Cause and Mechanisms of Intracranial Atherosclerosis

Effect of atherogenic index of plasma and triglyceride-glucose index on early neurological deterioration of patients with large artery atherosclerotic ischemic stroke

BACKGROUND

Stroke due to large artery atherosclerosis (LAA-stroke) has a poor early prognosis despite appropriate medical treatment. Recently, various parameters reflecting pathological conditions such as insulin resistance or atherogenic dyslipidemia have been proposed using triglyceride (TG) and other biomarkers. In this study, we evaluated the association between TG andTG-related parameters and early neurological deterioration (END) in patients with acute LAA stroke.

METHODS

We evaluated consecutive patients with acute LAA-stroke between January 2010 and December 2020. TG-related parameters were calculated using the following formulas: the atherogenic index of plasma (AIP) = log10 (TG level/high-density lipoprotein level) and TG-glucose (TyG) index = Ln (TG level x glucose level/2). END was defined as an increase of ≥ 2 in the total National Institutes of Health Stroke Scale (NIHSS) score or ≥ 1 in the motor NIHSS score within the first 72 h of admission.

RESULTS

Six hundred and forty patients with acute LAA-stroke were evaluated. In multivariable analyses, AIP (adjusted odds ratio [aOR]: 1.93, 95% confidence interval: 1.32-2.82) was closely associated with END after adjustment for confounders. The TyG index (aOR: 2.22, 95% confidence interval: 1.51-3.27) also showed close association with END. The AIP and TyG index showed significant differences between the END and no END groups only in patients with LAA-stroke caused by intracranial atherosclerosis. In addition, AIP and TyG index were closely related to END only in patients with LAA-stroke caused by artery-to-artery embolism and branch atheromatous disease mechanisms.

CONCLUSIONS

We found that TG and TG-related parameters were associated with the occurrence of END in patients with acute LAA-stroke. This association appeared differently depending on the location or mechanism of the relevant vessel that caused LAA-stroke.

Differential Pattern of Circulating MicroRNA Expression in Patients with Intracranial Atherosclerosis

Background: Intracranial atherosclerosis (ICAS) is a major cause of ischemic stroke, yet fundamental studies regarding epigenetic regulation of ICAS are lacking. We hypothesized that, due to anatomical and/or functional differences, extracranial atherosclerosis is distinct from ICAS, which may explain the clinical variability as well. Methods: We chose a number of miRNAs involved in various steps of atherogenesis (namely, miR-712/205-5p/-3p, miR-106b-3p/-5p, miR-146a-3p/-5p, miR-100-3p/miR-5p, miR-200c-3p/-5p, miR-532-3p/-5p, and miR-126-3p/-5p) and examined their plasma levels in a cohort of patients with carotid stenosis > 50% (n = 35, mean age: 65 years, 54% male; 12 patients had ICAS). Results: A differential pattern of circulating miR expression was found in ICAS patients: there was an overexpression of miR-712/205-5p, miR-106b-5p, miR-146a-5p, miR-200c-5p, miR-532-3p, and miR-126-3p. The following miRs were underexpressed in intracranial atherosclerosis-miR-712/205-3p and miR-100-3p. These changes represent a plethora of atherogenic mechanisms: smooth muscle cell migration (miR-712/205, miR-532), foam cell formation (miR-106b, miR-146a), endothelial dysfunction (miR-200c), low-density lipoprotein-induced vascular damage (miR-100), and leukocyte recruitment (miR-126). In symptomatic ICAS patients, we observed a statistically significant upregulation of miR-712/205-3p and miR-146a-5p. Conclusions: Overall, the findings of our pilot study revealed several new and interesting associations: (1) intracranial atherosclerosis seems to have a different epigenetic profile (regarding circulating microRNA expression) than isolated extracranial vessel involvement; (2) ischemic stroke in ICAS may be potentiated by other pathophysiologic mechanisms than in extracranial-only atherosclerosis (ECAS). Certain miRs (e.g., miR-712/205) seem to have a larger impact on ICAS than on extracranial atherosclerosis; this may be potentially linked to difference between extra- and intracranial artery morphology and physiology, and/or may lead to the said differences. This underscores the importance of making a distinction in future epigenetic studies between ECAS and ICAS, as the mechanisms of atherogenesis are likely to vary.

Intracranial Atherosclerotic Stenosis

BACKGROUND

Ischemic stroke is a significant global health problem associated with mortality and disability. Intracranial atherosclerotic stenosis (ICAS) is a leading cause of stroke and contributes to recurrent stroke, especially in the Asian population. ICAS should be distinguished from extracranial atherosclerotic stenosis (ECAS) due to differences in pathophysiology. Understanding the mechanisms of ICAS is crucial for stroke prevention in the Asian population. Traditional vascular risk factors and the degree of the stenosis play an important role in predicting stroke occurrence.

SUMMARY

In East Asia, non-atherosclerotic vasculopathies are also often observed in ischemic stroke patients caused by large artery disease, highlighting the importance of identifying the specific etiologies of intracranial artery stenosis. Advances in diagnostic neuroimaging, such as high-resolution MRI (HR-MRI), can be helpful in distinguishing between them. For stroke prevention in patients with both asymptomatic and symptomatic ICAS, intensive management, including strict control of modifiable risk factors and appropriate antiplatelet therapies, is essential. There are no clear guidelines regarding the duration and combination of antiplatelet therapies. However, current recommendations suggest short-term dual antiplatelet therapies for 90 days to reduce the recurrence of stroke in symptomatic severe ICAS (70-99%). Cilostazol is also proposed as a good second-line treatment option, following clopidogrel, which remains the most widely used. In addition, endovascular or surgical interventions could be considered alternatives for a limited subset of symptomatic severe ICAS cases that are hemodynamically unstable.

KEY MESSAGES

The key messages are as follows: (1) ICAS is a major cause of ischemic stroke, especially in Asian populations. Its distinct pathophysiology, compared to ECAS, requires different treatment strategies for secondary prevention; (2) differentiation of intracranial artery stenosis etiology is essential, and HR-MRI would be a valuable diagnostic tool; (3) stroke prevention includes strict vascular risk factor control and the use of antiplatelet therapies, with short-term DAPT recommended for symptomatic severe ICAS; (4) cilostazol may serve as an effective second-line option for preventing ischemic stroke, while endovascular or surgical interventions may be limited to hemodynamically unstable cases.

BACKGROUND

Ischemic stroke is a significant global health problem associated with mortality and disability. Intracranial atherosclerotic stenosis (ICAS) is a leading cause of stroke and contributes to recurrent stroke, especially in the Asian population. ICAS should be distinguished from extracranial atherosclerotic stenosis (ECAS) due to differences in pathophysiology. Understanding the mechanisms of ICAS is crucial for stroke prevention in the Asian population. Traditional vascular risk factors and the degree of the stenosis play an important role in predicting stroke occurrence.

SUMMARY

In East Asia, non-atherosclerotic vasculopathies are also often observed in ischemic stroke patients caused by large artery disease, highlighting the importance of identifying the specific etiologies of intracranial artery stenosis. Advances in diagnostic neuroimaging, such as high-resolution MRI (HR-MRI), can be helpful in distinguishing between them. For stroke prevention in patients with both asymptomatic and symptomatic ICAS, intensive management, including strict control of modifiable risk factors and appropriate antiplatelet therapies, is essential. There are no clear guidelines regarding the duration and combination of antiplatelet therapies. However, current recommendations suggest short-term dual antiplatelet therapies for 90 days to reduce the recurrence of stroke in symptomatic severe ICAS (70-99%). Cilostazol is also proposed as a good second-line treatment option, following clopidogrel, which remains the most widely used. In addition, endovascular or surgical interventions could be considered alternatives for a limited subset of symptomatic severe ICAS cases that are hemodynamically unstable.

KEY MESSAGES

The key messages are as follows: (1) ICAS is a major cause of ischemic stroke, especially in Asian populations. Its distinct pathophysiology, compared to ECAS, requires different treatment strategies for secondary prevention; (2) differentiation of intracranial artery stenosis etiology is essential, and HR-MRI would be a valuable diagnostic tool; (3) stroke prevention includes strict vascular risk factor control and the use of antiplatelet therapies, with short-term DAPT recommended for symptomatic severe ICAS; (4) cilostazol may serve as an effective second-line option for preventing ischemic stroke, while endovascular or surgical interventions may be limited to hemodynamically unstable cases.

Impact of atherosclerotic etiology on technical and clinical outcomes of mechanical thrombectomy with a stent retriever: subanalysis of the Japan Trevo Registry

BACKGROUND

The safety and effectiveness of stent retriever use for patients with acute large vessel occlusion (LVO) due to intracranial atherosclerotic disease (ICAD) is not well established. We investigated the differences in clinical outcomes in patients with and without ICAD.

METHODS

We analyzed the Japan Trevo Registry, a nationwide registry which enrolled patients with acute LVO who underwent endovascular therapy (EVT) using the Trevo retriever alone or in combination with an aspiration catheter. We compared the technical and clinical outcomes of EVT between the ICAD and No-ICAD groups. The primary outcome was effective reperfusion and the secondary outcome was modified Rankin scale (mRS) score 0-2 at 90 days. Safety outcomes were worsening of neurologic symptoms within 24 hours, any intracranial hemorrhage within 24 hours, vessel dissection/vessel perforation related to using the Trevo retriever and mortality at 90 days.

RESULTS

A total of 835 patients (45 in the ICAD group and 790 in the No-ICAD group) were analyzed. In the ICAD group, more men (68.9% vs 50.8%, P=0.02) and a lower median National Institutes of Health Stroke Scale score at admission (11 vs 18, P<0.0001) were observed. The primary outcome was significantly more common in the No-ICAD group (92.5%) than in the ICAD group (80.0%) (adjusted odds ratio (aOR) 0.21, 95% CI 0.09 to 0.50). The proportion of patients with mRS score 0-2 at 90 days was significantly lower in the ICAD group (44.4% vs 42.4%, aOR 0.49, 95% CI 0.23 to 1.00, P=0.0496). Other secondary and safety outcomes were not significantly different between the two groups.

CONCLUSIONS

Patients with LVO with ICAD had a lower rate of effective reperfusion than those with No-ICAD.

Outcomes of Symptomatic Intracranial Large Artery Stenoses: A Prospective Cohort Study from the Asian Registry of Intracranial Atherosclerosis

INTRODUCTION

Intracranial large artery atherosclerosis (ICAS) is a common cause of stroke in Asia. Prior epidemiological publications on ICAS have largely been single-country reports. This collaborative study involving several Asian countries aims to investigate the characteristics and outcomes of patients with stroke attributable to ICAS.

METHODS

This is an international, multicenter, observational, prospective cohort study of patients admitted with acute ischemic stroke secondary to ICAS to stroke centers in six Asian countries. Stroke due to ICAS was diagnosed when there was a ≥50% intracranial large artery stenosis ipslateral to a non-lacunar infarct, without significant ipsilateral extracranial stenosis, cardiac cause or other mechanism found for the stroke. Data were collected on patient demographics, vascular risk factors, stroke location, and severity. Outcomes of interest were stroke recurrence and mortality at 12-month follow-up.

