Stroke etiology and collaterals: atheroembolic strokes have greater collateral recruitment than cardioembolic strokes

Communicating Arteries and Leptomeningeal Collaterals: A Synergistic but Independent Effect on Patient Outcomes after Stroke

The collateral system is a compensatory mechanism activated in the acute phase of an ischemic stroke. It increases brain perfusion to the hypoperfused area. Arteries of the Willis' circle supply antegrade blood flow, while pial (leptomeningeal) arteries direct blood via retrograde flow. The aim of our retrospective study was to investigate the relationship between both collateral systems, computed tomography perfusion (CTP) values, and functional outcomes in acute stroke patients. Overall, 158 patients with anterior circulation stroke who underwent mechanical thrombectomy were included in the study. We analyzed the presence of communicating arteries and leptomeningeal arteries on computed tomography angiography. Patients were divided into three groups according to their collateral status. The main outcomes were the rate of functional independence 3 months after stroke (modified Rankin scale score, mRS) and mortality rate. Our study suggests that the collateral status, as indicated by the three groups (unfavorable, intermediate, and favorable), is linked to CT perfusion parameters, potential recuperation ratio, and stroke outcomes. Patients with favorable collateral status exhibited smaller core infarct and penumbra volumes, higher mismatch ratios, better potential for recuperation, and improved functional outcomes compared to patients with unfavorable or intermediate collateral status.

Association of Carotid Artery Disease with Collateralization and Infarct Growth in Patients with Acute Middle Cerebral Artery Occlusion

BACKGROUND AND PURPOSE

Collaterals are important in large vessel occlusions (LVO), but the role of carotid artery disease (CAD) in this context remains unclear. This study aimed to investigate the impact of CAD on intracranial collateralization and infarct growth after thrombectomy in LVO.

MATERIALS AND METHODS

All patients who underwent thrombectomy due to M1 segment occlusion from 01/2015 to 12/2021 were retrospectively included. Internal carotid artery stenosis according to NASCET was assessed on the affected and nonaffected sides. Collaterals were assessed according to the Tan score. Infarct growth was quantified by comparing ASPECTS on follow-up imaging with baseline ASPECTS.

RESULTS

In total, 709 patients were included, 118 (16.6%) of whom presented with CAD (defined as severe stenosis ≥70% or occlusion ipsilaterally), with 42 cases (5.9%) being contralateral. Good collateralization (Tan 3) was present in 56.5% of the patients with ipsilateral CAD and 69.1% of the patients with contralateral CAD. The ipsilateral stenosis grade was an independent predictor of good collateral supply (adjusted OR: 1.01; NASCET point, 95% CI: 1.00-1.01; P = .009), whereas the contralateral stenosis grade was not (P = .34). Patients with ipsilateral stenosis of ≥70% showed less infarct growth (median ASPECTS decay: 1; IQR: 0-2) compared with patients with 0%-69% stenosis (median: 2; IQR: 1-3) (P = .005). However, baseline ASPECTS was significantly lower in patients with stenosis of 70%-100% (P < .001). The results of a multivariate analysis revealed that increasing ipsilateral stenosis grade (adjusted OR: 1.0; 95% CI: 0.99-1.00; P = .004) and good collateralization (adjusted OR: 0.5; 95% CI: 0.4-0.62; P < .001) were associated with less infarct growth.

CONCLUSIONS

CAD of the ipsilateral ICA is an independent predictor of good collateral supply. Patients with CAD tend to have larger baseline infarct size but less infarct growth.

Blood pressure variability and outcome in atherosclerosis versus cardioembolism cerebral large vessel occlusion after successful thrombectomy

