Carotid plaque imaging and the risk of atherosclerotic cardiovascular disease

Remnant cholesterol and the risk of carotid plaque in hypertension: results from a community-based screening among old adults in Hangzhou, China

Elevated remnant cholesterol (RC) is considered a risk factor for atherosclerotic cardiovascular disease, but the evidence on this association applies to the Chinese population with hypertension is limited. We aimed to explore the association between RC levels and carotid plaque in old adults with hypertension. 8523 hypertensive patients aged ≥ 60 years with serum lipids and carotid ultrasonography data were included in this community-based screening. Fasting RC was calculated as total cholesterol minus high-density lipoprotein cholesterol minus low-density lipoprotein cholesterol (LDLC). The associations of RC levels with carotid plaque risk were evaluated using Logistic regression and restricted cubic spline models. Carotid plaque was screened in 4821 (56.56%) subjects. After multivariable-adjusted, RC was significantly related to carotid plaque [Odd ratio (OR)] = 1.043 per 0.1 mmol/L increase, 95% confidence interval (CI): 1.030-1.056). The highest versus the lowest quartile of RC was 1.928 (1.673-2.223) for carotid plaque. A nonlinear association was found between serum RC levels and the risk of carotid plaque (P for nonlinearity < 0.001). Moreover, an RC > 0.78 mmol/L differentiated patients at a higher risk of carotid plaque compared to those at lower concentrations, regardless of whether LDLC was on target at 2.59 mmol/L. In old adults with hypertension, elevated RC was positively associated with carotid plaque, independent of LDLC and other conventional risk factors.

In vitro analysis of carotid lesions using a preliminary microwave sensor to detect vulnerable plaques: Correlation with histology, Duplex ultrasound examination, and computed tomography scanner: The Imaging and Microwave Phenotyping Assessment of Carotid stenosis Threat (IMPACT) study

Objective

Progress in best medical treatment have made identification of best candidates for carotid surgery more difficult. New diagnostic modalities could be helpful in this perspective. Microwaves (MWs) can quantify dielectric properties (complex relative permittivity) of biological tissues and MW technology has emerged as a promising field of research for distinguishing abnormal tissues from healthy ones. We here evaluated the ability of a dedicated MW sensor developed in our laboratory to identify vulnerable carotid lesions.

Methods

We included 50 carotid lesions in this study. The plaques were analyzed and classified preoperatively by ultrasound (US) examination, computed tomography angiography and tested postoperatively using a MW sensor. Histopathological analysis was used as a gold standard to separate vulnerable plaques (VPs) from nonvulnerable plaques (NVPs).

Results

VPs were more frequently types 2 or 3 plaques (on US examination), had a greater proportion of low (<60 Hounsfield unit) and moderate (60-130 Hounsfield unit) attenuation components (computed tomography angiography) and displayed higher dielectric constant values (MW) than NVPs, which had an opposite profile. NVPs were more frequently asymptomatic plaques compared with VPs (P = .035). Multivariate analysis showed that US examination and MW identified VPs with a sensitivity of 77% and a specificity of 76% (cutoff value, -0.045; area under the curve, 0.848; P < .0001).

Conclusions

We found that the presence of types 2 to 3 (on US examination) and high dielectric constant plaques in vitro was highly indicative of a VP based on histological analysis. Further studies are needed to determine the potential of MW to identify the most dangerous asymptomatic carotid lesions.

Extracranial carotid artery atherosclerotic plaque and APOE polymorphisms: a systematic review and meta-analysis

Introduction

Carotid atherosclerotic plaque is an important independent risk factor for stroke. Apolipoprotein E (APOE) influences cholesterol levels and certain isoforms are associated with increased carotid atherosclerosis, though the exact association between APOE and carotid plaque is uncertain. The study aimed to evaluate the association between APOE and carotid plaque.

Methods

A systematic review was performed to retrieve all studies which examined the association between carotid plaque and APOE. This study was conducted in accordance with the PRISMA guidelines. Independent readers extracted the relevant data from each study including the type of imaging assessment, plaque definition, frequency of APOE E4 carrier status and type of genotyping. Meta-analyses with an assessment of study heterogeneity and publication bias were performed. Results were presented in a forest plot and summarized using a random-effects model.

Results

After screening 838 studies, 17 studies were included for systematic review. A meta-analysis of 5 published studies showed a significant association between ε4 homozygosity and carotid plaque [odds ratio (OR), 1.53; 95% CI, 1.16, 2.02; p = .003]. Additionally, there was a significant association between patients possessing at least one ε4 allele, heterozygotes or homozygotes, and carotid plaque (OR, 1.25; 95% CI, 1.03, 1.52; p = .03). Lastly, there was no association between ε4 heterozygosity and carotid plaque (OR, 1.08; 95% CI, 0.93, 1.26; p = .30).

Conclusion

APOE ε4 allele is significantly associated with extracranial carotid atherosclerotic plaque, especially for homozygous individuals.

Identification of vulnerable carotid plaque with CT-based radiomics nomogram

AIM

To develop and validate a radiomics nomogram for identifying high-risk carotid plaques on computed tomography (CT) angiography (CTA).

MATERIALS AND METHODS

A total of 280 patients with symptomatic (n=131) and asymptomatic (n=139) carotid plaques were divided into a training set (n=135), validation set (n=58), and external test set (n=87). Radiomic features were extracted from CTA images. A radiomics model was constructed based on selected features and a radiomics score (rad-score) was calculated. A clinical factor model was constructed by demographics and CT findings. A radiomics nomogram combining independent clinical factors and the rad-score was constructed. The diagnostic performance of three models was evaluated and validated by region of characteristic curves.

RESULTS

Calcification and maximum plaque thickness were the independent clinical factors. Twenty-four features were used to build the radiomics signature. In the validation set, the nomogram (area under the curve [AUC], 0.977; 95% CI, 0.899-0.999) performed better (p=0.017 and p=0.031) than the clinical factor model (AUC, 0.862; 95% CI, 0.746-0.938) and radiomics signature (AUC, 0.944; 95% CI, 0.850-0.987). In external test set, the nomogram (AUC, 0.952; 95% CI, 0.884-0.987) and radiomics signature (AUC, 0.932; 95% CI, 0.857-0.975) showed better discrimination capability (p=0.002 and p=0.037) than clinical factor model (AUC, 0.818; 95% CI, 0.721-0.892).