RESULTS

A total of 356 patients were recruited. Mean age was 62.7 ± 13.8 years, and 39.9% were females. Mean NIHSS on admission was 9 ± 8, with majority of patients having mild (39.3%) or moderate (37.9%) strokes. Stroke recurrence was 6.7% (95% CI: 4.4-9.9%) while mortality rate was 13.2% (95% CI: 9.9-17.2%) within 1 year. The risk of stroke recurrence was associated with increasing age (odds ratio [OR]: 1.04, 95% CI: 1-1.06, p = 0.05) and hypertension (OR: 3.23, 95% CI: 1.09-9.61, p = 0.035). Mortality was associated with age (OR: 1.05, 95% CI: 1.01-1.08, p = 0.006) and NIHSS (OR: 1.12, 95% CI: 1.07-1.17, p < 0.001).

CONCLUSIONS

This multicenter Asian study demonstrates a high risk of stroke recurrence and mortality among patients with acute stroke due to ICAS. They are associated with age (both), as well as hypertension (for recurrence) and NIHSS (for mortality). Better treatment modalities are needed to reduce the frequency of adverse outcomes in symptomatic ICAS.

Age-Related Association Between Circulating Inflammatory Indicators and Plaque Enhancement on High-Resolution Magnetic Resonance Imaging in Patients with Intracranial Atherosclerotic Stenosis

Background

Plaque enhancement is a non-specific marker of local inflammatory response, which may offer additional insights together with circulating inflammatory markers. Few studies have analyzed the association between intracranial atherosclerotic stenosis (ICAS) plaque enhancement and circulating inflammatory markers. Given the age-related variability in the progression of ICAS, this study aims to explore the association between the two across different age groups.

Methods

This retrospective study recruited 120 patients with ICAS-related ischemic events who had undergone high-resolution magnetic resonance imaging. Plaque enhancement index at the most stenosed site of the culprit vessel was calculated. Levels of circulating inflammatory indicators, including high-sensitivity C-reactive protein (hsCRP), lymphocyte-to-white blood cell ratio (LWR), systemic immune inflammation index (SII), platelet-to-lymphocyte ratio (PLR), lymphocyte-to-monocyte ratio (LMR), and neutrophil-to-lymphocyte ratio (NLR), were detected. General linear regression models were established to analyze the association between ICAS plaque enhancement index and circulating inflammatory indicators.

Results

In this study, hsCRP, but not other circulating inflammatory indicators, had a significant positive association with ICAS plaque enhancement index (β=0.219, 95% CI [0.036, 0.349], P=0.02). After multivariate adjustment, there was still a marginal correlation between hsCRP and the enhancement index (β=0.220, 95% CI [0.025, 0.362], P=0.05). The association was particularly significant in patients <60 years rather than those ≥60 years. For participants <60 years, hsCRP had the highest contribution to plaque enhancement interpretation.

Conclusion

ICAS plaque enhancement index was positively associated with hsCRP, particularly in participants aged <60 years. This may be helpful for understanding the significance of the enhancement index in clinical practice.

Healthy Dietary Patterns and Lower Atherosclerosis in High-Risk Individuals

Background

This study investigates associations between diet patterns and the risk of intracranial atherosclerosis (ICAD) in individuals with preexisting hypertension (HTN) or myocardial infarction (MI).

Method

676 autopsied participants (mean age at death =91.1±6.1, 71% women) of a longitudinal clinical neuropathological cohort study, with complete dietary and neuropathology data, were included. Diet scores were computed (median interval to death = 5.9 (3.0, 8.7 years). HTN and MI history was self-reported. Large vessel atherosclerosis was evaluated at the circle of Willis, and severity of intracranial atherosclerosis was assessed based on number of atherosclerotic plaques, extent of vessel involvement, and degree of vessel occlusion to create a 4-level grading system (0-3). All regression models were adjusted for age, sex, education, caloric intake, and APOE4.

Results

Of the 676 subjects, 361 (53%) had mild, 142 (21%) had moderate, and 29 (5%) had severe atherosclerosis. There was no direct relationship between diet and atherosclerosis. The relationship between ICAD and MI (OR = 1.38, 95% CI = 0.95, 2.00) showed a nonsignificant trend. HTN (OR = 1.598, 95% CI = 1.15, 2.18) was positively associated with intracranial atherosclerosis. The association of diet with intracranial atherosclerosis differed by history of MI (MIND (p=0.007), MedDiet (p=0.006)). The association between ICAD and the MIND diet also differed by whether HTN was reported (β=-0.212, SE= 0.111, p=0.055) as did the relationship between ICAD and the MedDiet (β = -0.077, SE= 0.035, p=0.029). In stratified analysis, among individuals with preexisting MI (N=130), those with a better diet had lower odds of intracranial atherosclerosis (MedDiet: OR = 0.88, 95% CI = 0.81, 0.96; MIND: OR = 0.69, 95% CI = 0.53, 0.90).

Conclusion

A healthy dietary pattern is associated with lower odds of severe intracranial large vessel atherosclerosis in high-risk older adults. In-vivo studies of dietary habits and brain health, specifically in those at high vascular risk are needed.

Edge-Type Hyperintense Intracranial Artery Plaque: A Potential MRI Biomarker of Stroke Recurrence

BACKGROUND

Identifying patients at high risk of stroke recurrence is important for stroke prevention and treatment.

PURPOSE

To explore the characteristics of T1 hyperintense plaques (HIP) and their relationship with stroke recurrence in patients with symptomatic intracranial atherosclerotic stenosis (sICAS).

STUDY TYPE

Retrospective.

POPULATION

One hundred fifty-seven patients with moderate-to-severe (≥50%) nonocclusive sICAS and MRI studies (42 females and 115 males, mean age 58.69 ± 10.68 years).

FIELD STRENGTH/SEQUENCE

3D higher-resolution black-blood T1-weighted fast-spin-echo sequence at 3.0 T.

ASSESSMENT

HIP (signal intensity [SI] of plaque-to-adjacent gray matter >1.0 on non-contrast T1-weighted images) and non-HIP plaques were identified. HIP plaques were categorized as edge type (high SI adjacent to lumen) and non-edge type (high SI within plaque). Clinical and imaging features of different plaque types were compared. Stroke recurrence was assessed through telephone or medical records at 3 and 6 months, and then once a year post-MRI. The relationship between edge type and non-edge types HIP with stroke recurrence was analyzed.

STATISTICAL TESTS

Student's t test, Mann-Whitney U-test, chi square test and Fisher's exact test to compare features between plaque types. Kaplan-Meier curves (with log-rank tests) and Cox proportional hazards regression to assess relationship between stroke recurrence and different plaque types. A two-tailed P-value of <0.05 was considered statistically significant.

RESULTS

Of 157 culprit lesions, 87 (55%) were HIPs (43 edge type, 44 non-edge type) and 70 (45%) were non-HIPs. Plaque thickness, area, and volume were significantly higher for HIPs than for non-HIPs. Among patients with HIPs, edge type was significantly more likely in the posterior circulation (53.5% vs. 27.3%), and had significantly higher plaque thickness, length, area, volume, plaque burden, and remodeling index than non-edge type. Edge-type HIP was significantly more common than non-edge HIP in patients with diabetes mellitus (51.2% vs. 29.5%) and dyslipidemia (79.1% vs. 54.5%). During median follow-up of 27 months, 33 patients experienced stroke recurrence. Recurrence was associated with edge-type HIP (adjusted hazard ratio = 2.83; 95% confidence interval: 1.40-5.69), both in the overall cohort (34.9% vs. 15.8%) and in patients with HIP (34.9% vs. 9.0%). Age ≥60 years and edge-type HIP had a significant interaction.

DATA CONCLUSIONS

Hyperintense plaque may be categorized as edge type or non-edge type. Edge-type HIP may be a potential MRI biomarker of stroke recurrence.

EVIDENCE LEVEL

3 TECHNICAL EFFICACY: Stage 2.

Stenting for symptomatic intracranial arterial stenosis with different qualifying arteries: a preplanned pooled individual patient data analysis

BACKGROUND

The efficacy of percutaneous transluminal angioplasty and stenting (PTAS) relative to medical management in treating symptomatic intracranial arterial stenosis (ICAS) varies based on the qualifying artery. This study aims to evaluate PTAS compared with medical therapy alone in cases of ICAS involving the internal carotid artery (ICA), middle cerebral artery (MCA), vertebral artery (VA) and basilar artery (BA).

METHODS

This study involves a thorough pooled analysis of individual patient data from two randomised controlled trials, evaluating the efficacy of PTAS in comparison to medical management for symptomatic ICAS with different qualifying arteries. The primary outcome was stroke or death within 30 days postenrolment, or stroke in the region of the qualifying artery beyond 30 days through 1 year. A methodology based on intention-to-treat was employed, and HR accompanied by 95% CIs were used to convey risk estimates.

RESULTS

The data of 809 individuals were collected from Stenting vs Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis trial and China Angioplasty and Stenting for Symptomatic Intracranial Severe Stenosis trial. Four hundred were designated for PTAS, while 409 were assigned to medical therapy alone. For the primary outcome, patients with symptomatic BA stenosis had a significantly higher risk of receiving PTAS compared with medical therapy (17.17% vs 7.77%; 9.40; HR, 2.38 (1.03 to 5.52); p=0.04). However, PTAS had no significant difference in patients with symptomatic ICA (26.67% vs 16.67%; HR, 1.68 (0.78 to 3.62); p=0.19), MCA (8.28% vs 9.79%; HR, 0.85 (0.42 to 1.74); p=0.66) and VA stenosis (9.52% vs 10.71%; HR, 0.91 (0.32 to 2.62); p=0.86) compared with medical therapy.

CONCLUSIONS

PTAS significantly increases the risk of both short-term and long-term stroke in patients with symptomatic BA stenosis. Without significant technological advancements to mitigate these risks, PTAS offers limited benefits. For symptomatic ICA, MCA and VA stenosis, PTAS provided no significant advantage.

Site-specific m6A-miR-494-3p, not unmethylated miR-494-3p, compromises blood brain barrier by targeting tight junction protein 1 in intracranial atherosclerosis

BACKGROUND AND PURPOSE

Intracranial atherosclerosis is one of the most common causes of ischaemic stroke. However, there is a substantial knowledge gap on the development of intracranial atherosclerosis. Intracranial arteries are characterized by an upregulation of tight junctions between endothelial cells, which control endothelial permeability. We investigated the role of N6-methyladenosine (m6A), a common RNA modification, on endothelial integrity, focusing on the pro-atherogenic microRNA miR-494-3p and tight junction proteins TJP1 and PECAM1.

EXPERIMENTAL APPROACH

We assessed the m6A landscape, along with the expression of miR-494-3p, TJP1 and PECAM1 in postmortem human vertebral arteries (VA), internal carotid arteries (ICA), and middle cerebral arteries (MCA) with various stages of intimal thickening and plaque formation. The interactions between m6A-modified miR-494-3p mimics, TJP1 and PECAM1, were investigated in vitro using primary human (brain) endothelial cells.

KEY RESULTS

Increased m6A expression was observed in the luminal lining of atherosclerosis-affected VAs, accompanied by reduced TJP1 and PECAM1, but not VE-cadherin, expression. Colocalization of m6A and miR-494-3p in the luminal lining of VA plaques was confirmed, indicating m6A methylation of miR-494-3p in intracranial atherosclerosis. Moreover, site-specific m6A-modification of miR-494-3p led to repression specifically of TJP1 protein expression at cell-cell junctions of brain microvascular endothelial cells, while unmodified miR-494-3p showed no effect.

