Sex Differences in Carotid Atherosclerosis: A Systematic Review and Meta-Analysis

Relationship Between Carotid Artery Remodeling Characteristics and Early Carotid Atherosclerosis: An Ultrasonographic Multicenter Study

OBJECTIVES

This study analyzed carotid artery remodeling characteristics in early carotid atherosclerosis (ECAS).

METHODS

The 1021 participants were evaluated using ultrasonography and categorized into three groups: Group A, 391 participants with increased intima-media thickness (IMT); Group B, 300 participants with atherosclerotic plaque only on the carotid bulb (CB); and the control group (330 participants). The ratios of the diameters in the CB to those in the common carotid artery (DCCA) and internal carotid artery (DICA) were defined as carotid index1 (CI1) and 2 (CI2).

RESULTS

Group A had a higher DCCA, DCB, and CI2 than the controls (P < .05). Group B had a smaller DCB, CI1, and CI2 than Group A, and higher DCCA and smaller CI1 than the controls (P < .05). Logistic regression showed that CI2 was a positive influencing factor for increased IMT (OR: 3.42, 95% CI: 1.74-6.70, P < .001), and CI1 was a negative independent factor for CB plaque formation (OR: 0.11, 95% CI: 0.04-0.28, P < .001). Multiple linear regression showed that only in Group B, the vessel side had a significant influence on CI1 (β = 0.055, P < .05), while age, sex, body mass index, and cerebrovascular risk factors had no significant correlation with CI.

CONCLUSIONS

The CB and common carotid artery showed positive remodeling with increased IMT, however, the CB showed negative remodeling with plaque formation. CI changes were consistent with CB remodeling. CI was an independent influencing factor for ECAS, and it was only affected by vessel side, providing an objective predictive parameter for ECAS.

Stroke risk management in carotid atherosclerotic disease: a clinical consensus statement of the ESC Council on Stroke and the ESC Working Group on Aorta and Peripheral Vascular Diseases

Carotid atherosclerotic disease continues to be an important cause of stroke, often disabling or fatal. Such strokes could be largely prevented through optimal medical therapy and carotid revascularization. Advancements in discovery research and imaging along with evidence from recent pharmacology and interventional clinical trials and registries and the progress in acute stroke management have markedly expanded the knowledge base for clinical decisions in carotid stenosis. Nevertheless, there is variability in carotid-related stroke prevention and management strategies across medical specialities. Optimal patient care can be achieved by (i) establishing a unified knowledge foundation and (ii) fostering multi-specialty collaborative guidelines. The emergent Neuro-Vascular Team concept, mirroring the multi-disciplinary Heart Team, embraces diverse specializations, tailors personalized, stratified medicine approaches to individual patient needs, and integrates innovative imaging and risk-assessment biomarkers. Proposed approach integrates collaboration of multiple specialists central to carotid artery stenosis management such as neurology, stroke medicine, cardiology, angiology, ophthalmology, vascular surgery, endovascular interventions, neuroradiology, and neurosurgery. Moreover, patient education regarding current treatment options, their risks and advantages, is pivotal, promoting patient's active role in clinical care decisions. This enables optimization of interventions ranging from lifestyle modification, carotid revascularization by stenting or endarterectomy, as well as pharmacological management including statins, novel lipid-lowering and antithrombotic strategies, and targeting inflammation and vascular dysfunction. This consensus document provides a harmonized multi-specialty approach to multi-morbidity prevention in carotid stenosis patients, based on comprehensive knowledge review, pinpointing research gaps in an evidence-based medicine approach. It aims to be a foundational tool for inter-disciplinary collaboration and prioritized patient-centric decision-making.

Carotid Plaque Calcification Attenuation Characteristics are Associated with Intraplaque Hemorrhage Volumes: A 3D Segmentation-Based Analysis

Background and Purpose

Despite the high prevalence of plaque calcifications in carotid atherosclerosis, the association between morphologic and attenuation features of calcifications and intraplaque hemorrhage (IPH) remains unclear.

Methods

Carotid bifurcation calcific plaques were identified on neck CTAs from patients with unilateral anterior circulation ischemic stroke consistent with embolic stroke of undetermined source. Plaque calcifications were manually segmented using 3D Slicer to measure volume, surface area, shape, and attenuation (Hounsfield Units (HU)) characteristics. IPH volume (IPHvol) was quantified using a semi-automated software. A linear mixed regression model evaluated associations between calcification features and IPHvol, adjusting for sex, age, and cardiovascular risk factors. An interaction term between calcification volume and attenuation was included after dichotomizing attenuation (>924HU) and volume (>30mm 3 ) as high versus low based on median values.

Results

From 70 patients (median age 68 years, 50% female), 116 calcific plaques containing 269 plaque calcifications were analyzed. Adjusting for age, cardiovascular risk factors and plaque calcification features, being female showed lower IPHvols compared to males (mean ratio 0.34, p=0.002). A significant interaction between calcification volume and attenuation emerged (p=0.042). Among plaques with low volumes (<30mm 3 ) of plaque calcifications, plaques with low-attenuation (<924HU) calcifications showed 5.53 times higher IPHvols than plaques with high-attenuation calcifications (p=0.003). Among plaques with high-attenuation calcifications (>924HU), plaques with high volumes of these calcifications showed 4.40 times higher IPHvols compared to low-volumes of high-attenuation calcifications (p=0.011).

Conclusions

Plaque calcification attenuation characteristics are associated with IPHvols. Beyond presence or volumes of plaque calcifications, calcification attenuation characteristics should be considered when evaluating unstable plaque components.