CONCLUSION

The CT-based nomogram showed satisfactory performance in identification of high-risk plaques in carotid arteries, and it may serve as a potential non-invasive tool to identify carotid plaque vulnerability and risk stratification.

Combined near infrared photoacoustic imaging and ultrasound detects vulnerable atherosclerotic plaque

Atherosclerosis is an inflammatory process resulting in the deposition of cholesterol and cellular debris, narrowing of the vessel lumen and clot formation. Characterization of the morphology and vulnerability of the lesion is essential for effective clinical management. Here, near-infrared auto-photoacoustic (NIRAPA) imaging is shown to detect plaque components and, when combined with ultrasound imaging, to differentiate stable and vulnerable plaque. In an ex vivo study of photoacoustic imaging of excised plaque from 25 patients, 88.2% sensitivity and 71.4% specificity were achieved using a clinically-relevant protocol. In order to determine the origin of the NIRAPA signal, immunohistochemistry, spatial transcriptomics and spatial proteomics were co-registered with imaging and applied to adjacent plaque sections. The highest NIRAPA signal was spatially correlated with bilirubin and associated blood-based residue and with the cytoplasmic contents of inflammatory macrophages bearing CD74, HLA-DR, CD14 and CD163 markers. In summary, we establish the potential to apply the NIRAPA-ultrasound imaging combination to detect vulnerable carotid plaque and a methodology for fusing molecular imaging with spatial transcriptomic and proteomic methods.

Contrast-Enhanced Ultrasound Feasibility in Assessing Carotid Plaque Vulnerability-Narrative Review

The risk assessment for carotid atherosclerotic lesions involves not only determining the degree of stenosis but also plaque morphology and its composition. Recently, carotid contrast-enhanced ultrasound (CEUS) has gained importance for evaluating vulnerable plaques. This review explores CEUS's utility in detecting carotid plaque surface irregularities and ulcerations as well as intraplaque neovascularization and its alignment with histology. Initial indications suggest that CEUS might have the potential to anticipate cerebrovascular incidents. Nevertheless, there is a need for extensive, multicenter prospective studies that explore the relationships between CEUS observations and patient clinical outcomes in cases of carotid atherosclerotic disease.

B-mode ultrasound characteristics of carotid plaques in symptomatic and asymptomatic patients with low-grade stenosis

Carotid plaque features assessed using B-mode ultrasound can be useful for the prediction of cerebrovascular symptoms. Therefore, the aim of this retrospective study was to determine the ability of ultrasound B-mode imaging to differentiate between carotid plaques causing less than 50% stenosis in symptomatic and asymptomatic patients. A dataset of 1,593 patients with carotid disease who underwent carotid ultrasound between 2016 and 2021 was evaluated retrospectively between January and April of 2022. A total of 107 carotid plaques from 35 symptomatic and 52 asymptomatic patients causing low-grade stenosis on B-mode images were included in the analysis. Chi-square, independent t-test and Mann-Whitney U test were used to compare the variables. There was a significant association between hypertension and the presence of cerebrovascular symptoms (p = 0.01). Predominantly hypoechoic and hyperechoic carotid plaque were significantly associated with the presence and absence of cerebrovascular symptoms, respectively (predominantly hypoechoic: p = 0.01; predominantly hyperechoic: p = 0.02). Surface irregularity was significantly associated with the presence of cerebrovascular symptoms (p = 0.02). There is was a significant difference in the carotid plaque length and area between the symptomatic and asymptomatic patients (plaque length: symptomatic median 9 mm, interquartile range [IQR] 6 mm; asymptomatic median 6 mm, IQR 4.5 mm, p = 0.01; plaque area: symptomatic median 24 mm, IQR 30 mm; asymptomatic median 14 mm, IQR 17 mm, p = 0.01); however, this difference was not significant for plaque thickness (p = 0.55), or common carotid artery intima-media thickness (p = 0.7). Our findings indicate that hypertension patients with predominantly hypoechoic carotid plaques and plaques with an irregular surface are associated with the presence of cerebrovascular symptoms. In addition, the carotid plaques in symptomatic patients were longer and larger compared to asymptomatic patients.

The association of stroke risk factors with the future thickness of carotid atherosclerotic plaques

OBJECTIVES

An advancing atherosclerotic plaque is a risk factor for stroke. We conducted this study to assess the relationship between risk factors of stroke with changing in the thickness of carotid plaques thickness evident on sonography.

METHODS

We carried out a secondary analysis of data from a study on carotid bifurcation plaques. Data were collected in the sonography laboratories of two university hospitals. In total, 564 (240; 42.6% men) patients with atherosclerotic plaques in the carotid bifurcation and internal carotid artery with stenosis ≥ 30% evident on duplex sonography were included. We developed machine learning models using an extreme gradient boosting algorithm with Shapley additive explanation method to find important risk factors and their interactions. The outcome was a change in the carotid plaque thickness after 36 months, and the predictors were initial plaque thickness and the risk factors of stroke.

RESULTS

Two regression models were developed for left and right carotid arteries. The R-squared values were 0.964 for the left, and 0.993 for the right model. Overall, the three top features were BMI, age, and initial plaque thickness for both left and right plaques. However, the risk factors of stroke showed stronger interaction in predicting plaque thickening of the left carotid more than the right carotid artery.

DISCUSSION

The effect of each predictor on plaque thickness is complicated by interactions with other risk factors, particularly for the left carotid artery. The side of carotid artery involvement should be considered for stroke prevention.

Impact of HBV infection on clinical outcomes in patients with metabolic dysfunction-associated fatty liver disease

Background & Aims

The new name and diagnostic criteria of metabolic-associated fatty liver disease (MAFLD) was proposed in 2020. Although chronic HBV infection has protective effects on lipid profiles and hepatic steatosis, the impact of chronic HBV infection on clinical outcomes of MAFLD requires further investigation.