CONCLUSIONS AND IMPLICATIONS

This study highlights increasing m6A levels during intracranial atherogenesis. Increases in m6A-miR-494-3p contribute to the observed decreased TJP1 expression in endothelial cell-cell junctions. This is likely to have a negative effect on endothelial integrity and may thus accelerate intracranial atherosclerosis progression.

Associations of Intracranial Artery Length and Branch Number on Time-of-Flight MRA With Cognitive Impairment in Hypertensive Older Males

BACKGROUND

Hypertension-induced impairment of the cerebral artery network contributes to cognitive impairment. Characterizing the structure and function of cerebral arteries may facilitate the understanding of hypertension-related pathological mechanisms and lead to the development of new indicators for cognitive impairment.

PURPOSE

To investigate the associations between morphological features of the intracranial arteries distal to the circle of Willis on time-of-flight MRA (TOF-MRA) and cognitive performance in a hypertensive cohort.

STUDY TYPE

Prospective observational study.

POPULATION

189 hypertensive older males (mean age 64.9 ± 7.2 years).

FIELD STRENGTH/SEQUENCE

TOF-MRA sequence with a 3D spoiled gradient echo readout and arterial spin labeling perfusion imaging sequence with a 3D stack-of-spirals fast spin echo readout at 3T.

ASSESSMENT

The intracranial arteries were segmented from TOF-MRA and the total length of distal arteries (TLoDA) and number of arterial branches (NoB) were calculated. The mean gray matter cerebral blood flow (GM-CBF) was extracted from arterial spin labeling perfusion imaging. The cognitive level was assessed with short-term and long-term delay-recall auditory verbal learning test (AVLT) scores, and with montreal cognitive assessment.

STATISTICAL TESTS

Univariable and multivariable linear regression were used to analyze the associations between TLoDA, NoB, GM-CBF and the cognitive assessment scores, with P < 0.05 indicating significance.

RESULTS

TLoDA (r = 0.314) and NoB (r = 0.346) were significantly correlated with GM-CBF. Multivariable linear regression analyses showed that TLoDA and NoB, but not GM-CBF (P = 0.272 and 0.141), were significantly associated with short-term and long-term delay-recall AVLT scores. These associations remained significant after adjusting for GM-CBF.

DATA CONCLUSION

The TLoDA and NoB of distal intracranial arteries on TOF-MRA are significantly associated with cognitive impairment in hypertensive subjects.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY: Stage 3.

Intracranial Atherosclerotic Disease and Incident Dementia: The ARIC Study (Atherosclerosis Risk in Communities)

BACKGROUND

Studies of the neurovascular contribution to dementia have largely focused on cerebral small vessel disease (CSVD), but the role of intracranial atherosclerotic disease (ICAD) remains unknown in the general population. The objective of this study was to determine the risk of incident dementia from ICAD after adjusting for CSVD and cardiovascular risk factors in a US community-based cohort.

METHODS

We acquired brain magnetic resonance imaging examinations from 2011 through 2013 in 1980 Black and White participants in the ARIC study (Atherosclerosis Risk in Communities), a prospective cohort conducted in 4 US communities. Magnetic resonance imaging examinations included high-resolution vessel wall magnetic resonance imaging and magnetic resonance angiography to identify ICAD. Of these participants, 1590 without dementia, without missing covariates, and with adequate magnetic resonance image quality were followed through 2019 for incident dementia. Associations between ICAD and incident dementia were assessed using Cox proportional hazard ratios adjusted for CSVD (characterized by white matter hyperintensities, lacunar infarctions, and microhemorrhages), APOE4 genotype (apolipoprotein E gene ε4), and cardiovascular risk factors.

RESULTS

The mean age (SD) of study participants was 77.4 (5.2) years. ICAD was detected in 34.6% of participants. After a median follow-up of 5.6 years, 286 participants developed dementia. Compared with participants without ICAD, the fully adjusted hazard ratios (95% CIs) for incident dementia in participants with any ICAD, with ICAD only causing stenosis ≤50%, and with ICAD causing stenosis >50% in ≥1 vessel were 1.57 (1.17-2.11), 1.41 (1.02-1.95), and 1.94 (1.32-2.84), respectively. ICAD was associated with dementia even among participants with low white matter hyperintensities burden, a marker of CSVD.

CONCLUSIONS

ICAD was associated with an increased risk of incident dementia, independent of CSVD, APOE4 genotype, and cardiovascular risk factors. The increased risk of dementia was evident even among participants with low CSVD burden, a group less likely to be affected by vascular dementia, and in participants with ICAD causing only low-grade stenosis. Our results suggest that ICAD may partially mediate the effect that cardiovascular risk factors have on the brain leading to dementia. Both ICAD and CSVD must be considered to understand the vascular contributions to cognitive decline.

Effects of intracranial artery stenosis of anterior circulation on cognition-A CT perfusion-based study

BACKGROUND

Intracranial atherosclerotic stenosis (ICAS) is one of the most important independent risk factors for stroke that is closely related to the occurrence of cognitive impairment. The relationship between ICAS and vascular cognitive impairment (VCI) remains unclear. Cerebral hemodynamic changes are one of the main causes of cognitive impairment. Computed tomographic perfusion (CTP) imaging can quantitatively analyze cerebral blood perfusion and quantify cerebral hemodynamic changes. Previous research on the relationship between hypoperfusion induced by ICAS and cognitive impairment, as well as its underlying mechanisms, remains relatively insufficient. This study is dedicated to elucidating the characteristics and potential mechanisms of cognitive impairment in ICAS patients with abnormal perfusion, utilizing CTP imaging as our primary investigative tool.

METHODS

This study recruited 82 patients who suffer from non-disabling ischemic stroke (IS group) and 28 healthy controls. All participants underwent comprehensive neuropsychological assessments both collectively and individually, in addition to CTP imaging. Within the patient group, we further categorized individuals into two subgroups: the ischemic penumbra group (IP, N = 28) and the benign oligemia group (BO, N = 54), based on CTP parameters-Tmax. The correlations between cognitive function and abnormal perfusion were explored.

RESULTS

The cognitive function, including the overall cognitive, memory, attention, executive functions, and language, was significantly impaired in the IS group compared with that in the control group. Further, there are statistical differences in the stroop color-word test-dot (Stroop-D) and Montreal Cognitive Assessment (MoCA) sub-items (memory + language) between the BO and IP groups. In the BO group, the score of Stroop-D is lower, and the MoCA sub-items are higher than the IP group. There is no correlation between CTP parameters and cognitive function.

CONCLUSION

Cognitive function is significantly impaired in patients with ICAS, which is related to cerebral perfusion. Executive, memory, and language function were better preserved in ICAS patients without IP. Hence, this study posits that managing hypoperfusion induced by ICAS may play a pivotal role in the development of VCI.

Lipid on stroke in intracranial artery atherosclerotic stenosis: a mediation role of glucose

Objective

Expanding on previous investigations, this study aims to elucidate the role of lipid metabolism disorders in the development of intracranial atherosclerotic stenosis (ICAS) and the determination of stroke risk. The primary objective is to explore the connections between lipid parameters and acute ischemic stroke (AIS), while also examining the potential mediating influence of fasting glucose levels.

Methods

Retrospectively, we collected data from symptomatic ICAS patients at the First Affiliated Hospital of Soochow University, including their baseline information such as medical histories and admission blood biochemical parameters. Stenotic conditions were evaluated using magnetic resonance imaging, computed tomography angiography, or digital subtraction angiography. The associations between lipid parameters and AIS risks were investigated via multivariate logistic regression analysis.

Results

A total of 1103 patients with symptomatic ICAS were recruited, among whom 441 (40.0%) suffered new ischemic events during hospitalization. After adjusting for confounding factors, the RCS curves exhibited a dose-response relationship between the atherogenic index of plasma (AIP), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and AIS. Further multivariate analysis revealed significant associations between these parameters and AIS. Furthermore, mediation analysis indicated that fasting blood glucose (FBG) acted as a mediator in the association between lipid parameters (AIP, TC, and TG) and AIS.

Conclusion

Higher lipid parameters in ICAS patients, particularly AIP, TC, and TG, were associated with an increased AIS risk. Additionally, FBG may mediate stroke risk in ICAS patients, highlighting the need for further exploration of underlying mechanisms.

The guardian of intracranial vessels: Why the pericyte?

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

Hemodynamic Impairment of Blood Pressure and Stroke Mechanisms in Symptomatic Intracranial Atherosclerotic Stenosis

BACKGROUND

Hemodynamic impairment of blood pressure may play a crucial role in determining the mechanisms of stroke in symptomatic intracranial atherosclerotic stenosis). We aimed to elucidate this issue and assess the impacts of modifications to blood pressure on hemodynamic impairment.

METHODS

From the Third China National Stroke Registry III, computed fluid dynamics modeling was performed using the Newton-Krylov-Schwarz method in 339 patients with symptomatic intracranial atherosclerotic stenosis during 2015 to 2018. The major exposures were translesional systolic blood pressure (SBP) drop and poststenotic mean arterial pressure (MAP), and the major study outcomes were cortex-involved infarcts and borderzone-involved infarcts, respectively. Multivariate logistic regression models and the bootstrap resampling method were utilized, adjusting for demographics and medical histories.

RESULTS

In all, 184 (54.3%) cortex-involved infarcts and 70 (20.6%) borderzone-involved infarcts were identified. In multivariate logistic model, the upper quartile of SBP drop correlated with increased cortex-involved infarcts (odds ratio, 1.92 [95% CI, 1.03-3.57]; bootstrap analysis odds ratio, 2.07 [95% CI, 1.09-3.93]), and the lower quartile of poststenotic MAP may correlate with increased borderzone-involved infarcts (odds ratio, 2.07 [95% CI, 0.95-4.51]; bootstrap analysis odds ratio, 2.38 [95% CI, 1.04-5.45]). Restricted cubic spline analysis revealed a consistent upward trajectory of the relationship between translesional SBP drop and cortex-involved infarcts, while a downward trajectory between poststenotic MAP and borderzone-involved infarcts. SBP drop correlated with poststenotic MAP negatively (rs=-0.765; P<0.001). In generating hemodynamic impairment, simulating blood pressure modifications suggested that ensuring adequate blood pressure to maintain sufficient poststenotic MAP appears preferable to the reverse approach, due to the prolonged plateau period in the association between the translesional SBP drop and cortex-involved infarcts and the relatively short plateau period characterizing the correlation between poststenotic MAP and borderzone-involved infarcts.

CONCLUSIONS

This research elucidates the role of hemodynamic impairment of blood pressure in symptomatic intracranial atherosclerotic stenosis-related stroke mechanisms, underscoring the necessity to conduct hemodynamic assessments when managing blood pressure in symptomatic intracranial atherosclerotic stenosis.

Differential distribution of plasma apoA-I and apoB levels and clinical significance of apoB/apoA-I ratio in ischemic stroke subtypes

Background and purpose

Ischemic stroke (IS) is classified into clinical subtypes and likely influenced by various lipid components. Nevertheless, the roles of apolipoprotein A-I (apoA-I), apolipoprotein B (apoB), and apoB/apoA-I ratio in different IS subtypes remain underexplored. This study aimed to investigate the differential distribution of plasma apoA-I and apoB levels among IS subtypes and to evaluate the predictive value of the apoB/apoA-I ratio in assessing IS subtypes and disease severity.

