Supracardiac atherosclerosis in embolic stroke of undetermined source: the underestimated source

Prevalence and Factors Associated with Carotid Stenosis in Acute Ischemic Stroke Patients with Atrial Fibrillation

INTRODUCTION

Among stroke patients with atrial fibrillation (AF), it is not uncommon to identify carotid atherosclerosis. This study aimed to estimate the prevalence of, and factors associated with, carotid atherosclerosis among patients with AF and acute ischemic stroke.

PATIENTS AND METHODS

Prospectively collected data from consecutive patients with anterior ischemic stroke and AF who underwent carotid imaging from 10 stroke registries were categorized retrospectively according to the degree of stenosis in: no atherosclerosis, stenosis <50%, stenosis ≥50%, and occlusion. Logistic regression analysis was used to identify factors associated with ipsilateral carotid atherosclerosis.

RESULTS

Among 2,955 patients with ischemic stroke and AF, carotid atherosclerosis was evident in 1,022 (34.6%) patients, while carotid stenosis ≥50% and occlusion were identified in 204 (6.9%) and 168 (5.7%) patients, respectively. Ipsilateral carotid stenosis ≥50% or occlusion was associated with higher age (OR: 1.15, 95% CI: 1.01-1.32, per decade), previous ischemic stroke or transient ischemic attack (OR: 1.70, 95% CI: 1.29-2.25), peripheral artery disease (OR: 1.85, 95% CI: 1.23-2.78), coronary artery disease (OR: 1.53, 95% CI: 1.16-2.04), and statin treatment on admission (OR: 1.30, 95% CI: 1.01-1.67). Patients with lacunar stroke had a lower likelihood of stenosis ≥50% or occlusion (OR: 0.29, 95% CI: 0.13-0.68). Compared to the absence of atherosclerotic disease, atherosclerosis in one and two arterial beds was associated with the identification of ipsilateral carotid stenosis (OR: 1.49, 95% CI: 1.22-2.98 and OR: 3.18, 95% CI: 1.85-5.49, respectively).

CONCLUSION

Among acute ischemic stroke patients with AF, 1 out of 3 had ipsilateral carotid atherosclerosis, and 1 out of 8 had ipsilateral carotid stenosis ≥50% or occlusion. Atherosclerosis in two arterial beds was the most important predictor for the identification of ipsilateral carotid stenosis. Among ischemic stroke patients with AF, carotid atherosclerosis is common, while carotid imaging should not be overlooked, especially in those with coronary or/and peripheral artery disease.

Embolic strokes of undetermined source: a clinical consensus statement of the ESC Council on Stroke, the European Association of Cardiovascular Imaging and the European Heart Rhythm Association of the ESC

One in six ischaemic stroke patients has an embolic stroke of undetermined source (ESUS), defined as a stroke with unclear aetiology despite recommended diagnostic evaluation. The overall cardiovascular risk of ESUS is high and it is important to optimize strategies to prevent recurrent stroke and other cardiovascular events. The aim of clinicians when confronted with a patient not only with ESUS but also with any other medical condition of unclear aetiology is to identify the actual cause amongst a list of potential differential diagnoses, in order to optimize secondary prevention. However, specifically in ESUS, this may be challenging as multiple potential thromboembolic sources frequently coexist. Also, it can be delusively reassuring because despite the implementation of specific treatments for the individual pathology presumed to be the actual thromboembolic source, patients can still be vulnerable to stroke and other cardiovascular events caused by other pathologies already identified during the index diagnostic evaluation but whose thromboembolic potential was underestimated. Therefore, rather than trying to presume which particular mechanism is the actual embolic source in an ESUS patient, it is important to assess the overall thromboembolic risk of the patient through synthesis of the individual risks linked to all pathologies present, regardless if presumed causally associated or not. In this paper, a multi-disciplinary panel of clinicians/researchers from various backgrounds of expertise and specialties (cardiology, internal medicine, neurology, radiology and vascular surgery) proposes a comprehensive multi-dimensional assessment of the overall thromboembolic risk in ESUS patients through the composition of individual risks associated with all prevalent pathologies.

Magnetic resonance imaging for diagnostic workup of embolic stroke of undetermined source: A systematic review

BACKGROUND

Embolic stroke of undetermined source (ESUS) refers to ischemic stroke where the underlying cause of thromboembolism cannot be found despite the recommended diagnostic workup. Unidentified source of emboli hinders clinical decision-making and patient management with detrimental consequences on long-term prognosis. The rapid development and versatility of magnetic resonance imaging (MRI) make it an appealing addition to the diagnostic routine of patients with ESUS for the assessment of potential vascular and cardiac embolic sources.

AIMS

To review the use of MRI in the identification of cardiac and vascular embolic sources in ESUS and to assess the reclassification value of MRI examinations added to the conventional workup of ESUS.

SUMMARY OF REVIEW

We reviewed the use of cardiac and vascular MRI for the identification of a variety of embolic sources associated with ESUS, including atrial cardiomyopathy, left ventricular pathologies, and supracervical atherosclerosis in carotid and intracranial arteries and in distal thoracic aorta. The additional reclassification after MRI examinations added to the workup of patients with ESUS ranged from 6.1% to 82.3% and varied depending on the combination of imaging modalities.

CONCLUSION

MRI techniques allow us to identify additional cardiac and vascular embolic sources and may further decrease the prevalence of patients with the diagnosis of ESUS.

Beyond antithrombotics: recent advances in pharmacological risk factor management for secondary stroke prevention

Patients with ischaemic stroke represent a diverse group with several cardiovascular risk factors and comorbidities, which classify them as patients at very high risk of stroke recurrence, cardiovascular adverse events or death. In addition to antithrombotic therapy, which is important for secondary stroke prevention in most patients with stroke, cardiovascular risk factor assessment and treatment also contribute significantly to the reduction of mortality and morbidity. Dyslipidaemia, diabetes mellitus and hypertension represent common and important modifiable cardiovascular risk factors among patients with stroke, while early recognition and treatment may have a significant impact on patients' future risk of major cardiovascular events. In recent years, there have been numerous advancements in pharmacological agents aimed at secondary cardiovascular prevention. These innovations, combined with enhanced awareness and interventions targeting adherence and persistence to treatment, as well as lifestyle modifications, have the potential to substantially alleviate the burden of cardiovascular disease, particularly in patients who have experienced ischaemic strokes. This review summarises the evidence on the contemporary advances on pharmacological treatment and future perspectives of secondary stroke prevention beyond antithrombotic treatment.