Methods

The participants from a Taiwan bio-bank cohort were included. MAFLD is defined as the presence of hepatic steatosis plus any of the following three conditions: overweight/obesity, type 2 diabetes mellitus, and metabolic dysfunction. The patients with positive glycated haemoglobin were considered as having chronic HBV infection. Atherosclerosis was determined as having carotid plaques on duplex ultrasound. Advanced liver fibrosis was defined as Fibrosis-4 >2.67. Based on the status of MAFLD and HBV infection, the participants were distributed into four groups: 'dual aetiology', 'MAFLD alone', 'HBV alone', and 'healthy controls'.

Results

A total of 20,460 participants (age 55.51 ± 10.37; males 32.67%) were included for final analysis. The prevalence of MAFLD and chronic HBV infections were 38.8% and 10.3%, respectively. According to univariate analysis, 'HBV alone' group had lower levels of glycated haemoglobin, lipid profiles, and intima media thickness than healthy controls. The 'dual aetiology' group had lower levels of triglycerides, cholesterol, γ-glutamyl transferase, intima media thickness, and percentage of carotid plaques than 'MAFLD alone' group. Using binary logistic regression, chronic HBV infection increased the overall risk of advanced liver fibrosis; and had a lower probability of carotid plaques in MAFLD patients, but not in those without MAFLD.

Conclusions

The large population-based study revealed chronic HBV infection increases the overall risk of liver fibrosis, but protects from atherosclerosis in patients with MAFLD.

Impact and implications

Patients with metabolic-associated fatty liver disease can also be coinfected with chronic HBV. Concomitant HBV infection increases the overall risk of liver fibrosis, but protects from atherosclerosis in patients with MAFLD.

Combined near infrared photoacoustic imaging and ultrasound detects vulnerable atherosclerotic plaque

Atherosclerosis is an inflammatory process resulting in the deposition of cholesterol and cellular debris, narrowing of the vessel lumen and clot formation. Characterization of the morphology and vulnerability of the lesion is essential for effective clinical management. Photoacoustic imaging has sufficient penetration and sensitivity to map and characterize human atherosclerotic plaque. Here, near infrared photoacoustic imaging is shown to detect plaque components and, when combined with ultrasound imaging, to differentiate stable and vulnerable plaque. In an ex vivo study of photoacoustic imaging of excised plaque from 25 patients, 88.2% sensitivity and 71.4% specificity were achieved using a clinically-relevant protocol. In order to determine the origin of the near-infrared auto-photoacoustic (NIRAPA) signal, immunohistochemistry, spatial transcriptomics and proteomics were applied to adjacent sections of the plaque. The highest NIRAPA signal was spatially correlated with bilirubin and associated blood-based residue and inflammatory macrophages bearing CD74, HLA-DR, CD14 and CD163 markers. In summary, we establish the potential to apply the NIRAPA-ultrasound imaging combination to detect vulnerable carotid plaque.

Association between the atherogenic index of plasma and carotid artery plaques in patients with coronary heart disease in different glucose metabolism states: an RCSCD-TCM study in Tianjin, China

BACKGROUND

The atherogenic index of plasma (AIP) is considered a powerful biomarker of dyslipidemia and atherosclerosis (AS). However, limited evidence is available regarding the relationship between the AIP and carotid artery plaques (CAPs) in patients with coronary heart disease (CHD).

METHODS

This retrospective study included 9281 patients with CHD who underwent carotid ultrasound. Participants were divided according to the AIP tertiles: T1, AIP < 1.02; T2, 1.02 ≤ AIP < 1.25; and T3, AIP ≥ 1.25. The presence or absence of CAPs was assessed using carotid ultrasound. Logistic regression was used to analyze the relationship between the AIP and CAPs in patients with CHD. The relationship between the AIP and CAPs was assessed according to sex, age, and glucose metabolic status.

RESULTS

The baseline characteristics revealed significant differences in related parameters among patients with CHD after stratification into the three groups according to the AIP tertiles. Compared with T1, the odds ratio (OR) of T3 in patients with CHD was 1.53 (95% confidence interval [CI]:1.35-1.74). The association between AIP and CAPs was higher in females (OR: 1.63; 95% CI: 1.38-1.92) than in males (OR: 1.38; 95% CI: 1.12-1.70). The OR for patients aged ≤60 years (OR: 1.40; 95% CI: 1.14-1.71) was lower than that for patients aged >60 years (OR: 1.49; 95% CI: 1.26-1.76). AIP was significantly associated with the risk of CAPs formation in different glucose metabolic states, with diabetes having the highest OR value (OR: 1.31; 95% CI: 1.19-1.43).

CONCLUSION

The AIP and CAPs were significantly associated in patients with CHD, and the association was higher in female than in male patients. The association was lower in patients aged ≤60 years than in patients aged >60 years. Under different glucose metabolism statuses, the association between the AIP and the CAPs among patients with CHD was highest in patients with diabetes.

Pearls and Pitfalls of Carotid Artery Imaging: Ultrasound, Computed Tomography Angiography, and MR Imaging

Stroke represents a major cause of morbidity and mortality worldwide with carotid atherosclerosis responsible for a large proportion of ischemic strokes. Given the high burden of the disease , early diagnosis and optimal secondary prevention are essential elements in clinical practice. For a long time, the degree of stenosis had been considered the parameter to judge the severity of carotid atherosclerosis. Over the last 30 years, literature has shifted attention from stenosis to structural characteristics of atherosclerotic lesion, eventually leading to the "vulnerable plaque" model. These "vulnerable plaques" frequently demonstrate high-risk imaging features that can be assessed by various non-invasive imaging modalities.