Methods

In this study, 406 IS patients were categorized into three IS-subtypes based on clinical manifestations and imaging assessment, including intracranial atherosclerosis-related IS patients (ICAS, n = 193), extracranial atherosclerosis-related IS patients (ECAS, n = 111), and small artery occlusion-related IS patients (SAO, n = 102). Plasma apoA-I and apoB levels were measured upon hospital admission. Random forest (RF) models were performed to assess predictive values of these apolipoproteins apoB, apoA-I and their ratio in assessing IS subtype stratification and disease severity.

Results

Serum apoA-I levels were significantly lower in ICAS compared to ECAS and SAO patients (p < 0.0001), while apoB levels were higher in ICAS patients (p < 0.0001). The apoB/apoA-I ratio was significantly higher in ICAS compared to ECAS and SAO patients (p < 0.0001). Correlation analyses found a significant correlation between the apoB/apoA-I ratio and conventional lipid components. Additionally, RF models and plots of variable importance and distribution of minimal depth revealed that the apoB/apoA-I ratio played the most influential predictor in predicting IS subtypes and stenosis severity.

Conclusion

Our study shows the differential distribution of apoA-I and apoB IS subtypes and reveals the significance of the apoB/apoA-I ratio in assessing IS subtypes and arterial stenosis severity. Further studies are warranted to validate these findings and enhance their clinical applicability.

Moyamoya Vasculopathy and Moyamoya-Related Systemic Vasculopathy: A Review With Histopathological and Genetic Viewpoints

Systemic vasculopathy has occasionally been reported in cases of moyamoya disease (MMD). Since the pathological relationship between moyamoya vasculopathy (MMV) and moyamoya-related systemic vasculopathy (MMRSV) remains unclear, it was examined herein by a review of histopathologic studies in consideration of clinicopathological and genetic viewpoints. Although luminal stenosis was a common finding in MMV and MMRSV, histopathologic findings of vascular remodeling markedly differed. MMV showed intimal hyperplasia, marked medial atrophy, and redundant tortuosity of the internal elastic lamina, with outer diameter narrowing called negative remodeling. MMRSV showed hyperplasia, mainly in the intima and sometimes in the media, with disrupted stratification of the internal elastic lamina. Systemic vasculopathy has also been observed in patients with non-MMD carrying the RNF213 (ring finger protein 213) mutation, leading to the concept of RNF213 vasculopathy. RNF213 vasculopathy in patients with non-MMD was histopathologically similar to MMRSV. Cases of MMRSV have sometimes been diagnosed with fibromuscular dysplasia. Fibromuscular dysplasia is similar to MMD not only in the histopathologic findings of MMRSV but also from clinicopathological and genetic viewpoints. The significant histopathologic difference between MMV and MMRSV may be attributed to a difference in the original vascular wall structure and its resistance to pathological stress between the intracranial and systemic arteries. To understand the pathogeneses of MMD and MMRSV, a broader perspective that includes RNF213 vasculopathy and fibromuscular dysplasia as well as an examination of the 2- or multiple-hit theory consisting of genetic factors, vascular structural conditions, and vascular environmental factors, such as blood immune cells and hemodynamics, are needed.

Recent Translational Research Models of Intracranial Atherosclerotic Disease

Intracranial atherosclerotic disease (ICAD) is a leading cause of ischemic stroke worldwide. However, research on the pathophysiology of ICAD is scarce due to the relative inaccessibility of histology samples and the lack of comprehensive experimental models. As a result, much of the current understanding of ICAD relies on research on extracranial atherosclerosis. This approach is problematic as intracranial and extracranial arteries are anatomically, structurally, physiologically, and metabolically distinct, indicating that intracranial and extracranial atherosclerosis likely develop through different biologic pathways. The current standard of care for ICAD treatment relies predominantly on therapeutics developed to treat extracranial atherosclerosis and is insufficient given the alarmingly high risk of stroke. To provide a definitive treatment for the disease, a deeper understanding of the pathophysiology underlying ICAD is specifically required. True mechanistic understanding of disease pathogenesis is only possible using robust experimental models. In this review, we aim to identify the advantages and limitations of the existing in vivo and in vitro models of ICAD and basic atherosclerotic processes, which may be used to inform better models of ICAD in the future and drive new therapeutic strategies to reduce stroke risk.

Triglyceride-Related Parameters and Symptomatic Atherosclerotic Lesions in Patients With Ischemic Stroke

Objective

Recently, evidence has suggested that the pathophysiology and risk factors of intracranial atherosclerosis (ICAS) differs from those of extracranial atherosclerosis (ECAS). In addition, novel parameters reflecting metabolic conditions, such as insulin resistance or atherogenic dyslipidemia, based on triglycerides (TG) and other biomarkers, have emerged. In this study, we evaluated the association between TG-related parameters and symptomatic cerebral atherosclerosis in patients with acute ischemic stroke resulting from large artery atherosclerosis (LAA).

Methods

We assessed consecutive acute LAA-stroke patients between January 2010 and December 2020. Based on the radiological findings, we classified the relevant symptomatic arteries that caused the index stroke into LAA-ICAS and LAA-ECAS. As TG-related parameters, the atherogenic index of plasma (AIP) and TG-glucose (TyG) index were calculated according to the following formulas: AIP = log10 (TG Level/High-density Lipoprotein Cholesterol Level), TyG Index = Ln (TG Level × Glucose Level/2).

Results

A total of 519 patients with LAA-stroke were evaluated. In multivariable logistic regression analysis to identify predictors of LAA-ICAS, AIP was significantly associated with LAA-ICAS (adjusted odds ratio [aOR], 3.60; 95% confidence interval [CI], 1.60-8.06). TyG index also showed a statistically significant relationship with LAA-ICAS (aOR, 1.60; 95% CI, 1.11-2.32). However, TG per se did not show a statistical association with LAA-ECAS.

Conclusion

TG-related parameters were more closely associated with stroke by ICAS than by ECAS. The metabolic conditions reflected by the AIP or TyG index, rather than hypertriglyceridemia itself, may play a greater role in determining the relevant vessel causally involved in a stroke.

A bibliometric analysis of the 100 most-cited clinical articles in the research of intracranial artery stenosis and intracranial atherosclerosis

Background

Intracranial arterial stenosis (ICAS), caused by intracranial atherosclerosis, is one of the major causes of ischemic stroke. This study identified the top 100 most-cited publications on ICAS through a bibliometric analysis.

Methods

Two independent authors conducted a search in the Web of Science database for clinical articles on ICAS published between 1993 and 2022. The top 100 most-cited articles were then extracted. For each article, the analysis covered the title, author, country of origin/affiliation, journal, total number of citations, number of citations per year, and type of study.

Results

The top 100 most-cited papers in the ICAS were authored by 565 authors from 12 countries and published in 29 journals. In terms of the 5-year trend, the largest number of papers were published between 2003 and 2007 (n = 31). The median number of citations for the 100 papers was 161 (range 109-1,115). The journal with the highest proportion of the 100 most published articles was Stroke, accounting for 41% of articles and 37% of the citations. According to country of origin, the United States of America accounted for the largest number of articles, followed by China, Japan, and South Korea, with these four countries together accounting for 81% of the total number of articles and 88% of the citations. Trends in the past five years included the use of terms such as acute ischemic stroke and mechanical thrombectomy.

Conclusion

The findings of this study provide novel insight into this field and will facilitate future research endeavors.

Oral anticoagulants: A plausible new treatment for Alzheimer's disease?

Alzheimer's disease (AD) and cardiovascular disease (CVD) are strongly associated. Both are multifactorial disorders with long asymptomatic phases and similar risk factors. Indeed, CVD signatures such as cerebral microbleeds, micro-infarcts, atherosclerosis, cerebral amyloid angiopathy and a procoagulant state are highly associated with AD. However, AD and CVD co-development and the molecular mechanisms underlying such associations are not understood. Here, we review the evidence regarding the vascular component of AD and clinical studies using anticoagulants that specifically evaluated the development of AD and other dementias. Most studies reported a markedly decreased incidence of composite dementia in anticoagulated patients with atrial fibrillation, with the highest benefit for direct oral anticoagulants. However, sub-analyses by differential dementia diagnosis were scarce and inconclusive. We finally discuss whether anticoagulation could be a plausible preventive/therapeutic approach for AD and, if so, which would be the best drug and strategy to maximize clinical benefit and minimize potential risks. LINKED ARTICLES: This article is part of a themed issue From Alzheimer's Disease to Vascular Dementia: Different Roads Leading to Cognitive Decline. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v181.6/issuetoc.

Alcohol Consumption and Cerebral Small- and Large-Vessel Diseases: A Mendelian Randomization Analysis

AIMS

It remains inconclusive regarding alcohol intake and stroke risk because determining risk factors depends on the specific pathogenesis of stroke. We used the variant rs671 in the aldehyde dehydrogenase 2 gene (ALDH2) as an instrument to investigate the causal role of alcohol intake in cerebral small- and large-vessel diseases.

METHODS

We studied 682 men (mean age, 70.0 years), without stroke, in a cross-sectional Mendelian randomization analysis. We assessed small-vessel diseases (SVDs), which comprised lacunar infarcts, white matter hyperintensities (WMHs), and cerebral microbleeds, and large intracranial artery stenosis (ICAS) on brain magnetic resonance imaging.

RESULTS

The median (25%tiles, 75%tiles) alcohol consumption by ALDH2-rs671 inactive A allele (n=313 [45.9%]) and non-A allele (n=369 [54.1%]) carriers was 3.5 (0.0, 16.0) and 32.0 (12.9, 50.0) g/day, respectively. Non-A allele carriers had higher prevalent hypertension and lower low-density lipoprotein cholesterol concentrations than A allele carriers. In age-adjusted ordinal logistic regression for graded burden, odds ratios (95% confidence intervals) for total SVDs, lacunar infarcts, WMHs, cerebral microbleeds, and ICAS in non-Aallele carriers were 1.46 (1.09-1.94), 1.41 (0.95-2.08), 1.39 (1.05-1.85), 1.69 (1.06-2.69), and 0.70 (0.50-0.98), respectively, compared with A allele carriers. These associations attenuated to statistical non-significance after considering covariates and amount of alcohol intake.

CONCLUSIONS

Our findings suggest a positive association of alcohol consumption with risk of cerebral SVDs and its inverse association with risk of large-vessel disease through intermediaries, such as hypertension or low-density lipoprotein cholesterol. These findings provide insight into potential causal mechanisms linking alcohol consumption with stroke risk.

Emerging Concept of Intracranial Arterial Diseases: The Role of High Resolution Vessel Wall MRI

Intracranial arterial disease (ICAD) is a heterogeneous condition characterized by distinct pathologies, including atherosclerosis. Advances in magnetic resonance technology have enabled the visualization of intracranial arteries using high-resolution vessel wall imaging (HR-VWI). This review summarizes the anatomical, embryological, and histological differences between the intracranial and extracranial arteries. Next, we review the heterogeneous pathophysiology of ICAD, including atherosclerosis, moyamoya or RNF213 spectrum disease, intracranial dissection, and vasculitis. We also discuss how advances in HR-VWI can be used to differentiate ICAD etiologies. We emphasize that one should consider clinical presentation and timing of imaging in the absence of pathology-radiology correlation data. Future research should focus on understanding the temporal profile of HR-VWI findings and developing quantitative interpretative approaches to improve the decision-making and management of ICAD.

