline and after seven years of follow-up. Generalised linear models were used to analyse change in TPA across tertiles of RDW. Change in TPA was significantly higher across tertiles of RDW in crude analysis and in multivariable analysis adjusted for cardiovascular risk factors. The mean change in TPA increased from 5.6 mm² (4.9-6.4) in tertile 1 (RDW ≤ 12.6 %) to 6.7 mm² (5.9-7.6) in tertile 3 (RDW ≥ 13.3) in multivariable analysis adjusted for body mass index, total cholesterol, HDL cholesterol, systolic blood pressure, self-reported diabetes, smoking status, platelet count, white blood cell count, and hs-CRP levels (p for trend 0.003). A 1 % increase in RDW was associated with 0.6 mm² (0.1-1.2) increase in TPA in multivariable analysis (p=0.03). RDW was associated with progression of atherosclerosis after adjustments for traditional atherosclerotic risk factors. Our findings suggest that the link between RDW and cardiovascular morbidity and mortality may be explained by atherosclerosis.

3D reconstruction of a carotid bifurcation from 2D transversal ultrasound images

Visualizing and analyzing the morphological structure of carotid bifurcations are important for understanding the etiology of carotid atherosclerosis, which is a major cause of stroke and transient ischemic attack. For delineation of vasculatures in the carotid artery, ultrasound examinations have been widely employed because of a noninvasive procedure without ionizing radiation. However, conventional 2D ultrasound imaging has technical limitations in observing the complicated 3D shapes and asymmetric vasodilation of bifurcations. This study aims to propose image-processing techniques for better 3D reconstruction of a carotid bifurcation in a rat by using 2D cross-sectional ultrasound images. A high-resolution ultrasound imaging system with a probe centered at 40MHz was employed to obtain 2D transversal images. The lumen boundaries in each transverse ultrasound image were detected by using three different techniques; an ellipse-fitting, a correlation mapping to visualize the decorrelation of blood flow, and the ellipse-fitting on the correlation map. When the results are compared, the third technique provides relatively good boundary extraction. The incomplete boundaries of arterial lumen caused by acoustic artifacts are somewhat resolved by adopting the correlation mapping and the distortion in the boundary detection near the bifurcation apex was largely reduced by using the ellipse-fitting technique. The 3D lumen geometry of a carotid artery was obtained by volumetric rendering of several 2D slices. For the 3D vasodilatation of the carotid bifurcation, lumen geometries at the contraction and expansion states were simultaneously depicted at various view angles. The present 3D reconstruction methods would be useful for efficient extraction and construction of the 3D lumen geometries of carotid bifurcations from 2D ultrasound images.

Atherosclerotic Plaque in the Left Carotid Artery Is More Vulnerable Than in the Right

Background and Purpose—

Ischemic stroke is more often diagnosed in the left hemisphere than in the right. It is unknown whether this asymmetrical prevalence relates to differences in carotid atherosclerosis. We compared atherosclerotic plaque prevalence, severity, and composition between left and right carotid arteries.

Methods—

In a population-based cohort, carotid MRI scanning was performed in 1414 stroke-free participants (≥45 years). Using a multisequence MRI protocol, we assessed the prevalence, stenosis, and thickness of the plaque and its predominant component (ie, lipid core, intraplaque hemorrhage, calcification, or fibrous tissue in each carotid artery). Differences between left and right side were tested using paired t tests, McNemar test and Generalized Estimating Equation analyses.

Results—

The majority (85%) of the participants had bilateral carotid plaques. Unilateral plaques were twice more prevalent on the left than on the right side (67% versus 33%; P <0.001). Plaque thickness was also greater on the left (3.1±1.2 versus 2.9±1.3 mm; P <0.001); degree of stenosis did not differ. Intraplaque hemorrhage and fibrous tissue were more prevalent on the left (9.1 versus 5.9%; P <0.001 and 45.0 versus 38.5%; P <0.001), whereas calcification occurred more often on the right (37.4 versus 31.6% at the left; P <0.001). Lipid was equally distributed.

Conclusions—

Carotid atherosclerotic plaque size and composition are not symmetrically distributed. Predominance of intraplaque hemorrhage in left-sided carotid plaques suggests a greater vulnerability as opposed to right-sided plaques, which are more calcified and therefore considered more stable.