Real-world effectiveness and safety of evolocumab in very high-risk atherosclerotic cardiovascular disease patients with acute ischemic stroke

BACKGROUND

We investigated evolocumab's real-world effectiveness and safety on a background of statin therapy in the acute phase of ischemic stroke (IS) patients with a very high-risk of atherosclerotic cardiovascular disease (ASCVD).

METHODS

A real-world, single-center, retrospective study was conducted in the neurology department at Tianjin Huanhu Hospital in China. Patients were divided into two groups: evolocumab treatment (140 mg every two weeks) or the standard of care (SOC) group. The primary efficacy outcome of the study was the achievement of a targeted lipid control rate and the incidence of major adverse cardiovascular events (MACE) by the end of the follow-up. MACE was defined as a composite of various cardiovascular events, cerebrovascular events such as stroke or TIA, and event-related deaths. Propensity score matching (PSM) analysis was utilized to account for confounding factors between groups. Survival analyses were performed using the Kaplan-Meier method and COX regression modeling.

RESULTS

1080 AIS patients with very high-risk ASCVD were recruited. After PSM, there were 528 individuals, with 206 in the evolocumab group and 322 in the SOC group. At 12 months of follow-up, the proportion of LDL-C < 1.4mmol/L and ≥ 50% reduction was 44.91% in the evolocumab group, compared with only 3.12% of SOC-treated patients (p < 0.01). The median follow-up time for clinical events was 15 months. The evolocumab group was associated with a lower risk of cerebrovascular events compared to the SOC group (HR, 0.45; 95% CI, 0.23-0.89; p = 0.02).

CONCLUSIONS

This real-world study suggested that evolocumab on a background of statin reduced the LDL-C levels significantly and lowered the incidence of recurrent cerebrovascular events in the very high-risk ASCVD patients with AIS in China.

Association between antithrombotic therapy after stroke in patients with atrial fibrillation and the risk of net clinical outcome: an observational cohort study

AIMS

Data on the optimal use of antithrombotic drugs and associated clinical outcomes in patients with atrial fibrillation (AF) and acute ischaemic stroke (IS) are limited. We investigated the prescription patterns of antithrombotics in community practice and long-term clinical prognosis according to early post-stroke antithrombotic therapy in patients with AF and acute IS.

METHODS AND RESULTS

Patients with AF who were admitted for acute IS at a single tertiary hospital in 2010-2020 were retrospectively reviewed. Clinical profiles including the aetiology of stroke and prescription patterns of antithrombotics were identified. The net clinical outcome (NCO)-the composite of recurrent stroke, any bleeding, hospitalization or emergency department visits for cardiovascular (CV) events, and death-was compared according to the antithrombotic therapy at the first outpatient clinic visit [oral anticoagulation (OAC) alone vs. antiplatelet (APT) alone vs. OAC/APT(s)] following discharge. A total of 918 patients with AF and acute IS (mean age, 72.6 years; male, 59.3%; mean CHA₂DS₂-VASc score 3.3) were analysed. One-third (33.9%, n = 310) of patients were simultaneously diagnosed with AF and IS. The most common aetiology of IS was cardioembolism (71.2%), followed by undetermined aetiology (19.8%) and large artery atherosclerosis (6.0%). OAC, APT(s), and concomitant OAC and APT(s) were prescribed in 33.4%, 11.1%, and 53.4% of patients during admission that changed to 67.0%, 9.1%, and 21.7% at the first outpatient clinic, and were mostly continued up to one year after IS. Non-prescription of OAC was observed in 11.3% of post-stroke patients with AF. During a median follow-up of 2.1 years, the overall incidence rate of NCO per 100 patient-year (PY) was 20.14. APT(s) monotherapy presented the highest cumulative risk of NCO (adjusted hazard ratio 1.47, 95% confidence interval 1.08-2.00, P = 0.015; with reference to OAC monotherapy) mainly driven by the highest rates of recurrent stroke and any bleeding. OAC/APT(s) combination therapy was associated with a 1.62-fold significantly higher risk of recurrent stroke (P = 0.040) and marginally higher risk of any bleeding than OAC monotherapy.

CONCLUSION

Approximately one-third of acute IS in AF have a distinctive mechanism from cardioembolism. Although APT was frequently prescribed in post-stroke patients with AF, no additive clinical benefit was observed. Adherence to OAC treatment is essential to prevent further CV adverse events in patients with AF and IS.

Prevalence of high-risk aortic arch atherosclerosis features on computed tomography angiography in embolic stroke of undetermined source

INTRODUCTION

Embolic stroke of undetermined source (ESUS) comprises a heterogenous group. There is a need to further identify etiologies within this group to guide management strategies. We examined the prevalence of aortic arch atherosclerosis (AAA) on CT angiography (CTA) in patients with embolic stroke of undetermined source (ESUS) to characterize high-risk plaque features.

METHODS

All patients from two prospective multicenter acute ischemic stroke studies (INTERRSeCT and PRove-IT) were included if the CTA adequately imaged the proximal aortic arch and the stroke etiology was recorded. Three readers blinded to stroke etiology analyzed the following AAA plaque features on baseline CTA at the time of stroke: 1) thickness in millimetres (mm); 2) morphology (none, smooth, ulcerated, or protruding); 3) location within the aortic arch (proximal, transverse, or distal); and 4) calcification (none, single small, multiple small, single large, or diffuse extensive).

RESULTS

We included 1063 patients, of which 293 (27.6%) had ESUS (mean age 67.5 years; 46.4% men; median NIHSS 12; 80.6% large vessel occlusion). Mean AAA thickness was significantly larger in ESUS patients (3.8 mm) compared to non-ESUS patients (3.0 mm; p<0.0001) and to a subgroup of patients with large artery atherosclerosis (2.9 mm; p=0.003). ESUS patients had a significantly higher proportion of ulcerated or protruding plaques (17.4% vs 10.3%; risk ratio 1.7, 95% C.I. 1.2-2.4, p=0.002). The location of AAA in the ESUS group was the ascending aorta in 37.9%, transverse arch in 42.3%, and descending aorta in 84.6%. Although AAA was mostly located in the distal aortic arch, ulcerated or protruding plaques were least common in the distal arch (p=0.002). There was no difference between ESUS and non-ESUS patients in plaque location (p=0.23) or calcification grade (p=0.092).

CONCLUSION

ESUS patients in our study had thicker AAA and a higher prevalence of ulcerated or protruding plaques located more proximally within the aortic arch. High-risk plaque features may suggest a causal role of AAA in the ESUS population with visible intracranial occlusions.