Sex Differences in Peripheral Vascular Disease: A Scientific Statement From the American Heart Association

Sex differences in the risk factors, diagnosis, treatment, and outcomes of patients with cardiovascular disease have been well described; however, the bulk of the literature has focused on heart disease in women. Data on sex differences in peripheral vascular disease are ill defined, and there is a need to report and understand those sex-related differences to mitigate adverse outcomes related to those disparities. Although peripheral vascular disease is a highly diverse group of disorders affecting the arteries, veins, and lymphatics, this scientific statement focuses on disorders affecting the peripheral arteries to include the aorta and its branch vessels. The purpose of this scientific statement is to report the current status of sex-based differences and disparities in peripheral vascular disease and to provide research priorities to achieve health equity for women with peripheral vascular disease.

Biomechanical assessment of vulnerable plaque: from histological evidence to ultrasound elastography and image-based computational patient-specific modelling

The assessment of carotid plaque vulnerability is a relevant clinical information that can help prevent adverse cerebrovascular events. To this aim, in this work we study the ability of different non-invasive methods for assessing plaque vulnerability in patients undergoing carotid endarterectomy (CEA). Histological examinations of patients' plaque samples were conducted after CEA while ultrasound (US) and computed tomography angiography (CTA) acquisitions were performed preoperatively. US acquisition included point shear wave elastography (p-SWE) and a radio frequency echo-based wall tracking mode for the evaluation of arterial wall stiffness. CTA images were segmented, and the results were used for an ad hoc procedure that semi-automatically reconstructed the atherosclerotic wall providing a 3D model of the different plaque components to perform patient-specific finite element analysis (FEA) of stress distributions. One hundred patients were involved in the study and a macroscopic assessment of the surgeon was used to classify carotid atherosclerotic plaques as vulnerable or stable. The data derived from histological analysis, US acquisitions and FEA were correlated with the outcome of the classification. Indeed, histological features differentiated between vulnerable and stable plaques, confirming the surgeon's classification. From p-SWE, the measurement of Young's Modulus (YM) in stable plaques was significantly higher than in vulnerable plaques. Also stress indexes related to the Von Mises and Max Principal stresses from FEAs showed statistically significant differences between plaque groups. These results demonstrate that both stiffness-related US measurements and stress parameters derived preoperatively from computational analyses were able to differentiate patients with vulnerable plaques from ones with stable plaques. Thus, the development and application of new methods for a non-invasive biomechanical assessment of atherosclerotic artery walls could give valuable information for plaque vulnerability evaluation.

Sex differences in age-associated neurological diseases-A roadmap for reliable and high-yield research

Once taken into consideration, sex differences in neurological diseases emerge in abundance: (i) Stroke severity is significantly higher in females than in males, (ii) Alzheimer's disease (AD) pathology is more pronounced in females, and (iii) conspicuous links with hormonal cycles led to female-specific diagnoses, such as catamenial migraines and epilepsy. While these differences receive increasing attention in isolation, they likely link to similar processes in the brain. Hence, this review aims to present an overview of the influences of sex chromosomes, hormones, and aging on male and female brains across health and disease, with a particular focus on AD and stroke. The focus here on advancements across several fields holds promise to fuel future research and to lead to an enriched understanding of the brain and more effective personalized neurologic care for all.

Temporal trends and disparities in atherosclerosis-associated cerebrovascular disease mortality in the United States, 1999-2020

BACKGROUND

Cerebrovascular disease (CEVD) accounts for the second leading cause of death worldwide. Despite recent advancements in treatment strategies, the prevalence and cost associated with CEVD are rising. Atherosclerosis significantly contributes to CEVD risk by restricting cerebral blood flow, leading to ischemic stroke. This study aims to analyze trends in atherosclerosis-associated CEVD mortality in the United States from 1999 to 2020 to inform targeted prevention and management strategies.

METHODS

We examined death certificates sourced from the CDC WONDER database, from 1999 to 2020 to identify atherosclerosis-associated CEVD mortality. Age-adjusted mortality rates (AAMRs) per 100,000 persons and annual percent changes were reported.

RESULTS

A total of 325,401 deaths occurred from CEVD among adults with atherosclerosis from 1999 to 2020 in the US. The overall AAMR initially inclined from 10.9 in 1999 to 12.6 in 2001, followed by a decrease to 4.2 in 2016, and then a rise till 2020 was observed. Males had consistently higher AAMRs than females throughout the study period (Men = 11.9 vs Women = 10.1). When stratified by race, AAMRs were highest among non-Hispanic (NH) Whites (6.9), followed by NH American Indian/Alaska Native (10.9), NH Blacks/African Americans (6.6), Hispanics (4.9), and lastly by Asian/Pacific Islanders (4.2). The Western region had the highest mortality (AAMR: 7.7).

CONCLUSION

The CEVD mortality rates of adults with atherosclerosis- are increasing in the adult U.S.

POPULATION

This underscores the need for increased screening, aggressive management, and subsequent surveillance of patients at risk.

Carotid plaque offsets sex-related differences in cardiovascular risk of young hypertensive patients

BACKGROUND

Women have a lower risk for cardiovascular (CV) disease compared to men. Whether this difference is influenced by the presence of hypertension-mediated organ damage is unknown.

OBJECTIVE

To assess whether the presence of carotid plaque (CP) impacts the sex difference in risk for CV events in treated hypertensive patients.

