Composition of Carotid Atherosclerotic Plaque Is Associated With Cardiovascular Outcome

Arterial Adventitial Vasa Vasorum Hyperplasia involved in Atherosclerotic Plaque Formation in a Rabbit Model

OBJECTIVE

It was previously believed that atherosclerotic (AS) plaque starts to develop from the intima and that intraplaque vasa vasorum (VV) hyperplasia promotes adventitial VV (AVV) hyperplasia. However, recent studies have shown that arterial AVV hyperplasia precedes early intimal thickening, suggesting its possible role as an initiating factor of AS. To provide further insight into this process, in this study, we examine the evolution of AAV and VV development in a preclinical model of early AS with longitudinal ultrasound imaging.

METHODS

Models of early AS were established. Duplex ultrasound scanning and contrast-enhanced ultrasound were performed for diagnosis. Pearson correlation tests were used to analyze the relationships between AVV hyperplasia and VV hyperplasia, or between AVV hyperplasia and intima-media thickness (IMT).

RESULTS

During 0-12 wk of high-fat feeding, AVV gradually increased and intima-media thickened gradually in the observation area; in the 2nd wk of high-fat feeding, the observation area showed obvious AVV proliferation; at the 4th wk, the intima-media membrane became thicker; at the 12th wk, early plaque formation and intraplaque VV proliferation were observed. There was a strong positive correlation between AVV proliferation and IMT thickening and a strong negative correlation between AVV proliferation and the change rate of vessel diameter.

CONCLUSION

This study demonstrated that AVV proliferation in the arteries occurred earlier than IMT thickening and was positively correlated with IMT. At present, the indicators of ultrasonic diagnosis of AS, such as IMT, Intraplaque VV, Echo property, all appear in the advanced stage of AS. The AVV may be an innovative diagnostic target for the early stage of AS plaque.

Genome-scale metabolic network of human carotid plaque reveals the pivotal role of glutamine/glutamate metabolism in macrophage modulating plaque inflammation and vulnerability

BACKGROUND

Metabolism is increasingly recognized as a key regulator of the function and phenotype of the primary cellular constituents of the atherosclerotic vascular wall, including endothelial cells, smooth muscle cells, and inflammatory cells. However, a comprehensive analysis of metabolic changes associated with the transition of plaque from a stable to a hemorrhaged phenotype is lacking.

METHODS

In this study, we integrated two large mRNA expression and protein abundance datasets (BIKE, n = 126; MaasHPS, n = 43) from human atherosclerotic carotid artery plaque to reconstruct a genome-scale metabolic network (GEM). Next, the GEM findings were linked to metabolomics data from MaasHPS, providing a comprehensive overview of metabolic changes in human plaque.

RESULTS

Our study identified significant changes in lipid, cholesterol, and inositol metabolism, along with altered lysosomal lytic activity and increased inflammatory activity, in unstable plaques with intraplaque hemorrhage (IPH+) compared to non-hemorrhaged (IPH-) plaques. Moreover, topological analysis of this network model revealed that the conversion of glutamine to glutamate and their flux between the cytoplasm and mitochondria were notably compromised in hemorrhaged plaques, with a significant reduction in overall glutamate levels in IPH+ plaques. Additionally, reduced glutamate availability was associated with an increased presence of macrophages and a pro-inflammatory phenotype in IPH+ plaques, suggesting an inflammation-prone microenvironment.

CONCLUSIONS

This study is the first to establish a robust and comprehensive GEM for atherosclerotic plaque, providing a valuable resource for understanding plaque metabolism. The utility of this GEM was illustrated by its ability to reliably predict dysregulation in the cholesterol hydroxylation, inositol metabolism, and the glutamine/glutamate pathway in rupture-prone hemorrhaged plaques, a finding that may pave the way to new diagnostic or therapeutic measures.

The guardian of intracranial vessels: Why the pericyte?

Intracranial atherosclerotic stenosis (ICAS) is a pathological condition characterized by progressive narrowing or complete blockage of intracranial blood vessels caused by plaque formation. This condition leads to reduced blood flow to the brain, resulting in cerebral ischemia and hypoxia. Ischemic stroke (IS) resulting from ICAS poses a significant global public health challenge, especially among East Asian populations. However, the underlying causes of the notable variations in prevalence among diverse populations, as well as the most effective strategies for preventing and treating the rupture and blockage of intracranial plaques, remain incompletely comprehended. Rupture of plaques, bleeding, and thrombosis serve as precipitating factors in the pathogenesis of luminal obstruction in intracranial arteries. Pericytes play a crucial role in the structure and function of blood vessels and face significant challenges in regulating the Vasa Vasorum (VV)and preventing intraplaque hemorrhage (IPH). This review aims to explore innovative therapeutic strategies that target the pathophysiological mechanisms of vulnerable plaques by modulating pericyte biological function. It also discusses the potential applications of pericytes in central nervous system (CNS) diseases and their prospects as a therapeutic intervention in the field of biological tissue engineering regeneration.

The Impact of HIFU Ablation on the Histopathological Features of Locally Recurrent Fibroids Tissue Post-HIFU Treatment

OBJECTIVE

To evaluate the impact of high-intensity focused ultrasound (HIFU) ablation on the histopathological features of locally recurrent fibroids tissue.

METHODS

Patients who underwent transabdominal hysterectomy or myomectomy for uterine fibroids from January 1, 2021 to July 1, 2023 at a teaching hospital in China were enrolled in this prospective study. The patients who underwent surgery for local recurrence of uterine fibroids after HIFU ablation were categorized as the HIFU group, and patients who had not undergone HIFU ablation for uterine fibroids were the control group. Hematoxylin-eosin (HE) staining, Masson staining, and immunohistochemical staining were performed to analyze the counts of smooth muscle cells (SMCs), collagen content, microvascular count, and the expression levels of estrogen receptor (ER) and progesterone receptor (PR) in the fibroid tissue specimens.

RESULTS

The mean SMC counts in the HIFU and control groups were 337.68/field and 328.52/field respectively. The mean collagen content in the HIFU group and control group were 46.06% and 41.69% respectively. The mean microvessel counts in the HIFU group and control group were 13.66/field and 14.08/field respectively. The mean ER scores in the HIFU and control groups were 6.9 and 7.47 respectively, and the mean PR scores were 7.3 and 7.56 respectively. Overall, there were no significant differences in the SMC counts, collagen content, microvascular counts, and the ER and PR expression levels between the HIFU group and control group (p > 0.05).

CONCLUSIONS

HIFU ablation has no effect on the pathological characteristics of local recurrent fibroid tissue, and is an ideal non-invasive treatment option.

Atherosclerotic Plaque Epigenetic Age Acceleration Predicts a Poor Prognosis and Is Associated With Endothelial-to-Mesenchymal Transition in Humans

BACKGROUND

Epigenetic age estimators (clocks) are predictive of human mortality risk. However, it is not yet known whether the epigenetic age of atherosclerotic plaques is predictive for the risk of cardiovascular events.

METHODS

Whole-genome DNA methylation of human carotid atherosclerotic plaques (n=485) and of blood (n=93) from the Athero-Express endarterectomy cohort was used to calculate epigenetic age acceleration (EAA). EAA was linked to clinical characteristics, plaque histology, and future cardiovascular events (n=136). We studied whole-genome DNA methylation and bulk and single-cell transcriptomics to uncover molecular mechanisms of plaque EAA. We experimentally confirmed our in silico findings using in vitro experiments in primary human coronary endothelial cells.

RESULTS

Male and female patients with severe atherosclerosis had a median chronological age of 69 years. The median epigenetic age was 65 years in females (median EAA, -2.2 [interquartile range, -4.3 to 2.2] years) and 68 years in males (median EAA, -0.3 [interquartile range, -2.9 to 3.8] years). Patients with diabetes and a high body mass index had higher plaque EAA. Increased EAA of plaque predicted future events in a 3-year follow-up in a Cox regression model (univariate hazard ratio, 1.7; P=0.0034) and adjusted multivariate model (hazard ratio, 1.56; P=0.02). Plaque EAA predicted outcome independent of blood EAA (hazard ratio, 1.3; P=0.018) and of plaque hemorrhage (hazard ratio, 1.7; P=0.02). Single-cell RNA sequencing in plaque samples from 46 patients in the same cohort revealed smooth muscle and endothelial cells as important cell types in plaque EAA. Endothelial-to-mesenchymal transition was associated with EAA, which was experimentally confirmed by TGFβ-triggered endothelial-to-mesenchymal transition inducing rapid epigenetic aging in coronary endothelial cells.

CONCLUSIONS

Plaque EAA is a strong and independent marker of poor outcome in patients with severe atherosclerosis. Plaque EAA was linked to mesenchymal endothelial and smooth muscle cells. Endothelial-to-mesenchymal transition was associated with EAA, which was experimentally validated. Epigenetic aging mechanisms may provide new targets for treatments that reduce atherosclerosis complications.

Molecular Pathways of Vulnerable Carotid Plaques at Risk of Ischemic Stroke: A Narrative Review

The concept of vulnerable carotid plaques is pivotal in understanding the pathophysiology of ischemic stroke secondary to large-artery atherosclerosis. In macroscopic evaluation, vulnerable plaques are characterized by one or more of the following features: microcalcification; neovascularization; lipid-rich necrotic cores (LRNCs); intraplaque hemorrhage (IPH); thin fibrous caps; plaque surface ulceration; huge dimensions, suggesting stenosis; and plaque rupture. Recognizing these macroscopic characteristics is crucial for estimating the risk of cerebrovascular events, also in the case of non-significant (less than 50%) stenosis. Inflammatory biomarkers, such as cytokines and adhesion molecules, lipid-related markers like oxidized low-density lipoprotein (LDL), and proteolytic enzymes capable of degrading extracellular matrix components are among the key molecules that are scrutinized for their associative roles in plaque instability. Through their quantification and evaluation, these biomarkers reveal intricate molecular cross-talk governing plaque inflammation, rupture potential, and thrombogenicity. The current evidence demonstrates that plaque vulnerability phenotypes are multiple and heterogeneous and are associated with many highly complex molecular pathways that determine the activation of an immune-mediated cascade that culminates in thromboinflammation. This narrative review provides a comprehensive analysis of the current knowledge on molecular biomarkers expressed by symptomatic carotid plaques. It explores the association of these biomarkers with the structural and compositional attributes that characterize vulnerable plaques.