Higher blood pressure variability (BPV) has been proven associated with worse functional outcome after endovascular treatment (EVT). However, this association is not established according to different stroke etiologies. In this study, we compared patients with the two highest proportions of stroke etiologies-cardioembolism (CE) and large-artery atherosclerosis (LAA), aiming to explore appropriate strategies of BP management for different etiologies. We enrolled patients with large vessel occlusion (LVO) in anterior circulation who underwent EVT and achieved successful recanalization retrospectively. 24-h blood pressure (BP) and BPV measured as blood pressure reduction (BPr), standard deviation (SD), coefficient of variation (CV), successive variation (SV), average real variability (ARV) after EVT were collected for systolic blood pressure (SBP) and diastolic blood pressure (DBP). The favorable outcome was defined as functional independence by 90-day modified Rankin Scale (mRS 0-2). In our cohort, higher BPV parameters significantly resulted in 90d functional dependence in CE-LVO patients (SBPSV OR: 1.083, 95%CI = 1.009-1.163; SBPARV OR: 1.121, 95%CI = 1.019-1.233; DBPSD OR: 1.124, 95%CI = 1.007-1.1256; DBPCV OR: 1.078, 95%CI = 1.002-1.161). However, for LAA-LVO patients, no positive results correlated 90d functional dependence with 24-hour BPV. Additionally, 90d functional dependence in CE patients with poor collaterals were significantly dependent on post-procedural BPV (DBPmax OR: 1.044, 95%CI = 1.002-1.087; DBPSD OR: 1.229, 95%CI = 1.022-1.1.479; DBPCV OR: 1.143, 95%CI = 1.009-1.295). Whereas to patients with good collaterals, there did not exist such a correlation. In summary, stroke etiologies should probably be taken into consideration to optimize individualized BP management strategies. In order to achieve better clinical outcomes for patients with acute ischemic stroke due to large vessel occlusion, stricter blood pressure management should be taken in cardioembolic stroke patients in contrast with large artery atherosclerotic stroke patients after successful endovascular therapy.

Automated evaluation of collateral circulation for outcome prediction in acute ischemic stroke

INTRODUCTION

The assessment of collateral circulation in acute ischemic stroke management is essential. Modern tools, such as Brainomix's e-CTA, powered by artificial intelligence, provide detailed insights into collateral assessment. This retrospective study aims to identify factors contributing to favorable collateral status and compare outcomes between patients with good collaterals (grade 3) and fair collaterals (grade 0-2).

METHOD

This retrospective study included 97 patients admitted to the Stroke Unit at the Hospital de Clínicas of the Federal University of Paraná, Brazil, from September 2021 to January 2023. Comparative analyses involved demographic factors, cardiovascular risk factors, and the combined outcome of mortality and moderate to severe disability at discharge, 30-day, and 90-day follow-ups.

RESULTS

Among the 97 cases, 58.8 % showed 'good collaterals' with a grade 3 status. Variables affecting collateral status included age (p = 0.042), neutrophil-lymphocyte ratio (p = 0.005), and initial NIHSS scores (p<0.001). The presence of good collaterals according to e-CTA reduced the odds of death and moderate-severe disability at discharge (p = 0.003; OR 0.27) and at 30 days (p = 0.015; OR 0.33), although this effect diminished at the 90-day mark after multivariate analysis.

DISCUSSION

Automated collateral assessment through e-CTA is a valuable tool in acute ischemic stroke evaluation. Good e-CTA collateral score serve as a promising imaging biomarker, guiding informed clinical decisions during Stroke Unit hospitalizations. This study highlights the relationship between collaterals and stroke outcomes and underscores the potential for AI-driven tools to enhance stroke care management.

Predicting 3-month Functional Outcome After Endovascular Thrombectomy in Patients with Anterior Circulation Occlusion with an Arterial Transit Artifact Grading System

PURPOSE

The objective of this study was to evaluate the relationship between arterial transit artifact (ATA), arterial spin labeling (ASL) perfusion imaging, and the outcome of patients with acute ischemic stroke (AIS) due to occlusion of large vessels in anterior circulation after endovascular thrombectomy (EVT).

METHODS

Patients with anterior circulation occlusion treated with EVT between October 2017 and December 2021 were enrolled in this retrospective study, and ATA was quantified by a 4-point scale. A favorable outcome was defined by modified Rankin Scale (mRS) scores of 0-2 at 3 months. To identify independent predictors of favorable outcome, age, sex, risk factors, baseline National Institutes of Health Stroke Scale (NIHSS) score, site of occlusion, cause of stroke, and early reperfusion were evaluated with univariate and multivariate analyses. Predictive accuracy was evaluated by calculating the area under the receiver operating characteristic (ROC) curve (AUC) for the model.