METHODS

From the Campania Salute Network Registry 2419 women and men <51 years of age with treated hypertension and free from prevalent CV disease were included. The presence of CP was identified by Doppler ultrasound (intima-media thickness≥1.5 mm). The primary outcome was a composite of fatal and non-fatal stroke or myocardial infarction, sudden death, TIA, myocardial revascularization, de novo angina, and atrial fibrillation.

RESULTS

Among patients without CP at baseline (n = 1807), women were older, with higher systolic blood pressure, serum cholesterol level and prevalence of LVH but lower serum triglycerides and eGFR, compared to men (all p < 0.001). Among patients with CP (n = 612), women were older, used higher number of antihypertensive drugs, had higher serum cholesterol level and prevalence of left ventricular hypertrophy (LVH), but had lower serum triglycerides and eGFR compared to men (all p < 0.001). During follow-up, women without CP had a lower risk for CV disease than men (hazard ratio, HR, 0.51, 95 % confidence intervals, CI, 0.27-0.99, p = 0.04) after accounting for cardiovascular risk factors, LVH, and antihypertensive treatment. In contrast, among patients with CP, women had similar risk for CV disease compared with men (HR 1.3, 95 % CI, 0.59-2.9, p = 0.48).

CONCLUSIONS

Our findings suggest that the presence of CP in young patients with treated hypertension offsets the CV disease protection in women.

TRIAL REGISTRATION

NCT02211365.

Mendelian randomization studies of lifestyle-related risk factors for stroke: a systematic review and meta-analysis

Objective

Stroke risk factors often exert long-term effects, and Mendelian randomization (MR) offers significant advantages over traditional observational studies in evaluating the causal impact of these factors on stroke. This study aims to consolidate and evaluate the relationships between potential causal factors and stroke risk, drawing upon existing MR research.

Methods

A comprehensive search for MR studies related to stroke was conducted up to August 2023 using databases such as PubMed, Web of Science, Embase, and Scopus. This meta-analysis examines the relationships between potential causative factors and stroke risk. Both random-effects and fixed-effects models were utilized to compile the dominance ratios of various causative elements linked to stroke. The reliability of the included studies was assessed according to the Strengthening the Reporting of Observational Studies in Epidemiology incorporating Mendelian Randomization (STROBE-MR) guidelines.

Results

The analysis identified several risk factors for stroke, including obesity, hypertension, low-density lipoprotein cholesterol (LDL-C), chronic kidney disease (CKD), and smoking. Protective factors included high-density lipoprotein cholesterol (HDL-C), estimated glomerular filtration rate (eGFR), and educational attainment. Subgroup analysis revealed that type 2 diabetes mellitus (T2DM), diastolic blood pressure (DBP) are risk factors for ischemic stroke (IS).

Conclusion

This study confirms that variables such as obesity, hypertension, elevated LDL-C levels, CKD, and smoking are significantly linked to the development of stroke. Our findings provide new insights into genetic susceptibility and potential biological pathways involved in stroke development.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO, identifier CRD42024503049.

Prolonged Time-to-antihypertensive Therapy Worsens Organ Damage and Blood Pressure Control in Arterial Hypertension

INTRODUCTION

Delay in arterial hypertension (AH) diagnosis and late therapy initiation may affect progression towards hypertensive-mediated organ damage (HMOD) and blood pressure (BP) control.

AIM

We aimed to assess the impact of time-to-therapy on BP control and HMOD in patients receiving AH diagnosis.

METHODS

We analysed data from the Campania Salute Network, a prospective registry of hypertensive patients (NCT02211365). At baseline visit, time-to-therapy was defined as the interval between the first occurrence of BP values exceeding guidelines-directed thresholds and therapy initiation; HMOD included left ventricular hypertrophy (LVH), carotid plaque, or chronic kidney disease. Optimal BP control was considered for average values < 140/90 mmHg. Low-risk profile was defined as grade I AH without additional cardiovascular risk factors.

RESULTS

From 14,161 hypertensive patients, we selected 1,627 participants who were not on antihypertensive therapy. This population was divided into two groups based on the median time-to-therapy (≤ 2 years n = 1,009, > 2 years n = 618). Patients with a time-to-therapy > 2 years had higher risk of HMOD (adjusted odds ratio, aOR:1.51, 95%, CI:1.19-1.93, p < 0.001) due to increased risks of LVH (aOR:1.43, CI:1.12-1.82, p = 0.004), carotid plaques (aOR:1.29, CI:1.00-1.65, p = 0.047), and chronic kidney disease (aOR:1.68, CI:1.08-2.62, p = 0.022). Time-to-therapy > 2 years was significantly associated with uncontrolled BP values (aOR:1.49, CI:1.18-1.88, p < 0.001) and higher number of antihypertensive drugs (aOR:1.68, CI:1.36-2.08, p < 0.001) during follow-up. In low-risk subgroup, time-to-therapy > 2 years did not impact on BP control and number of drugs.

CONCLUSIONS

In hypertensive patients, a time-to-therapy > 2 years is associated with HMOD and uncontrolled BP.

Analysis of risk factors for carotid artery plaque in asymptomatic adults

OBJECTIVE

This study aimed to investigate the risk factors affecting the presence of carotid plaque in asymptomatic adults.