Molecular biomarkers for vascular cognitive impairment and dementia

As disease-specific interventions for dementia are being developed, the ability to identify the underlying pathology and dementia subtypes is increasingly important. Vascular cognitive impairment and dementia (VCID) is the second most common cause of dementia after Alzheimer disease, but progress in identifying molecular biomarkers for accurate diagnosis of VCID has been relatively limited. In this Review, we examine the roles of large and small vessel disease in VCID, considering the underlying pathophysiological processes that lead to vascular brain injury, including atherosclerosis, arteriolosclerosis, ischaemic injury, haemorrhage, hypoperfusion, endothelial dysfunction, blood-brain barrier breakdown, inflammation, oxidative stress, hypoxia, and neuronal and glial degeneration. We consider the key molecules in these processes, including proteins and peptides, metabolites, lipids and circulating RNA, and consider their potential as molecular biomarkers alone and in combination. We also discuss the challenges in translating the promise of these biomarkers into clinical application.

Association of change in fat and lean mass with incident cardiovascular events for women in midlife and beyond: A prospective study using dual-energy x-ray absorptiometry (DXA)

OBJECTIVE

To determine whether changes in fat and lean mass over time, quantified using dual-energy x-ray absorptiometry (DXA), are related to incident cardiovascular events. Previous studies using surrogate anthropometric methods have had inconsistent findings.

STUDY DESIGN

Prospective, longitudinal observational study of women aged 40 to 80 randomly selected from the electoral roll and stratified into decades: 40-49, 50-59, 60-69 and 70-79 years.

MAIN OUTCOME MEASURES

Changes in anthropometric measurements (body mass index and waist-to-hip ratio) and DXA-quantified fat mass and lean mass between the first and fifth years of the study. Incident cardiovascular events recorded from the sixth to the 12th year.

RESULTS

In total 449 participants (87.9 %) were analyzed. A 10 % or greater decrease in total fat mass index was associated with a 67 % lower likelihood of any cardiovascular event (OR = 0.33, 95%CI 0.15-0.71); no association was observed for an increase. A 10 % or greater decrease in abdominal fat mass index was associated with a 62 % lower likelihood of incident stroke (OR = 0.38, 95%CI 0.16-0.91); no association was observed for an increase. A 10 % or greater decrease in appendicular lean mass index resulted in increased odds ratio of 2.91 for incident peripheral artery events (OR = 2.91, 95%CI 1.18-7.20).

CONCLUSIONS

Reducing fat mass for women in midlife and beyond may decrease the risk of cardiovascular events. An increase in fat mass may not contribute to additional cardiovascular events. A reduction in limb muscle mass may provide an independent marker for cardiometabolic risk and peripheral artery disease. No independent association was found using anthropometric measurements and incident cardiovascular events.

Neuropathologic evaluation of cerebrovascular disease in patients with rheumatoid arthritis

OBJECTIVES

Active RA has been associated with an increased risk of both cardiovascular and peripheral vascular disease. We aimed to compare cerebrovascular changes in patients with and without RA, both with and without a neuropathologic diagnosis of neurodegenerative disease.

METHODS

Patients with RA (n = 32) who died and underwent autopsy between 1994 and 2021 were matched to non-RA controls (n = 32) on age, sex and level of neurodegenerative proteinopathy. Routine neuropathologic examination was performed at the time of autopsy. Cerebrovascular disease severity was evaluated using modified Kalaria and Strozyk scales. Clinical dementia diagnoses were manually collected from patients' medical records.

RESULTS

Prior to death, 15 (47%) RA patients and 14 (44%) controls were diagnosed with dementia; 9 patients in each group (60% and 64%, respectively) had Alzheimer's disease. The prevalence of cerebral amyloid angiopathy, microinfarcts, infarcts or strokes was found to be similar between groups. Patients with RA were more likely to have more severe vascular changes in the basal ganglia by Kalaria scale (P = 0.04), but not in other brain areas. There were no significant differences in the presence of large infarcts, lacunar infarcts or leukoencephalopathy by Strozyk scale. Among patients with RA and no clinical diagnosis of dementia, the majority had mild-moderate cerebrovascular abnormalities, and a subset of patients had Alzheimer's disease neuropathologic changes.

CONCLUSION

In this small series of autopsies, patients with and without RA had largely similar cerebrovascular pathology when controlling for neurodegenerative proteinopathies, although patients with RA exhibited more pronounced cerebrovascular disease in the basal ganglia.

Vessel Wall Imaging of Intracranial Arteries: Fundamentals and Clinical Applications

With the increasing use of 3-tesla MRI scanners and the development of applicable sequences, it has become possible to achieve high-resolution, good contrast imaging, which has enabled the imaging of the walls of small-diameter intracranial arteries. In recent years, the usefulness of vessel wall imaging has been reported for numerous intracranial arterial diseases, such as for the detection of vulnerable plaque in atherosclerosis, diagnosis of cerebral arterial dissection, prediction of the rupture of cerebral aneurysms, and status of moyamoya disease and cerebral vasculitis. In this review, we introduce the histological characteristics of the intracranial artery, discuss intracranial vessel wall imaging methods, and review the findings of vessel wall imaging for various major intracranial arterial diseases.

Impact on Endovascular Thrombectomy for Acute Ischemic Stroke of Aortic Arch Calcification on Chest X-ray

BACKGROUND

Vascular conditions can affect the recanalization rates after endovascular thrombectomy (EVT) for acute ischemic stroke (AIS). Chest radiography can assess the conditions of the aortic arch based on the presence or absence of aortic arch calcification (AoAC). The aim of this study was to investigate the relationship between AoAC on chest radiography and first-pass successful recanalization (modified thrombolysis in cerebral infarction 2b/3 after the first-pass).

METHODS

We compared the rate of first-pass successful recanalization between patients with and without AoAC. A total of 193 patients with anterior circulation occlusion who underwent EVT between January 2017 and December 2021 were included.

RESULTS

AoAC was observed in 80 (41.5%) patients. Patients with AoAC were older (74.5 ± 7.78 vs. 63.9 ± 12.4 years, p < 0.001), had more EVT attempts (3.04 ± 1.95 vs. 2.01 ± 1.34 times, p < 0.001), and a longer procedural time (71.7 ± 31.2 vs. 48.7 ± 23.1 min, p < 0.001) than those without AoAC. Moreover, Patients with AoAC showed a lower incidence of first-pass successful recanalization (18.8% vs. 47.8%, p < 0.001) and a higher incidence of postprocedural hemorrhage (45.0% vs. 27.7%, p = 0.015) than those without AoAC. On multivariate analysis, AoAC was independently associated with first-pass successful recanalization (odds ratio: 0.239 [0.121-0.475], p < 0.001).

CONCLUSIONS

AoAC on chest radiography can be used as a preoperative predictor of successful first-pass recanalization in patients undergoing EVT for AIS.

Stent reconstruction in intracranial atherosclerotic disease related acute ischemic stroke results in high revascularization rates

OBJECTIVES

Intracranial atherosclerotic disease (ICAD) is a major cause of large vessel occlusion (LVO) in acute ischemic stroke (AIS). Our study aimed to analyze the effect of percutaneous transluminal angioplasty and stenting (PTAS) in patients with ICAD undergoing rescue treatment in terms of functional outcome and mortality rate at 90 days and compare the results to LVO with thromboembolic origins.

MATERIALS AND METHODS

A retrospective review of a mechanical thrombectomy (MT) single center database from 01/2019 to 09/2021 was carried out using chart review and angiogram analysis. From 469 acute stroke patients, 361 patients were enroled in the study, of whom twenty-four (6.6%) were diagnosed with underlying ICAD and treated with angioplasty and stent reconstruction (PTAS) with a standardized medication protocol. Successful reperfusion, peri-procedural complications, and functional independence at 90 days were collected as outcomes.

RESULTS

There was no difference in age or admission National Institutes of Health Stroke Scale (NIHSS). Onset to groin puncture (median 460 vs 277 min, P = 0.019) was significantly longer in the ICAD group. The procedure time (median 73 vs 60 min, P = 0.137) did not differ. Successful reperfusion was achieved in 95.8% of ICAD and 91.1% of the remaining patients (P = 0.445). Functional independence (mRS ≤ 2) at 90 days was achieved in 45.8% (11/24) and 42.7% (144/337, (P = 0.767)). The mortality rates (mRS 6) at 90 days were similar (29.2% vs 29.4% (P = 0.983)).

CONCLUSION

Despite significantly longer treatment delays, the outcome and revascularization rates of ICAD patients were similar to the thromboembolic cohort. Our proposed protocol of PTAS and medication protocol in ICAD was effective with a similar safety profile as MT in general.

Subintimal recanalization for non-acute occlusion of intracranial vertebral artery in an emergency endovascular procedure: A case report

BACKGROUND

Endovascular recanalization of non-acute intracranial artery occlusion is technically difficult, particularly when the microwire enters the subintima. Although the subintimal tracking and re-entry technique has been well established in the endovascular treatment of coronary artery occlusion, there is limited experience with its use in intracranial occlusion due to anatomical variations and a lack of dedicated devices.

CASE SUMMARY

A 74-year-old man was admitted to the hospital two days after experiencing acute weakness in both lower extremities, poor speech, and dizziness. After admission, imaging revealed acute ischemic stroke and non-acute occlusion of bilateral intracranial vertebral arteries (ICVAs). On the fourth day of admission, the patient's condition deteriorated and an emergency endovascular recanalization of the left ICVA was performed. During this procedure, a microwire was advanced in the subintima of the vessel wall and successfully reentered the distal true lumen. Two stents were implanted in the subintima. The patient's Modified Rankin Scale was 1 at three months postoperatively.

CONCLUSION

We present a technical case of subintimal recanalization for non-acute ICVA occlusion in an emergency endovascular procedure. However, we emphasize the necessity for caution when applying the subintimal tracking approach in intracranial occlusion due to the significant dangers involved.

Sex difference in cerebral atherosclerotic stenosis in Chinese asymptomatic subjects

BACKGROUND AND PURPOSE

Sex difference in cerebral atherosclerosis has been noted in previous studies, but the precise characteristics remain incompletely elucidated. This study aims to identify the sex difference in patients with asymptomatic cerebrovascular stenosis.

MATERIALS AND METHODS

The image and clinical data of 1305 consecutive patients who had head and neck computed tomography angiography (CTA) were collected. Fifty hundred and seventy-three patients (287 males) with asymptomatic atherosclerotic stenosis in cerebral arteries were finally included. The stenosis number, distribution, severity and their changes with age were analyzed and compared between males and females. Simple linear regression was used to assess the change in lesions with age.