A critical appreciation of pathway analysis in atherosclerotic disease. Cellular phenotypic plasticity as an illustrative example

The rapid advancements in genome-scale (omics) techniques has created significant opportunities to investigate complex disease mechanisms in tissues and cells. Nevertheless, interpreting -omics data can be challenging, and pathway enrichment analysis is a frequently used method to identify candidate molecular pathways that drive gene expression changes. With a growing number of -omics studies dedicated to atherosclerosis, there has been a significant increase in studies and hypotheses relying on enrichment analysis. This brief review discusses the benefits and limitations of pathway enrichment analysis within atherosclerosis research. We highlight the challenges of identifying complex biological processes, such as cell phenotypic switching, within -omics data. Additionally, we emphasize the need for more comprehensive and curated gene sets that reflect the biological complexity of atherosclerosis. Pathway enrichment analysis is a valuable tool for gaining insights into the molecular mechanisms of atherosclerosis. Nevertheless, it is crucial to remain aware of the intrinsic limitations of this approach. By addressing these weaknesses, enrichment analysis in atherosclerosis can lead to breakthroughs in identifying the mechanisms of disease progresses, the identification of key driver genes, and consequently, advance personalized patient care.

Similar long-term outcomes for venous, bovine pericardial, and polyester patches for primary carotid endarterectomy

BACKGROUND

Currently, the type of patch used for carotid endarterectomy closure depends on the preference of the operating surgeon. Various materials are available, including autologous venous patches, bovine pericardial patches (BPP), and synthetic patches. The purpose of this study was to compare the long-term outcomes.

METHODS

All patients who underwent primary carotid endarterectomy with patch angioplasty using a venous, bovine, or polyester patch between 2010 and 2020 at two high-volume medical centers were included in this retrospective analysis on largely prospectively collected data. Study endpoints included long-term ipsilateral transient ischemic attack or cerebrovascular accident, restenosis, reintervention, and all-cause mortality. Cox proportional hazard models were fitted to assess the effect of patch type to each outcome.

RESULTS

In total, 1481 CEAs were performed with a follow-up of 32 (13-65) months. Venous patch was used in 309 patients (20.9%), BPP in 1000 patients (67.5%), and polyester patch in 172 patients (11.6%). A preoperative symptomatic carotid artery stenosis of >50% was observed in 91.9% (n = 284) of the patients who received a venous patch, 92.1% (n = 921) of the patients who received BPP, and 90.7% (n = 156) of the patients who received a polyester patch (p = 0.799). Only in selected patients with an asymptomatic stenosis of >70% surgery was considered. Multivariable analyses showed no significant differences between the three patch types regarding long-term outcomes after adjusting for confounders.

CONCLUSIONS

In patients undergoing primary carotid endarterectomy, the use of venous, bovine pericardial, or polyester patches seems equally safe and durable in terms of comparability in long-term outcomes.

Melatonin inhibits the formation of intraplaque neovessels in ApoE-/- mice via PPARγ- RhoA-ROCK pathway

BACKGROUND

According to former research, the atherosclerotic plaque is thought to be aggravated by intraplaque neovessels (IPN) and intraplaque hemorrhage (IPH). Intriguingly, a lower incidence of IPH was found in plaque treated with melatonin. In this study, we attempted to investigate the impact and underlying mechanism regarding the influences of melatonin upon IPN.

METHODS

A mouse model was established by subjecting the high fat diet (HFD)-fed ApoE-/- mice to tandem stenosis (TS) surgery with melatonin and GW9662, a PPARγ antagonist, being given by gavage. In vitro experiment was conducted with HUVECs exposing to according treatments of VEGF, melatonin, GW9662, or Y27632.

RESULTS

Plaque and IPN were attenuated by treatment with melatonin, which was then reversed by blocking PPARγ. Western blotting results showed that melatonin increased PPARγ and decreased RhoA/ROCK signaling in carotid artery. Elevated RhoA/ROCK signaling was observed in melatonin-treated mice when PPARγ was blocked. In accordance with it, experiments using protein and mRNA from HUVECs revealed that melatonin inhibited the RhoA/ROCK signaling by enhancing PPARγ. According to in vitro study, melatonin was able to inhibit cell migration and angiogenesis, which was aborted by GW9662. Blockage of ROCK using Y27632 was able to cease the effect of GW9662 and restored the suppression on cell migration and angiogenesis by melatonin.

CONCLUSIONS

Our study demonstrates that melatonin is able to curb development of plaque and IPN formation by inhibiting the migration of endothelial cells via PPARγ- RhoA-ROCK pathway. That provides a therapeutic potential for both melatonin and PPARγ agonist targeting IPN, IPH, and atherosclerotic plaque.

Atherosclerotic plaque development in mice is enhanced by myeloid ZEB1 downregulation

Accumulation of lipid-laden macrophages within the arterial neointima is a critical step in atherosclerotic plaque formation. Here, we show that reduced levels of the cellular plasticity factor ZEB1 in macrophages increase atherosclerotic plaque formation and the chance of cardiovascular events. Compared to control counterparts (Zeb1WT/ApoeKO), male mice with Zeb1 ablation in their myeloid cells (Zeb1∆M/ApoeKO) have larger atherosclerotic plaques and higher lipid accumulation in their macrophages due to delayed lipid traffic and deficient cholesterol efflux. Zeb1∆M/ApoeKO mice display more pronounced systemic metabolic alterations than Zeb1WT/ApoeKO mice, with higher serum levels of low-density lipoproteins and inflammatory cytokines and larger ectopic fat deposits. Higher lipid accumulation in Zeb1∆M macrophages is reverted by the exogenous expression of Zeb1 through macrophage-targeted nanoparticles. In vivo administration of these nanoparticles reduces atherosclerotic plaque formation in Zeb1∆M/ApoeKO mice. Finally, low ZEB1 expression in human endarterectomies is associated with plaque rupture and cardiovascular events. These results set ZEB1 in macrophages as a potential target in the treatment of atherosclerosis.

GM-CSF-activated STAT5A regulates macrophage functions and inflammation in atherosclerosis

Introduction

Inhibition of STAT5 was recently reported to reduce murine atherosclerosis. However, the role of STAT5 isoforms, and more in particular STAT5A in macrophages in the context of human atherosclerosis remains unknown.

Methods and results

Here, we demonstrate reciprocal expression regulation of STAT5A and STAT5B in human atherosclerotic lesions. The former was highly upregulated in ruptured over stable plaque and correlated with macrophage presence, a finding that was corroborated by the high chromosomal accessibility of STAT5A but not B gene in plaque macrophages. Phosphorylated STAT5 correlated with macrophages confirming its activation status. As macrophage STAT5 is activated by GM-CSF, we studied the effects of its silencing in GM-CSF differentiated human macrophages. STAT5A knockdown blunted the immune response, phagocytosis, cholesterol metabolism, and augmented apoptosis terms on transcriptional levels. These changes could partially be confirmed at functional level, with significant increases in apoptosis and decreases in lipid uptake and IL-6, IL-8, and TNFa cytokine secretion after STAT5A knockdown. Finally, inhibition of general and isoform A specific STAT5 significantly reduced the secretion of TNFa, IL-8 and IL-10 in ex vivo tissue slices of advanced human atherosclerotic plaques.

Discussion

In summary, we identify STAT5A as an important determinant of macrophage functions and inflammation in the context of atherosclerosis and show its promise as therapeutic target in human atherosclerotic plaque inflammation.

The accumulation of erythrocytes quantified and visualized by Glycophorin C in carotid atherosclerotic plaque reflects intraplaque hemorrhage and pre-procedural neurological symptoms

The accumulation of erythrocyte membranes within an atherosclerotic plaque may contribute to the deposition of free cholesterol and thereby the enlargement of the necrotic core. Erythrocyte membranes can be visualized and quantified in the plaque by immunostaining for the erythrocyte marker glycophorin C. Hence, we theorized that the accumulation of erythrocytes quantified by glycophorin C could function as a marker for plaque vulnerability, possibly reflecting intraplaque hemorrhage (IPH), and offering predictive value for pre-procedural neurological symptoms. We employed the CellProfiler-integrated slideToolKit workflow to visualize and quantify glycophorin C, defined as the total plaque area that is positive for glycophorin C, in single slides of culprit lesions obtained from the Athero-Express Biobank of 1819 consecutive asymptomatic and symptomatic patients who underwent carotid endarterectomy. Our assessment included the evaluation of various parameters such as lipid core, calcifications, collagen content, SMC content, and macrophage burden. These parameters were evaluated using a semi-quantitative scoring method, and the resulting data was dichotomized as predefined criteria into categories of no/minor or moderate/heavy staining. In addition, the presence or absence of IPH was also scored. The prevalence of IPH and pre-procedural neurological symptoms were 62.4% and 87.1%, respectively. The amount of glycophorin staining was significantly higher in samples from men compared to samples of women (median 7.15 (IQR:3.37, 13.41) versus median 4.06 (IQR:1.98, 8.32), p < 0.001). Glycophorin C was associated with IPH adjusted for clinical confounders (OR 1.90; 95% CI 1.63, 2.21; p =  < 0.001). Glycophorin C was significantly associated with ipsilateral pre-procedural neurological symptoms (OR:1.27, 95%CI:1.06-1.41, p = 0.005). Sex-stratified analysis, showed that this was also the case for men (OR 1.37; 95%CI 1.12, 1.69; p = 0.003), but not for women (OR 1.15; 95%CI 0.77, 1.73; p = 0.27). Glycophorin C was associated with classical features of a vulnerable plaque, such as a larger lipid core, a higher macrophage burden, less calcifications, a lower collagen and SMC content. There were marked sex differences, in men, glycophorin C was associated with calcifications and collagen while these associations were not found in women. To conclude, the accumulation of erythrocytes in atherosclerotic plaque quantified and visualized by glycophorin C was independently associated with the presence of IPH, preprocedural symptoms in men, and with a more vulnerable plaque composition in both men and women. These results strengthen the notion that the accumulation of erythrocytes quantified by glycophorin C can be used as a marker for plaque vulnerability.