METHODS

Asymptomatic adults (age > 40 years, no symptoms of cardiovascular and cerebrovascular diseases) undergoing routine health examinations from physical examination department were included in this study. Carotid plaque was measured by Resona 7OB and Resona 8EXP color Doppler ultrasound and L9-3U and L4-5WU probes. The focal carotid intima-media thickness was greater than 1.1 mm, and the local protrusion of the artery wall into the artery lumen suggested the presence of carotid atherosclerotic plaque. According to their ultrasound results, 1077 asymptomatic adults were divided into a group with carotid plaque (477) and a group without carotid plaque (600).

RESULTS

A total of 1077 asymptomatic adults were included in this study, of whom 44.3% had carotid plaque. The proportion of men with carotid plaque was 84.5%. Multifactorial logistic analysis suggested that age, fasting blood glucose (FBG), total cholesterol (TC), homocysteine (Hcy) and male gender were risk factors for carotid atherosclerosis. The predictive probability of these risk factor indicators derived from the multifactorial model was calculated using receiver operating characteristic (ROC) curves with SPSS 25.0 software. The calculated area under the receiver operating characteristic curve (AUC) was 0.715 (95% CI, 0.685-0.746).

CONCLUSION

Age, FBG, TC, Hcy and male gender are risk factors for carotid atherosclerosis in asymptomatic adults. Gender differences in carotid atherosclerosis deserve further attention.

A Nationwide Analysis in France on Sex Difference and Outcomes Following Carotid Intervention in Asymptomatic Patients

Objective: The impact of sex on outcomes following carotid endarterectomy (CEA) and carotid artery stenting (CAS) is not fully elucidated. The aim of this study was to analyze the association between sex and outcomes of asymptomatic patients who underwent primary carotid interventions in France. Methods: This nationwide retrospective study was performed using the French National Health Insurance Information System and included asymptomatic patients who underwent primary carotid intervention over a 10-year period (1 January 2013 to 31 August 2023). Symptomatic patients and patients who had peri-operative neurologic events were excluded. The primary endpoints were the occurrence of death and stroke/transient ischaemic attack (TIA) at 30 days, 1 and 5 years after patients' discharge. Results: In total, 115,879 patients were admitted for an index CEA (29.4% women) and 6500 for CAS (29.8% women). In the CEA group, no significant sex-related difference was observed for 30-day mortality; however, women had significantly lower 1-year and 5-year mortality rates compared to men (1.9% vs. 2.6%, p < 0.001 and 7.9% vs. 11.1%, p < 0.001). In the CAS group, women had lower 30-day, 1-year and 5-year mortality (0.6% vs. 1.0%, p = 0.040, 3.8% vs. 4.9%, p = 0.048, and 10.4% vs. 15.0%, p < 0.001). A multivariate analysis showed that sex was not associated with the risk of stroke/TIA and mortality at 30 days (OR 0.84 (95% CI 0.67-1.04) and 1.27 (95% CI 0.98-1.64)). Male sex was associated with a higher risk of 1-year and 5-year mortality (OR 1.24 (95% CI 1.13-1.36) and 1.25 (95% CI 1.18-1.31)), but a lower risk of stroke/TIA than female sex. Conclusions: No significant sex-related difference was observed at 30 days in patients being discharged alive and without peri-operative neurologic events. Male sex was associated with a higher risk of mortality but a lower risk of stroke/TIA at 1 and 5 years.

Race, Ethnicity, and Gender Disparities in the Management and Outcomes of Critically Ill Adults with Acute Stroke

Racial, ethnicity and sex disparities are pervasive in the evaluation and acute care of ischemic stroke patients. Administration of intravenous thrombolysis and mechanical thrombectomy are the most critical steps in ischemic stroke treatment but compared to White patients, ischemic stroke patients from minority racial and ethnic groups are less likely to receive these potentially life-saving interventions. Sex and racial disparities in intracerebral hemorrhage or subarachnoid hemorrhage treatment have not been well studied.

Sex-related differences in coronary and carotid vessel geometry, plaque composition and shear stress obtained from imaging

Atherosclerosis manifests itself differently in men and women with respect to plaque initiation, progression and plaque composition. The observed delay in plaque progression in women is thought to be related to the hormonal status of women. Also features associated with the vulnerability of plaques to rupture seem to be less frequently present in women compared to men. Current invasive and non-invasive imaging modalities allow for visualization of plaque size, composition and high risk vulnerable plaque features. Moreover, image based modeling gives access to local shear stress and shear stress-related plaque growth. In this review, current knowledge on sex-related differences in plaque size, composition, high risk plaque features and shear stress related plaque growth in carotid and coronary arteries obtained from imaging are summarized.

Lipoprotein Metabolism, Dyslipidemia, and Lipid-Lowering Therapy in Women: A Comprehensive Review

Lipid-lowering therapy (LLT) is a cornerstone of atherosclerotic cardiovascular disease prevention. Although LLT might lead to different reductions in low-density lipoprotein cholesterol (LDL-C) levels in women and men, LLT diminishes cardiovascular risk equally effectively in both sexes. Despite similar LLT efficacy, the use of high-intensity statins, ezetimibe, and proprotein convertase subtilisin/kexin type 9 inhibitors is lower in women compared to men. Women achieve the guideline-recommended LDL-C levels less often than men. Greater cholesterol burden is particularly prominent in women with familial hypercholesterolemia. In clinical practice, women and men with dyslipidemia present with different cardiovascular risk profiles and disease manifestations. The concentrations of LDL-C, lipoprotein(a), and other blood lipids differ between women and men over a lifetime. Dissimilar levels of LLT target molecules partially result from sex-specific hormonal and genetic determinants of lipoprotein metabolism. Hence, to evaluate a potential need for sex-specific LLT, this comprehensive review (i) describes the impact of sex on lipoprotein metabolism and lipid profile, (ii) highlights sex differences in cardiovascular risk among patients with dyslipidemia, (iii) presents recent, up-to-date clinical trial and real-world data on LLT efficacy and safety in women, and (iv) discusses the diverse medical needs of women and men with dyslipidemia and increased cardiovascular risk.