RESULTS

A total of 2097 stenoses were identified in 573 patients, males had more stenoses than females (3 [2, 5] vs 3 [2, 4], p=0.015). The number of stenoses in extracranial arteries was much higher in males (p = 0.001). Females had higher percentage of stenosis in anterior (89.6% vs 85.9%, p = 0.012) and intracranial arteries (63.3% vs 57.1%, p = 0.004) than males. Males had higher percentage of moderate-severe stenosis (5.1% vs 3.2%, p = 0.026). Age (OR = 1.67; 95% CI 1.24-2.25; p < 0.001) and hypertension (OR = 2.53; 95% CI 1.24-5.15; p = 0.01) were associated with moderate-severe stenosis. In patients over 50 years old, the number of stenoses increased by 1.03 per 10 years (p < 0.001), with 0.72 more stenoses in males (p = 0.003).

CONCLUSIONS

Cerebral atherosclerotic stenosis was different between sexes regarding the distribution, severity and the change pattern with age, which underline the sex specific management in patients with cerebral atherosclerosis.

Soluble and insoluble protein aggregates, endoplasmic reticulum stress, and vascular dysfunction in Alzheimer's disease and cardiovascular diseases

Dementia refers to a particular group of symptoms characterized by difficulties with memory, language, problem-solving, and other thinking skills that affect a person's ability to perform everyday activities. Alzheimer's disease (AD) is the most common form of dementia, affecting about 6.2 million Americans aged 65 years and older. Likewise, cardiovascular diseases (CVDs) are a major cause of disability and premature death, impacting 126.9 million adults in the USA, a number that increases with age. Consequently, CVDs and cardiovascular risk factors are associated with an increased risk of AD and cognitive impairment. They share important age-related cardiometabolic and lifestyle risk factors, that make them among the leading causes of death. Additionally, there are several premises and hypotheses about the mechanisms underlying the association between AD and CVD. Although AD and CVD may be considered deleterious to health, the study of their combination constitutes a clinical challenge, and investigations to understand the mechanistic pathways for the cause-effect and/or shared pathology between these two disease constellations remains an active area of research. AD pathology is propagated by the amyloid β (Aβ) peptides. These peptides give rise to small, toxic, and soluble Aβ oligomers (SPOs) that are nonfibrillar, and it is their levels that show a robust correlation with the extent of cognitive impairment. This review will elucidate the interplay between the effects of accumulating SPOs in AD and CVDs, the resulting ER stress response, and their role in vascular dysfunction. We will also address the potential underlying mechanisms, including the possibility that SPOs are among the causes of vascular injury in CVD associated with cognitive decline. By revealing common mechanistic underpinnings of AD and CVD, we hope that novel experimental therapeutics can be designed to reduce the burden of these devastating diseases. Graphical abstract Alzheimer's disease (AD) pathology leads to the release of Aβ peptides, and their accumulation in the peripheral organs has varying effects on various components of the cardiovascular system including endoplasmic reticulum (ER) stress and vascular damage. Image created with BioRender.com.

Prevalence and Clinico-Radiologic Spectrum of Intracranial Atherosclerotic Disease-Related Stroke: An Observation from a Single Center in Saudi Arabia

BACKGROUND

Intracranial atherosclerotic disease (ICAD) is an important etiologic subtype of acute ischemic stroke (AIS). However, little direct evidence is available regarding ICAD-related stroke in Saudi Arabia (SA). This study aimed to identify the prevalence and describe the clinico-radiological spectrum of ICAD-related AIS in a SA cohort.

METHODS

This was a hospital-based retrospective study enrolling patients with ICAD-related AIS between 2017 and 2020. The electronic charts were reviewed. The mechanisms of stroke were identified as artery-to-artery embolization (AAE), in situ thrombotic occlusion, hypoperfusion, or perforator branch occlusion. Pearson's χ 2 test was performed to calculate the P values to establish the statistical significance of factors that could correlate with the mechanisms of stroke and functional outcome.

RESULTS

ICAD was found in 133 of AIS comprising 26% of total. Data from all patients were reviewed. Left ICA (25%) was the most frequently affected vessel. Territorial pattern (63.9%) was the most common infarct pattern, and AAE (44.3%) was the most common underlying mechanism. Perforator branch occlusion was more prevalent in women than in men. Malignant and hemorrhagic transformation ( P =0.00) were more prevalent in the AAE group. Left-sided vascular involvement was statistically associated with unfavorable outcomes than the right ( P =0.019).

CONCLUSIONS

The prevalence of ICAD in our cohort from Western Asia did not differ from that in Southern Asia. ICA involvement was observed more frequently than previously reported. Further research from SA is required to better understand ICAD-related strokes in this region.

Differential association between apolipoprotein B and LDL cholesterol and cerebral atherosclerosis according to pre-stroke statin use

BACKGROUND AND AIMS

To reduce cardiovascular risk, low-density lipoprotein cholesterol (LDL-C) is the primary target of statin treatment, while apolipoprotein B (ApoB) is secondary. We investigated the association between atherosclerotic stenosis and LDL-C or ApoB levels and whether a difference in association exists according to pre-admission statin use in ischemic stroke patients.

METHODS

This retrospective cross-sectional study included consecutive patients with acute ischemic stroke or transient ischemic attack who underwent lipid profile and angiographic testing. Patients were categorized into four groups according to stenosis location: normal, extracranial atherosclerotic stenosis (ECAS), intracranial atherosclerotic stenosis (ICAS), or ECAS + ICAS. Subgroup analyses were performed by pre-admission statin use.

RESULTS

Of the 6338 patients included, 1980 (31.2%) were in the normal group, 718 (11.3%) in the ECAS group, 1845 (29.1%) in the ICAS group, and 1795 (28.3%) in the ECAS + ICAS group. Both LDL-C and ApoB levels were associated with every location of stenosis. A significant interaction was found between pre-admission statin use and LDL-C level (p for interaction <0.05). LDL-C was associated with stenosis only in statin-naïve patients, whereas ApoB was associated with ICAS, with or without ECAS, in both statin-naïve and statin-treated patients. ApoB also showed a consistent association with symptomatic ICAS in both statin-treated and statin-naïve patients, whereas LDL-C did not.

CONCLUSIONS

ApoB was consistently associated with ICAS, particularly symptomatic stenosis, in both statin-naïve and statin-treated patients. The close association between ApoB levels and residual risk in statin-treated patients could be partially explained by these results.

Vulnerable plaque of the petrous internal carotid artery in embolic stroke of undetermined source

BACKGROUND AND PURPOSE

The association between nonstenotic plaque at the petrous internal carotid artery (ICA) and embolic stroke of undetermined source (ESUS) remains unknown. We aimed to test the hypothesis that the presence of a larger build-up of petrous plaque is more prevalent in the ipsilateral versus the contralateral side among ESUS patients without plaque in the intracranial and proximal ICA.

METHODS

From a total of 243 patients with ESUS and 160 patients with small-vessel disease (SVD) without proximal ICA plaque, we enrolled 88 ESUS and 103 SVD patients without ipsilateral nonstenotic intracranial and proximal ICA plaque in the present study. Targeting the petrous segment of the ICA on two sides, plaque burden including plaque thickness, lumen area, vessel area, wall area, and percentage of luminal stenosis, and composition features (presence/absence of the ruptured fibrous cap, ulcer plaque, thrombus, discontinuity of plaque surface [DPS], intraplaque hemorrhage and complicated plaque) were assessed by high-resolution magnetic resonance imaging.

RESULTS

We found a higher prevalence of petrous plaque thickness ≥3.5 mm ipsilateral versus contralateral to the stroke (25/88 [28.4%] vs. 12/88 [13.6%], odds ratio [OR] 3.60, 95% confidence interval [CI] 1.34-9.70), but this imbalance was not seen in SVD. In patients with plaque thickness ≥3.5 mm, the presence of DPS (OR 4.05, 95% CI 1.11-14.78) and complicated plaque (OR 5.00, 95% CI 1.10-22.82) was more closely related to an index ESUS, a finding that was not evident in the subgroup with petrous plaque <3.5 mm (p for interaction = 0.027).

CONCLUSIONS

The present study provided the first evidence supporting a potential etiological role of vulnerable petrous plaque in ESUS.

Pathophysiology, cellular and molecular mechanisms of large and small vessel diseases

Cerebrovascular disease (CVD) is the second most common cause of cognitive impairment and dementia in aged population. CVD presents in a myriad number of clinical ways based on the functional location of pathology. While primary clinical emphasis has been placed on motor, speech and visual deficits, vascular cognitive decline is a vastly under recognized and devastating condition afflicting millions of Americans. CVD, a disease of the blood vessels that supply blood to brain involves an integration between small and large vessels. Cerebral large vessel diseases (LVD) are associated with atherosclerosis, artery-to-artery embolism, intracardiac embolism and a large vessel stroke leading to substantial functional disability. Cerebral small vessel disease (SVD) is critically involved in stroke, brain hemorrhages, cognitive decline and functional loss in elderly patients. An evolving understanding of cellular and molecular mechanisms emphasizes that inflammatory vascular changes contribute to systemic pathologic conditions of the central nervous systems (CNS), with specific clinical presentations including, cognitive decline. Advances in an understanding of pathophysiology of disease processes and therapeutic interventions may help improve outcomes. This review will focus on large and small vessels diseases and their relationship to vascular cognitive decline, atherosclerosis, stroke, and inflammatory neurodegeneration. We will also emphasize the molecular and cellular mechanisms, as well as genetic and epigenetic factors associated with LVD and SVD.

Intracranial plaque with large lipid core is associated with embolic stroke of undetermined source

OBJECTIVE

To investigate an association between percentage lipid-rich necrotic core (LRNC) and an index ischemic stroke in an embolic stroke of undetermined source (ESUS) cohort.

METHODS

A total of 167 ESUS patients with 259 non-stenotic intracranial plaques including 155 ipsilateral and 104 contralateral to stroke were finally enrolled in the current analysis. The multi-dimensional parameters involving remodeling index (RI), plaque burden (PB), LRNC, discontinuity of plaque surface (DPS), intraplaque hemorrhage (IPH), and vulnerable plaque defined as presence of complicated plaque were evaluated by high-resolution magnetic resonance imaging.

RESULTS

We found that %LRNC was an independent predictor for ESUS in model 1 (OR: 2.574, 95% CI: 1.854-3.573, P < 0.001), and model 2 (OR: 2.550, 95% CI: 1.835-3.545, P < 0.001), but the association was not seen in PB. In receiver operating characteristic curve analysis, the discrimination of LRNC for ESUS was significantly superior to that of PB (absolute difference: 0.121, 95% CI: 0.056-0.205, P < 0.001). Importantly, a significantly positive synergy between the remodeling pattern and LRNC in response to plaque vulnerability was found by Sankey diagram (P for interaction = 0.001).

CONCLUSION

This is the first report that LRNC, beyond PB, may be correlated with an index ESUS, and a synergistic effect between positive remodeling and larger LRNC could promote plaque vulnerability. The findings suggest that a potential target subgroup may benefit from stroke prevention with intensive statin, although this must be confirmed in future.

Endovascular therapy versus medical treatment for symptomatic intracranial artery stenosis

BACKGROUND

Intracranial artery stenosis (ICAS) is an arterial narrowing in the brain that can cause stroke. Endovascular therapy (ET) and conventional medical treatment (CMT) may prevent recurrent ischaemic stroke caused by ICAS. However, there is no consensus on the best treatment for people with ICAS.