RESULTS

In this study 187 patients (age, 65.0 ± 12.5 years; men, 55%) were evaluated. Younger age (odds ratio, OR, 0.95; 95% confidence interval, CI, 0.92-0.98, p = 0.002), lower baseline NIHSS score (OR, 0.88; 95% CI, 0.82-0.94, p < 0.001), and lower ATA score (OR, 1.14; 95% CI, 1.06-1.22, p < 0.001) were independently associated with favorable outcomes in multivariate analysis. The ATA score has moderate to good accuracy in predicting favorable outcomes (AUC, 0.753).

CONCLUSION

A high ATA score as a potential predictor, can help identify patients who may benefit from EVT.

Diagnostic Value of Perfusion Parameters for Differentiation of Underlying Etiology in Internal Carotid Artery Occlusions

PURPOSE

Occlusions of the internal carotid artery (ICA) may be caused by dissection, embolic or macroangiopathic pathogenesis, which partially influences the treatment; however, inferring the underlying etiology in computed tomography angiography can be challenging. In this study, we investigated whether computed tomography perfusion (CT-P) parameters could be used to distinguish between etiologies.

METHODS

Patients who received CT‑P in acute ischemic stroke due to ICA occlusion between 2012 and 2019 were retrospectively analyzed. Group comparisons between etiologies regarding the ratios of CT‑P parameters between both hemispheres for relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF), time to maximum (Tmax), and mean transit time (MTT) were calculated by one-factorial analysis of variance (ANOVA) and compared by pairwise Bonferroni post hoc tests. An receiver operating characteristics (ROC) analysis was performed if differences in group comparisons were found. Multinomial logistic regression (MLR) including pretherapeutic parameters was calculated for etiologies.

RESULTS

In this study 69 patients (age = 70 ± 14 years, dissection = 10, 14.5%, embolic = 19, 27.5% and macroangiopathic = 40, 58.0%) were included. Group differences in ANOVA were only found for MTT ratio (p = 0.003, η2 = 0.164). In the post hoc test, MTT ratio showed a differentiability between embolic and macroangiopathic occlusions (p = 0.002). ROC analysis for differentiating embolic and macroangiopathic ICA occlusions based on MTT ratio showed an AUC of 0.77 (p < 0.001, CI = 0.65-0.89) and a cut-off was yielded at a value of 1.15 for the MTT ratio (sensitivity 73%, specificity 68%). The MLR showed an overall good model performance.

CONCLUSION

It was possible to differentiate between patients with embolic and macroangiopathic ICA occlusions based on MTT ratios and to define a corresponding cut-off. Differentiation from patients with dissection versus the other etiologies was not possible by CT‑P parameters in our sample.

Outcome Comparison of Endovascular Treatment for Acute Large Vessel Occlusion Due to Large Artery Atherosclerosis and Cardioembolism in the Chinese Population: Data from the ANGEL Registry

Background and Purpose

Studies on outcome comparison after endovascular treatment (EVT) for large vessel occlusion (LVO) between large artery atherosclerosis (LAA) and cardioembolism (CE) in the Asian population are scarce. We aimed to compare the baseline characteristics and clinical outcomes after EVT for anterior circulation LVO with LAA and CE in the Chinese population.

Methods

Patients were selected from the ANGEL registry and divided into LAA and CE groups. The primary outcome was the 90-day modified Rankin Scale (mRS) 0-2. The secondary outcomes were 90-day mRS distribution, 90-day mRS 0-1, 90-day mRS 0-3, and early neurological improvement. The safety outcomes included death, symptomatic intracranial hemorrhage, and any intracranial hemorrhage. We conducted logistic regression models with adjustments to compare the outcomes.

Results

A total of 632 patients were included, of whom, 488 were in the LAA group and 144 were in the CE group. No significant difference in 90-day mRS 0-2 was observed between LAA and CE groups (55.7%vs.43.1%, odds ratio[OR] 1.19, 95% confidence interval(CI), 0.92-1.53, P=0.190). The LAA group exhibited a higher frequency of mRS 0-3 compared to the CE group (69.1% vs 32.6%, OR1.32, 95% CI 1.02-1.72, P=0.038). However, the incidence of death within 90 days did not significantly differ between the LAA and CE groups (10.9%vs.24.3%, OR0.91, 95% CI0.66-1.25, P=0.545), nor did the occurrences of symptomatic intracranial hemorrhage(SICH) (4.5%vs.9.7%,OR1.08, 95% CI 0.65-1.78, P=0.779) or intracranial hemorrhage(ICH) (21.9%vs.30.6%, OR 0.94, 95% CI0.71-1.25, P=0.680). Moreover, no significant disparities were detected in other outcomes between the two groups (All P>0.05).