Sex differences in outcomes of carotid artery stenting

OBJECTIVE

Existing evidence is inconclusive on whether women after carotid artery stenting (CAS) experience worse outcomes than men.

METHODS

The outcomes of women and men were compared using the data from nationwide retrospective registry between 2015 and 2019. The primary outcome was the incidence of ischemic stroke and all-cause death. Secondary outcomes included the incidence of ischemic stroke, all-cause death, acute occlusion, and acute myocardial infarction. Functional outcomes were the achieving an mRS score of 0-1 and 0-2. Outcomes were assessed at 30 days after CAS.

RESULTS

In total, 9792 patients (1330 women, 8862 men; mean age, 73.8 vs 73.5 years, p = 0.17) were analyzed. Symptomatic stenosis was common in men (52.0% vs. 55.1%; p = 0.03), while ≥50% stenosis after CAS was common in women (3.2% vs. 2.0%; p = 0.005). The primary outcome was no significantly difference in women and men (2.0% vs. 1.9%; adjusted odds ratio [aOR], 1.19; 95% confidence interval [95%CI], 0.75-1.88).The incidence of all-cause death was higher in women (0.9% vs. 0.5%; aOR, 2.45; 95%CI, 1.11-5.39). Functional outcomes were significantly less common in women than in men (mRS0-1, 72.6% vs. 74.8%; aOR, 0.77; 95%CI, 0.63-0.95; mRS0-2, 82.1% vs. 85.6%; aOR, 0.76; 95%CI, 0.60-0.95).

CONCLUSIONS

This study suggests that there was no significant sex differences in the incidence of ischemic stroke and all-cause death at 30 days. However, women have higher rate of all-cause death and poorer functional outcomes at 30 days than men.

Machine Learning Detects Symptomatic Plaques in Patients With Carotid Atherosclerosis on CT Angiography

BACKGROUND

This study aimed to develop and validate a computed tomography angiography based machine learning model that uses plaque composition data and degree of carotid stenosis to detect symptomatic carotid plaques in patients with carotid atherosclerosis.

METHODS

The machine learning based model was trained using degree of stenosis and the volumes of 13 computed tomography angiography derived intracarotid plaque subcomponents (eg, lipid, intraplaque hemorrhage, calcium) to identify plaques associated with cerebrovascular events. The model was internally validated through repeated 10-fold cross-validation and tested on a dedicated testing cohort according to discrimination and calibration.

RESULTS

This retrospective, single-center study evaluated computed tomography angiography scans of 268 patients with both symptomatic and asymptomatic carotid atherosclerosis (163 for the derivation set and 106 for the testing set) performed between March 2013 and October 2019. The area-under-receiver-operating characteristics curve by machine learning on the testing cohort (0.89) was significantly higher than the areas under the curve of traditional logit analysis based on the degree of stenosis (0.51, P<0.001), presence of intraplaque hemorrhage (0.69, P<0.001), and plaque composition (0.78, P<0.001), respectively. Comparable performance was obtained on internal validation. The identified plaque components and associated cutoff values that were significantly associated with a higher likelihood of symptomatic status after adjustment were the ratio of intraplaque hemorrhage to lipid volume (≥50%, 38.5 [10.1-205.1]; odds ratio, 95% CI) and percentage of intraplaque hemorrhage volume (≥10%, 18.5 [5.7-69.4]; odds ratio, 95% CI).

CONCLUSIONS

This study presented an interpretable machine learning model that accurately identifies symptomatic carotid plaques using computed tomography angiography derived plaque composition features, aiding clinical decision-making.

Machine Learning Modeling to Predict Atrial Fibrillation Detection in Embolic Stroke of Undetermined Source Patients

BACKGROUND

In patients with embolic stroke of undetermined source (ESUS), occult atrial fibrillation (AF) has been implicated as a key source of cardioembolism. However, only a minority acquire implantable cardiac loop recorders (ILRs) to detect occult paroxysmal AF, partly due to financial cost and procedural inconvenience. Without the initiation of appropriate anticoagulation, these patients are at risk of increased ischemic stroke recurrence. Hence, cost-effective and accurate methods of predicting AF in ESUS patients are highly sought after.

OBJECTIVE

We aimed to incorporate clinical and echocardiography data into machine learning (ML) algorithms for AF prediction on ILRs in ESUS.

METHODS

This was a single-center cohort study that included 157 consecutive patients diagnosed with ESUS from October 2014 to October 2017 who had ILR evaluation. We developed four ML models, with hyperparameters tuned, to predict AF detection on an ILR.

RESULTS

The median age of the cohort was 67 (IQR 59-74) years old and the median monitoring duration was 1051 (IQR 478-1287) days. Of the 157 patients, 32 (20.4%) had occult AF detected on the ILR. Support vector machine predicted for AF with a 95% confidence interval area under the receiver operating characteristic curve (AUC) of 0.736-0.737, multilayer perceptron with an AUC of 0.697-0.708, XGBoost with an AUC of 0.697-0.697, and random forest with an AUC of 0.663-0.674. ML feature importance found that age, HDL-C, and admitting heart rate were important non-echocardiography variables, while peak mitral A-wave velocity and left atrial volume were important echocardiography parameters aiding this prediction.