Distribution of calcification in carotid endarterectomy tissues: Comparison of micro-computed tomography imaging with histology

Background:

Calcification in atherosclerotic plaques has been viewed as a marker of plaque stability, but whether calcification accumulates in specific anatomic sites in the carotid artery is unknown. We determined the burden and distribution of calcified plaque in carotid endarterectomy (CEA) tissues.

Methods:

A total of 22 CEA tissues were imaged with high-resolution micro-computed tomography (micro-CT). Total plaque burden and total calcium score using the Agatston method were quantified. The Agatston score (AS) was also normalized for tissue size. Plaque and calcium distribution were analyzed separately for three CEA regions: common segment (CS), bulb segment (BS), and internal/external segments (IES).

Results:

The average CEA tissue length was 40.83 (interquartile range [IQR] 33.31–42.41) mm with total plaque burden of 103.45 (IQR: 78.84–156.81) mm3 and total AS of 38.58 (IQR 11.59–89.97). Total plaque volume was 21.02 (IQR: 14.47–25.42) mm3 in the CS, 37.89 (22.59–48.32) mm3 in the BS, and 54.05 (36.87–74.52) mm3 in the IES. Of the 22 tissues, 15 had no calcium in the CS compared with three in the bulb and two in the IES. Normalized calcified plaque was most prevalent in the BS, the IES and was least prevalent in the CS. The overall correlation of calcification between histology sections and matched micro-CT images was 0.86 ( p<0.001).

Conclusions:

Calcified plaque is heterogeneously distributed in CEA tissues with most in the bulb and IES regions. The amount of calcification in micro-CT slices shows a high correlation with matched histology sections.

Asymmetric radial expansion and contraction of rat carotid artery observed using a high-resolution ultrasound imaging system

The geometry of carotid artery bifurcation is of high clinical interest because it determines the characteristics of blood flow that is closely related to the formation and development of atherosclerotic plaque. However, information on the dynamic changes in the vessel wall of carotid artery bifurcation during a pulsatile cycle is limited. This pilot study investigated the cyclic changes in carotid artery geometry caused by blood flow pulsation in rats. A high-resolution ultrasound imaging system with a broadband scanhead centered at 40 MHz was used to obtain longitudinal images of the rat carotid artery. A high frame rate retrospective B-scan imaging technique based on the use of electrocardiogram to trigger signal acquisition was used to examine precisely the fast arterial wall motion. Two-dimensional geometry data obtained from nine rats showed that the rat carotid artery asymmetrically contracts and dilates during each cardiac cycle. Systolic/diastolic vessel diameters near the upstream and downstream regions from the bifurcation were 0.976 ± 0.011/0.825 ± 0.015 mm and 0.766 ± 0.015/0.650 ± 0.016 mm, respectively. Their posterior/anterior wall displacement ratios in the radial direction were 41.0 ± 14.9% and 2.9 ± 1.6%, respectively. These results indicate that in the vicinity of bifurcation, the carotid artery favorably expands to the anterior side during the systolic phase. This phenomenon was observed to be more prominent in the downstream region near the bifurcation. The cyclic variation pattern in wall movement varies depending on the measurement site, which shows different patterns at far upstream and downstream of the bifurcation. The asymmetric radial expansion and contraction of the rat carotid artery observed in this study may be useful in studying the hemodynamic etiology of cardiovascular diseases because the pulsatile changes in vessel geometry may affect the local hemodynamics that determines the spatial distribution of wall shear stress, one of important cardiovascular risk factors. Further systematic study is needed to clarify the effects of wall elasticity, branch angle and vessel diameter ratio on the asymmetric wall motion of carotid artery bifurcation.

The Effect of Lipid Modification on Peripheral Artery Disease after Endovascular Intervention Trial (ELIMIT)

METHODS

A total of 102 patients were randomized to either mono-therapy with simvastatin (40 mg daily) or triple-therapy with simvastatin (40 mg daily), extended-release niacin (1500 mg daily), and ezetimibe (10 mg daily). MRI was performed at baseline and 6, 12, and 24 months. SFA wall, lumen, and total vessel volumes were quantified. MRI-derived SFA parameters and lipids were analyzed with multilevel models and nonparametric tests, respectively.

RESULTS

Baseline characteristics did not differ between mono and triple-therapy groups, except for ethnicity (p = 0.02). SFA wall, lumen, and total vessel volumes increased non-significantly for both groups between baseline and 24-months. Non-high-density lipoprotein cholesterol was significantly reduced at 12 months with triple-therapy compared with mono-therapy (p = 0.01).