The Ultrasound Window Into Vascular Ageing: A Technology Review by the VascAgeNet COST Action

Non-invasive ultrasound (US) imaging enables the assessment of the properties of superficial blood vessels. Various modes can be used for vascular characteristics analysis, ranging from radiofrequency (RF) data, Doppler- and standard B/M-mode imaging, to more recent ultra-high frequency and ultrafast techniques. The aim of the present work was to provide an overview of the current state-of-the-art non-invasive US technologies and corresponding vascular ageing characteristics from a technological perspective. Following an introduction about the basic concepts of the US technique, the characteristics considered in this review are clustered into: 1) vessel wall structure; 2) dynamic elastic properties, and 3) reactive vessel properties. The overview shows that ultrasound is a versatile, non-invasive, and safe imaging technique that can be adopted for obtaining information about function, structure, and reactivity in superficial arteries. The most suitable setting for a specific application must be selected according to spatial and temporal resolution requirements. The usefulness of standardization in the validation process and performance metric adoption emerges. Computer-based techniques should always be preferred to manual measures, as long as the algorithms and learning procedures are transparent and well described, and the performance leads to better results. Identification of a minimal clinically important difference is a crucial point for drawing conclusions regarding robustness of the techniques and for the translation into practice of any biomarker.

Chaperone-mediated autophagy: Molecular mechanisms, biological functions, and diseases

Chaperone-mediated autophagy (CMA) is a lysosomal degradation pathway that eliminates substrate proteins through heat-shock cognate protein 70 recognition and lysosome-associated membrane protein type 2A-assisted translocation. It is distinct from macroautophagy and microautophagy. In recent years, the regulatory mechanisms of CMA have been gradually enriched, including the newly discovered NRF2 and p38-TFEB signaling, as positive and negative regulatory pathways of CMA, respectively. Normal CMA activity is involved in the regulation of metabolism, aging, immunity, cell cycle, and other physiological processes, while CMA dysfunction may be involved in the occurrence of neurodegenerative disorders, tumors, intestinal disorders, atherosclerosis, and so on, which provides potential targets for the treatment and prediction of related diseases. This article describes the general process of CMA and its role in physiological activities and summarizes the connection between CMA and macroautophagy. In addition, human diseases that concern the dysfunction or protective role of CMA are discussed. Our review deepens the understanding of the mechanisms and physiological functions of CMA and provides a summary of past CMA research and a vision of future directions.

Pim Kinases: Important Regulators of Cardiovascular Disease

Pim Kinases; Pim-1, Pim-2, and Pim-3, are a family of constitutively active serine/threonine kinases, widely associated with cell survival, proliferation, and migration. Historically considered to be functionally redundant, independent roles for the individual isoforms have been described. Whilst most established for their role in cancer progression, there is increasing evidence for wider pathological roles of Pim kinases within the context of cardiovascular disease, including inflammation, thrombosis, and cardiac injury. The Pim kinase isoforms have widespread expression in cardiovascular tissues, including the heart, coronary artery, aorta, and blood, and have been demonstrated to be upregulated in several co-morbidities/risk factors for cardiovascular disease. Pim kinase inhibition may thus be a desirable therapeutic for a multi-targeted approach to treat cardiovascular disease and some of the associated risk factors. In this review, we discuss what is known about Pim kinase expression and activity in cells of the cardiovascular system, identify areas where the role of Pim kinase has yet to be fully explored and characterised and review the suitability of targeting Pim kinase for the prevention and treatment of cardiovascular events in high-risk individuals.

X chromosome inactivation skewing is common in advanced carotid atherosclerotic lesions in females and predicts secondary peripheral artery events

BACKGROUND AND AIM

Sex differences in atherosclerosis have been described with female plaques being mostly perceived as stable and fibrous. Sex-specific mechanisms such as mosaic loss of the Y chromosome in men have been linked to cardiovascular health. In women, X-linked mechanisms such as X chromosome inactivation (XCI) skewing is common in several tissues. Yet, information on the role of XCI in female atherosclerotic plaques is lacking. Here, we investigated the presence of XCI skewing in advanced atherosclerotic lesions and its association with cardiovascular risk factors, histological plaque data, and clinical data.

METHODS

XCI skewing was quantified in 154 atherosclerotic plaque and 55 blood DNA samples of women included in the Athero-Express study. The skewing status was determined performing the HUMARA assay. Then, we studied the relationship of XCI skewing in female plaque and cardiovascular risk factors using regression models. In addition, we studied if plaque XCI predicted plaque composition, and adverse events during 3-years follow-up using Cox proportional hazard models.

RESULTS

XCI skewing was detected in 76 of 154 (49.4%) plaques and in 27 of 55 (67%) blood samples. None of the clinical risk factors were associated with plaque skewing. Plaque skewing was more often detected in plaques with a plaque hemorrhage (OR [95% CI]: 1.44 [1.06-1.98], P = 0.02). Moreover, skewed plaques were not associated with a higher incidence of composite and major events but were specifically associated with peripheral artery events during a 3-year follow-up period in a multivariate model (HR [95%CI]: 1.46 [1.09-1.97]; P = 0.007).

CONCLUSIONS

XCI skewing is common in carotid plaques of females and is predictive for the occurrence of peripheral artery events within 3 years after carotid endarterectomy.

Novel theranostic approaches to neovascularized atherosclerotic plaques

As the global burden of atherosclerotic cardiovascular disease continues to rise, there is an increased demand for improved imaging techniques for earlier detection of atherosclerotic plaques and new therapeutic targets. Plaque lesions, vulnerable to rupture and thrombosis, are thought to be responsible for the majority of cardiovascular events, and are characterized by a large lipid core, a thin fibrous cap, and neovascularization. In addition to supplying the plaque core with increased inflammatory factors, these pathological neovessels are tortuous and leaky, further increasing the risk of intraplaque hemorrhage. Clinically, plaque neovascularization has been shown to be a significant and independent predictor of adverse cardiovascular outcomes. Microvessels can be detected through contrast-enhanced ultrasound (CEUS) imaging, however, clinical assessment in vivo is generally limited to qualitative measures of plaque neovascularization. There is no validated standard for quantitative assessment of the microvessel networks found in plaques. Advances in our understanding of the pathological mechanisms underlying plaque neovascularization and its significant role in the morbidity and mortality associated with atherosclerosis have made it an attractive area of research in translational medicine. Current areas of research include the development of novel therapeutic and diagnostic agents to target plaque neovascularization stabilization. With recent progress in nanotechnology, nanoparticles have been investigated for their ability to specifically target neovascularization. Contrast microbubbles have been similarly engineered to carry loads of therapeutic agents and can be visualized using CEUS. This review summarizes the pathogenesis, diagnosis, clinical significance of neovascularization, and importantly the emerging areas of theranostic tool development.

Characteristics of peripheral blood cells are independently related to major adverse cardiovascular events after carotid endarterectomy

Background and aims

Patients who underwent carotid endarterectomy (CEA) still have a residual risk of 13% of developing a major adverse cardiovascular event (MACE) within 3 years. Inflammatory processes leading up to MACE are not fully understood. Therefore, we examined blood cell characteristics (BCCs), possibly reflecting inflammatory processes, in relation to MACE to identify BCCs that may contribute to an increased risk.

Methods

We analyzed 75 pretreatment BCCs from the Sapphire analyzer, and clinical data from the Athero-Express biobank in relation to MACE after CEA using Random Survival Forests, and a Generalized Additive Survival Model. To understand biological mechanisms, we related the identified variables to intraplaque hemorrhage (IPH).

Results

Of 783 patients, 97 (12%) developed MACE within 3 years after CEA. Red blood cell distribution width (RDW) (HR 1.23 [1.02, 1.68], p = 0.022), CV of lymphocyte size (LACV) (HR 0.78 [0.63, 0.99], p = 0.043), neutrophil complexity of the intracellular structure (NIMN) (HR 0.80 [0.64, 0.98], p = 0.033), mean neutrophil size (NAMN) (HR 0.67 [0.55, 0.83], p < 0.001), mean corpuscular volume (MCV) (HR 1.35 [1.09, 1.66], p = 0.005), eGFR (HR 0.65 [0.52, 0.80], p < 0.001); and HDL-cholesterol (HR 0.62 [0.45, 0.85], p = 0.003) were related to MACE. NAMN was related to IPH (OR 0.83 [0.71-0.98], p = 0.02).

Conclusions

This is the first study to present a higher RDW and MCV and lower LACV, NIMN and NAMN as biomarkers reflecting inflammatory processes that may contribute to an increased risk of MACE after CEA.

Plasma Lipoprotein Lipase Is Associated with Risk of Future Major Adverse Cardiovascular Events in Patients Following Carotid Endarterectomy

INTRODUCTION

Carotid plaque intraplaque haemorrhage (IPH) is associated with future cardiovascular events. It was hypothesised that plasma proteins associated with carotid plaque IPH are also likely to be associated with major adverse cardiovascular events (MACE) after carotid endarterectomy (CEA).