Conclusion

In the ANGEL registry, a higher prevalence of patients undergoing EVT for acute anterior circulation LVO with LAA was found than those with CE. However, our study revealed that the efficacy and safety of EVT remained consistent regardless of the stroke's etiology such as LAA or CE.

Clinical efficacy and safety of endovascular treatment for patients with wake-up stroke with large vessel occlusion guided by NCCT-ASPECTS

OBJECTIVE

To evaluate the clinical efficacy and safety of 6 to 24 h endovascular therapy (EVT) in patients with wake-up stroke (WUS) with acute large vessel occlusion (LVO) of the anterior circulation guided by noncontrast computed tomography-Alberta stroke program early CT score (NCCT-ASPECTS).

METHODS

Fifty-three patients with WUS with acute LVO of the anterior circulation who were treated at the Sir Run Run Shaw Hospital of Zhejiang Medical College from January 2018 to March 2021 were retrospectively analyzed. The patients were divided into NCCT-ASPECTS or CT perfusion groups. Baseline data, perioperative data, and 90-d prognostic information were compared between the two groups. Multivariable logistic regression analysis was used to determine the independent factors influencing outcomes.

RESULTS

There were no significant differences in the good prognosis, symptomatic intracranial hemorrhage, and mortality rates between the two groups (P > 0.05). Multivariate logistic regression analysis showed that the puncture-recanalization time was an independent factor for good prognosis.

CONCLUSION

Based on NCCT-ASPECTS guidance, EVT in patients with WUS for acute LVO of the anterior circulation within 6 to 24 h may be safe and effective.

Diagnosis and management of tandem occlusion in acute ischemic stroke

Approximately 20-30% of patients with acute ischemic stroke, caused by large intracranial vessel occlusion, have a tandem lesion, defined as simultaneous presence of high-grade stenosis or occlusion of the cervical internal carotid artery and thromboembolic occlusion of the intracranial terminal internal carotid artery or its branches, usually the middle cerebral artery. Patients with tandem lesions have usually worse outcomes than patients with single intracranial occlusions, and intravenous thrombolysis is less effective in these patients. Although endovascular thrombectomy is currently a cornerstone therapy in the management of acute ischemic stroke due to large vessel occlusion, the optimal management of extracranial carotid lesions in tandem occlusion remains controversial. Acute placement of a stent in the cervical carotid artery lesion is the most used therapeutic strategy compared with stented balloon angioplasty and thrombectomy alone without carotid artery revascularization; however, treatment strategies in these patients are often more complex than with single occlusion, so treatment decisions can change based on clinical and technical considerations. The aim of this review is to analyze the results of different studies and trials, investigating the periprocedural neurointerventional management of patients with tandem lesions and the safety, efficacy of the different technical strategies available as well as their impact on the clinical outcome in these patients, to strengthen current recommendations and thus optimize patient care.

Diagnosis and Management of Atrial Fibrillation in Acute Ischemic Stroke in the Setting of Reperfusion Therapy: Insights and Strategies for Optimized Care

Reperfusion therapy in the form of intravenous thrombolysis (IVT) and endovascular thrombectomy (EVT) has revolutionised the field of stroke medicine. Atrial fibrillation (AF) patients constitute a major portion of the overall stroke population; however, the prevalence of AF amongst acute ischemic stroke (AIS) patients receiving reperfusion therapy remains unclear. Limitations in our understanding of prevalence in this group of patients are exacerbated by difficulties in appropriately diagnosing AF. Additionally, the benefits of reperfusion therapy are not consistent across all subgroups of AIS patients. More specifically, AIS patients with AF often tend to have poor prognoses despite treatment relative to those without AF. This article aims to present an overview of the diagnostic and therapeutic management of AF and how it mediates outcomes following stroke, most specifically in AIS patients treated with reperfusion therapy. We provide unique insights into AF prevalence and outcomes that could allow healthcare professionals to optimise the treatment and prognosis for AIS patients with AF. Specific indications on acute neurovascular management and secondary stroke prevention in AIS patients with AF are also discussed.