CONCLUSION

Machine learning modeling incorporating clinical and echocardiographic variables predicted AF in ESUS patients with moderate accuracy.

Improving radiomic modeling for the identification of symptomatic carotid atherosclerotic plaques using deep learning-based 3D super-resolution CT angiography

Rationale and objectives

Radiomic models based on normal-resolution (NR) computed tomography angiography (CTA) images can fail to distinguish between symptomatic and asymptomatic carotid atherosclerotic plaques. This study aimed to explore the effectiveness of a deep learning-based three-dimensional super-resolution (SR) CTA radiomic model for improved identification of symptomatic carotid atherosclerotic plaques.

Materials and methods

A total of 193 patients with carotid atherosclerotic plaques were retrospectively enrolled and allocated into either a symptomatic (n = 123) or an asymptomatic (n = 70) groups. SR CTA images were derived from NR CTA images using deep learning-based three-dimensional SR technology. Handcrafted radiomic features were extracted from both the SR and NR CTA images and three risk models were developed based on manually measured quantitative CTA characteristics and NR and SR radiomic features. Model performances were assessed via receiver operating characteristic, calibration, and decision curve analyses.

Results

The SR model exhibited the optimal performance (area under the curve [AUC] 0.820, accuracy 0.802, sensitivity 0.854, F1 score 0.847) in the testing cohort, outperforming the other two models. The calibration curve analyses and Hosmer-Lemeshow test demonstrated that the SR model exhibited the best goodness of fit, and decision curve analysis revealed that SR model had the highest clinical value and potential patient benefits.

Conclusions

Deep learning-based three-dimensional SR technology could improve the CTA-based radiomic models in identifying symptomatic carotid plaques, potentially providing more accurate and valuable information to guide clinical decision-making to reduce the risk of ischemic stroke.

Characterization of Atherosclerotic Mice Reveals a Sex-Dependent Susceptibility to Plaque Calcification but No Major Changes in the Lymphatics in the Arterial Wall

Lymphatics participate in reverse cholesterol transport, and their presence in the arterial wall of the great vessels and prior experimental results suggest their possible role in the development of atherosclerosis. The aim of this study was to characterize the lymphatic vasculature of the arterial wall in atherosclerosis. Tissue sections and tissue-cleared aortas of wild-type mice unveiled significant differences in the density of the arterial lymphatic network throughout the arterial tree. Male and female Ldlr-/- and ApoE-/- mice on a Western diet showed sex-dependent differences in plaque formation and calcification. Female mice on a Western diet developed more calcification of atherosclerotic plaques than males. The lymphatic vessels within the aortic wall of these mice showed no major changes regarding the number of lymphatic junctions and end points or the lymphatic area. However, female mice on a Western diet showed moderate dilation of lymphatic vessels in the abdominal aorta and exhibited indications of increased peripheral lymphatic function, findings that require further studies to understand the role of lymphatics in the arterial wall during the development of atherosclerosis.

Fibrinogen/albumin ratio and carotid artery plaques in coronary heart disease patients with different glucose metabolic states: a RCSCD-TCM study

AIM

The relationship between fibrinogen/albumin ratio (FAR) and carotid artery plaques (CAPs) was investigated in patients with coronary heart disease (CHD).

METHODS

A total of 11,624 patients with CHD were enrolled and divided into quartiles based on the FAR (Q1: FAR index ≤ 0.0663; Q2: 0.0664 ≤ FAR index ≤ 0.0790; Q3: 0.0791 ≤ FAR index ≤ 0.0944; Q4: FAR index > 0.0944). Patients were classified into three groups according to their blood glucose levels: normal glucose regulation (NGR), prediabetes mellitus (pre-DM), and diabetes mellitus (DM) groups. Carotid ultrasonography was performed to detect CAPs. The relationship between FAR and CAPs was evaluated using logistic and subgroup analyses.

RESULTS

Among 11,624 participants, 8738 (75.14%) had CAPs. Compared with Q1, the odds ratio (OR) of Q4 in patients with CHD was 2.00 (95% confidence interval [CI]: 1.71-2.34) after multivariate adjustment. Taking Q1 as a reference, a higher OR was observed in Q4 of FAR for CAPs in men [OR: 2.26; 95% CI: 1.73-2.95] in the multi-adjusted models. Moreover, multivariate adjustment indicated that the highest OR was observed in patients with CHD and DM (OR: 2.36; 95% CI: 1.80-3.10).

CONCLUSIONS

A significant association between FAR and CAPs was observed in patients with CHD, regardless of sex or blood glucose levels. Therefore, FAR may be used as an effective indicator to identify patients at a high risk of CAPs among patients with CHD.

Ophthalmic artery stenosis on three-dimensional rotational angiography: Interrater agreement, prevalence, and risk factors

BACKGROUND

There is emerging interest in ophthalmic artery (OA) stenosis angioplasty for the treatment of age-related macular degeneration. Three-dimensional rotational angiography (3DRA) could be used during conventional angiography to determine the presence and severity of OA stenosis. In patients who had undergone 3DRA of the internal carotid artery, we aimed to assess the interrater agreement, prevalence, and risk factors for OA stenosis.