Reduced dose direct oral anticoagulants compared with warfarin with high time in therapeutic range in nonvalvular atrial fibrillation

Direct oral anticoagulants (DOACs) used in nonvalvular atrial fibrillation (NVAF) are dose-reduced in elderly and patients with impaired renal function. Only reduced dose dabigatran is concluded as having similar stroke risk reduction and lower risk of major bleeding than warfarin in the pivotal studies. In clinical practice, reduced dose is prescribed more often than expected making this an important issue. The objective of this study was to compare effectiveness and safety between reduced dose DOACs and high TTR warfarin treatment (TTR ≥ 70%) in NVAF. A Swedish anticoagulation registry was used in identifying eligible patients from July 2011 to December 2017. The study cohort consisted of 40,564 patients with newly initiated DOAC (apixaban, dabigatran, or rivaroxaban) (11,083 patients) or warfarin treatment (29,481 patients) after exclusion of 374,135 patients due to not being warfarin or DOAC naïve, not being prescribed reduced dose, having previous mechanical heart valve (MHV), or being under 18 years old. The median durations of follow up were 365, 419, 432 and 473 days for apixaban, dabigatran, rivaroxaban and warfarin, respectively. Warfarin TTR identified from Auricula was 70.0%. Endpoints (stroke and major bleeding) and baseline characteristics were collected from hospital administrative registers using ICD-10 codes. Cohorts were compared using weighted adjusted Cox regression after full optimal matching based on propensity scores. DOACs are associated with lower risk of major bleeding (HR with 95% CI) 0.85 (0.78-0.93), intracranial bleeding HR 0.64 (0.51-0.80), hemorrhagic stroke HR 0.68 (0.50-0.92), gastrointestinal bleeding HR 0.81 (0.69-0.96) and all-cause stroke HR 0.87 (0.76-0.99), than warfarin. Apixaban and dabigatran are associated with lower risk of major bleeding, HR 0.70 (0.63-0.78) and HR 0.80 (0.69-0.94), and rivaroxaban is associated with lower risk of ischemic stroke, HR 0.73 (0.59-0.96), with higher major bleeding risk, HR 1.31 (1.15-1.48), compared to warfarin. Apixaban is associated with higher all-cause mortality compared to warfarin, HR 1.12 (1.03-1.21). DOACs are associated with lower risk of major bleeding and all-cause stroke, than high quality warfarin treatment, with exception of rivaroxaban that carried higher risk of major bleeding and lower risk of stroke or systemic embolism. In this large observational registry-based NVAF cohort, DOACs are preferred treatment in patients with indication for DOAC dose reduction, even in a high TTR setting.

Measures of carotid atherosclerosis and fall-related hospitalization risk: The Perth Longitudinal Study of Ageing Women

BACKGROUND AND AIMS

We and others have identified links between cardiovascular conditions and poor musculoskeletal health. However, the relationship between measures of carotid atherosclerosis such as focal carotid plaque and common carotid intima media thickness (CCA-IMT) and falls remains understudied. This study examined the association between measures of carotid atherosclerosis and fall-related hospitalization over 11.5 years in community dwelling older women.

METHODS AND RESULTS

1116 older women recruited in 1998 to a five-year randomized controlled trial to examine the effect of calcium supplementation in preventing fracture and who had undertaken B-mode ultrasound in 2001 (three years after the baseline clinical visit) were included in this study. The participants were followed for over 11.5 years as Perth Longitudinal Study of Ageing Women (PLSAW). Over the follow up period, 428 (38.4%) women experienced a fall-related hospitalization. Older women with carotid plaque had 44% a higher relative hazard for fall-related hospitalization (HR 1.44; 95%CI, 1.18 to 1.76) compared to those without carotid plaque. The association persisted after adjustment for established falls risk factors such as measures of muscle strength and physical function.Each SD increase in the mean and maximum CCA-IMT was also associated with a higher risk of fall-related hospitalizations (HR 1.10; 95%CI, 1.00 to 1.21 and HR 1.11; 95%CI, 1.01 to 1.22, respectively).

CONCLUSIONS

Measures of carotid atherosclerosis are associated with a higher risk of fall-related hospitalization independent of established falls risk factors. These findings suggest the importance of vascular health when considering falls risk.

Neutrophil-lymphocyte ratio and carotid plaque burden in patients with essential thrombocythemia and polycythemia vera

BACKGROUND AND AIMS

Chronic inflammation plays a critical role in the pathogenesis of myeloproliferative neoplasm (MPN), and inflammatory conditions are closely related to the development and exacerbation of atherosclerosis. This study aimed to compare carotid plaque burden and neutrophil-lymphocyte ratio (NLR) in the essential thrombocythemia (ET)/polycythemia vera (PV) and control groups.

METHODS AND RESULTS

We retrospectively assessed carotid plaque burden and NLR in patients with ET/PV between January 2010 and September 2021 and propensity-score matched these patients to control subjects from the general population. All patients underwent carotid imaging using carotid ultrasonography for atherosclerosis screening. After 3:1 propensity-score matching, 140 patients in the control group were matched to 51 patients in ET/PV group. The mean NLR was significantly higher in the MPN group than in the control group (4.77 ± 3.96 vs. 1.93 ± 1.03, p < 0.001). The carotid plaque score was also higher in MPN group than in the control group (2.37 ± 1.47 vs. 1.94 ± 1.17, p = 0.038).

CONCLUSION

Patients with PV/ET show a higher NLR and carotid plaque burden than the normal population. This reflected that PV/ET was a highly inflammatory and atherosclerotic condition expressing potentially increased cardiovascular risk.

Contrast-enhanced ultrasound for the evaluation of symptomatic and asymptomatic carotid plaques: A systematic review and meta-analysis

BACKGROUND

Contrast-enhanced ultrasound (CEUS) is a promising imaging modality for the assessment of plaque vulnerability. We aimed to systematically review and meta-analyze the ability of CEUS parameters to differentiate between symptomatic and asymptomatic carotid plaques and to assess its reproducibility.

METHODS

PubMed, EMBASE, and Cochrane Library databases were searched for studies that potentially evaluated carotid plaques using CEUS. From the initial 2870 searches, 11 relevant publications comprising a total of 821 carotid plaques were reviewed. Data on CEUS parameters including quantitative and semi-quantitative parameters were extracted and analyzed.