CONCLUSION

No significant differences were observed between mono-therapy using simvastatin and triple-therapy with simvastatin, extended-release niacin, and ezetimibe for 24-month changes in SFA wall, lumen, and total vessel volumes.

CLINICAL TRIAL REGISTRATION INFORMATION

NCT00687076; Link: http://clinicaltrials.gov/ct2/show/NCT00687076.

Association of ultrasonic texture and echodensity features between sides in patients with bilateral carotid atherosclerosis

OBJECTIVES

Our objective was to estimate the correlation of echodensity and textural features, using ultrasound and digital image analysis, between plaques in patients with bilateral carotid stenosis.

DESIGN

Cross-sectional observational study.

METHODS

Patients undergoing carotid endarterectomy were recruited from Vascular Surgery at the Royal Victoria and Jewish General hospitals in Montreal, Canada. Bilateral pre-operative carotid ultrasound and digital image analysis was performed to extract echodensity and textural features using a commercially available Plaque Texture Analysis software (LifeQMedical Ltd). Principal component analysis (PCA) was performed. Partial correlation coefficients for PCA and individual imaging variables between surgical and contralateral plaques were calculated with adjustment for age, sex, contralateral stenosis, and statin use.

RESULTS

In the whole group (n = 104), the six identified PCA variables and 42/50 individual imaging variables were moderately correlated (r = .211-.641). Correlations between sides were increased in patients with ≥50% contralateral stenosis and symptomatic patients.

CONCLUSION

Textural and echodensity features of carotid plaques were similar between two sides in patients with bilateral stenosis, supporting the notion that plaque instability is determined by systemic factors. Patients with unstable features of one plaque should perhaps be monitored more closely or treated more aggressively for their contralateral stenosis, particularly if this is hemodynamically significant.

Cross-sectional, prospective study of MRI reproducibility in the assessment of plaque burden of the carotid arteries and aorta

Introduction

This cross sectional study was conducted to test reproducibility of analysis of MRI parameters in carotids and thoracic descending aorta (TOA), evaluate the correlation of plaque burden and associations with subject age and gender.

Methods

Three hundred subjects, with cardiovascular risk factors, underwent a black blood MRI of both carotids and TOA. Mean wall area, wall thickness, lumen area, total vessel area and wall area/total vessel area (WA/TVA) ratio were manually measured. Inter-reader and intra-reader-reproducibility was tested on 187 and 20 randomly chosen subjects respectively.

Results

The intra-observer-reproducibility for the analysis was high (Intraclass-Correlation-Coefficients (ICC’s >0.8), except mean WA/TVA ratio of TOA. Similarly, the inter-observer reproducibility was acceptable (ICC’s >0.7 for mean wall area, lumen area and total vessel area). MRI parameters in aorta and carotids increased with age for both sexes (p<0.001). Except for mean wall thickness of TOA and WA/TVA ratio, MRI parameters were significantly higher in males than in females. All MRI measurements except the mean wall thickness and WA/TVA ratio were highly reproducible. There was good correlation for mean wall area between carotids and aorta compatible with the systemic nature of atherosclerosis. Similar to clinical presentation of cardiovascular diseases we found greater values in most MRI parameters (except for WA/TVA ratio) in males than in females and with increasing age.

Conclusions

These data suggest that analysis of most MRI measurements of plaque burden is reproducible and that there is correlation between plaque burden between carotids and aorta validating the systemic distribution of the disease.

Quantitative segmentation of principal carotid atherosclerotic lesion components by feature space analysis based on multicontrast MRI at 1.5 T

The purpose of this paper is to evaluate the capability of feature space analysis (FSA) for quantifying the relative volumes of principal components (thrombus, calcification, fibrous, normal intima, and lipid) of atherosclerotic plaque tissue in multicontrast magnetic resonance images (mc-MRI) acquired in a setup resembling clinical conditions ex vivo. Utilizing endogenous contrast, proton density, T1-weighted, and T2-weighted images were acquired for 13 carotid endarterectomy (CEA) tissues under near-clinical conditions (human 1.5 T GE Excite scanner with sequence parameters comparable to an in vivo acquisition). An FSA algorithm was utilized to segment and quantify the principal components of atherosclerotic plaques. Pilot in vivo mc-MRI images were analyzed in the same way as the ex vivo images for exploring the possible adaptation of this technique to in vivo imaging. Relative abundance of principal plaque components in CEA tissues as determined by mc-MRI/FSA were compared to those measured by histology. Mean differences +/- standard deviations were 5.8 +/- 4.1% for thrombus, 1.5 +/-1.4 % for calcification, 4.0 +/-2.8% for fibrous, 8.2 +/- 10% for normal intima, and 2.4 +/- 2.2% for lipid. Reasonable quantitative agreement between the classification results obtained with FSA and histological data was obtained for near-clinical imaging conditions. Combination of mc-MRI and FSA may have an application for determining atherosclerotic lesion composition and monitoring treatment in vivo.