OBJECTIVES

To evaluate the safety and efficacy of endovascular therapy plus conventional medical treatment compared with conventional medical treatment alone for the management of symptomatic intracranial artery stenosis.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register, CENTRAL, MEDLINE, Embase, four other databases, and three trials registries on 16 August 2022. We contacted study authors and researchers when we required additional information.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing ET plus CMT with CMT alone for the treatment of symptomatic ICAS. ET modalities included angioplasty alone, balloon-mounted stent, and angioplasty followed by placement of a self-expanding stent. CMT included antiplatelet therapy in addition to control of risk factors such as hypertension, hyperlipidaemia, and diabetes.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the records to select eligible RCTs, then extracted data from them. We resolved any disagreements through discussion, reaching consensus decisions among the full team. We assessed risk of bias and applied the GRADE approach to assess the certainty of the evidence. The primary outcome was death by any cause or non-fatal stroke of any type within three months of randomisation. Secondary outcomes included all-cause death or non-fatal stroke of any type occurring more than three months after randomisation, ipsilateral stroke, transient ischaemic attack, ischaemic stroke, haemorrhagic stroke, death, restenosis, dependency, and health-related quality of life.

MAIN RESULTS

We included four RCTs with 989 participants who had symptomatic ICAS, with an age range of 18 to 85 years. We identified two ongoing RTCs. All trials had high risk of performance bias, as it was impossible to blind participants and personnel to the intervention. Three trials were terminated early. One trial was at high risk of attrition bias because of substantial loss to follow-up after one year and a high proportion of participants transferring from ET to CMT. The certainty of evidence ranged from low to moderate; we downgraded for imprecision. Compared to CMT alone, ET plus CMT probably increases the risk of short-term death or stroke (risk ratio (RR) 2.93, 95% confidence interval (CI) 1.81 to 4.75; 4 RCTs, 989 participants; moderate certainty), short-term ipsilateral stroke (RR 3.26, 95% CI 1.94 to 5.48; 4 RCTs, 989 participants; moderate certainty), short-term ischaemic stroke (RR 2.24, 95% CI 1.30 to 3.87; 4 RCTs, 989 participants; moderate certainty), and long-term death or stroke (RR 1.49, 95% CI 1.12 to 1.99; 4 RCTs, 970 participants; moderate certainty). Compared to CMT alone, ET plus CMT may increase the risk of short-term haemorrhagic stroke (RR 13.49, 95% CI 2.59 to 70.15; 4 RCTs, 989 participants; low certainty), short-term death (RR 5.43, 95% CI 1.21 to 24.40; 4 RCTs, 989 participants; low certainty), and long-term haemorrhagic stroke (RR 7.81, 95% CI 1.43 to 42.59; 3 RCTs, 879 participants; low certainty). It is unclear if ET plus CMT compared with CMT alone has an effect on the risk of short-term transient ischaemic attack (RR 0.79, 95% CI 0.30 to 2.07; 3 RCTs, 344 participants; moderate certainty), long-term transient ischaemic attack (RR 1.05, 95% CI 0.50 to 2.19; 3 RCTs, 335 participants; moderate certainty), long-term ipsilateral stroke (RR 1.78, 95% CI 1.00 to 3.17; 4 RCTs, 970 participants; moderate certainty), long-term ischaemic stroke (RR 1.56, 95% CI 0.77 to 3.16; 4 RCTs, 970 participants; moderate certainty), long-term death (RR 1.61, 95% CI 0.77 to 3.38; 4 RCTs, 951 participants; moderate certainty), and long-term dependency (RR 1.51, 95% CI 0.93 to 2.45; 4 RCTs, 947 participants; moderate certainty). No subgroup analyses significantly modified the effect of ET plus CMT versus CMT alone. The trials included no data on restenosis or health-related quality of life.

AUTHORS' CONCLUSIONS

This review provides moderate-certainty evidence that ET plus CMT compared with CMT alone increases the risk of short-term stroke and death in people with recent symptomatic severe ICAS. This effect was still apparent at long-term follow-up but appeared to be due to the early risks of ET; therefore, there may be no clear difference between the interventions in terms of their effects on long-term stroke and death. The impact of delayed ET intervention (more than three weeks after a qualifying event) warrants further study.

Association of Preoperative Vascular Wall Imaging Patterns and Surgical Outcomes in Patients With Unruptured Intracranial Saccular Aneurysms

BACKGROUND

MR vascular wall imaging (VWI) may have prognostic value in patients with unruptured intracranial aneurysms (UIAs).

OBJECTIVE

To evaluate the value of VWI as a predictor of surgical outcome in patients with UIAs.

METHODS

This prospective cohort study evaluated surgical outcomes in consecutive patients with UIAs who underwent surgical clipping at a single center. All participants underwent high-resolution VWI and were followed for at least 6 months. The primary clinical outcome was modified Rankin scale (mRS) score 6 months after surgery.

RESULTS

The number of patients in the no wall enhancement, uniform wall enhancement (UWE), and focal wall enhancement (FWE) groups was 37, 145, and 154, respectively. Incidence of postoperative complications was 15.5% in the FWE group, 12.4% in the UWE group, and 5.4% in the no wall enhancement group. The proportion of patients with mRS score >2 at the 6-month follow-up was significantly higher in the FWE group than in the UWE group (14.3% vs 6.9%; P = .0389). In the multivariate analysis, FWE (odds ratio, 2.573; 95% CI 1.001-6.612) and positive proximal artery remodeling (odds ratio, 10.56; 95% CI 2.237-49.83) were independent predictors of mRS score >2 at the 6-month follow-up.

CONCLUSION

Preoperative VWI can improve the surgeon's understanding of aneurysm pathological structure. Type of aneurysmal wall enhancement on VWI is associated with clinical outcome and incidence of salvage anastomosis and surgical complications.

The predictive value of nontraditional lipid parameters for intracranial and extracranial atherosclerotic stenosis: a hospital-based observational study in China

BACKGROUND

Ischemic strokes are primarily caused by intracranial and extracranial atherosclerotic stenosis. Nontraditional lipid parameters broaden traditional lipid profiles, better reflect the metabolism and interaction between different lipid components, and optimize the predictive ability of lipid profiles for atherosclerotic diseases. This research was carried out to investigate the predictive value of nontraditional lipid parameters for intracranial or extracranial atherosclerotic stenosis.

METHODS

The investigation collected data from inpatients who underwent cervical vascular ultrasonography, carotid CTA, cerebral artery CTA or MRA, and brain MRI or CT from December 2014 to December 2021. The nontraditional lipid parameters were calculated by collecting traditional lipid parameters. To evaluate the predictive power of nontraditional lipid parameters, logistic regression and receiver operating characteristic curve (ROC) analyses were performed.

RESULTS

Based on the inclusion and exclusion criteria, 545 patients were included. According to the imaging results, inpatients were divided into two groups, including no intracranial or extracranial atherosclerotic stenosis (n = 250) and intracranial or extracranial atherosclerotic stenosis (AS, n = 295). Among them, AS was further divided into three subgroups: intracranial atherosclerotic stenosis (ICAS), extracranial atherosclerotic stenosis (ECAS) and combined intracranial and extracranial atherosclerotic stenosis (IECAS). Logistic regression analysis showed that nontraditional lipid parameters, including the atherogenic index of plasma (AIP), TG/HDL-C, remnant cholesterol (RC), nonhigh-density lipoprotein cholesterol (non-HDL-C), lipoprotein combine index (LCI), atherogenic coefficient (AC), Castelli's index-I (CRI-I) and Castelli's index-II (CRI-II), were significantly correlated with intracranial or extracranial atherosclerotic stenosis (P < 0.05). Compared with other nontraditional lipid parameters, regardless of adjusting for potential confounding factors, AIP had a greater OR value in ICAS (OR = 4.226, 95% CI: 1.681-10.625), ECAS (OR = 2.993, 95% CI: 1.119-8.003) and IECAS (OR = 4.502, 95% CI: 1.613-12.561). ROC curve analysis revealed that nontraditional lipid parameters had good predictive power for intracranial or extracranial atherosclerotic stenosis.

CONCLUSIONS

This Chinese hospital-based study demonstrates that nontraditional lipid parameters (AIP, LCI, RC, CRI-II, AC, CRI-I and non-HDL-C) are effective predictors of intracranial and extracranial atherosclerotic stenosis, of which AIP may be a significant risk factor for predicting atherosclerotic arterial stenosis in the intracranial or extracranial regions.

Apolipoprotein E genotypes were not associated with intracranial atherosclerosis: a population-based autopsy study

BACKGROUND

Apolipoprotein E gene (APOE) ε4 allele is associated with a higher risk of carotid atherosclerosis, but less is known about the association of APOE with intracranial atherosclerotic disease (IAD). We aimed to investigate the association of APOE alleles with IAD in a cross-sectional autopsy study.

METHODS

We measured the stenosis in the 12 arteries of the Circle of Willis using postmortem morphometric measurements. The APOE polymorphism was determined by real-time polymerase chain reaction. We assessed the association between APOE polymorphism and IAD using regression models adjusted for sociodemographic and clinical variables. We also verified the modifier effect of age, sex, and race on this association. We stratified the analysis by age group to investigate the possibility of attrition bias.

RESULTS

In 400 participants (mean age=73.2±12.3 years old, 51% female, and 64% White), IAD was evaluated in 4,504 artery segments. APOE-ε4 was not associated with IAD nor with the number of artery stenosis compared to non-APOE-ε4 carriers. Sociodemographic variables did not modify this relationship. Among participants older than 70 years, there was a trend towards an association between APOE allele ε4 and a lower stenosis index in the middle cerebral artery, suggesting attrition bias related to the APOE-ε4 effect on mortality.

CONCLUSIONS

APOE alleles were not associated with IAD in this population-based autopsy study. Lower stenosis in older participants suggests the possibility of attrition bias.

True superficial temporal artery aneurysm: A case after extracranial-intracranial bypass surgery and a systematic review

Background

Nontraumatic true superficial temporal artery aneurysm (STAA) is rare, and its characteristics and pathogenesis are unclear.

Methods

We report a case of STAA and performed a systematic review of PubMed, Scopus, and Web of Science using the keyword "superficial temporal artery aneurysm" to include studies on STAA reported through July 2022. We excluded studies on STAA associated with trauma, arterial dissection, infection, or vasculitis.

Results

A 63-year-old woman who underwent left superficial temporal artery (STA)-middle cerebral artery bypass surgery 8 years previously was diagnosed with an aneurysm located at the left STA. The blood flow volume estimated by ultrasonography was higher in the left STA than in the contralateral counterpart (114 mL/min vs. 32 mL/min). She underwent clipping surgery to prevent aneurysmal rupture without sequela. The lesion was diagnosed as a true aneurysm by histology. The systematic review identified 63 cases (including the present case) of nontraumatic true STAA. The median age of the patients was 57 (interquartile range [IQR]: 41-70) years. Most (90.5%) cases were detected as a palpable mass. Aneurysmal rupture occurred in only 1 (1.6%) case, despite the large size of aneurysms (median size: 13 [IQR: 8-20] mm) and the high frequency (33.3%) of aneurysmal growth during observation. Most (93.7%) patients underwent surgical resection of STAA without sequela.