Age-dependent sex differences in non-stenotic intracranial plaque of embolic stroke of undetermined source

Age and sex have effect on atherosclerosis. This study aimed to investigate their effect on non-stenotic intracranial atherosclerotic plaque (NIAP) in embolic stroke of undetermined source (ESUS) using high-resolution magnetic resonance imaging (HR-MRI). We retrospectively recruited consecutive ESUS patients who underwent intracranial HR-MRI to assess the plaque characteristics (remodeling index [RI], plaque burden [PB], fibrous cap [FC], discontinuity of plaque surface [DPS], intraplaque hemorrhage [IPH] and complicated plaque [CP]). We divided patients into three groups (< 60 years, 60-74 years, ≥ 75 years). 155 patients with ipsilateral NIAP were found from 243 ESUS patients, with 106 men (68.39%) and 49 women (31.61%). In total population or age group under 60 years, there were no significant differences in plaque characteristics between men and women (all p > 0.05). In age group of 60-74 years, men were associated with higher PB (66.27 ± 9.17% vs 60.91 ± 8.86%, p = 0.017) and RI (1.174 vs 1.156, p = 0.019), higher prevalence of DPS (82.50% vs 60.00%, p = 0.036) and complicated plaque (85.00% vs 63.33%, p = 0.036). For subjects ≥ 75 years old, PB were significantly higher in twomen vs men (68.85 ± 6.14% vs 62.62 ± 7.36%, p = 0.040). In addition, the probability for PBupper (≥ median PB), RIupper (≥ median RI) and vulnerable plaque increased as age increased, and its predictive power for index ESUS was higher in men than women. This study identified age-dependent sex differences in NIAP characteristics of ESUS patients, which will help us clarify their etiology.

Arterial Hypertension and Its Consequences Are the Main Predictors of Embolic Stroke of Undetermined Source

Methods

We performed a hospital-based prospective cohort study with 1,317 enrolled participants. We compared patients and healthy volunteers according to the main demographic, anthropometric parameters, stroke risk factors, comorbidities, and data of clinical and instrumental examination. In order to balance the study and the control groups for age and sex, the propensity score matching was performed. In order to generate the overall predictive model, a multivariate analysis was performed using the binary logistic regression method.

Results

The following predictors of ESUS were identified in current study: arterial hypertension (AH); increased heart rate and pulmonary arterial systolic pressure (PASP); the presence of conduction disturbance; the enlargement of left, right atrium, and left ventricle end-systolic length; increased intima-media thickness (IMT) in right and left common carotid artery (CCA); lowered Montreal Cognitive Assessment (MoСA) cognitive scale score; the presence of subcortical microbleeds; central brain atrophy; the larger size of third ventricle; and the higher medial temporal lobe atrophy (MTA) score. The following risk factors were included in the final predictive model: the presence of AH (p < 0.0005; OR = 12.98 (95% CI: 4.53-37.21)) and PASP (p=0.018; OR = 1.13 (95% CI: 1.02-1.25)) and male sex (p=0.046; OR = 2.771 (95% CI: 1.017-7.555)). The Nagelkerke's pseudo-R-squared value was 0.404 and the significance of the Hosmer-Lemeshow test was 0.733, which indicate the goodness of the final logistic regression model.

Conclusions

We propose that AH and its consequences are the main predictors of ESUS. The results of this study emphasize the importance of AH control for primary and secondary prevention of ESUS.

The multifaceted roles of activating transcription factor 3 (ATF3) in inflammatory responses - Potential target to regulate neuroinflammation in acute brain injury

Activating transcription factor 3 (ATF3) is one of the most important transcription factors that respond to and exert dual effects on inflammatory responses. Recently, the involvement of ATF3 in the neuroinflammatory response to acute brain injury (ABI) has been highlighted. It functions by regulating neuroimmune activation and the production of neuroinflammatory mediators. Notably, recent clinical evidence suggests that ATF3 may serve as a potential ideal biomarker of the long-term prognosis of ABI patients. This mini-review describes the essential inflammation modulatory roles of ATF3 in different disease contexts and summarizes the regulatory mechanisms of ATF3 in the ABI-induced neuroinflammation.

Characteristics of intracranial plaque in patients with non-cardioembolic stroke and intracranial large vessel occlusion

OBJECTIVE

To determine the characteristics of intracranial plaque proximal to large vessel occlusion (LVO) in stroke patients without major-risk cardioembolic source using 3.0 T high-resolution MRI (HR-MRI).

METHODS

We retrospectively enrolled eligible patients from January 2015 to July 2021. The multidimensional parameters of plaque such as remodelling index (RI), plaque burden (PB), percentage lipid-rich necrotic core (%LRNC), presence of discontinuity of plaque surface (DPS), fibrous cap rupture, intraplaque haemorrhage and complicated plaque were evaluated by HR-MRI.

RESULTS

Among 279 stroke patients, intracranial plaque proximal to LVO was more prevalent in the ipsilateral versus contralateral side to stroke (75.6% vs 58.8%, p<0.001). The larger PB (p<0.001), RI (p<0.001) and %LRNC (p=0.001), the higher prevalence of DPS (61.1% vs 50.6%, p=0.041) and complicated plaque (63.0% vs 50.6%, p=0.016) were observed in the plaque ipsilateral versus contralateral to stroke. Logistic analysis showed that RI and PB were positively associated with an ischaemic stroke (RI: crude OR: 1.303, 95% CI 1.072 to 1.584, p=0.008; PB: crude OR: 1.677, 95% CI 1.381 to 2.037, p<0.001). In subgroup with <50% stenotic plaque, the greater PB, RI, %LRNC and the presence of complicated plaque were more closely related to stroke, which was not evident in subgroup with ≥50% stenotic plaque.

CONCLUSION

This is the first study to report the characteristics of intracranial plaque proximal to LVO in non-cardioembolic stroke. It provides potential evidence to support different aetiological roles of <50% stenotic vs ≥50% stenotic intracranial plaque in this population.

Imaging Carotid Plaque Inflammation Using Positron Emission Tomography: Emerging Role in Clinical Stroke Care, Research Applications, and Future Directions

Atherosclerosis is a chronic systemic inflammatory condition of the vasculature and a leading cause of stroke. Luminal stenosis severity is an important factor in determining vascular risk. Conventional imaging modalities, such as angiography or duplex ultrasonography, are used to quantify stenosis severity and inform clinical care but provide limited information on plaque biology. Inflammatory processes are central to atherosclerotic plaque progression and destabilization. 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) is a validated technique for quantifying plaque inflammation. In this review, we discuss the evolution of FDG-PET as an imaging modality to quantify plaque vulnerability, challenges in standardization of image acquisition and analysis, its potential application to routine clinical care after stroke, and the possible role it will play in future drug discovery.