RESULTS

The overall analysis showed significantly higher CEUS parameters in symptomatic carotid plaques compared to asymptomatic carotid plaques (standardised mean difference (SMD) .95, 95% confidence interval (CI) .56-1.27, p < .01). Intra and inter-observer reproducibility of quantitative CEUS parameters were excellent (intra-observer, r = .95, 95% CI .87-1; inter-observer, r = .93, 95% CI .80-.1). Semi-quantitative CEUS parameters showed good intra-observer reliability and moderate inter-observer reliability (intra-observer, r = .77, 95% CI .64-.89; inter-observer, r = .75, 95% CI .61-.89). Heterogeneity among studies compared CEUS parameters in symptomatic and asymptomatic plaques and studies assessed inter-observer reproducibility, and significant biases in studies assessing CEUS reproducibility were present.

CONCLUSION

CEUS is a useful vascular imaging method to differentiate between symptomatic and asymptomatic carotid plaques with moderate to excellent reproducibility. Quantitative CEUS analysis appeared to be more sensitive and reliable in assessing carotid plaques than semi-quantitative parameters. Further longitudinal prospective trials evaluating carotid plaque in asymptomatic population using CEUS to determine plaque characteristics that can become symptomatic are required.

Identification of Biomarkers of Autophagy-Related Genes Between Early and Advanced Carotid Atherosclerosis

Background

Accumulating evidence demonstrates that autophagy is important in inhibiting inflammation and cholesterol efflux. It suggested the autophagy may be a treatment of atherosclerosis. Thus, we screened autophagy-related mRNA to explore their mechanism of scientific basis for early diagnosis and therapy of atherosclerosis.

Methods

The GSE28829 datasets were assessed to analyze differentially expressed genes by GEO2R. And autophagy-related hub genes were identified by HADb. The biological function of autophagy-related DEmRNAs was examined by Metascape. The construction of a protein–protein network was explored by String. Cytohubba was utilized to screen hub genes. Analysis of DEmiRNA-mRNA pairs was executed by DIANA microT-CDS database. Finally, correlation analysis was carried out to identify the relationship between DEARGs and clinical and prognostic factors.

Results

A number of 1087 DEGs and 19 autophagy-related DEmRNAs were identified in advanced carotid atherosclerotic plaque compared with the early. The biological function containing development and growth was enriched. Moreover, we screened the top hub nodes with the highest degrees. MicroRNAs (miRNAs) are confirmed to participate in genesis and progression of atherosclerosis, so we further analyzed the miRNA–mRNA regulatory network genes with four hub genes to explore their potential mechanism in atherosclerosis. Then, we revealed co-expression of four key genes CTSB, ITGB1, CXCR4, TNFSF10 and autophagy-related genes. As for the clinical factors, hypertension factor showed higher expression of ITGB1. The probability of coronary heart disease factor was significantly increased with high expression of CTSB and CXCR4, as well as low expression of ITGB1 and TNFSF10. Diabetes factor tended to express distinguished levels of CTSB and ITGB1. TNFSF10 was highly expressed in both hyperlipidemia and ischemic stroke factor.

Conclusion

CTSB, ITGB1, CXCR4 and TNFSF10 may be critical in atherosclerosis development and were thought to be potential diagnostic biomarkers for atherosclerosis.

Targeting Peptide, Fluorescent Reagent Modified Magnetic Liposomes Coated with Rapamycin Target Early Atherosclerotic Plaque and Therapy

Atherosclerosis is the leading cause of global morbidity and mortality. Its therapy requires research in several areas, such as diagnosis of early arteriosclerosis, improvement of the pharmacokinetics and bioavailability of rapamycin as its therapeutic agents. Here, we used the targeting peptide VHPKQHR (VHP) (or fluorescent reagent) to modify the phospholipid molecules to target vascular cell adhesion molecule-1 (VCAM-1) and loaded ultrasmall paramagnetic iron oxide (USPIO/Fe₃O₄) plus rapamycin (Rap) to Rap/Fe₃O₄@VHP-Lipo (VHPKQHR-modified magnetic liposomes coated with Rap). This nanoparticle can be used for both the diagnosis and therapy of early atherosclerosis. We designed both an ex vivo system with mouse aortic endothelial cells (MAECs) and an in vivo system with ApoE knockout mice to test the labeling and delivering potential of Rap/Fe₃O₄@VHP-Lipo with fluorescent microscopy, flow cytometry and MRI. Our results of MRI imaging and fluorescence imaging showed that the T2 relaxation time of the Rap/Fe₃O₄@VHP-Lipo group was reduced by 2.7 times and 1.5 times, and the fluorescence intensity increased by 3.4 times and 2.5 times, respectively, compared with the normal saline group and the control liposome treatment group. It showed that Rap/Fe₃O₄@VHP-Lipo realized the diagnosis of early AS. Additionally, our results showed that, compared with the normal saline and control liposomes treatment group, the aortic fluorescence intensity of the Rap/Fe₃O₄@VHP-Lipo treatment group was significantly weaker, and the T2 relaxation time was prolonged by 8.9 times and 2.0 times, indicating that the targeted diagnostic agent detected the least plaques in the Rap/Fe₃O₄@VHP-Lipo treatment group. Based on our results, the synthesized theragnostic Rap/Fe₃O₄@VHP-Lipo serves as a great label for both MRI and fluorescence bimodal imaging of atherosclerosis. It also has therapeutic effects for the early treatment of atherosclerosis, and it has great potential for early diagnosis and can achieve the same level of therapy with a lower dose of Rap.

Contribution of UltraFast™ Ultrasound and Shear Wave Elastography in the Imaging of Carotid Artery Disease

Carotid artery disease is one of the main global causes of disability and premature mortality in the spectrum of cardiovascular diseases. One of its main consequences, stroke, is the second biggest global contributor to disability and burden via Disability Adjusted Life Years after ischemic heart disease. In the last decades, B-mode and Doppler-based ultrasound imaging techniques have become an indispensable part of modern medical imaging of carotid artery disease. However, they have limited abilities in carotid artery plaque and wall characterization and are unable to provide simultaneous quantitative and qualitative flow information while the images are burdened by low framerates. UltraFast™ ultrasound is able to overcome these obstacles by providing simultaneous quantitative and qualitative flow analysis information in high frame rates via UltraFast™ Doppler. Another newly developed ultrasound technique, shear wave elastography, is based on the visualization of induced shear waves and the measurement of the shear wave propagation speed in the examined tissues which enables real-time carotid plaque and wall analysis. These newly developed ultrasound modalities have potential to significantly improve workflow efficiency and are able to provide a plethora of additional imaging information of carotid artery disease in comparison to conventional ultrasound techniques.