METHODS

In pre-operative blood samples from patients undergoing CEA within the Athero-Express biobank, proteins involved in cardiovascular disease were measured using three OLINK proteomics immunoassays. The association between proteins and IPH was analysed using logistic regression analyses. Subsequently, the association between the IPH associated plasma proteins and the three year post-operative risk of MACE (including stroke, myocardial infarction, or cardiovascular death) was analysed.

RESULTS

Within the three year follow up, 130 patients (18.9%) of 688 symptomatic and asymptomatic patients undergoing CEA developed MACE. Six of 276 plasma proteins were found to be significantly associated with IPH, from which only lipoprotein lipase (LPL) was associated with the post-operative risk of MACE undergoing CEA. Within the 30 day peri-operative period, high plasma LPL was independently associated with an increased risk of MACE (adjusted hazard ratio [HR] per standard deviation [SD] 1.60, 1.10 - 2.30), p = .014). From 30 days to three years, however, high LPL was associated with a lower risk of MACE (adjusted HR per SD 0.80, 0.65 - 0.99, p= .036).

CONCLUSION

High LPL concentrations were found to be associated with a higher risk of MACE in the first 30 post-operative days but with a lower risk MACE between 30 days and three years, meaning that LPL has different hazards at different time points.

Pulse wave and vector flow Imaging for atherosclerotic disease progression in hypercholesterolemic swine

Non-invasive monitoring of atherosclerosis remains challenging. Pulse Wave Imaging (PWI) is a non-invasive technique to measure the local stiffness at diastolic and end-systolic pressures and quantify the hemodynamics. The objective of this study is twofold, namely (1) to investigate the capability of (adaptive) PWI to assess progressive change in local stiffness and homogeneity of the carotid in a high-cholesterol swine model and (2) to assess the ability of PWI to monitor the change in hemodynamics and a corresponding change in stiffness. Nine (n=9) hypercholesterolemic swine were included in this study and followed for up to 9 months. A ligation in the left carotid was used to cause a hemodynamic disturbance. The carotids with detectable hemodynamic disturbance showed a reduction in wall shear stress immediately after ligation (2.12 ± 0.49 to 0.98 ± 0.47 Pa for 40-90% ligation (Group B) and 1.82 ± 0.25 to 0.49 ± 0.46 Pa for >90% ligation (Group C)). Histology revealed subsequent lesion formation after 8-9 months, and the type of lesion formation was dependent on the type of the induced ligation, with more complex plaques observed in the carotids with a more significant ligation (C: >90%). The compliance progression appears differed for groups B and C, with an increase in compliance to 2.09 ± 2.90×10-10 m2 Pa-1 for group C whereas the compliance of group B remained low at 8 months (0.95 ± 0.94×10-10 m2 Pa-1). In summary, PWI appeared capable of monitoring a change in wall shear stress and separating two distinct progression pathways resulting in distinct compliances.

An automatic entropy method to efficiently mask histology whole-slide images

Tissue segmentation of histology whole-slide images (WSI) remains a critical task in automated digital pathology workflows for both accurate disease diagnosis and deep phenotyping for research purposes. This is especially challenging when the tissue structure of biospecimens is relatively porous and heterogeneous, such as for atherosclerotic plaques. In this study, we developed a unique approach called 'EntropyMasker' based on image entropy to tackle the fore- and background segmentation (masking) task in histology WSI. We evaluated our method on 97 high-resolution WSI of human carotid atherosclerotic plaques in the Athero-Express Biobank Study, constituting hematoxylin and eosin and 8 other staining types. Using multiple benchmarking metrics, we compared our method with four widely used segmentation methods: Otsu's method, Adaptive mean, Adaptive Gaussian and slideMask and observed that our method had the highest sensitivity and Jaccard similarity index. We envision EntropyMasker to fill an important gap in WSI preprocessing, machine learning image analysis pipelines, and enable disease phenotyping beyond the field of atherosclerosis.

Extracellular vesicles and atherosclerotic peripheral arterial disease

Atherogenesis involves a complex multifactorial process including chronic inflammation that requires the participation of several cell types and molecules. In addition to their role in vascular homeostasis, extracellular vesicles also appear to play an important role in atherogenesis, including monocyte transmigration and foam cell formation, SMC proliferation and migration, leukocyte transmigration, and thrombosis. Peripheral arterial disease, a major form of peripheral vascular disease, is characterized by structural or functional impairment of peripheral arterial supply, often secondary to atherosclerosis. Elevated levels of extracellular vesicles have been demonstrated in patients with peripheral arterial disease and implicated in the development of atherosclerosis within peripheral vascular beds. However, extracellular vesicles also appear capable of delivering cargo with atheroprotective effects. This capability has been exploited in vesicles engineered to carry content capable of neovascularization, suggesting potential for therapeutic angiogenesis. This dual capacity holds substantial promise for diagnosis and therapy, including possibly limb- and life-saving options for peripheral arterial disease management.

Components of carotid atherosclerotic plaque in spectral photon-counting CT with histopathologic comparison

OBJECTIVES

This study aimed to demonstrate the effectiveness of spectral photon-counting CT (SPCCT) in quantifying fibrous cap (FC) thickness, FC area, and lipid-rich necrotic core (LRNC) area, in excised carotid atherosclerotic plaques by comparing it with histopathological measurements.

METHODS

This is a single-center ex vivo cross-sectional observational study. Excised plaques of 20 patients (71 +/- 6 years; 13 men), obtained from carotid endarterectomy were scanned with SPCCT using standardized acquisition settings (120k Vp/19 μA; 7-18 keV, 18-30 keV, 30-45 keV, 45-75 keV, and 75-118 keV). FC thickness, FC area, and LRNC area were quantified and compared between high-resolution 3D multi-energy CT images and histopathology using the Wilcoxon signed-ranks test and Bland-Altman analysis. Images were interpreted twice by two radiologists separately, blinded to the histopathology; inter- and intra-rater reliability were assessed with the intra-class correlation coefficients (ICC).

RESULTS

FC thickness and FC area did not show significant differences between the SPCCT-derived radiological measurements versus the histopathological measurements (p value range 0.15-0.51 for FC thickness and 0.053-0.30 for FC area). For the LRNC area, the p value was statistically non-significant for reader 1 (range 0.36-0.81). The Bland-Altman analysis showed mean difference and 95% confidence interval for FC thickness, FC area, and LRNC area, 0.04 (-0.36 to 0.12) square root mm, -0.18 (-0.34 to -0.02) log₁₀ mm² and 0.10 (-0.088. to 0.009) log₁₀ mm² respectively.

CONCLUSION

The result demonstrated a viable technique for quantifying FC thickness, FC area, and LRNC area due to the combined effect of high spatial and energy resolution of SPCCT.

KEY POINTS

• SPCCT can identify and quantify different components of carotid atherosclerotic plaque in ex vivo study. • Components of atherosclerotic plaque did not show significant differences between the SPCCT-derived radiological measurements versus the histopathological measurements.

Intraplaque neovascularisation is associated with ischaemic events after carotid artery stenting: an observational prospective study

Background

Intraplaque neovascularisation (IPN) is a component of vulnerable atherosclerotic plaque, which is a biomarker of cardiovascular events. However, the identification of patients with high probability of ischaemic events after carotid artery stenting (CAS) is mainly based on vascular risk factors. Prospective studies on the development of plaques are lacking.

Objectives

The purpose of this study was to investigate whether IPN detected by contrast-enhanced ultrasound is related to the occurrence of ischaemic events after CAS.

Methods

Sixty consecutive patients receiving CAS were prospectively enrolled in our centre. The patients were evaluated using contrast-enhanced ultrasound before CAS. According to the degree of microbubble enhancement, IPN was graded from 0 to 2. Endpoint events, including ischaemic stroke and other cardiovascular events, were recorded during follow-up. Kaplan-Meier survival curves and Cox proportional-hazards models were used to evaluate the risk factors for endpoint events. At a median follow-up of 30 months, 13 patients (28.9%) experienced endpoint events. Kaplan-Meier survival curves showed that patients with grade 2 IPN had a higher risk of future ischaemic events than those with grade 0 or 1 IPN (p < 0.05). Cox proportional-hazards models showed that grade 2 IPN [adjusted hazard ratio (HR), 4.049; 95% confidence interval (CI), 1.078-15.202] was a significant predictor of endpoint events (p < 0.05).

Conclusion

Grade 2 IPN evaluated by contrast-enhanced ultrasound has predictive value for ischaemic events in patients after CAS and may help clinicians identify high-risk patients who need close follow-up.

Plain Language Summary

Neovascularisation and carotid artery stenting Introduction: Introduction: It is unclear whether intraplaque neovascularisation (IPN) can be used as an biomarker of high probability ischemic events after carotid artery stenting (CAS).Materials and methods: We enrolled 60 patients who underwent CAS, all of whom underwent CEUS before CAS. We recorded ischaemic events during follow-up. Cox proportional-hazards models were used to evaluate the risk factors for ischaemic events.Results: We found that grade 2 IPN was an independent predictor (hazard ratio, 4.049; 95% confidence interval, 1.078-15.202; p < 0.05) of ischaemic events in patients after CAS.Conclusion: This may help clinicians identify high-risk patients who need close follow-up.