Reclassification and risk stratification of embolic stroke of undetermined source by ASCOD phenotyping

BACKGROUND

Common vascular diseases underlying stroke, including atherosclerosis, small-vessel disease (SVD), and cardioembolic pathology, can be present in patients with embolic stroke of undetermined source (ESUS), although these are not direct causes of stroke.

AIMS

To describe the frequency and degree of the three major diseases using atherosclerosis, SVD, cardiac pathology, other causes, and dissection (ASCOD) phenotyping and to assess their prognostic implications in ESUS.

METHODS

In this prospective observational study, 221 patients with ESUS within 1 week of onset were consecutively enrolled and followed up for 1 year. Vascular diseases associated with stroke were assessed using the ASCOD classification. The primary outcome was a composite of nonfatal stroke, nonfatal acute coronary syndrome, and vascular death.

RESULTS

Among 221 patients (mean age, 69.6 years; male, 59.7%), 135 (61.1%), 102 (46.2%), and 107 (48.4%) had any grade of atherosclerosis (A2 or A3), SVD (S3), and cardiac pathology (C2 or C3), respectively. ESUS patients graded as A2 or A3 (i.e. ipsilateral atherosclerotic plaque, contralateral ⩾ 50% stenosis, or aortic arch plaque) were at a significantly higher risk of composite vascular events than those graded as A0 (i.e. no atherosclerotic disease) (adjusted hazard ratio (95% confidence interval), 2.40 (1.01-5.72). No differences were observed in the event risk between patients with S3 (i.e. magnetic resonance imaging evidence of SVD) and S0 (i.e. no SVD) and between those with C2 or C3 (i.e. presence of any cardiac pathology) and C0 (i.e. no cardiac abnormalities).

CONCLUSIONS

Atherosclerotic diseases corresponding to ASCOD grade A2 or A3 were predictive of recurrent vascular events in ESUS patients. Reclassification of ESUS using ASCOD phenotyping provides important clues for risk prediction and may guide optimal management strategies.

Neutrophil extracellular traps: A novel target for the treatment of stroke

Stroke is a threatening cerebrovascular disease caused by thrombus with high morbidity and mortality rates. Neutrophils are the first to be recruited in the brain after stroke, which aggravate brain injury through multiple mechanisms. Neutrophil extracellular traps (NETs), as a novel regulatory mechanism of neutrophils, can trap bacteria and secret antimicrobial molecules, thereby degrading pathogenic factors and killing bacteria. However, NETs also exacerbate certain non-infectious diseases by activating autoimmune or inflammatory responses. NETs have been found to play important roles in the pathological process of stroke in recent years. In this review, the mechanisms of NETs formation, the physiological roles of NETs, and the dynamic changes of NETs after stroke are summarized. NETs participate in stroke through various mechanisms. NETs promote the coagulation cascade and interact with platelets to induce thrombosis. tPA induces the degranulation of neutrophils to form NETs, leading to hemorrhagic transformation and thrombolytic resistance. NETs aggravate stroke by mediating inflammation, atherosclerosis and vascular injury. In addition, the regulation of NETs in stroke, the potential of NETs as biomarker and the treatment of stroke targeting NETs are discussed. The increasing evidences suggest that NETs may be a potential target for stroke treatment. Inhibition of NETs formation or promotion of NETs degradation plays protective effects in stroke. However, how to avoid the adverse effects of NETs-targeted therapy deserves further study. In summary, this review provides a reference for the pathogenesis, drug targets, biomarkers and drug development of NETs in stroke.

The role of non-stenosing carotid artery plaques in embolic stroke of undetermined source, is it a silent offender? A review of literature

PURPOSE

Atherosclerotic cervical internal carotid artery disease is one of the major causes of ischemic stroke and transient ischemic attacks. The risk of stroke from mild to moderate stenoses (i.e. <50% stenosis) might be underestimated. There is increasing evidence that plaque morphological features reflect plaque instability that may harbor high risk for embolization. In this narrative review, we will review the literature on plaque features that predict vulnerability beyond the degree of stenosis, discuss the clinical association with stroke, and evaluate the evidence that these lesions serve as a source for embolic stroke of unknown source (ESUS).

METHODS

We performed a literature search using PubMed, EMBASE, and Web of Science. The terms "embolic stroke of undetermined source" and "plaque morphology" were used either alone or in combination with "non-flow limiting stenosis," "non-stenosing plaques," "high-risk plaque features" or "internal carotid artery plaque." Data on plaque morphology and ESUS were mainly taken from review articles, observational studies including retrospective cohort and cross-sectional studies, meta-analyses, and systematic reviews.

CONCLUSION

Nonstenosing carotid artery plaques with high-risk features carry a remarkable risk for stroke occurrence and randomized clinical trials are warranted for further evaluation of using carotid artery stenting or carotid endarterectomy to mitigate the risk of stroke.

Atherosclerosis as a Potential Cause of Deep Embolic Stroke of Undetermined Source: A 3T High‐Resolution Magnetic Resonance Imaging Study

Background

The potential causes or sources of embolic stroke of undetermined source (ESUS) vary. This study aimed to investigate the main cause of deep ESUS by evaluating nonstenotic intracranial atherosclerotic plaque.

Methods and Results

We retrospectively screened consecutive patients with unilateral anterior circulation ESUS. After excluding the patients with possible embolism from an extracranial artery such as aortic arch plaque, carotid plaque, and so on, the enrolled patients with ESUS were categorized into 2 groups: deep ESUS and cortical with/without deep ESUS. All patients underwent intracranial high‐resolution magnetic resonance imaging to assess the characteristics of nonstenotic intracranial atherosclerotic plaque. Biomarkers of atrial cardiopathy (ie, P‐wave terminal force in lead V1 on ECG, NT‐proBNP [N‐terminal pro–brain natriuretic peptide] and left atrial diameter) were collected. A total of 155 patients with ipsilateral nonstenotic intracranial atherosclerotic plaque were found, with 76 (49.0%) in deep ESUS and 79 (51.0%) in cortical with/without deep ESUS. We found more prevalent plaque in the M1 segment of the middle cerebral artery and the ostia of the perforator, with a smaller remodeling index plaque burden, and less frequent occurrence of complicated plaque in deep ESUS versus cortical with/without deep ESUS. Higher BNP (brain natriuretic peptide) levels and a higher prevalence of atrial cardiopathy in cortical with/without deep ESUS versus deep ESUS. Moreover, the discrimination of vulnerable plaque for predicting ESUS was significantly enhanced after adjusting for or further excluding patients with deep ESUS.