Risk factors for carotid plaque progression after optimising the risk factor treatment: substudy results of the Atherosclerotic Plaque Characteristics Associated with a Progression Rate of the Plaque and a Risk of Stroke in Patients with the carotid Bifurcation Plaque Study (ANTIQUE)

BACKGROUND AND AIM

Carotid plaque progression contributes to increasing stroke risk. The study aims to identify factors influencing carotid plaque thickness progression after changing the preventive treatment to the 'treating arteries instead of risk factors' strategy, that is, change in treatment depending on the progression of atherosclerosis.

METHODS

The study participants who completed sonographic controls over the course of 3 years were enrolled to the analysis. Duplex sonography of cervical arteries was performed in 6-month intervals with measurement of carotid plaque thickness. Plaque thickness measurement error (σ) was set as 3 SD. Only evidently stable and progressive plaques (defined as plaque thickness difference between initial and final measurements of ˂σ and >2σ, respectively) were included to analysis. Univariate and multivariate logistic regression analysis was performed to identify factors influencing plaque progression.

RESULTS

A total of 1391 patients (466 males, age 67.2±9.2 years) were enrolled in the study. Progressive plaque in at least one carotid artery was detected in 255 (18.3%) patients. Older age, male sex, greater plaque thickness, coronary heart disease, vascular surgery/stenting history and smoking were more frequently present in patients with progressive plaque (p˂0.05 in all cases). Multivariate logistic regression analysis identified only the plaque thickness (OR 1.850 for left side, 95% CI 1.398 to 2.449; and OR 1.376 for right side, 95% CI 1.070 to 1.770) as an independent factor influencing plaque progression.

CONCLUSION

Carotid plaque thickness corresponding to stenosis severity is the only independent risk factor for plaque thickness progression after optimising the prevention treatment.

TRIAL REGISTRATION NUMBER

NCT02360137.

Carotid Intraplaque Neovascularization and Future Vascular Events in Patients With Asymptomatic Carotid Stenosis

Objective: Intraplaque neovascularization is a marker of plaque vulnerability and is used to predict the risk of future vascular events in patients with symptomatic carotid stenosis; however, its association with asymptomatic carotid stenosis has not been prospectively evaluated. Therefore, this study aimed to explore the association between intraplaque neovascularization assessed using contrast-enhanced ultrasound and the occurrence of future ischemic events in asymptomatic patients diagnosed with carotid stenosis.

Methods: We recruited patients with asymptomatic carotid stenosis from our center. Contrast-enhanced ultrasound was performed at baseline. The outcomes were ischemic stroke and cardiovascular events. We plotted Kaplan-Meier survival curves and performed a log-rank test to compare endpoint event probability in patients with and without grade 2 intraplaque neovascularization. Univariate and multivariate Cox proportional hazards models were used to assess predictors of future vascular events.

Results: The data of 50 participants were included in the analysis (median follow-up, 43.7 months). Endpoint events occurred in 12 participants (24%). The Kaplan-Meier survival curves showed that patients with grade 2 intraplaque neovascularization had a higher probability of future vascular events than those with grades 0 and 1 (p < .05). Grade 2 intraplaque neovascularization (hazard ratio: 4.530, 95% confidence interval, 1.337–15.343, p < .05) was an independent predictor of future vascular events in patients with asymptomatic carotid stenosis.

Conclusion: Grade 2 intraplaque neovascularization assessed using contrast-enhanced ultrasound independently predicted future ischemic events in patients with asymptomatic carotid stenosis, and contrast-enhanced ultrasound may be an effective screening method to identify high-risk subgroups of patients with asymptomatic carotid stenosis.

Imaging High-Risk Atherothrombosis Using a Novel Fibrin-Binding Positron Emission Tomography Probe

BACKGROUND AND PURPOSE

High-risk atherosclerosis is an underlying cause of cardiovascular events, yet identifying the specific patient population at immediate risk is still challenging. Here, we used a rabbit model of atherosclerotic plaque rupture and human carotid endarterectomy specimens to describe the potential of molecular fibrin imaging as a tool to identify thrombotic plaques.

METHODS

Atherosclerotic plaques in rabbits were induced using a high-cholesterol diet and aortic balloon injury (N=13). Pharmacological triggering was used in a group of rabbits (n=9) to induce plaque disruption. Animals were grouped into thrombotic and nonthrombotic plaque groups based on gross pathology (gold standard). All animals were injected with a novel fibrin-specific probe ⁶⁸Ga-CM246 followed by positron emission tomography (PET)/magnetic resonance imaging 90 minutes later. ⁶⁸Ga-CM246 was quantified on the PET images using tissue-to-background (back muscle) ratios and standardized uptake value.

RESULTS

Both tissue-to-background (back muscle) ratios and standardized uptake value were significantly higher in the thrombotic versus nonthrombotic group (P<0.05). Ex vivo PET and autoradiography of the abdominal aorta correlated positively with in vivo PET measurements. Plaque disruption identified by ⁶⁸Ga-CM246 PET agreed with gross pathology assessment (85%). In ex vivo surgical specimens obtained from patients undergoing elective carotid endarterectomy (N=12), ⁶⁸Ga-CM246 showed significantly higher binding to carotid plaques compared to a D-cysteine nonbinding control probe.

CONCLUSIONS

We demonstrated that molecular fibrin PET imaging using ⁶⁸Ga-CM246 could be a useful tool to diagnose experimental and clinical atherothrombosis. Based on our initial results using human carotid plaque specimens, in vivo molecular imaging studies are warranted to test ⁶⁸Ga-CM246 PET as a tool to stratify risk in atherosclerotic patients.

Low-/high-density lipoprotein cholesterol ratio and carotid plaques in patients with coronary heart disease: a Chinese cohort study

Background

Evidence on the relationship between the low−/high-density lipoprotein cholesterol ratio (LDL-C/HDL-C) and carotid plaques remains limited. This study aimed to examine the association between LDL-C/HDL-C and carotid plaques in participants with coronary heart disease (CHD) and to further explore the extent to which a healthy lifestyle reduces the risk of LDL-C/HDL-C-related carotid plaques.