Evidence of Carotid Atherosclerosis Vulnerability Regression in Real Life From Magnetic Resonance Imaging: Results of the MAGNETIC Prospective Study

Background Atherosclerosis vulnerability regression has been evidenced mostly in randomized clinical trials with intensive lipid-lowering therapy. We aimed to demonstrate vulnerability regression in real life, with a comprehensive quantitative method, in patients with asymptomatic mild to moderate carotid atherosclerosis on a secondary prevention program. Methods and Results We conducted a single-center prospective observational study (MAGNETIC [Magnetic Resonance Imaging as a Gold Standard for Noninvasive Evaluation of Atherosclerotic Involvement of Carotid Arteries]): 260 patients enrolled at a cardiac rehabilitation center were followed for 3 years with serial magnetic resonance imaging. Per section cutoffs (95th/5th percentiles) were derived from a sample of 20 consecutive magnetic resonance imaging scans: (1) lipid-rich necrotic core: 26% of vessel wall area; (2) intraplaque hemorrhage: 12% of vessel wall area; and (3) fibrous cap: (a) minimum thickness: 0.06 mm, (b) mean thickness: 0.4 mm, (c) projection length: 11 mm. Patients with baseline magnetic resonance imaging of adequate quality (n=247) were classified as high (n=63, 26%), intermediate (n=65, 26%), or low risk (n=119, 48%), if vulnerability criteria were fulfilled in ≥2 contiguous sections, in 1 or multiple noncontiguous sections, or in any section, respectively. Among high-risk patients, a conversion to any lower-risk status was found in 11 (17%; P=0.614) at 6 months, in 16 (25%; P=0.197) at 1 year, and in 19 (30%; P=0.009) at 3 years. Among patients showing any degree of carotid plaque vulnerability, 21 (16%; P=0.014) were diagnosed at low risk at 3 years. Conclusions This study demonstrates with a quantitative approach that vulnerability regression is common in real life. A secondary prevention program can promote vulnerability regression in asymptomatic patients in the mid to long term.

Transcriptomic-based clustering of human atherosclerotic plaques identifies subgroups with different underlying biology and clinical presentation

Histopathological studies have revealed key processes of atherosclerotic plaque thrombosis. However, the diversity and complexity of lesion types highlight the need for improved sub-phenotyping. Here we analyze the gene expression profiles of 654 advanced human carotid plaques. The unsupervised, transcriptome-driven clustering revealed five dominant plaque types. These plaque phenotypes were associated with clinical presentation and showed differences in cellular compositions. Validation in coronary segments showed that the molecular signature of these plaques was linked to coronary ischemia. One of the plaque types with the most severe clinical symptoms pointed to both inflammatory and fibrotic cell lineages. Further, we did a preliminary analysis of potential circulating biomarkers that mark the different plaques phenotypes. In conclusion, the definition of the plaque at risk for a thrombotic event can be fine-tuned by in-depth transcriptomic-based phenotyping. These differential plaque phenotypes prove clinically relevant for both carotid and coronary artery plaques and point to distinct underlying biology of symptomatic lesions.

The utility of ultrasound and computed tomography in the assessment of carotid artery plaque vulnerability-A mini review

As the burden of cardiovascular and cerebrovascular events continues to increase, emerging evidence supports the concept of plaque vulnerability as a strong marker of plaque rupture, and embolization. Qualitative assessment of the plaque can identify the degree of plaque instability. Ultrasound and computed tomography (CT) have emerged as safe and accurate techniques for the assessment of plaque vulnerability. Plaque features including but not limited to surface ulceration, large lipid core, thin fibrous cap (FC), intraplaque neovascularization and hemorrhage can be assessed and are linked to plaque instability.

Magnetic Resonance Imaging of Intraplaque Hemorrhage and Plaque Lipid Content With Continued Lipid-Lowering Therapy: Results of a Magnetic Resonance Imaging Substudy in AIM-HIGH

BACKGROUND

Intraplaque hemorrhage (IPH) is associated with plaque progression and ischemic events, and plaque lipid content (% lipid core) predicts the residual atherosclerotic cardiovascular disease risk. This study examined the impact of IPH on lipid content change in the setting of intensive lipid-lowering therapy.

METHODS

In total, 214 AIM-HIGH (Atherothrombosis Intervention in Metabolic Syndrome with Low High-Density Lipoprotein/High Triglycerides: Impact on Global Health Outcomes) participants with clinically established ASCVD and low high-density lipoprotein cholesterol received cartoid MRI at baseline and 2 years to assess changes in carotid morphology and composition. Patients were randomized to extended-release niacin or placebo, and all received simvastatin with optional ezetimibe as necessary to lower low-density lipoprotein cholesterol to 40 to 80 mg/dL. Changes in lipid content and carotid morphology were tested using the Wilcoxon signed-rank test. Differences between subjects with and without IPH and between subjects assigned extended-release niacin or placebo were tested using the Wilcoxon rank-sum test. Linear regression was used to test the association of IPH and lipid content changes after adjusting for clinical risk factors.

RESULTS

Among 156 patients (61±9 years; 81% men) with complete MRI, prior statin use: <1 year, 26%; 1 to 5 years, 37%; >5 years, 37%. Triglycerides and ApoB decreased significantly, whereas high-density lipoprotein cholesterol and ApoA1 increased significantly over time. Plaque lipid content was significantly reduced (-0.5±2.4 %/year, P = 0.017) without a significant difference between the 2 treatment groups. However, the lipid content increased in plaques with IPH but regressed in plaques without IPH (1.2±2.5 %/year versus -1.0±2.2, P = 0.006). Additionally, IPH was associated with a decrease in lumen area (-0.4±0.9 mm2/year versus 0.3±1.4, P = 0.033). IPH remained significantly associated with increase in lipid content in multivariable analysis (54.4%, 95% CI: 26.8, 88.0, P < 0.001).

CONCLUSIONS

Carotid plaques under continued intensive lipid-lowering therapy moved toward stabilization. However, plaques with IPH showed greater increases in lipid content and greater decreases in lumen area than plaques without IPH.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT01178320.

Construction of an immune-related signature for predicting the ischemic events in patients undergoing carotid endarterectomy

Background: Inflammatory responses have drawn more attention to atherosclerosis; however, the immune-related genes (IRGs) as a prognostic factor in atherosclerotic plaque remain to be fully elucidated. Here, the purpose of this study was to investigate whether the IRGs could be identified as a reliable biomarker for predicting ischemic events in patients undergoing carotid endarterectomy (CEA). Methods: Two datasets GSE97210 and GSE21545 were downloaded from the Gene Expression Omnibus (GEO) database. The dataset GSE97210 was used to explore the significant pathways and differentially expressed IRGs (DEIRGs) between plaques and controls, which were further screened to identify the prognostic DEIRGs in the GSE21545 dataset. The identification of molecular subgroups with the prognostic gene expression patterns was achieved through nonnegative matrix factorization (NMF) clustering. Functional analyses including GO, KEGG, GSVA, and GSEA analyses, and immune analyses including xCell and ssGSEA algorithms were conducted to elucidate the underlying mechanisms. The prognostic risk model was constructed using the LASSO algorithm and multivariate Cox regression analysis. Results: A total of 796 DEIRGs (including 588 upregulated and 208 downregulated) were identified. Nine prognostic DEIRGs were further screened with univariate Cox regression analysis. Two clusters with different prognosis were grouped based on the prognostic DEIRGs. Immune infiltration analysis shows that cluster 2 with a better prognosis presented with a higher immune response than cluster 1. A prognostic model based on seven IRGs (IL2RA, NR4A2, DES, ERAP2, SLPI, RASGRP1, and AGTR2) was developed and verified. Consistent with the immune analysis of the cluster, the immune infiltration in the low-risk group with a better prognosis was also more active than that in the high-risk group. Finally, a nomogram based on the seven genes was constructed, which might have future implications in clinical care. Conclusion: The expression of immune-related genes is correlated with the immune microenvironment of atherosclerotic patients and could be applied to predict the ischemic events in patients undergoing CEA accurately.

Predictors of Progression in Intraplaque Hemorrhage Volume in Patients With Carotid Atherosclerosis: A Serial Magnetic Resonance Imaging Study

Background and Purpose

This study aimed to investigate the arterial disease risk factors for the progression of intraplaque hemorrhage (IPH) in patients with carotid atherosclerosis using serial high-resolution magnetic resonance (MR) imaging.

Methods

Consecutive symptomatic patients who had MRI evidence of intraplaque hemorrhage present in the ipsilateral carotid artery with respect to the side of the brain affected by stroke or TIA were recruited in the study. All the patients underwent follow-up MR imaging at least 6 months after baseline. The annual change in IPH and other carotid plaque morphology was calculated, and a tertile method was used to classify the plaques as progressed or not with respect to IPH volume using the software CASCADE. Logistic regression and receiver operating characteristic (ROC) curve were conducted to evaluate the risk factors for the progression of IPH.

Results

A total of thirty-four symptomatic patients (mean age: 67.1 years, standard deviation [SD]: 9.8 years, 27 men) were eligible for the final analysis, and contralateral plaques containing IPH were seen in 11 of these patients (making 45 plaques with IPH in total). During mean 16.6-month (SD: 11.0 months) follow-up, the overall annual change in IPH volume in 45 plaques with IPH was mean −10.9 mm3 (SD: 49.1 mm3). Carotid plaques were significantly more likely to be classified in progressed IPH group if the patient was taking antiplatelet agent at baseline (OR: 9.76; 95%CI: 1.05 to 90.56; p = 0.045), had a baseline history of current or past smoking (OR: 9.28; 95%CI: 1.26 to 68.31; p = 0.029), or had a larger baseline carotid plaque-containing vessel wall volume (OR: 1.36 per 10 mm3; 95%CI: 1.02 to 1.81; p = 0.032) after adjustments for confounding factors. ROC analysis indicated that the combination of these three risk factors in the final model produced good discriminatory value for the progressed IPH group (area under the curve: 0.887).

Conclusions

Taking an antiplatelet agent at baseline, a baseline history of current or past smoking and larger baseline carotid plaque-containing vessel wall volume were independently predictive of plaques being in the progressed IPH group. Our findings indicate that awareness and management of such risk factors may reduce the risk of intraplaque hemorrhage progression.

Birefringent Crystals Deposition and Inflammasome Expression in Human Atheroma Plaques by Levels of Uricemia

OBJECTIVE

To verify the monosodium urate (MSU) crystal deposition in artery walls following a structure assessment and to assess NLRP3 inflammasome expression in human atheroma plaques by levels of uricemia.