METHODS

Consecutive patients from two centers who had undergone conventional angiography with 3DRA of the internal carotid arteries were enrolled in this study. 3DRAs were independently double read for the presence of OA stenosis, as defined as narrowing of the proximal OA of at least 50% when compared to the more distal "normal" OA. Interrater agreement for the evaluation of OA stenosis was assessed with the Cohen's kappa coefficient. Univariate and multivariable logistic regression were used to identify potential predictors of OA stenosis.

RESULTS

Three hundred and two patients (97 men; mean ± SD 57.6 ± 13.4 years) were included in the analysis. Cohen's kappa coefficient (95% CI) was 0.877 (0.798-0.956). OA stenosis was present in 45 patients (14.9%). Multiple logistic regression demonstrated that female sex (odds ratio [OR] = 2.70, 95% confidence interval [CI] 1.18-6.09, p = 0.02) and smoking (OR = 2.11, 95% CI 1.10-4.06, p = 0.03) were significant risk factors for OA stenosis. Age, hypertension, diabetes, coronary artery disease, and subarachnoid hemorrhage were not associated with OA stenosis.

CONCLUSION

The evaluation of OA stenosis on 3DRA had excellent interrater agreement. OA stenosis was common and was associated with smoking and female sex.

Macrophage profiling in atherosclerosis: understanding the unstable plaque

The development and rupture of atherosclerotic plaques is a major contributor to myocardial infarctions and ischemic strokes. The dynamic evolution of the plaque is largely attributed to monocyte/macrophage functions, which respond to various stimuli in the plaque microenvironment. To this end, macrophages play a central role in atherosclerotic lesions through the uptake of oxidized low-density lipoprotein that gets trapped in the artery wall, and the induction of an inflammatory response that can differentially affect the stability of the plaque in men and women. In this environment, macrophages can polarize towards pro-inflammatory M1 or anti-inflammatory M2 phenotypes, which represent the extremes of the polarization spectrum that include Mhem, M(Hb), Mox, and M4 populations. However, this traditional macrophage model paradigm has been redefined to include numerous immune and nonimmune cell clusters based on in-depth unbiased single-cell approaches. The goal of this review is to highlight (1) the phenotypic and functional properties of monocyte subsets in the circulation, and macrophage populations in atherosclerotic plaques, as well as their contribution towards stable or unstable phenotypes in men and women, and (2) single-cell RNA sequencing studies that have advanced our knowledge of immune, particularly macrophage signatures present in the atherosclerotic niche. We discuss the importance of performing high-dimensional approaches to facilitate the development of novel sex-specific immunotherapies that aim to reduce the risk of cardiovascular events.

Risk Factors for Medial and Intimal Intracranial Internal Carotid Artery Calcification in Men and Women with Cardiovascular Disease: The UCC-SMART Study

INTRODUCTION

Calcifications of the intracranial internal carotid artery (iICA) can lead to an increased risk for stroke. Two types of iICA calcification are known: those affecting the tunica intima or the tunica media. In extracranial arteries, risk factors and calcification patterns are different in women and men, but little is known regarding the iICA. In this study, we aimed to identify sex-specific risk profiles and medications associated to intimal and medial iICA calcification in patients with cardiovascular disease (CVD).

METHODS

Participants of the UCC-SMART cohort undergoing a non-contrast head CT within 6 months from the study inclusion were considered (n = 475). Intimal or medial iICA calcification pattern was assessed using a previously histology-validated method. Sex-stratified associations between calcification pattern and cardiovascular risk factors, laboratory parameters, and medication use were calculated using Poisson regression analysis with robust standard errors.

RESULTS

Two hundred and four women and 271 men (age range 24-79 years) were included. 45.4% of men and 34.8% of women showed intimal iICA calcification, while 28.4% of men and 24.0% of women showed medial iICA calcification. Minimal or no iICA calcification was observed in 26.2% of men and in 41.2% of women (reference group). Older age was associated with both calcification patterns in women and men. In women, use of vitamin K antagonists and lipid-lowering drugs was associated to medial calcification, while systolic blood pressure and glucose levels were associated to intimal calcification. In men, current smoking was associated to intimal calcification.

CONCLUSIONS

Women and men with CVD show differences in risk profiles and medication use associated to intimal and medial iCA calcification.

Sex-based differences in ischemic cardiovascular and bleeding outcomes following implantation of drug-eluting stent in patients at high bleeding risk

BACKGROUND

Patients with high bleeding risk (HBR) may exhibit uncertain adherence to dual antiplatelet therapy (DAPT) following drug-eluting stent (DES) implantation. The current population-based cohort study aimed to investigate the sex-based differences in adverse outcomes among the HBR population by analyzing the National Health Insurance Research Database in Taiwan.

METHODS

Patients who had HBR features defined by the Academic Research Consortium (ARC) and received DES implantation between January 1, 2007, and December 31, 2017, were enrolled. Propensity score matching was adopted to select 3,981 pairs with similar clinical cardiovascular risks but different sexes. A competing risk model was performed to evaluate the risk of adverse ischemic events (cardiac death, nonfatal myocardial infarction, and ischemic stroke) and any bleeding events in both sexes. Noncardiac death was considered a competing risk.

RESULTS

Within a 5-year follow-up, the incidence rates (per 1,000 person-year (95% confidence interval (CI)) of composite ischemic events and any bleeding events in males were respectively 44.09 (40.25-48.30) and 42.55 (38.79-46.68), while those in females were respectively 40.18 (36.51-44.23) and 42.35 (38.57-46.51). After adjustment for clinical variables, male patients had a marginally increased risk in the composite ischemic events (adjusted subdistribution hazard ratio (SHR) = 1.15 (1.00-1.31), p = 0.045) and a similar risk of any bleeding events (adjusted SHR = 1.00 (0.88-1.15), p = 0.946) compared with female patients.