Methods

This large-scale and multi-centre retrospective study included 9426 CHD patients (aged 35–75 years) between January 1, 2014 and September 30, 2020. The LDL-C/HDL-C values were converted to the following tertiles: lowest (< 2.15), middle (2.15–3), and highest (> 3). Healthy lifestyle-related factors referred to whether or not the participant was a non-smoker and non-drinker. Participants were divided into an unfavourable group (those who did not adhere to healthy lifestyle factors), intermediate (only one unhealthy factor), and favourable (neither of the two unhealthy factors). Logistic regression was used for statistical analyses.

Results

Of the 9426 participants, 6989 (74.15%) CHD patients had carotid plaques. After adjustment for confounders, each unit increase in the LDL-C/HDL-C was significantly associated with carotid plaques (OR: 1.61; 95%CI: 1.43–1.84; P <  0.001). Multivariate logistic regression revealed that carotid plaques risk for the highest tertile (> 3) was 1.18 times that of the lowest quartile (< 2.15). Compared with an unfavourable lifestyle, an intermediate or a favourable lifestyle was associated with a significant 30% (OR: 0.70; 95%CI: 0.64–0.78; P <  0.001) or 67% (OR: 0.33; 95%CI: 0.29–0.37; P <  0.001) reduction in carotid plaques risk, respectively, among CHD patients with high LDL-C/HDL-C. There were significantly additive and multiplicative interactions between lifestyle and LDL-C/HDL-C with regards to carotid plaques.

Conclusion

A high LDL-C/HDL-C is associated with a risk of carotid plaques developing in CHD patients. Adhering to a healthy lifestyle has additive beneficial effects on reducing the risk of carotid plaques, especially in relation to the highest LDL-C/HDL-C.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12944-021-01575-w.

Apolipoprotein Signature of HDL and LDL from Atherosclerotic Patients in Relation with Carotid Plaque Typology: A Preliminary Report

In the past years, it has become increasingly clear that the protein cargo of the different lipoprotein classes is largely responsible for carrying out their various functions, also in relation to pathological conditions, including atherosclerosis. Accordingly, detailed information about their apolipoprotein composition and structure may contribute to the revelation of their role in atherogenesis and the understanding of the mechanisms that lead to atherosclerotic degeneration and toward vulnerable plaque formation. With this aim, shotgun proteomics was applied to identify the apolipoprotein signatures of both high-density and low-density lipoproteins (HDL and LDL) plasma fractions purified from healthy volunteers and atherosclerotic patients with different plaque typologies who underwent carotid endarterectomy. By this approach, two proteins with potential implications in inflammatory, immune, and hemostatic pathways, namely, integrin beta-2 (P05107) and secretoglobin family 3A member 2 (Q96PL1), have been confirmed to belong to the HDL proteome. Similarly, the list of LDL-associated proteins has been enriched with 21 proteins involved in complement and coagulation cascades and the acute-phase response, which potentially double the protein species of LDL cargo. Moreover, differential expression analysis has shown protein signatures specific for patients with “hard” or “soft” plaques.

Calcification patterns in femoral and carotid atheromatous plaques: A comparative morphometric study

This comparative study was designed to focus on the mineral patterns in human atherosclerotic plaques based on quantitative measurements of calcium deposits through the morphometric method. A total of 101 atherosclerotic plaques were harvested by conventional transluminal angioplasty from the carotid artery (CA) and different segments of the femoral-popliteal axis (FPA), fixed in formalin and sent for histological processing. The histological grade of the atherosclerotic plaque and the calcification pattern were evaluated, followed by a morphometric analysis of the mineral deposits. Regarding the localization, the advanced plaques (VII and VIII types) developed predominantly at the level of the superficial femoral artery (SFA) compared to the CA (P<0.001). This significant difference was maintained even if they were divided into low grade (IV and V) and high grade categories (VI, VII and VIII) (P<0.05). Compared with that in the carotid plaques, in the FPA plaques the mineralized surface increased in parallel with the narrowing of the vascular lumen diameter. The image analysis of the total pathological calcification score (pCS) showed a significant difference between the CA plaques and distal SFA (dSFA) plaques (P=0.038) and between the proximal SFA (pSFA) and dSFA plaques (P=0.013). In the case of the simple nodular pattern, calcification occupied significantly larger areas in the plaques developed in the dSFA and popliteal artery (PA) in comparison with the CA plaques (P=0.0007 and P=0.0009). pCSs calculated in plaques with extensive calcification pattern showed a lower value in the CA vs. the pSFA plaques (P=0.004). A less pronounced, but significant difference was observed between the pCS of pSFA and dSFA plaques (P=0.017). Femoral and carotid plaques exhibited different morphology and tendency for calcification. In parallel with the narrowing of the vascular lumen diameter, the mineralized surface increased at the level of different FPA segments. These results suggest that the mechanism is site-specific, and wall structure-dependent.

Detection of Carotid Artery Stenosis with Intraplaque Hemorrhage and Neovascularization Using a Scanning Interferometer

Carotid artery stenosis (CAS) is a major cause of stroke or transient ischemic attack (TIA, mini-stroke) in the United States. Carotid endarterectomy (CEA), a surgical procedure, is used to treat CAS. According to the American Heart Association, 1 out of 5 patients underwent CEA inappropriately, which was most commonly due to apparent overestimation of stenosis severity, and half had uncertain indicators. The current imaging modalities are limited in providing critical information on carotid arterial plaque content, extent, and biology. To circumvent these limitations, we developed a sensing interferometer (SI) imaging system to assess vulnerable carotid plaques noninvasively to detect stenosis, neovascularization, and intraplaque hemorrhage (IPH). We have custom-built a SI prototype and its peripheral systems with back-mode-projection capability. We detected stenosis, neo-vessels, and IPH through SI imaging system in in vivo mice carotid atherosclerotic plaques and further verified the same plaques ex vivo through a histology scope, CRi Maestro, and histological analysis.