Atherothrombosis and plaque heterology: different location or a unique disease?

Formation of unstable plaques frequently results in atherothrombosis, the major cause for ischaemic stroke, myocardial infarction and peripheral arterial disease. Patients who have symptomatic thrombosis in one vascular bed are at increased risk of disease in other beds. However, the development of the disease in carotid, coronary and peripheral arteries may have different pathophysiology suggesting that more complex treatment protocols may have to be designed to reduce plaque development at different locations. In this review we describe the known risk factors, compare the developmental features of coronary and carotid plaque development and determine their association with end-point ischaemic events. Differences are also seen in the genetic contribution to plaque development as well as in the deregulation of gene and protein expression and cellular signal transduction activity of active cells in regions susceptible to thrombosis. Differences between carotid and coronary artery plaque development might help to explain the differences in anatomopathological appearance and risk of rupture.

Multidetector-row CT angiography in the study of atherosclerotic carotid arteries

Pathologies of the carotid arteries, and in particular atherosclerosis, are now an important medical problem. Stroke is the third leading cause of severe disability in the Western World leading to millions of deaths every year. Extracranial carotid atherosclerotic disease is the major risk factor for stroke. In years, with the advent of multidetector-row CT (MDCT) scanners and the use of specific angiographic protocols (MDCTA), CT imaging of the carotid arteries has become increasingly effective. In addition, the volume data obtained can be further rendered to generate high-quality two-dimensional and three-dimensional images. The purpose of this study was to review the atherosclerotic carotid arteries, their complications and how MDCTA depicts them, underlining the benefits and pitfalls of this diagnostic technique.

Combined low-dose pioglitazone, flutamide, and metformin for women with androgen excess

CONTEXT AND OBJECTIVE

One of the treatments for hyperinsulinemic hyperandrogenism in nonobese women is combined androgen receptor blockade (with flutamide; Flu), insulin sensitization (with metformin; Met) plus an estroprogestagen contraceptive. We tested whether adding low-dose pioglitazone (Pio; 7.5 mg/d) confers more benefit.

SETTING

The study was conducted at a university hospital.

STUDY POPULATION AND DESIGN

This double-blind study enrolled 38 young women with hyperinsulinemic hyperandrogenism [mean body mass index (BMI) 24 kg/m(2)], all of whom started on Flu (62.5 mg/d) and Met (850 mg/d) plus a transdermal estroprogestagen, each for 21 of 28 d over 6 months. Patients were randomly assigned to receive, in addition, placebo (n=19) or Pio (n=19; 7.5 mg/d) for the same 21 of 28 d over 6 months.

MAIN OUTCOMES

BMI, waist to hip ratio, hirsutism score, fasting endocrine-metabolic markers, body composition, abdominal fat (visceral vs. sc), and carotid intima-media thickness were measured at study start and after 6 months.

RESULTS

PioFluMet reduced intima-media thickness more than FluMet and lowered glucose, IGF-I, and C-reactive protein more as well as the ratio of low-density lipoprotein to high-density lipoprotein cholesterol and the ratio of neutrophils to lymphocytes. PioFluMet treatment was followed by a leaner body composition and a loss of visceral fat (both P < 0.001). In the total group, the changes included not only decreases in waist to hip ratio, hirsutism score, and testosterone (all P < 0.001) but also minor drops in alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transpeptidase, and lactate dehydrogenase (all P < 0.005), indicating absence of hepatotoxicity; BMI remained unchanged. Clinical side effects were not detected.

CONCLUSION

In this proof-of-concept study, addition of Pio to FluMet plus an estroprogestagen led to improvements in the endocrine-metabolic condition, in low-grade inflammation, in total and visceral adiposity, and in markers of cardiovascular health.