METHODS

Patients with peripheral arterial disease who were candidates for amputation were recruited and classified as normouricemic or hyperuricemic. During surgery, an artery segment from the amputated limb was sampled, divided and fixed separately by cryo-embedding, 100% ethanol or Glyo-fixx. Samples were assessed by compensated polarized-light microscopy to identify MSU crystals on the artery walls. Afterwards, macrophages, neutrophils and NLRP3 inflammasome components at the plaque were categorized by immunostaining and compared between normouricemics and hyperuricemics.

RESULTS

Thirty artery samples from 27 patients were studied; 10 (37.0%) participants were hyperuricemic. Birefringent needle-shaped crystals were found in three samples (10.0%), all processed by frozen sectioning. Other methods showed no crystals. No accompanying inflammatory process was noted, and the presence of crystals was equally distributed across ranges of uricemia, making it unlikely they were MSU crystals. Regarding immunostaining, 28 artery samples were available for analysis, with similar infiltration of macrophages and neutrophils. NLRP3 and gasdermin-D expression were significantly greater in hyperuricemics compared to normouricemics (p=0.044 and p=0.017, respectively). ASC content was numerically larger in hyperuricemics as well, while caspase-1 and IL-1beta expression were similar between groups.

CONCLUSIONS

The presence of MSU crystals on artery walls was not confirmed. Hyperuricemia was associated with greater NLRP3 and gasdermin-D expression on human atheroma plaques in patients with peripheral artery disease.

Change of Heart: The Underexplored Role of Plaque Hemorrhage in the Evaluation of Stroke of Undetermined Etiology

In the evaluation of embolic strokes of undetermined source, great emphasis is often placed on cardiovascular disease, namely on atrial fibrillation. Other pathophysiologic mechanisms, however, may also be involved. Carotid artery intraplaque hemorrhage (IPH)—the presence of blood components within an atheromatous plaque—has become increasingly recognized as a possible etiologic mechanism in some cryptogenic strokes. IPH is a marker of plaque instability and is associated with ipsilateral neurologic ischemic events, even in nonstenotic carotid plaques. As recognition of carotid IPH as an etiology of embolic strokes has grown, so too has the complexity with which such patients are evaluated and treated, particularly because overlaps exist in the risk factors for atrial fibrillation and IPH. In this article, we review what is currently known about carotid IPH and how this clinical entity should be approached in the context of the evaluation of embolic strokes of undetermined source.

Protective role of chaperone-mediated autophagy against atherosclerosis

Chaperone-mediated autophagy (CMA) contributes to regulation of energy homeostasis by timely degradation of enzymes involved in glucose and lipid metabolism. Here, we report reduced CMA activity in vascular smooth muscle cells and macrophages in murine and human arteries in response to atherosclerotic challenges. We show that in vivo genetic blockage of CMA worsens atherosclerotic pathology through both systemic and cell-autonomous changes in vascular smooth muscle cells and macrophages, the two main cell types involved in atherogenesis. CMA deficiency promotes dedifferentiation of vascular smooth muscle cells and a proinflammatory state in macrophages. Conversely, a genetic mouse model with up-regulated CMA shows lower vulnerability to proatherosclerotic challenges. We propose that CMA could be an attractive therapeutic target against cardiovascular diseases.

Ceramides and phospholipids in plasma extracellular vesicles are associated with high risk of major cardiovascular events after carotid endarterectomy

Ceramides and phosphatidylcholines (PCs) are bioactive lipids and lipid bilayer membrane components. Distinct ceramides/PCs (ratios) predict cardiovascular outcome in patients with coronary artery disease. Extracellular vesicles (EVs) are proposed biomarkers for cardiovascular disease and contain ceramides/PCs. Ceramides/PCs have not been studied in patients undergoing carotid endarterectomy (CEA) nor in EVs. We therefore investigated whether levels of ceramides/PCs in plasma and EVs are associated with postoperative risk of major adverse cardiovascular events (MACE) following CEA. In 873 patients undergoing CEA of the Athero-Express biobank, we quantitatively measured seven ceramides/PCs in preoperative blood samples: Cer(d18:1/16:0), Cer(d18:1/18:0), Cer(d18:1/24:0), Cer(d18:1/24:1), PC(14:0/22:6), PC(16:0/16:0) and PC(16:0/22:5) in plasma and two plasma EV-subfractions (LDL and TEX). We analyzed the association of ceramides, PCs and their predefined ratios with the three-year postoperative risk of MACE (including stroke, myocardial infarction and cardiovascular death). A total of 138 patients (16%) developed MACE during the three-year follow-up. In the LDL-EV subfraction, higher levels of Cer(d18:1/24:1) and Cer(d18:1/16:0)/PC(16:0/22:5) ratio were significantly associated with an increased risk of MACE (adjusted HR per SD [95% CI] 1.24 [1.01–1.53] and 1.26 [1.04–1.52], respectively). In the TEX-EV subfraction, three ratios Cer(d18:1/16:0)/Cer(d18:1/24:0), Cer(d18:1/18:0)/Cer(d18:1/24:0) and Cer(d18:1/24:1)/Cer(d18:1/24:0) were positively associated with MACE (adjusted HR per SD 1.34 [1.06–1.70], 1.24 [1.01–1.51] and 1.31 [1.08–1.58], respectively). In conclusion, distinct ceramides and PCs in plasma EVs determined in preoperative blood were independently associated with an increased 3-year risk of MACE after CEA. These lipids are therefore potential markers to identify high-risk CEA patients qualifying for secondary preventive add-on therapy.

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.

Carotid Plaque Composition and Prediction of Incident Atherosclerotic Cardiovascular Disease

BACKGROUND

Whether information on carotid plaque composition contributes to prediction of incident atherosclerotic cardiovascular disease (ASCVD) remains to be investigated. We determined the sex-specific added value of carotid plaque components for predicting incident ASCVD events, beyond traditional cardiovascular risk factors.

METHODS

Between 2007 and 2012, participants from the population-based Rotterdam Study with asymptomatic carotid wall thickening >2.5 mm on ultrasonography were invited for carotid magnetic resonance imaging. Among 1349 participants (mean age: 72 years [SD±9.3], 49.5% women) without cardiovascular disease, we assessed plaque thickness, luminal stenosis (>30%), presence of intraplaque hemorrhage, lipid-rich necrotic core, and calcification. Follow-up for ASCVD was complete until January 1, 2015. Using Cox proportional hazards models, we fitted sex-specific prediction models including traditional cardiovascular risk factors (base model). We extended the base model by single and simultaneous additions of plaque characteristics and calculated improvement of model performance by the C statistics.

RESULTS

During a median follow-up of 4.8 years, 60 men and 48 women developed ASCVD. In women, presence of intraplaque hemorrhage was associated with incident ASCVD (adjusted hazard ratio, 3.37 [95% CI, 1.81-6.25]). The C statistic (95% CI) improved from 0.73 (0.66-0.79) to 0.76 (0.70-0.83) after single addition of intraplaque hemorrhage to the base model. Simultaneous addition of plaque components, plaque thickness, and stenosis did not change the results. In men, only carotid stenosis was statistically significantly associated with incident ASCVD (adjusted hazard ratio, 1.75 [95% CI, 1.00-3.08]); yet, the association diminished after the addition of other plaque characteristics, and no improvements were observed in C statistics.

CONCLUSIONS

Presence of intraplaque hemorrhage contributes to the prediction of incident ASCVD in women, beyond traditional cardiovascular risk factors, other plaque components, plaque size, and stenosis.

Differences in Vasa Vasorum Distribution in Human Aortic Aneurysms and Atheromas

The pathophysiological difference between aortic atheromas and aneurysms is unknown. We focused on the vasa vasorum (VV), which play a critical role in maintaining aortic homeostasis and are also involved in vascular diseases. We investigated the differences in VV between the atheromas and aneurysms. Human abdominal aortic samples were obtained from patients with abdominal aortic aneurysm during surgery or autopsy cases. Autopsy cases were divided into 2 groups according to atheromas. The VV were evaluated using immunohistochemical staining for von Willebrand factor. Intimal VV increased in both the atheroma and aneurysm groups, medial VV increased, and adventitial VV decreased only in the aneurysm group. We also observed that the medial VV were connected to the adventitial VV in the atheroma group and to intimal VV in the aneurysm group. We suggest the outside-in VV or inside-out VV theories. Atheroma induces hypoxia of aortic walls, and angiogenic factors might induce an increase of intimal VV derived from adventitial VV (outside-in VV). However, adventitial VV decrease induces hypoxia of aortic walls, and angiogenic factors might induce an increase of intimal VV derived from aortic lumen (inside-out VV). These differences of VV may contribute in elucidating the pathophysiology of aortic diseases.

Heme in Cardiovascular Diseases: A Ubiquitous Dangerous Molecule Worthy of Vigilance

Heme, the protoporphyrin IX iron complex is widely present in the human body and it is involved in oxygen storage, electron transfer, and enzymatic reactions. However, free heme can be toxic as it catalyzes the production of reactive oxygen species, oxidizes lipids and proteins, and causes DNA damage, thereby inducing a pro-inflammatory environment. The generation, metabolism, and degradation of heme in the human body are regulated by precise mechanisms to ensure that heme remains non-toxic. However, in several types of cardiovascular diseases, impaired metabolism and exposure to heme may occur in pathological processes, including neovascularization, internal hemorrhage, ischemia, and reperfusion. Based on years of research, in this review, we aimed to summarize the underlying mechanisms by which heme contributes to the development of cardiovascular diseases through oxidative stress, relative pathway gene expression regulation and phenotypic changes in cells. Excess heme plays a detrimental role in atherosclerosis, heart failure, myocardial ischemia-reperfusion injury, degenerative aortic valve stenosis, cardiac iron overload. Recent researches revealed that in some cases heme involved in cardiac damage though ferroptosis. Thus, heme concentrations beyond normal levels are dangerous. Further research on the role of heme in cardiovascular diseases is needed.