Factors associated with atherosclerotic plaque echogenicity in patients aged 40-64 with carotid atherosclerosis

Aim    To identify clinical and laboratory indexes related with the atherosclerotic plaque (ASP) echogenicity based on results of the analysis of grey-scale median (GSM) in patients aged 40-64 years.Material and methods    The study included patients aged 40-64 years with carotid atherosclerosis. The carotid duplex scanning was performed for all patients. The GSM analysis of obtained images was performed with the Adobe Photoshop CS6 software.Results    Atherosclerotic cardiovascular diseases were found in 31 (21.4 %) patients. Correlation analysis determined inverse interrelationships between GSM and the body weight index (BWI) (r=-0.359; p&lt;0.0001), waist circumference (r=-0.357; p&lt;0.0001), and levels of uric acid (r=-0.244; p=0.021) and glucose (r=-0.205; p=0.032). According to the regression, statistically significant correlations remained between GSM and BWI as well as the waist circumference after the adjustment for sex and age.Conclusion    In patients with carotid atherosclerosis aged 40-64 years, the decrease in ASP GSM was associated with increases in BWI and waist circumference.

Multimodality carotid plaque tissue characterization and classification in the artificial intelligence paradigm: a narrative review for stroke application

Cardiovascular disease (CVD) is one of the leading causes of morbidity and mortality in the United States of America and globally. Carotid arterial plaque, a cause and also a marker of such CVD, can be detected by various non-invasive imaging modalities such as magnetic resonance imaging (MRI), computer tomography (CT), and ultrasound (US). Characterization and classification of carotid plaque-type in these imaging modalities, especially into symptomatic and asymptomatic plaque, helps in the planning of carotid endarterectomy or stenting. It can be challenging to characterize plaque components due to (I) partial volume effect in magnetic resonance imaging (MRI) or (II) varying Hausdorff values in plaque regions in CT, and (III) attenuation of echoes reflected by the plaque during US causing acoustic shadowing. Artificial intelligence (AI) methods have become an indispensable part of healthcare and their applications to the non-invasive imaging technologies such as MRI, CT, and the US. In this narrative review, three main types of AI models (machine learning, deep learning, and transfer learning) are analyzed when applied to MRI, CT, and the US. A link between carotid plaque characteristics and the risk of coronary artery disease is presented. With regard to characterization, we review tools and techniques that use AI models to distinguish carotid plaque types based on signal processing and feature strengths. We conclude that AI-based solutions offer an accurate and robust path for tissue characterization and classification for carotid artery plaque imaging in all three imaging modalities. Due to cost, user-friendliness, and clinical effectiveness, AI in the US has dominated the most.

Shear-Wave Elastography Enables Identification of Unstable Carotid Plaque

Shear-wave elastography (SWE) is a novel ultrasound technique for quantifying tissue elasticity. The aim of this study was to identify differences in atherosclerotic plaque elasticity measured using SWE among individuals with symptomatic, asymptomatic progressive and asymptomatic stable carotid plaques. Consecutive patients from the Atherosclerotic Plaque Characteristics Associated with a Progression Rate of the Plaque and a Risk of Stroke in Patients with the Carotid Bifurcation Plaque Study were screened for this research. Neurosonography examination of carotid arteries was performed to identify plaque stenosis of ≥50% using B-mode ultrasound and SWE imaging to measure the mean, maximal and minimal elasticity. The set consisted of 97 participants-74 with asymptomatic stable stenosis, 12 with asymptomatic progressive stenosis and 11 with symptomatic stenosis. The mean elasticity in the asymptomatic stable plaque group was significantly higher than in the asymptomatic progressive (52.2 vs. 30.4 kPa; p < 0.001) and symptomatic (52.2 vs. 36.4 kPa; p = 0.033) plaque groups. No significant differences were found between asymptomatic progressive and symptomatic (p > 0.1) plaque groups. Asymptomatic stable, asymptomatic progressive and symptomatic plaques did not differ in echogenicity, calcifications, homogeneity, occurrence of ulcerated surface, or intra-plaque hemorrhage (p > 0.05 in all cases). SWE was a helpful modality for differentiating between stable and unstable atherosclerotic plaques in carotid arteries.

Ten things to know about ten imaging studies: A preventive cardiology perspective ("ASPC top ten imaging")

Knowing the patient's current cardiovascular disease (CVD) status, as well as the patient's current and future CVD risk, helps the clinician make more informed patient-centered management recommendations towards the goal of preventing future CVD events. Imaging tests that can assist the clinician with the diagnosis and prognosis of CVD include imaging studies of the heart and vascular system, as well as imaging studies of other body organs applicable to CVD risk. The American Society for Preventive Cardiology (ASPC) has published "Ten Things to Know About Ten Cardiovascular Disease Risk Factors." Similarly, this "ASPC Top Ten Imaging" summarizes ten things to know about ten imaging studies related to assessing CVD and CVD risk, listed in tabular form. The ten imaging studies herein include: (1) coronary artery calcium imaging (CAC), (2) coronary computed tomography angiography (CCTA), (3) cardiac ultrasound (echocardiography), (4) nuclear myocardial perfusion imaging (MPI), (5) cardiac magnetic resonance (CMR), (6) cardiac catheterization [with or without intravascular ultrasound (IVUS) or coronary optical coherence tomography (OCT)], (7) dual x-ray absorptiometry (DXA) body composition, (8) hepatic imaging [ultrasound of liver, vibration-controlled transient elastography (VCTE), CT, MRI proton density fat fraction (PDFF), magnetic resonance spectroscopy (MRS)], (9) peripheral artery / endothelial function imaging (e.g., carotid ultrasound, peripheral doppler imaging, ultrasound flow-mediated dilation, other tests of endothelial function and peripheral vascular imaging) and (10) images of other body organs applicable to preventive cardiology (brain, kidney, ovary). Many cardiologists perform cardiovascular-related imaging. Many non-cardiologists perform applicable non-cardiovascular imaging. Cardiologists and non-cardiologists alike may benefit from a working knowledge of imaging studies applicable to the diagnosis and prognosis of CVD and CVD risk - both important in preventive cardiology.