Conclusions

The current study provides the first high‐resolution magnetic resonance imaging evidence that cortical with/without deep ESUS and deep ESUS should be 2 distinct entities and that atherosclerosis, not embolism, might be the main cause of deep ESUS.

Characteristics of non-stenotic carotid plaque in embolic stroke of undetermined source compared with cardiogenic embolism: a retrospective cross-sectional observational study

Background

Non-stenotic carotid plaque is considered an important etiology of embolic stroke of undetermined source (ESUS). However, only a few previous studies included a negative control group, and the characteristics of non-stenotic carotid plaque in ESUS have yet to be investigated. The objective of this study is to explore the clinical characteristics of ESUS and the correlation between non-stenotic carotid plaque and ESUS.

Methods

This is a single-center, retrospective cross-sectional observational study conducted to compare differences in clinical information among ESUS, CE, and large-artery atherosclerosis (LAA), as well as the prevalence of non-stenotic carotid plaque and non-stenotic carotid plaque with low echo between patients with ESUS and CE in Changzhou No.2 People’s Hospital from January 2020 to January 2022. Ultrasound was used to evaluate the characteristics of non-stenotic carotid plaque and vulnerable carotid plaque was defined as plaque with low echo. The binary logistic regression model was used to analyze the relationship between the characteristics of non-stenotic carotid plaque and ESUS. The receiver-operating characteristic curve was used to evaluate the diagnostic efficiency of the characteristics of non-stenotic carotid plaque for ESUS.

Results

We had a final studying population of 280 patients including 81 with ESUS, 37 with CE, and 162 with LAA. There were no differences in clinical features between ESUS and LAA, but in the comparison of CE and ESUS, there were differences in age, smoking, hypertension, levels of triglyceride, total cholesterol, and low density lipoprotein cholesterol. In ESUS, the prevalence of non-stenotic carotid plaque was more common on the ipsilateral side of stroke than in CE [55 (67.90%) vs. 18 (48.65%), p = 0.046], so was the prevalence of non-stenotic carotid plaque with low echo [38 (46.91%) vs. 5 (13.51%), p < 0.001]. Logistic regression analysis showed that the prevalence of non-stenotic carotid plaque (OR: 4.19; 95% CI: 1.45–12.11; p = 0.008) and the prevalence of non-stenotic carotid plaque with low echo (OR: 5.12; 95% CI: 1.55–16.93; p = 0.007) were, respectively, the independent predictors of ESUS. The results receiver-operating characteristic (ROC) curve showed that the combination of age, hypertension, and ipsilateral non-stenotic carotid plaque with low echo had the best diagnostic efficiency for ESUS (0.811; 95%CI: 0.727–0.896; p < 0.001).

Conclusion

Our results suggest that ipsilateral vulnerable non-stenotic carotid plaque is associated with ESUS in anterior circulation infarction.

Vessel wall MR imaging of aortic arch, cervical carotid and intracranial arteries in patients with embolic stroke of undetermined source: A narrative review

Despite advancements in multi-modal imaging techniques, a substantial portion of ischemic stroke patients today remain without a diagnosed etiology after conventional workup. Based on existing diagnostic criteria, these ischemic stroke patients are subcategorized into having cryptogenic stroke (CS) or embolic stroke of undetermined source (ESUS). There is growing evidence that in these patients, non-cardiogenic embolic sources, in particular non-stenosing atherosclerotic plaque, may have significant contributory roles in their ischemic strokes. Recent advancements in vessel wall MRI (VW-MRI) have enabled imaging of vessel walls beyond the degree of luminal stenosis, and allows further characterization of atherosclerotic plaque components. Using this imaging technique, we are able to identify potential imaging biomarkers of vulnerable atherosclerotic plaques such as intraplaque hemorrhage, lipid rich necrotic core, and thin or ruptured fibrous caps. This review focuses on the existing evidence on the advantages of utilizing VW-MRI in ischemic stroke patients to identify culprit plaques in key anatomical areas, namely the cervical carotid arteries, intracranial arteries, and the aortic arch. For each anatomical area, the literature on potential imaging biomarkers of vulnerable plaques on VW-MRI as well as the VW-MRI literature in ESUS and CS patients are reviewed. Future directions on further elucidating ESUS and CS by the use of VW-MRI as well as exciting emerging techniques are reviewed.

Fine-tuning of microglia polarization prevents diabetes-associated cerebral atherosclerosis

Diabetes increases the occurrence and severity of atherosclerosis. When plaques form in brain vessels, cerebral atherosclerosis causes thickness, rigidity, and unstableness of cerebral artery walls, leading to severe complications like stroke and contributing to cognitive impairment. So far, the molecular mechanism underlying cerebral atherosclerosis is not determined. Moreover, effective intervention strategies are lacking. In this study, we showed that polarization of microglia, the resident macrophage in the central nervous system, appeared to play a critical role in the pathological progression of cerebral atherosclerosis. Microglia likely underwent an M2c-like polarization in an environment long exposed to high glucose. Experimental suppression of microglia M2c polarization was achieved through transduction of microglia with an adeno-associated virus (serotype AAV-PHP.B) carrying siRNA for interleukin-10 (IL-10) under the control of a microglia-specific TMEM119 promoter, which significantly attenuated diabetes-associated cerebral atherosclerosis in a mouse model. Thus, our study suggests a novel translational strategy to prevent diabetes-associated cerebral atherosclerosis through in vivo control of microglia polarization.

The characteristics of intracranial plaques of unilateral, anterior circulation embolic stroke of undetermined source: an analysis of different subtypes based on high-resolution imaging

BACKGROUND AND PURPOSE

To investigate the characteristics of non-stenotic intracranial plaque (NSIP) among embolic stroke of undetermined source (ESUS) subtypes by high-resolution magnetic resonance imaging (HR-MRI).

METHODS

we retrospectively enrolled consecutive patients with ESUS who were mandatory for HR-MRI. Based the location and arterial supply of the infarct, ESUS were categorized into three types: cortical ESUS, subcortical ESUS and mixed ESUS. The NSIP parameters including plaque location, morphology (plaque distribution, remodeling index and plaque burden) and composition (thick fibrous cap, discontinuity of plaque surface, intraplaque hemorrhage and complicated plaque) were evaluated among subtypes.