Multi-Sequence MRI Registration of Atherosclerotic Carotid Arteries Based on Cross-Scale Siamese Network

Cardiovascular disease (CVD) is a common disease with high mortality rate, and carotid atherosclerosis (CAS) is one of the leading causes of cardiovascular disease. Multisequence carotid MRI can not only identify carotid atherosclerotic plaque constituents with high sensitivity and specificity, but also obtain different morphological features, which can effectively help doctors improve the accuracy of diagnosis. However, it is difficult to evaluate the accurate evolution of local changes in carotid atherosclerosis in multi-sequence MRI due to the inconsistent parameters of different sequence images and the geometric space mismatch caused by the motion deviation of tissues and organs. To solve these problems, we propose a cross-scale multi-modal image registration method based on the Siamese U-Net. The network uses sub-networks with image inputs of different sizes to extract various features, and a special padding module is designed to make the network available for training on cross-scale features. In addition, to improve the registration performance, a multi-scale loss function under Gaussian smoothing is applied for optimization. For the experiments, we have collected a multi-sequence MRI image dataset from 11 patients with carotid atherosclerosis for a retrospective study. We evaluate our overall architectures by cross-validation on our carotid dataset. The experimental results show that our method can generate precise and reliable results with cross-scale multi-sequence inputs and the registration accuracy can be greatly improved by using the Gaussian smoothing loss function. The DSC of our Siamese structure can reach 84.1% on the carotid data set with cross-size input. With the use of GDSC loss, the average DSC can be improved by 5.23%, while the average distance between fixed landmarks and moving landmarks can be decreased by 6.46%.Our code is made publicly available at: https://github.com/MingHan98/Cross-scale-Siamese-Unet.

Immune system and atherosclerosis: Hostile or friendly relationship

Coronary artery disease has remained a major health challenge despite enormous progress in prevention, diagnosis, and treatment strategies. Formation of atherosclerotic plaque is a chronic process that is developmentally influenced by intrinsic and extrinsic determinants. Inflammation triggers atherosclerosis, and the fundamental element of inflammation is the immune system. The immune system involves in the atherosclerosis process by a variety of immune cells and a cocktail of mediators. It is believed that almost all main components of this system possess a profound contribution to the atherosclerosis. However, they play contradictory roles, either protective or progressive, in different stages of atherosclerosis progression. It is evident that monocytes are the first immune cells appeared in the atherosclerotic lesion. With the plaque growth, other types of the immune cells such as mast cells, and T lymphocytes are gradually involved. Each cell releases several cytokines which cause the recruitment of other immune cells to the lesion site. This is followed by affecting the expression of other cytokines as well as altering certain signaling pathways. All in all, a mix of intertwined interactions determine the final outcome in terms of mild or severe manifestations, either clinical or subclinical. Therefore, it is of utmost importance to precisely understand the kind and degree of contribution which is made by each immune component in order to stop the growing burden of cardiovascular morbidity and mortality. In this review, we present a comprehensive appraisal on the role of immune cells in the atherosclerosis initiation and development.

High lipoprotein(a) is associated with major adverse limb events after femoral artery endarterectomy

BACKGROUNDS AND AIMS

Elevated lipoprotein(a) (Lp[a]) has been identified as a causal risk factor for cardiovascular disease including peripheral arterial disease (PAD). Although Lp(a) is associated with the diagnosis of PAD, it remains elusive whether there is an association of Lp(a) with cardiovascular and limb events in patients with severe PAD.

METHODS

Preoperative plasma Lp(a) levels were measured in 384 consecutive patients that underwent iliofemoral endarterectomy and were included in the Athero-Express biobank. Our primary objective was to assess the association of Lp(a) levels with Major Adverse Limb Events (MALE). Our secondary objective was to relate Lp(a) levels to Major Adverse Cardiovascular Events (MACE) and femoral plaque composition that was acquired from baseline surgery.

RESULTS

During a median follow-up time of 5.6 years, a total of 225 MALE were recorded in 132 patients. Multivariable analysis, including history of peripheral intervention, age, diabetes mellitus, end stage renal disease and PAD disease stages, showed that Lp(a) was independently associated with first (HR of 1.36 (95% CI 1.02-1.82) p = .036) and recurrent MALE (HR 1.36 (95% CI 1.10-1.67) p = .004). A total of 99 MACE were recorded but Lp(a) levels were not associated with MACE.sLp(a) levels were significantly associated with a higher presence of smooth muscle cells in the femoral plaque, although this was not associated with MALE or MACE.

CONCLUSIONS

Plasma Lp(a) is independently associated with first and consecutive MALE after iliofemoral endarterectomy. Hence, in patients who undergo iliofemoral endarterectomy, Lp(a) could be considered as a biomarker to enhance risk stratification for future MALE.

Assessment of Therapeutic Response to Statin Therapy in Patients With Intracranial or Extracranial Carotid Atherosclerosis by Vessel Wall MRI: A Systematic Review and Updated Meta-Analysis

Background and Aims: Statin therapy is an essential component of cardiovascular preventive care. In recent years, various vessel wall MRI (VW-MRI) techniques have been used to monitor atherosclerosis progression or regression in patients with extracranial or intracranial large-artery atherosclerosis. We aimed to perform a systematic review and meta-analysis on the effects of statin therapy on plaque evolution as assessed by VW-MRI.

Materials and Methods: Prospective studies investigating carotid and intracranial atherosclerotic plaques in patients on statin therapy monitored by serial VW-MRI were systematically identified in the literature. The plaque burden and lipid-rich necrotic core (LRNC) volume of carotid plaque and the imaging features of intracranial plaques were extracted and summarized. For studies investigating carotid artery wall volume and LRNC volume, combined estimates were derived by meta-analysis.

Results: The study identified 21 studies of carotid plaque and two studies of intracranial plaque. While 16 studies investigating carotid plaques that included 780 patients by High-resolution VW-MRI were included in the meta-analysis. There was no significant change in carotid wall volume from baseline to 12 months. A significant change in LRNC volume was observed at > 12 months compared with baseline (Effect = −10.69, 95% CI = −19.11, −2.28, P < 0.01), while no significant change in LRNC volume at 3–6 months or 7–12 months after statin therapy initiation in 6 studies. Increases in fibrous tissue and calcium and reduction in neovascularization density of the plaque were seen in 2/3 studies (including 48/59 patients), 1/3 studies (including 17/54 patients), and 2/2 studies (including 71 patients) after statin therapy, respectively. Two studies with 257 patients in intracranial atherosclerosis showed that statins could effectively decrease wall volume and plaque enhancement volume.

Conclusions: Collective data indicated that statins could potentially stabilize carotid plaques by significantly reducing LRNC with 1 year of therapy as shown on serial carotid VW-MRI. There was no significant decrease in wall volume, which nonetheless indicated that plaque composition changes might be more sensitive to response monitoring than wall volume. It is likely that more sensitive, clinically relevant, and preferably quantitative indicators of therapeutic effects on intracranial vessel plaque morphology will be developed in the future.

Pre-Operative Plasma Extracellular Vesicle Proteins are Associated with a High Risk of Long Term Secondary Major Cardiovascular Events in Patients Undergoing Carotid Endarterectomy

OBJECTIVE

Patients undergoing carotid endarterectomy (CEA) maintain a substantial residual risk of major cardiovascular events (MACE). Improved risk stratification is warranted to select high risk patients qualifying for secondary add on therapy. Plasma extracellular vesicles (EVs) are involved in atherothrombotic processes and their content has been related to the presence and recurrence of cardiovascular events. The association between pre-operative levels of five cardiovascular disease related proteins in plasma EVs and the post-operative risk of MACE was assessed.

METHODS

In 864 patients undergoing CEA from 2002 to 2016 included in the Athero-Express biobank, three plasma EV subfractions (low density lipoprotein [LDL], high density lipoprotein [HDL], and tiny extracellular vesicles [TEX]) were isolated from pre-operative blood samples. Using an electrochemiluminescence immunoassay, five proteins were quantified in each EV subfraction: cystatin C, serpin C1, serpin G1, serpin F2, and CD14. The association between EV protein levels and the three year post-operative risk of MACE (any stroke, myocardial infarction, or cardiovascular death) was evaluated using multivariable Cox proportional hazard regression analyses.

RESULTS

During a median follow up of three years (interquartile range 2.2 - 3.0), 137 (16%) patients developed MACE. In the HDL-EV subfraction, increased levels of CD14, cystatin C, serpin F2, and serpin C1 were associated with an increased risk of MACE (adjusted hazard ratios per one standard deviation increase of 1.30, 95% confidence interval [CI] 1.15-1.48; 1.22, 95% CI 1.06-1.42; 1.36, 95% CI 1.16-1.61; and 1.29, 95% CI 1.10-1.51; respectively), independently of cardiovascular risk factors. No significant associations were found for serpin G1. CD14 improved the predictive value of the clinical model encompassing cardiovascular risk factors (net re-classification index = 0.16, 95% CI 0.08-0.21).

CONCLUSION

EV derived pre-operative plasma levels of cystatin C, serpin C1, CD14, and serpin F2 were independently associated with an increased long term risk of MACE after CEA and are thus markers for residual cardiovascular risk. EV derived CD14 levels could improve the identification of high risk patients who may benefit from secondary preventive add on therapy in order to reduce future risk of MACE.

Mast Cell Distribution in Human Carotid Atherosclerotic Plaque Differs Significantly by Histological Segment

OBJECTIVE

Mast cells (MCs) are important contributors to atherosclerotic plaque progression. For prospective studies on mast cell contributions to plaque instability, the distribution of intraplaque MCs needs to be elucidated. Plaque stability is generally histologically assessed by dividing the plaque specimen into segments to be scored on an ordinal scale. However, owing to competitive use, studies may have to deviate to adjacent segments, yet intersegment differences of plaque characteristics, especially MCs, are largely unknown. Therefore, the hypothesis that there is no segment to segment difference in MC distribution between atherosclerotic plaque segments was tested, and intersegment associations between MCs and other plaque characteristics was investigated.