CONCLUSIONS

Of the HBR population, males had an increased risk of ischemic outcomes but a similar risk of bleeding compared with females following DES implantation.

Sex Associations Between Air Pollution and Estimated Atherosclerotic Cardiovascular Disease Risk Determination

Objective: The purpose of this study was to investigate the sex correlations of particulate matters (PM2.5, PM10, PM2.5-10), NO2 and NOx with ASCVD risk in the UK Biobank population. Methods: Among 285,045 participants, pollutants were assessed and correlations between ASCVD risk were stratified by sex and estimated using multiple linear and logistic regressions adjusted for length of time at residence, education, income, physical activity, Townsend deprivation, alcohol, smocking pack years, BMI and rural/urban zone. Results: Males presented higher ASCVD risk than females (8.63% vs. 2.65%, p < 0.001). In males PM2.5, PM10, NO2, and NOx each were associated with an increased ASCVD risk >7.5% in the adjusted logistic models, with ORs [95% CI] for a 10 μg/m3 increase were 2.17 [1.87-2.52], 1.15 [1.06-1.24], 1.06 [1.04-1.08] and 1.05 [1.04-1.06], respectively. In females, the ORs for a 10 μg/m3 increase were 1.55 [1.19-2.05], 1.22 [1.06-1.42], 1.07 [1.03-1.10], and 1.04 [1.02-1.05], respectively. No association was observed in both sexes between ASCVD risk and PM2.5-10. Conclusion: Our findings may suggest the possible actions of air pollutants on ASCVD risk.

Soluble ST2 in Patients with Carotid Artery Stenosis-Association with Plaque Morphology and Long-Term Outcome

Interleukin (IL-33) and the ST2 receptor are implicated in the pathogenesis of atherosclerosis. Soluble ST2 (sST2), which negatively regulates IL-33 signaling, is an established biomarker in coronary artery disease and heart failure. Here we aimed to investigate the association of sST2 with carotid atherosclerotic plaque morphology, symptom presentation, and the prognostic value of sST2 in patients undergoing carotid endarterectomy. A total of 170 consecutive patients with high-grade asymptomatic or symptomatic carotid artery stenosis undergoing carotid endarterectomy were included in the study. The patients were followed up for 10 years, and the primary endpoint was defined as a composite of adverse cardiovascular events and cardiovascular mortality, with all-cause mortality as the secondary endpoint. The baseline sST2 showed no association with carotid plaque morphology assessed using carotid duplex ultrasound (B 0.051, 95% CI -0.145-0.248, p = 0.609), nor with modified histological AHA classification based on morphological description following surgery (B -0.032, 95% CI -0.194-0.130, p = 0.698). Furthermore, sST2 was not associated with baseline clinical symptoms (B -0.105, 95% CI -0.432-0.214, p = 0.517). On the other hand, sST2 was an independent predictor for long-term adverse cardiovascular events after adjustment for age, sex, and coronary artery disease (HR 1.4, 95% CI 1.0-2.4, p = 0.048), but not for all-cause mortality (HR 1.2, 95% CI 0.8-1.7, p = 0.301). Patients with high baseline sST2 levels had a significantly higher adverse cardiovascular event rate as compared to patients with lower sST2 (log-rank p < 0.001). Although IL-33 and ST2 play a role in the pathogenesis of atherosclerosis, sST2 is not associated with carotid plaque morphology. However, sST2 is an excellent prognostic marker for long-term adverse cardiovascular outcomes in patients with high-grade carotid artery stenosis.

Higher Leukocyte Count Is Associated with Lower Presence of Carotid Lipid-Rich Necrotic Core: A Sub-Study in the Plaque at RISK (PARISK) Study

BACKGROUND

Increasing evidence suggests that inflammation inside the vessel wall has a prominent role in atherosclerosis. In carotid atherosclerosis in particular, vulnerable plaque characteristics are strongly linked to an increased stroke risk. An association between leukocytes and plaque characteristics has not been investigated before and could help with gaining knowledge on the role of inflammation in plaque vulnerability, which could contribute to a new target for intervention. In this study, we investigated the association of the leukocyte count with carotid vulnerable plaque characteristics.

METHODS

All patients from the Plaque At RISK (PARISK) study whom had complete data on their leukocyte count and CTA- and MRI-based plaque characteristics were included. Univariable logistic regression was used to detect associations of the leukocyte count with the separate plaque characteristics (intra-plaque haemorrhage (IPH), lipid-rich-necrotic core (LRNC), thin or ruptured fibrous cap (TRFC), plaque ulceration and plaque calcifications). Subsequently, other known risk factors for stroke were included as covariates in a multivariable logistic regression model.

RESULTS

161 patients were eligible for inclusion in this study. Forty-six (28.6%) of these patients were female with a mean age of 70 [IQR 64-74]. An association was found between a higher leukocyte count and lower prevalence of LRNC (OR 0.818 (95% CI 0.687-0.975)) while adjusting for covariates. No associations were found between the leucocyte count and the presence of IPH, TRFC, plaque ulceration or calcifications.

CONCLUSIONS

The leukocyte count is inversely associated with the presence of LRNC in the atherosclerotic carotid plaque in patients with a recently symptomatic carotid stenosis. The exact role of leukocytes and inflammation in plaque vulnerability deserves further attention.