RESULTS

Among 243 patients, there were 87 (35.8%) cortical ESUS, 127 (52.3%) subcortical ESUS and 29 (11.9%) mixed ESUS. We found significant differences in plaque location (P < 0.001), plaque quadrant (P < 0.001), remodeling index (P < 0.001), plaque burden (P < 0.001), discontinuity of plaque surface (P < 0.001), intraplaque hemorrhage (P = 0.001) and complicated plaque (P < 0.001) of ipsilateral NISP among different ESUS subtypes, except for fibrous cap (P = 0.135). But we found no differences among contralateral NISP. In addition, the clinical characteristics of the differences among ESUS subtypes were striking, including age (P = 0.004), initial National Institute of Health Stroke Scale (P < 0.001), coronary artery disease (P = 0.039), serum urea (P = 0.011) and creatinine (P = 0.002).

CONCLUSION

This is the first report of significantly heterogeneous characteristics of ipsilateral NSIP and clinical findings among ESUS subtypes, which may suggest their different underlying mechanisms.

The Relationship Between Aortic Arch Calcification and Recurrent Stroke in Patients With Embolic Stroke of Undetermined Source-A Case-Control Study

Background

Aortic arch calcification (AoAC) is associated with plaque development and cardiovascular events. We aimed to estimate the predictive value of AoAC for stroke recurrence in patients with embolic stroke of undetermined source (ESUS).

Methods

Consecutive patients with ESUS who were admitted to our center between October 2019 and October 2020 and who had a 1-year follow-up of stroke recurrence were retrospectively reviewed. According to our AoAC grading scale (AGS), AoAC was classified into four grades based on chest computed tomography (CT) findings: no visible calcification (grade 0), spotty calcification (grade 1), lamellar calcification (grade 2), and circular calcification (grade 3).

Results

Of the 158 patients with ESUS (age, 62.1 ± 14.5 years; 120 men) enrolled, 24 (15.2%) had recurrent stroke within a 1-year follow-up. The Cox regression analysis showed that stroke history [hazard ratio (HR), 4.625; 95% confidence interval (CI), 1.828–11.700, p = 0.001] and AoAC (HR, 2.672; 95% CI, 1.129–6.319; p = 0.025) predicted recurrent stroke. AGS grade 1 was associated with a significantly higher risk of stroke recurrence than AGS grade 0 (HR, 5.033; 95% CI, 1.858–13.635, p = 0.001) and AGS grade 2 plus 3 (HR, 3.388; 95% CI, 1.124–10.206, p = 0.030). In patients with AoAC, receiver operating characteristic (ROC) analysis showed that AGS had a good value in predicting stroke recurrence in patients with ESUS, with an area under curve (AUC) of 0.735 (95% CI = 0.601–0.869, p = 0.005).

Conclusions

Aortic arch calcification, especially spotty calcification, had a good predictive value for stroke recurrence in patients with ESUS.

Review and update of the concept of embolic stroke of undetermined source

Ischaemic strokes have traditionally been classified according to the TOAST criteria, in which strokes with unclear aetiology are classified as cryptogenic strokes. However, the definition of cryptogenic stroke did not meet the operational criteria necessary to define patient populations for randomized treatment trials. To address this problem, the concept of embolic stroke of undetermined source (ESUS) was developed and published in 2014. A hypothesis that underpinned this concept was that most strokes in patients with ESUS are caused by embolic events, perhaps many cardioembolic, and that anticoagulation would prevent secondary ischaemic events. On this basis, two large randomized trials were conducted to compare the non-vitamin K antagonist oral anticoagulants (NOACs) dabigatran and rivaroxaban with aspirin. Neither NOAC was superior to aspirin in these trials, although subgroups of patients with ESUS seemed to benefit specifically from anticoagulation or antiplatelet therapy. The neutral results of the trials of anticoagulation and insights into ESUS from research conducted since the concept was introduced warrant reassessment of the ESUS construct as a research concept and a treatment target. In this Review, we discuss the evidence produced since the concept of ESUS was introduced, and propose updates to the criteria and diagnostic algorithm in light of the latest knowledge.

Atrial cardiopathy and non-stenotic intracranial complicated atherosclerotic plaque in patients with embolic stroke of undetermined source

OBJECTIVE

To assess (1) the association between atrial cardiopathy (AC) and non-stenotic intracranial complicated atherosclerotic plaque (NICAP) in patients with embolic stroke of undetermined source (ESUS) or small-vessel disease (SVD), and (2) the performance of previously proposed biomarkers to identify AC as the underlying aetiology in ESUS.

METHODS

Based on our high-resolution MRI (HR-MRI) cohort, 403 subjects (243 ESUS and 160 SVD) were enrolled in the final analysis. All patients underwent intracranial HR-MRI to assess the presence of ipsilateral NICAP. Biomarkers of AC (ie, P-wave terminal force in lead V1 (PTFV1) on ECG, N-terminal probrain natriuretic peptide (NT-proBNP), high-sensitivity cardiac troponin T and left atrial diameter) were collected within 24 hours after admission.

RESULTS

Among patients without ipsilateral NICAP, we found an association between the presence of AC (adjusted OR (aOR): 4.76, 95% CI 2.48 to 9.14), increased PTFV1 (aOR: 5.70, 95% CI: 2.43 to 13.39) and NT-proBNP (aOR: 1.65, 95% CI: 1.16 to 2.35) with ESUS. This association was not evident among patients with ipsilateral NICAP. The discrimination between ESUS versus SVD by AC/AC-related biomarkers was significantly improved after excluding ipsilateral NICAP. Similarly, the discrimination between ESUS and SVD by ipsilateral NICAP was notably augmented after excluding AC, PTFV1 and NT-proBNP.

INTERPRETATION

AC is more prevalent in patients who had ESUS without ipsilateral NICAP compared with patients with, implying that AC and ipsilateral NICAP are two distinct, competing aetiologies of ESUS. Among the AC biomarkers studied in this analysis, PTFV1 seems to be the most informative.

Lipid-related protein NECTIN2 is an important marker in the progression of carotid atherosclerosis: An intersection of clinical and basic studies

Background:

The nectin cell adhesion molecule 2 (NECTIN2) protein is a cell adhesion molecule involved in lipid metabolism. We aimed to explore the potential role of NECTIN2 in carotid atherosclerosis (CA).

Materials and Methods:

Patients who underwent carotid endarterectomy (CEA) at the First Affiliated Hospital of Zhengzhou University were enrolled in this study. APOE-/- rats fed western or normal diet were used to model early pathological changes in CA. The relationship between patients’ lipid indices and plaque severity was assessed using ordinal regression analysis. Mendelian randomisation (MR) analysis was used to determine the causal links between low-density lipoprotein cholesterol (LDL-C) and atherosclerosis. After matching analysis of the single-cell transcriptome and microarray data of carotid plaques, NECTIN2 was identified as a key factor affecting CA. The importance of NECTIN2 was further verified by immunofluorescence staining of CEA and APOE-/- rat specimens.