Three-dimensional Black-Blood MR Imaging of Carotid Arteries with Segmented Steady-State Free Precession: Initial Experience

This HIPAA-compliant study had institutional review board approval. Informed consent was obtained. The purpose was to prospectively evaluate a segmented three-dimensional (3D) double inversion recovery (DIR)-prepared steady-state free precession (SSFP) magnetic resonance (MR) imaging sequence for fast high-spatial-resolution black-blood carotid arterial wall imaging. Carotid wall-lumen contrast-to-noise ratio (CNR) obtained with this sequence was compared with those obtained with two-dimensional (2D) single- and multisection black-blood fast spin-echo (SE) sequences. MR imaging of both carotid artery bifurcations over 3 cm of transverse coverage was performed in eight volunteers (seven men, one woman; age range, 26-56 years) with no known history of carotid artery disease. Adjusted for section thickness and imaging time per section, higher effective mean CNR was achieved with segmented 3D DIR-prepared SSFP than with single-section 2D DIR-prepared fast SE or multisection 2D saturation-band fast SE (P < .05). Segmented 3D DIR-prepared SSFP enables black-blood carotid arterial wall MR imaging with contiguous thin-section coverage and greater imaging speed and effective CNR than conventional 2D fast SE techniques.

Short-term tracking of atherosclerosis in operated and unoperated human carotid arteries by high resolution magnetic resonance imaging

INTRODUCTION

A previous study demonstrated the efficacy of a phospholipid (PL) complexed with a protein (apoAI Milano) in causing 4.6% regression of atheroma volume as assessed by intravascular ultrasonography (IVUS) in a group of 47 patients with carotid atherosclerosis. The results of this study raised the question of whether the phospholipid alone could produce a similar effect.

METHODS

To answer this question a trial of 39 subjects at five sites was designed. Patients with > 15% stenosis of at least one carotid artery as determined by US underwent intravenous PL (200 mg/kg) or placebo infusions weekly for 8 weeks. The wall/outer wall ratio, percent lipid-rich/necrotic core, and percent calcification were measured as a proportion of the vessel wall by magnetic resonance imaging (MRI) at 0, 4, 8, and 14 weeks.

RESULTS

The substudy of seven of these patients evaluated at our site allowed comparison of the dimensions of five unoperated-unoperated carotid pairs and two operated-unoperated pairs. In patient 1, MRI measurements on unoperated left and unoperated right carotids tracked almost identically over the 14-week study. Both carotids showed similar increases in the volumes of the total wall (+61% vs. 56%), the normal wall (+51% vs. 49%), and plaque (+99% vs. 85%). Both carotids showed similar decreases in lumen volume (-11% vs. -17%). The other four unoperated-unoperated carotid pairs showed dimensional changes over 14 weeks similar to those of patient 1. In patient 2, who underwent left endarterectomy, the operated carotid had a total artery volume of 2300 mm(3), about twofold greater than the unoperated carotid (1100 mm(3)). Operated and unoperated carotid measurements tracked in parallel. The unoperated carotid had volume increases of 25% (+200 mm(3)) in total wall, +19% (+100 mm(3)) in normal wall, and 43% (+75 mm(3)) in plaque. The operated carotid lumen showed no significant changes. Patient 7, who also underwent left endarterectomy, exhibited carotid changes similar to those of patient 2.

CONCLUSIONS

Individual unoperated carotid pairs have volumes that track almost identically. In unilateral operated carotid pairs, the operated artery has 1.5- to 2.0-fold greater volume than unoperated carotids. In each of our two unilaterally operated patients, the operated carotid had decreased plaque volume (-3%, -58%), whereas the unoperated carotid had increased plaque volume (+43%, +7%). Among the five unoperated patients, one pair had 85%/99% increase in plaque volume; one pair had -15%/-10% decrease; and the other three pairs had intermediate changes. This study provides additional support to the view that unoperated human carotid arteries are bilaterally symmetrical.

Risk of Coronary and Other Nonstroke Vascular Death in Relation to the Presence and Extent of Atherosclerotic Disease at the Carotid Bifurcation

BACKGROUND AND PURPOSE

It has been proposed that purely unilateral carotid stenosis is due mainly to local hemodynamic factors, whereas more diffuse disease reflects a systemic as well as a local predisposition and should therefore be associated with higher rates of arterial disease in the other territories. However, few studies have tested this hypothesis.

METHODS

We studied angiograms from 2741 patients with a recently symptomatic carotid stenosis from the European Carotid Surgery Trial and categorized them as showing purely unilateral disease (no convincing plaque in the contralateral carotid artery) or bilateral disease. We related the presence and extent of plaque at both bifurcations to the prevalence of past atherothrombotic disease in other arterial territories and the risk of future nonstroke vascular events.