METHODS

Twenty-six carotid atherosclerotic plaques from patients undergoing carotid endarterectomy included in the Athero-Express Biobank were analysed. The plaque was divided in 5 mm segments, differentiating between the culprit lesion (segment 0), adjacent segments (-1/+1) and more distant segments (-2/+2) for the presence of MCs. The associations between the intersegment distribution of MCs and smooth muscle cells, macrophage content, and microvessel density in the culprit lesion were studied.

RESULTS

A statistically significant difference in MCs/mm² between the different plaque segments (p < .001) was found, with a median of 2.79 (interquartile range [IQR] 1.63 - 7.10) for the culprit lesion, 1.34 (IQR 0.26 - 4.45) for the adjacent segment, and 0.62 (0.14 - 2.07) for the more distant segment. Post hoc analyses showed that intersegment differences were due to differences in MCs/mm² between the culprit and adjacent segment (p = .037) and between the culprit lesion and the more distant segment (p < .001). MCs/mm² in multiple different segments were positively correlated with microvessel density and macrophage content in the culprit lesion.

CONCLUSION

MC numbers reveal significant intersegment differences in human carotid plaques. Future histological studies on MCs should use a standardised segment for plaque characterisation as plaque segments cannot be used interchangeably for histological MC analyses.

The Role of Blood Pressure in Carotid Plaque Incidence: Interactions With Body Mass Index, Age, and Sex-Based on a 7-Years Cohort Study

Background: Although high blood pressure (BP) is a risk factor for carotid plaque, its long-term prognostic value might be underestimated due to its confounding interactions with BMI, age, and gender. Therefore, we conducted a 7-year prospective cohort study to evaluate the prognostic value of BP for the incidence of carotid plaque. Methods: The subjects enrolled in 2011 were free of carotid plaque at baseline and were followed up in 2018. Multivariate Cox proportional-hazards models were used to evaluate the association between BP and carotid plaque incidence. Results: During the follow-up study, the incidence of carotid plaque was 36.5%. The significant positive linear trend showed that subjects with higher BP levels at baseline were more likely to develop carotid plaques at the end. Especially in the female subpopulation, after confounders being adjusted, the carotid plaque was associated with higher BP (adjusted HR 1.52, 95% CI 1.02-2.26), pulse pressure (PP) (adjusted HR 1.15, 95% CI 0.76-1.75), and mean arterial pressure (MAP) (adjusted HR 1.44, 95% CI 1.00-2.08). The adjusted HRs of hypertension, PP, and MAP (HR 27.71, 95% CI 2.27-338.64; HR 14.47, 95% CI 1.53-137.18; HR 9.97, 95% CI 1.29-77.28) were significantly higher after the potential antagonistic interactions between BP categorical indicators and age being adjusted, respectively. Conclusion: High BP indicators might be associated with higher HRs of carotid plaque after adjusting interactions between BP indicators and BMI, age, and gender, which suggests that the incidence of carotid plaque in female adults with high BP indicators might increase significantly with the increase of age.

Correlation between serum uric acid levels and carotid plaque neovascularisation assessed by contrast-enhanced ultrasound

AIM

To investigate the potential impact of serum uric acid (SUA) levels on the grade of intraplaque neovascularisation (IPN) at contrast-enhanced ultrasound (CEUS).

MATERIAL AND METHODS

The study screened 212 patients with carotid atherosclerotic plaques using conventional ultrasound, and the patients then underwent CEUS. Based on the distribution of contrast medium microbubbles in the plaque, patients were split into three groups: 60 patients regarded as grade 0-1 (group A), 81 patients as grade 2 (group B), and 71 patients as grade 3 (group C), and SUA levels were measured on the second day after CEUS.

RESULTS

The frequencies of stroke were statistically different between the three groups (p<0.05). In grades 0, 1, 2, and 3, SUA levels ranged from 236.92 ± 72.75, 276.46 ± 67.31, 283.93 ± 53.85, and 384.49 ± 79.80 μmol/l, respectively. Spearman's analysis showed that the visual grade of IPN at CEUS correlated linearly with the SUA level (r=0.551, p<0.01). The difference in SUA levels between different sexes was statistically significant (p<0.05), and the differences in plaque echogenicity and diastolic blood pressure (DBP) between the three groups were also statistically significant (all p<0.05).

CONCLUSIONS

SUA levels correlate positively with the visual grade of IPN at CEUS, which may promote plaque vulnerability. The present results may further help to optimise therapy for vulnerable plaque and improve stroke risk stratification strategies.

Deep learning-based carotid plaque vulnerability classification with multicentre contrast-enhanced ultrasound video: a comparative diagnostic study

OBJECTIVES

The aim of this study was to evaluate the performance of deep learning-based detection and classification of carotid plaque (DL-DCCP) in carotid plaque contrast-enhanced ultrasound (CEUS).

METHODS AND ANALYSIS

A prospective multicentre study was conducted to assess vulnerability in patients with carotid plaque. Data from 547 potentially eligible patients were prospectively enrolled from 10 hospitals, and 205 patients with CEUS video were finally enrolled for analysis. The area under the receiver operating characteristic curve (AUC) was used to evaluate the effectiveness of DL-DCCP and two experienced radiologists who manually examined the CEUS video (RA-CEUS) in diagnosing and classifying carotid plaque vulnerability. To evaluate the influence of dynamic video input on the performance of the algorithm, a state-of-the-art deep convolutional neural network (CNN) model for static images (Xception) was compared with DL-DCCP for both training and holdout validation cohorts.

RESULTS

The AUCs of DL-DCCP were significantly better than those of the experienced radiologists for both the training and holdout validation cohorts (training, DL-DCCP vs RA-CEUS, AUC: 0.85 vs 0.69, p<0.01; holdout validation, DL-DCCP vs RA-CEUS, AUC: 0.87 vs 0.66, p<0.01), that is, also better than the best deep CNN model Xception we had performed, for both the training and holdout validation cohorts (training, DL-DCCP vs Xception, AUC:0.85 vs 0.82, p<0.01; holdout validation, DL-DCCP vs Xception, AUC: 0.87 vs 0.77, p<0.01).

CONCLUSION

DL-DCCP shows better overall performance in assessing the vulnerability of carotid atherosclerotic plaques than RA-CEUS. Moreover, with a more powerful network structure and better utilisation of video information, DL-DCCP provided greater diagnostic accuracy than a state-of-the-art static CNN model.

TRIAL REGISTRATION NUMBER

ChiCTR1900021846.

Preclinical carotid atherosclerosis as an indicator of polyvascular disease: a narrative review

Carotid atherosclerotic lesions are correlated with atherosclerotic deterioration of the arterial wall in other vascular territories and with cardiovascular events. The detection of pre-symptomatic carotid lesions like intima-media thickness (IMT) and asymptomatic carotid plaques is possible by non-invasive ultrasound duplex scanning. Current measurement guidelines suggest an average measurement of IMT within 10 mm of the segment of the common carotid artery. The thickening of intima-media appears in a long subclinical period of atherosclerosis. Therefore, the determination of IMT has emerged as one of the methods for determining early structural deterioration of the arterial wall. A close interrelationship was shown between IMT and risk factors of atherosclerosis, their duration, and intensity. Different studies demonstrated that increased IMT is a powerful predictor of coronary, cerebrovascular, and peripheral arterial occlusive disease and their complication. A recent meta-analysis indicated a minimal improvement in the risk estimation of cardiovascular events after adding IMT to the Framingham Risk Score. These findings influenced the latest ACC/AHA guidelines which again recommend the use of carotid IMT measurement for individual risk assessment. The presence of atherosclerotic plaques indicates that the atherosclerotic process is already ongoing. The findings of different studies are equivocal that carotid plaques independently predict cardiovascular events and improve risk predictions for coronary artery disease when added to the Framingham Risk Score. However, besides the size of plaque and grade of stenosis, the structure of plaque calcification, vascularization, lipid core, and the surface of plaques are important indicators of related risks for cardiovascular events.

Sclerostin Downregulation Globally by Naturally Occurring Genetic Variants, or Locally in Atherosclerotic Plaques, Does Not Associate With Cardiovascular Events in Humans

Inhibition of sclerostin increases bone formation and decreases bone resorption, leading to increased bone mass, bone mineral density, and bone strength and reduced fracture risk. In a clinical study of the sclerostin antibody romosozumab versus alendronate in postmenopausal women (ARCH), an imbalance in adjudicated serious cardiovascular (CV) adverse events driven by an increase in myocardial infarction (MI) and stroke was observed. To explore whether there was a potential mechanistic plausibility that sclerostin expression, or its inhibition, in atherosclerotic (AS) plaques may have contributed to this imbalance, sclerostin was immunostained in human plaques to determine whether it was detected in regions relevant to plaque stability in 94 carotid and 50 femoral AS plaques surgically collected from older female patients (mean age 69.6 ± 10.4 years). Sclerostin staining was absent in most plaques (67%), and when detected, it was of reduced intensity compared with normal aorta and was located in deeper regions of the plaque/wall but was not observed in areas considered relevant to plaque stability (fibrous cap and endothelium). Additionally, genetic variants associated with lifelong reduced sclerostin expression were explored for associations with phenotypes including those related to bone physiology and CV risk factors/events in a population-based phenomewide association study (PheWAS). Natural genetic modulation of sclerostin by variants with a significant positive effect on bone physiology showed no association with lifetime risk of MI or stroke. These data do not support a causal association between the presence of sclerostin, or its inhibition, in the vasculature and increased risk of serious cardiovascular events. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).