Results:

A total of 108 patients were included. The traditional lipid indices did not correlate significantly with the plaque severity (P > 0.05). NECTIN2 provided a strong causal link between LDL-C level and CA (MR effect size >0). Deep-sequencing data illustrated that NECTIN2 expression was cell specific. In early-stage CA, NECTIN2 expression was increased in endothelial cells; however, in advanced-stage CA, NECTIN2 was overexpressed in macrophages located in fibrous caps. APOE-/- rat carotid artery and human carotid plaques modelled the entire atherosclerotic process, showing an upregulation of NECTIN2 expression in CA.

Conclusions:

Lipid-related protein NECTIN2 is a potential marker in CA progression and can potentially be a new therapeutic target for clinical prevention.

Immunomodulation and Reduction of Thromboembolic Risk in Hospitalized COVID-19 Patients: Systematic Review and Meta-Analysis of Randomized Trials

Background: We aimed to investigate the potential beneficial effect of immunomodulation therapy on the thromboembolic risk in hospitalized COVID-19 patients. Methods: We searched PubMed and Scopus for randomized trials reporting the outcomes of venous thromboembolism (VTE), ischemic stroke or systemic embolism, myocardial infarction, any thromboembolic event, and all-cause mortality in COVID-19 patients treated with immunomodulatory agents. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using the Mantel–Haenszel random effects method. Results: Among 8499 patients hospitalized with COVID-19, 4638 were treated with an immunomodulatory agent, 3861—with usual care only. Among the patients prescribed immunomodulatory agents, there were 1.77 VTEs per 100 patient-months compared to 2.30 among those treated with usual care (OR: 0.84, 95% CI: 0.61–1.16; I²: 0%). Among the patients who received an interleukin 6 (IL-6) antagonist, VTEs were reported in 12 among the 1075 patients compared to 20 among the 848 receiving the usual care (OR: 0.52, 95% CI: 0.22–1.20; I²: 6%). Immunomodulators as an add-on to usual care did not reduce the risk of stroke or systemic embolism (OR: 1.10, 95% CI: 0.50–2.40; I²: 0%) or of myocardial infarction (OR: 1.06, 95% CI: 0.47–2.39; I²: 0%) and there was a nonsignificant reduction in any thromboembolic event (OR: 0.86, 95% CI: 0.65–1.14; I²: 0%). Conclusions: We did not identify a statistically significant effect of immunomodulation on prevention of thromboembolic events in COVID-19. However, given the large effect estimate for VTE prevention, especially in the patients treated with IL-6 antagonists, we cannot exclude a potential effect of immunomodulation.

Characteristics and prognosis of patients with embolic stroke of undetermined source in China

BACKGROUND AND PURPOSE

We aimed to explore the frequencies, risk factors, and natural history of embolic stroke of undetermined source (ESUS) through a national prospective registry in China.

METHODS

Between August 2015 and March 2018, the Third China National Stroke Registry recruited consecutive patients with ischemic stroke or transient ischemic attack in China. The baseline characteristics, risks of stroke, and prognosis in patients with embolic stroke of undetermined source were described and compared with that in patients with other causative subtypes.

RESULTS

A total of 15,166 transient ischemic attack and ischemic stroke patients were enrolled in the Third China National Stroke Registry. Among 8528 ischemic stroke with standard diagnostic work-up, 2415 (28.3%) patients were diagnosed with embolic stroke of undetermined source. The mean age was 61 years and 70% of them were male. Compared to patients with cardioembolic strokes and small vessel disease, patients with embolic stroke of undetermined source had higher prevalence of nonstenosing large artery atherosclerosis (37.93% vs. 31.26%, P = 0.008 and 37.93% vs. 34.40%, P = 0.044 respectively). The cumulative probability of stroke recurrence in patients with embolic stroke of undetermined source at three months and one year was 5.59% and 8.74%. Compared with embolic stroke of undetermined source patients (0.70% and 1.99%), patients with the large artery atherosclerosis and cardioembolic strokes had higher cumulative probability of death at three months (1.94% and 3.22%) and one year (4.17% and 7.39%).

CONCLUSIONS

Embolic stroke of undetermined source is a common cause of ischemic stroke in Chinese population with a higher stroke recurrence than previously reported. It was more likely to have nonstenosing large artery atherosclerosis in patients with embolic stroke of undetermined source than with cardioembolic strokes and small vessel disease.

Atrial cardiopathy in embolic stroke of undetermined source

INTRODUCTION

Atrial cardiopathy is one of the most common potential sources of thromboembolism for embolic stroke of undetermined source (ESUS). The study aims to investigate the incidence of atrial cardiopathy (defined by severe left atrial enlargement (sLAE) or elevated serum N-terminal pro-B-type natriuretic peptide (NT-proBNP) > 250 pg/ml) in patients with ESUS and compare with other stroke subtypes.

METHODS

We retrospectively collected data of 936 consecutive patients with diffusion-weighted imaging-confirmed acute ischemic stroke. The incidence of atrial cardiopathy was examined in ESUS, large artery atherosclerosis (LAA), and small vessel disease (SVD) strokes. Clinical characteristics were compared between ESUS patients with atrial cardiopathy (AC-ESUS) and patients with atrial fibrillation-induced cardioembolism (AF-CE) stroke.

RESULTS

245 patients were diagnosed with ESUS, while others were diagnosed with LAA (n = 312), SVD (n = 258), and AF-CE (n = 121) strokes. The incidence of sLAE in ESUS patients was higher than in LAA or SVD group (5.3% vs. 1.6% and 1.2%, respectively, p = .005) and higher than in combined LAA/SVD group (5.3% vs. 1.4%, p = .001). The incidence of elevated serum NT-proBNP in ESUS patients was not statistically different from that in LAA or SVD group. Compared with patients with AF-CE stroke, AC-ESUS patients had milder manifestations, had less hemorrhagic transformation, had better short-term outcome, and had fewer in-hospital complications.

CONCLUSIONS

The incidence of sLAE was higher in ESUS patients than in patients with noncardioembolic strokes. AC-ESUS was milder when compared to AF-CE stroke.

Intracranial Atherosclerotic Plaque as a Potential Cause of Embolic Stroke of Undetermined Source

BACKGROUND

Previous studies investigated the potential mechanism of embolic stroke of undetermined source (ESUS) from extracranial artery plaque, but there has been no study other than a case report on high-risk intracranial plaque in ESUS.