RESULTS

The degree of symptomatic carotid stenosis was unrelated to either the prevalence of symptomatic arterial disease in other territories at baseline or to the risk of nonstroke vascular death during follow-up, whereas there were strong associations with the presence of bilateral carotid disease. In multivariate analyses, bilateral carotid disease (n=2076) was associated with previous myocardial infarction (odds ratio [OR]=1.7; 95% CI, 1.2 to 2.4) or peripheral vascular disease (OR=1.5; 95% CI, 1.2 to 2.0) and with subsequent nonstroke vascular death (hazard ratio=2.0; 95% CI, 1.5 to 2.6). The 5-year risk of nonstroke vascular death ranged from 2.7% (95% CI, 1.5% to 4.6%) in patients with no history of coronary or peripheral arterial disease at baseline and purely unilateral carotid disease to 21.4% (95% CI, 17.6% to 26.1%) in those with bilateral carotid disease and a history of either coronary or peripheral arterial disease (P<0.0001).

CONCLUSIONS

Bilateral carotid disease is associated with higher rates of symptomatic arterial disease in other territories, suggesting a systemic predisposition to atherosclerosis and hence, the need for more aggressive preventive treatment, whereas purely unilateral carotid disease indicates a mainly local hemodynamic etiology.

High Incidence of Infarction in the Left Cerebral Hemisphere Among Young Adults

We hypothesized that left cerebral hemisphere infarction is more frequent than right hemisphere infarction among young adults. Furthermore, we aimed to evaluate possible causes for this asymmetry. Cases were found by computer search from hospital registries at each of the 5 acute-care hospitals in a well-defined population in Hordaland County, western Norway. Important parameters used in the analysis were derived from the patient records. A total of 98 patients had left hemisphere infarctions, and 70 patients had right hemisphere infarctions (P = .037). This difference was due mostly to the higher incidence of infarction in the left middle cerebral artery (MCA) territory compared with the right MCA territory among the male subjects (P = .016). Lacunar infarction was equally distributed, whereas nonlacunar infarction was more frequent in the left MCA territory among the men (P = .016). A high frequency of left MCA infarctions may be associated with more frequent atherosclerosis in the left carotid artery, lateralization of cortical functions, or both in young adults.

Polycystic ovaries after precocious pubarche: relation to prenatal growth

BACKGROUND

In 1998, we revealed a sequence departing from prenatal growth restraint in girls and evolving, through precocious pubarche (PP) in mid-childhood, towards anovulatory and hyperinsulinaemic hyperandrogenism. The latter condition fulfilled the criteria for the diagnosis of polycystic ovary syndrome (PCOS), which was then defined independently of the presence of polycystic ovaries (PCOs). Since 2003, the diagnosis of PCOS has been extended by adding PCO as an alternative criterion. We verified longitudinally over 28 +or- 2 years the prevalence of PCO and its potential relationship to growth before birth in a group of post-PP women (n=14, mean age=28 years; body mass index=24.3 kg/m2) belonging to the original cohort of 35 girls in whom the PP-PCOS sequence was described.

METHODS

Endocrine-metabolic variables, body composition (by dual-energy X-ray absorptiometry), carotid intima-media thickness (IMT) and ovarian morphology by transvaginal ultrasonography were assessed in all women.

RESULTS

Post-PP women with a birthweight (BW) in the lowest quartile, when compared with post-PP women with a higher BW, had smaller ovaries (mean volume=4.0 versus 9.0 ml; P=0.004) and a much lower prevalence of PCO (0 versus 67%; P=0.006). The remaining variables were similar between BW subgroups.

CONCLUSIONS

The presence of a PCO morphology in women with a PP history was found to relate to prenatal growth. It would be of interest to verify whether a similar relationship exists in anovulatory and/or hyperandrogenic women without PP history.

Comparison of symptomatic and asymptomatic atherosclerotic carotid plaque features with in vivo MR imaging

PURPOSE

To retrospectively determine if in vivo magnetic resonance (MR) imaging can simultaneously depict differences between symptomatic and asymptomatic carotid atherosclerotic plaque.