Conclusion

Our findings suggest that the pathogenesis of true STAA is promoted by hemodynamic stress. The systematic review clarified patients' and aneurysmal characteristics and treatment outcomes, providing further insight into the pathogenesis of nontraumatic true STAA.

eICAB: A novel deep learning pipeline for Circle of Willis multiclass segmentation and analysis

BACKGROUND

The accurate segmentation, labeling and quantification of cerebral blood vessels on MR imaging is important for basic and clinical research, yet results are not generalizable, and often require user intervention. New methods are needed to automate this process.

PURPOSE

To automatically segment, label and quantify Circle of Willis (CW) arteries on Magnetic Resonance Angiography images using deep convolutional neural networks.

MATERIALS AND METHODS

MRA images were pooled from three public and private databases. A total of 116 subjects (mean age 56 years ± 21 [standard deviation]; 72 women) were used to make up the training set (N=101) and the testing set (N=15). In each image, fourteen arterial segments making up or surrounding the CW were manually annotated and validated by a clinical expert. Convolutional neural network (CNN) models were trained on a training set to be finally combined in an ensemble to develop eICAB. Model performances were evaluated using (1) quantitative analysis (dice score on test set) and (2) qualitative analysis (external datasets, N=121). The reliability was assessed using multiple MRAs of healthy participants (ICC of vessel diameters and volumes on test-retest).

RESULTS

Qualitative analysis showed that eICAB correctly predicted the large, medium and small arteries in 99±0.4%, 97±1% and 88±7% of all images, respectively. For quantitative assessment, the average dice score coefficients for the large (ICAs, BA), medium (ACAs, MCAs, PCAs-P2), and small (AComm, PComm, PCAs-P1) vessels were 0.76±0.07, 0.76±0.08 and 0.41±0.27, respectively. These results were similar and, in some cases, statistically better (p<0.05) than inter-expert annotation variability and robust to image SNR. Finally, test-retest analysis showed that the model yielded high diameter and volume reliability (ICC=0.99).

CONCLUSION

We have developed a quick and reliable open-source CNN-based method capable of accurately segmenting and labeling the CW in MRA images. This method is largely independent of image quality. In the future, we foresee this approach as a critical step towards fully automated analysis of MRA databases in basic and clinical research.

Contribution of intracranial artery stenosis to white matter hyperintensities progression in elderly Chinese patients: A 3-year retrospective longitudinal study

Background and purpose

There have been controversial results in previous studies for the association between intracranial artery stenosis (ICAS) and white matter hyperintensities (WMHs), and the correlation of ICAS with the progression of WMHs is uncertain. The aim of this study was to investigate the association between ICAS and the progression of WMHs.

Methods

In this retrospective longitudinal study, we enrolled 302 patients aged 60 years and older who had received two brain MRI scans with a 3-year interval and was examined by CTA in the first MRI scan. We measured the stenosis of major intracranial arteries by CTA and assessed the progression of WMHs using the modified Rotterdam Progression scale (mRPS). We performed binary logistic regression analyses and established linear regression model to determine the relationship between the degree of ICAS and the progression of WMHs.

Results

A total of 302 patients were enrolled, of which 48.3% experienced WMHs progression. After adjustment for confounding factors, the patients with Grade 2 ICAS had an OR of 2.8 (95% CI 1.4–5.5), and those with Grade 3 ICAS had an OR of 3.0 (95% CI 1.2–7.3) for the progression of WMHs. The ICAS degree remained associated with PVWMHs but had an attenuated relation to SCWMHs. ICAS severity was significantly associated with WMHs progression scores, higher for Grade 3 ICAS [β (SE) = 0.18 (0.18)] followed by Grade 2 ICAS [β (SE) = 0.10 (0.15)] compared with Grade 1 ICAS.

Conclusions

Patients with more severe ICAS are more likely to have WMHs progression and have distinct relevancy to PVWMHs and SCWMHs, which may provide clues for understanding mechanisms of WMHs progression.

European Stroke Organisation guidelines on treatment of patients with intracranial atherosclerotic disease

The aim of the present European Stroke Organisation guideline is to provide clinically useful evidence-based recommendations on the management of patients with intracranial atherosclerotic disease (ICAD). The guidelines were prepared following the Standard Operational Procedure of the European Stroke Organisation guidelines and according to GRADE methodology. ICAD represents a major cause of ischemic stroke worldwide, and patients affected by this condition are exposed to a high risk for future strokes and other major cardiovascular events, despite best medical therapy available. We identified 11 relevant clinical problems affecting ICAD patients and formulated the corresponding Population Intervention Comparator Outcomes (PICO) questions. The first two questions refer to the asymptomatic stage of the disease, which is being increasingly detected thanks to the routine use of noninvasive vascular imaging. We were not able to provide evidence-based recommendations regarding the optimal detection strategy and management of asymptomatic ICAD, and further research in the field is encouraged as subclinical ICAD may represent a big opportunity to improve primary stroke prevention. The second block of PICOs (3-5) is dedicated to the management of acute large vessel occlusion (LVO) ischemic stroke caused by ICAD, a clinical presentation of this disease that is becoming increasingly relevant and problematic, since it is associated with more refractory endovascular reperfusion procedures. An operational definition of probable ICAD-related LVO is proposed in the guideline. Despite the challenging context, no dedicated randomized clinical trials (RCTs) were identified, and therefore the guideline can only provide with suggestions derived from observational studies and our expert consensus, such as the escalated use of glycoprotein IIb-IIIa inhibitors and angioplasty/stenting in cases of refractory thrombectomies due to underlying ICAD. The last block of PICOs is devoted to the secondary prevention of patients with symptomatic ICAD. Moderate-level evidence was found to recommend against the use of oral anticoagulation as preferred antithrombotic drug, in favor of antiplatelets. Low-level evidence based our recommendation in favor of double antiplatelet as the antithrombotic treatment of choice in symptomatic ICAD patients, which we suggest to maintain during 90 days as per our expert consensus. Endovascular therapy with intracranial angioplasty and or stenting is not recommended as a treatment of first choice in high-grade symptomatic ICAD (moderate-level evidence). Regarding neurosurgical interventions, the available evidence does not support their use as front line therapies in patients with high-grade ICAD. There is not enough evidence as to provide any specific recommendation regarding the use of remote ischemic conditioning in ICAD patients, and further RCTs are needed to shed light on the utility of this promising therapy. Finally, we dedicate the last PICO to the importance of aggressive vascular risk factor management in ICAD, although the evidence derived from RCTs specifically addressing this question is still scarce.

Association between carotid atherosclerosis and presence of intracranial atherosclerosis using three-dimensional high-resolution vessel wall magnetic resonance imaging in asymptomatic patients with type 2 diabetes

AIMS

Carotid atherosclerosis (CAS) is associated with a high risk of cardiovascular diseases. We aimed to investigate whether CAS is associated with the presence of intracranial atherosclerosis (ICAS).

METHODS

A total of 69 asymptomatic patients with type 2 diabetes (36 with CAS and 33 without CAS) who were free of cerebrovascular disease were enrolled in this case-control study. CAS was defined as a mean carotid intima-media thickness ≥ 1.0 mm or carotid plaque. The presence of ICAS was identified using three-dimensional high-resolution vessel wall magnetic resonance imaging.

RESULTS

There was no difference between the case and control groups in baseline characteristics, such as age, the proportion of men, duration of diabetes, and other cardiometabolic risk factors. The prevalence of ICAS was significantly higher in patients with CAS than those without CAS (72.2 % vs 48.5 %, P = 0.044). CAS was significantly associated with the presence of ICAS, even after adjusting other covariates (odds ratio [OR], 3.19; 95 % confidence interval [CI] 1.09-9.33, P = 0.034). In addition, CAS was significantly associated with the presence of multiple ICAS lesions (OR, 5.57; 95 % CI 1.75-17.78, P = 0.004).

CONCLUSIONS

CAS is significantly and independently associated with the presence and extent of ICAS in asymptomatic patients with type 2 diabetes.

Systolic blood pressure and recurrent stroke in patients with different lesion patterns on diffusion weighted imaging

Little is known about the relationship between baseline systolic blood pressure (SBP) and subsequent clinical events in patients with different lesion patterns on diffusion weighted imaging (DWI). We analyzed the Acute Non‐disabling Cerebrovascular Events (CHANCE) trial dataset. Patients were categorized into negative DW imaging (no detectable lesions), lacunar infarction (single lesion ≤15 mm) and non‐lacunar infarction (single lesion >15 mm or multiple lesions) based on lesion patterns on DWI. The primary outcome was recurrent stroke within 90 days. Cox proportional hazards models were used to assess the association between SBP levels and stroke outcomes in patients with different lesion patterns. A total of 1089 patients were analyzed. We found 258 cases (23.7%) with negative DW imaging, 392 (36.0%) with lacunar infarction and 439 (40.3%) with non‐lacunar infarction. Patients with non‐lacunar infarction had the highest incidence of stroke at 90‐day (P < .001). In non‐lacunar infarction group, compared with SBP < 160 mmHg, patients with SBP ≥ 160 mmHg had significantly higher risk of 90‐day recurrent stroke (20.3% vs. 10.7%; adjusted hazard ratio 1.81, 95% confidence interval 1.09–3.00). No significant association was found between SBP and clinical outcomes in patients with negative DWI and lacunar stroke groups. The result at 1 year was similar as at 90‐day. Therefore, non‐lacunar infarction, the most common lesion pattern in CHANCE study, had the highest risk of recurrent stroke and combined vascular events both in 90 days and 1 year. High baseline SBP was significantly associated with increased risk of short‐ and long‐term recurrent strokes in patients with non‐lacunar infarction.

Elevated hs-CRP and Symptomatic Intracranial/Extracranial Artery Stenosis Predict Stroke Recurrence after Acute Ischemic Stroke or TIA

AIM

This study aimed to investigate the relationship between symptomatic or asymptomatic intracranial/extracranial artery stenosis and high-sensitivity C-reactive protein (hs-CRP) levels in patients with acute ischemic stroke (AIS) or transient ischemic attack (TIA).

METHODS

This study included 10404 patients from the Third China National Stroke Registry. Patients were divided into four or six groups according to patterns of intracranial or extracranial artery stenosis and hs-CRP levels. The outcomes were recurrence of ischemic stroke, stroke, and combined vascular events (CVE) at 1 year. The associations between different combinations of hsCRP levels and patterns of artery stenosis and recurrent events were analyzed by multivariable Cox regression models.

RESULTS

Patients in Group III (hs-CRP ＜3＋symptomatic intracranial or extracranial artery stenosis) had higher risk of recurrent ischemic stroke (adjusted hazard ratio (HR) 1.73, 95% confidence interval (CI) 1.20-2.48,p=0.003). Those in Group VI (hs-CRP ≥ 3＋symptomatic intracranial or extracranial artery stenosis) had the highest risk of recurrent ischemic stroke (HR 2.04, 95% CI 1.42-2.92, p=0.0001) within 1 year compared with Group I (hs-CRP ＜3＋no artery stenosis). Asymptomatic intracranial or extracranial artery stenosis did not increase the risk of ischemic events compared with no artery stenosis regardless of hs-CRP levels.

CONCLUSION

Symptomatic intracranial or extracranial artery stenosis was associated with increased risk of recurrent ischemic stroke, stroke, and CVE at 1 year in patients with AIS or TIA, especially in patients with elevated hs-CRP levels. Asymptomatic intracranial or extracranial artery stenosis did not increase the risk of ischemic events compared with no artery stenosis regardless of hs-CRP levels.

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.