OBJECTIVES

The aim of this study was to investigate the issue by evaluating the morphology and composition of intracranial plaque in patients with ESUS and small-vessel disease (SVD) using 3.0-T high-resolution magnetic resonance imaging.

METHODS

Two hundred forty-three consecutive patients with ESUS and 160 patients with SVD-associated stroke between January 2015 and December 2019 were retrospectively enrolled. Multidimensional parameters involving the presence of plaque on both sides, including remodeling index (RI), plaque burden, presence of discontinuity of plaque surface, thick fibrous cap, intraplaque hemorrhage, and complicated American Heart Association type VI plaque at the maximal luminal narrowing site, were evaluated using intracranial high-resolution magnetic resonance imaging.

RESULTS

Among 243 patients with ESUS, the prevalence of intracranial plaque was much higher in the ipsilateral than the contralateral side (63.8% vs. 42.8%; odds ratio [OR]: 5.25; 95% confidence interval [CI]: 2.83 to 9.73), a finding that was not evident in patients with SVD (35.6% vs. 30.6%; OR: 2.14; 95% CI: 0.87 to 5.26; p = 0.134). Logistic analysis showed that RI was independently associated with ESUS in model 1 (OR: 2.329; 95% CI: 1.686 to 3.217; p < 0.001) and model 2 (OR: 2.295; 95% CI: 1.661 to 3.172; p < 0.001). RI alone with an optimal cutoff of 1.162, corresponding to an area under the curve of 0.740, had good diagnostic efficiency for ESUS.

CONCLUSIONS

The present study supports an etiologic role of high-risk nonstenotic intracranial plaque in ESUS.

Per-pass analysis of acute ischemic stroke clots: impact of stroke etiology on extracted clot area and histological composition

Background

Initial studies investigating correlations between stroke etiology and clot composition are conflicting and do not account for clot size as determined by area. Radiological studies have shown that cardioembolic strokes are associated with shorter clot lengths and lower clot burden than non-cardioembolic clots.

Objective

To report the relationship between stroke etiology, extracted clot area, and histological composition at each procedural pass.

Methods

As part of the multi-institutional RESTORE Registry, the Martius Scarlett Blue stained histological composition and extracted clot area of 612 per-pass clots retrieved from 441 patients during mechanical thrombectomy procedures were quantified. Correlations with clinical and procedural details were investigated.

Results

Clot composition varied significantly with procedural passes; clots retrieved in earlier passes had higher red blood cell content (H4=11.644, p=0.020) and larger extracted clot area (H4=10.730, p=0.030). Later passes were associated with significantly higher fibrin (H4=12.935, p=0.012) and platelets/other (H4=15.977, p=0.003) content and smaller extracted clot area. Large artery atherosclerotic (LAA) clots were significantly larger in the extracted clot area and more red blood cell-rich than other etiologies in passes 1–3. Cardioembolic and cryptogenic clots had similar histological composition and extracted clot area across all procedural passes.

Conclusion

LAA clots are larger and associated with a large red blood cell-rich extracted clot area, suggesting soft thrombus material. Cardioembolic clots are smaller in the extracted clot area, consistent in composition and area across passes, and have higher fibrin and platelets/other content than LAA clots, making them stiffer clots. The per-pass histological composition and extracted clot area of cryptogenic clots are similar to those of cardioembolic clots, suggesting similar formation mechanisms.

Atrial Cardiopathy and Likely Pathogenic Patent Foramen Ovale in Embolic Stroke of Undetermined Source

BACKGROUND

 Atrial cardiopathy and likely pathogenic patent foramen ovale (PFO) are two potential embolic sources in patients with embolic stroke of undetermined source (ESUS). The relationship between these two mechanisms among ESUS patients remains unclear.

METHODS

 Atrial cardiopathy was defined as increased left atrial diameter index (> 23 mm/m²) or left atrial volume index (> 34 mL/m²), or PR prolongation (≥ 200 ms), or presence of supraventricular extrasystoles in the electrocardiograms performed during hospitalization for the index stoke. The presence of PFO was assessed by transthoracic echocardiography with microbubble test or by transesophageal echocardiography. The presence of PFO was considered as likely pathogenic if the Risk of Paradoxical Embolism score was 7 to 10.

RESULTS

 Among 367 ESUS patients with available information about the presence of PFO and the presence of atrial cardiopathy (median age: 61 years, 40.6% women), likely pathogenic PFO was diagnosed in 62 (16.9%) and atrial cardiopathy in 122 (33.2%). Only 4 patients (1.1%) had both likely pathogenic PFO and atrial cardiopathy. The prevalence of atrial cardiopathy was lower in patients with likely pathogenic PFO (6.5%) compared with patients with likely incidental PFO (31.2%) or without PFO (40.6%) (Pearson's chi-square test: 26.08, p < 0.001; adjusted odds ratio [OR]: 0.28, 95% confidence interval [CI]: 0.09-0.86). The prevalence of likely pathogenic PFO was lower in patients with atrial cardiopathy compared with patients without atrial cardiopathy (3.3% vs. 23.7%, respectively [Pearson's chi-square test: 24.13, p < 0.001; adjusted OR: 0.2, 95% CI: 0.02-0.6]).

CONCLUSION

 The presence of atrial cardiopathy is inversely related to the presence of likely pathogenic PFO in patients with ESUS.

Intraluminal Carotid Artery Thrombus in COVID-19: Another Danger of Cytokine Storm?

Coronavirus disease 2019 (COVID-19) is associated with a severe inflammatory response. Inflammation affects atherosclerotic plaque vulnerability and promotes a thrombogenic environment. We report a series of 6 patients with COVID-19 with acute ischemic stroke due to intraluminal carotid artery thrombus presenting during an 8-day period. Six patients were included (5 men) with a mean age of 65.8 years (range, 55-78 years). COVID-19 was diagnosed by detection of Severe Acute Respiratory Syndrome coronavirus 2 in 5 patients and was presumed due to typical clinical and imaging findings in 1 patient. All patients had vascular risk factors including diabetes (83%), hyperlipidemia (100%), and smoking (17%). Four patients presented with large infarcts with initial NIHSS scores of 24-30. During their hospitalization, all patients had elevated D-dimer and C-reactive protein levels, 5 patients had elevated lactate dehydrogenase and ferritin levels, 3 had elevated interleukin-6 levels, and 2 had elevated troponin levels. Inflammation related to COVID-19 may result in rupture of vulnerable atherosclerotic plaques, resulting in thrombosis and acute ischemic stroke.