MATERIALS AND METHODS

Institutional review board approval and informed consent were obtained for this HIPAA-compliant study. Twenty-three patients (21 men, two women; mean age, 66.1 years +/- 11.0 [standard deviation]) with unilateral symptomatic carotid disease underwent 1.5-T time-of-flight MR angiography and 1.5-T T1-, intermediate-, and T2-weighted MR imaging. Both carotid arteries were reviewed. One observer recorded quantitative and morphologic information, which included measurement of the area of the lumen, artery wall, and main plaque components; fibrous cap status (thick, thin, or ruptured); American Heart Association (AHA) lesion type (types I-VIII); and location (juxtaluminal vs intraplaque) and type of hemorrhage. Plaques associated with neurologic symptoms and asymptomatic plaques were compared with Wilcoxon signed rank and McNemar tests.

RESULTS

Compared with asymptomatic plaques, symptomatic plaques had a higher incidence of fibrous cap rupture (P = .007), juxtaluminal hemorrhage or thrombus (P = .039), type I hemorrhage (P = .021), and complicated AHA type VI lesions (P = .004) and a lower incidence of uncomplicated AHA type IV and V lesions (P = .005). Symptomatic plaques also had larger hemorrhage (P = .003) and loose matrix (P = .014) areas and a smaller lumen area (P = .008). No significant differences between symptomatic and asymptomatic plaques were found for quantitative measurements of the lipid-rich necrotic core, calcification, and the vessel wall or for the occurrence of intraplaque hemorrhage or type II hemorrhage.

CONCLUSION

This study revealed significant differences between symptomatic and asymptomatic plaques in the same patient.

Quantitation and localization of matrix metalloproteinases and their inhibitors in human carotid endarterectomy tissues

BACKGROUND

Matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) play a central role in arterial wall remodeling, affecting stability of fibrous caps covering atherosclerotic plaques. The objective of this study was to determine the spatial distribution of TIMP mass and MMP mass and activity of carotid endarterectomy (CEA) tissues and relate it to the distribution of atherosclerotic lesions.

METHODS AND RESULTS

Fresh CEA tissues were imaged by multicontrast MRI to generate 3D reconstructions. Tissue segments were cut transversely from the common, bifurcation, internal, and external regions. Segments were subjected to total protein extractions and analyzed by ELISA for MMP-2 and -9 and TIMP-1 and -2 mass and by zymography for gelatinase activity. Segments at or near the bifurcation with highly calcified lesions contained higher MMP levels and activity than segments distant from the bifurcation; highly fibrotic or necrotic plaque contained lower MMP levels and activity and higher TIMP levels. Fatty streak, fibroatheroma with hemorrhage and calcification, and fully occluded lesions were enriched in MMP-2, MMP-9, and TIMP-1 and TIMP-2, respectively.

CONCLUSIONS

The spatial distribution of MMPs and TIMPs in carotid atherosclerotic lesions is highly heterogeneous, reflecting lesion location, size, and composition. This study provides the first semi-quantitative maps of differential distribution of MMPs and TIMPs over atherosclerotic plaques.

Quantification of Calcification in Atherosclerotic Lesions

Calcification can be deposited throughout the vasculature in several forms of calcium phosphate, including calcium hydroxyapatite (CHA). Calcium accumulation in arteries by mineralization and calcium loss from bone by osteoporosis often coexist, and vascular calcification may share common mechanisms with bone remodeling. Deposition of calcification in valves and arteries diminishes the valvular or arterial wall elasticity, a major cause of aneurysm and stenosis. Obstruction of arteries by calcification and other components can lead to heart attack and stroke. Mineralization in the femoral arteries can cause intermittent claudication in the legs, causing decreased mobility. Accurate measurement of calcification is essential for identifying other factors associated with this process and ultimately for elucidating the mechanism(s) of calcification. A wide range of methods for visualizing and measuring calcification for diagnosis and treatment in vivo and for studying the calcification process ex vivo are available. This review provides a critical comparison of older established methods and newer evolving technologies for quantifying calcification.

Tracking regression and progression of atherosclerosis in human carotid arteries using high-resolution magnetic resonance imaging

BACKGROUND AND PURPOSE

Magnetic resonance imaging (MRI) can accurately and reproducibly measure the volume of atherosclerotic plaque in human carotid arteries. Atherosclerotic plaques may either progress or regress over time, depending on individual risk factors and treatment regimens. This study was designed to determine if regression or progression of human carotid atherosclerosis in patients receiving statin therapy over 24 months can be detected by high-resolution MRI.

METHODS

In 11 subjects who had undergone unilateral carotid endarterectomy and were on statin therapy, volumes for total carotid artery, concentric wall (normal wall), eccentric wall (plaque), and lumen were quantified at 0, 16 and 24 months using a 1.5-T human imager equipped with 6-cm phased array coils.

RESULTS

The interobserver mean coefficient of variation (CV) was lowest for the lumen volume (3.1%) and highest for the plaque volume (9.8%). The interscan mean CV was lowest for the total artery volume (3.2%) and highest for the plaque volume (9.9%). As much as 26% regression and 35% progression were observed in individual subject's carotid artery eccentric wall (plaque) volumes over time. Mean eccentric wall volume increased 5% by 16 months and 8% by 24 months. Mean total wall volume increased slightly at both 16 and 24 months (+1.2% and +1.8%).

CONCLUSIONS

High-resolution MRI provides a noninvasive reproducible method of tracking changes in carotid atherosclerosis. This pilot study detected changes in individual subjects at both 16 and 24 months. MRI tracking of changes in atherosclerotic plaques should prove useful in assessing vascular disease risk and monitoring the efficacy of interventions designed to induce regression or retard progression.

Carotid Plaque Mast Cells Associate with Atherogenic Serum Lipids, High Grade Carotid Stenosis and Symptomatic Carotid Artery Disease

OBJECTIVE

Increased numbers of mast cells (MCs) are present in ruptured coronary plaques, suggesting to play a role in acute coronary syndromes. We evaluated the distribution densities of MCs, macrophages and T cells in carotid plaques and correlated these findings to stroke risk factors as well as history of stroke or TIA.

METHODS AND RESULTS

Seventy-eight carotid samples from 75 patients (16 plaques from asymptomatic patients and 62 from patients with recent ischemic symptoms) undergoing carotid endarterectomy with an internal carotid stenosis >70% that were immunostained and quantified for MCs, macrophages and T cells. The MC distribution density showed positive correlation with the degree of carotid stenosis (p = 0.012), serum levels of total cholesterol (p = 0.021), LDL cholesterol (p = 0.013) and triglycerides (p = 0.005), and an inverse correlation with serum HDL cholesterol levels (p = 0.001). The average MC density (p = 0.023), but not the macrophage (p = 0.58) or T cell (p = 0.74) density, was higher in the symptomatic than in the asymptomatic patients. In a comparison of plaques ipsilateral and contralateral to the thromboembolic event, the densities of the three types of inflammatory cells were similar.

CONCLUSIONS

Increased MC distribution density is associated with an atherogenic serum lipid profile, high-grade carotid artery stenosis and symptomatic carotid artery disease. These findings suggest a potential involvement of MCs in the pathophysiology of carotid artery stenosis.

Determination of carotid artery atherosclerotic lesion type and distribution in hypercholesterolemic patients with moderate carotid stenosis using noninvasive magnetic resonance imaging

BACKGROUND AND PURPOSE

The aims of this study were to noninvasively determine carotid atherosclerotic lesion type and distribution and to evaluate the reproducibility of determining lesion types in asymptomatic patients with moderate hypercholesterolemia and moderate carotid artery (CA) stenosis using MRI.

METHODS

Forty-two asymptomatic patients with moderate CA stenosis underwent bilateral carotid MRI in a 1.5-T scanner using a protocol that generated 4 contrast weightings (T1, T2, proton density, and 3D time of flight). MRI-modified American Heart Association criteria were used to evaluate lesion types at 3 locations (common and internal CA [CCA and ICA, respectively] and CA bifurcation) and at the minimum lumen area. Two identical MR scans were conducted to evaluate reproducibility of lesion types.

RESULTS

Lesion types were obtained from 230 locations. Type III (39%) occurred most commonly, followed by types IV-V (25%), I-II (20%), VI (12%), and VII (4%). Type III was more commonly distributed in the CCA (n=35, 39%) and ICA (n=32, 36%). Type IV-V was more commonly distributed in the CCA (n=24, 41%) and at the bifurcation (n=21, 36%). Forty-two lesions were available at the site of minimum lumen area: type III (33%), IV-V (33%), VI (29%), and VII (5%). There was good agreement of lesion types between both MRI scans (Cohen's kappa=0.73; 95% CI: 0.65 to 0.81).

CONCLUSIONS

MRI can determine lesion types reproducibly as well as the distribution of lesions in hypercholesterolemic patients with moderate CA stenosis. A wide range of lesion types, including advanced lesions, were found in these patients.