Association between left atrial enlargement and poor cerebral collaterals in large vessel occlusion

OBJECTIVES

Left atrial enlargement (LAE) is a known risk factor for atrial fibrillation, a common cause of large vessel occlusion (LVO) leading to ischemic stroke. While robust cerebral collaterals protect penumbral tissue from infarction, the effect of structural heart disease on cerebral collaterals remains uncertain. This study aims to investigate the association between LAE and cerebral collaterals in patients with acute LVO stroke.

MATERIALS AND METHODS

We conducted a retrospective study of consecutive patients with middle cerebral and/or internal carotid LVO who underwent endovascular thrombectomy (EVT) between 2012 to 2020. Consecutive patients with echocardiography and computed tomography angiography (CTA) of the head were included. Multivariate logistic regression analysis was performed to evaluate the relationship between LAE and poor cerebral collaterals, adjusting for demographics (age, sex, race) and vascular risk factors (hypertension, diabetes and smoking).

RESULTS

The study included 235 patients with mean age of 69±15 years and an initial mean National Institutes of Health Stroke Scale score of 18. Of these, 89 (37.9 %) had LAE, and 105 (44.7 %) had poor collaterals. Patients with LAE were more likely to have poor collaterals compared to those without LAE (58.4 % vs 36.3 %, P = 0.001). LAE was independently associated with higher odds of poor collaterals (odds ratio, 2.47; P = 0.001), even after adjusting for covariables (odds ratio 1.84, P = 0.048).

CONCLUSIONS

Our study demonstrated a significant association between LAE and poor cerebral collaterals in patients with LVO stroke undergoing EVT. Further research is warranted to explore potential shared mechanisms, such as endothelial dysfunction, underlying this heart-brain association.

High-resolution magnetic resonance imaging of acute intracranial artery thrombus

BACKGROUND AND PURPOSE

The development of high-resolution magnetic resonance imaging (HR-MRI) has enabled submillimeter-level evaluation of intracranial artery plaque and luminal thrombus. We sought to investigate the value of HR-MRI in assessing the pathogenesis of acute intracranial artery thrombus.

METHODS

We examined the presence of intracranial thrombus on three-dimensional T1-weighted HR-MRI in acute ischemic stroke patients with intracranial artery occlusion on magnetic resonance angiography. We defined two thrombus-related HR-MRI features (peri-thrombus plaque and distal residual flow beyond the thrombus) and analyzed their association with potential embolic sources.

RESULTS

Luminal thrombus and a shrunken artery without luminal thrombus were detected in 162 (96.4%) and six (3.6%) of 168 patients with intracranial artery occlusion, respectively. Among 111 patients with culprit major artery thrombus, peri-thrombus plaques were observed in 46.8% and distal residual flow beyond the thrombus in 64.0%. Patients with peri-thrombus plaque had a higher prevalence of diabetes (44.2% vs. 25.4%; p = 0.037), a lower prevalence of potential sources of cardioembolism (0% vs. 16.9%; p = 0.002), and a nonsignificantly lower prevalence of potential embolic sources from extracranial arteries (9.6% vs. 20.3%; p = 0.186) than those without. Patients with distal residual flow beyond the thrombus had a lower prevalence of potential sources of cardioembolism (1.4% vs. 22.5%; p < 0.001) and smaller infarct volumes (5.0 [1.4-12.7] mL vs. 16.6 [2.4-94.6] mL; p = 0.012) than those without.

CONCLUSIONS

Our study showed that HR-MRI helps clarify the pathogenesis of acute intracranial artery thrombus. The presence of peri-thrombus plaque and distal residual flow beyond the thrombus favor the stroke mechanism of atherosclerosis rather than cardioembolism.

Integrative Approaches in Acute Ischemic Stroke: From Symptom Recognition to Future Innovations

Among the high prevalence of cerebrovascular diseases nowadays, acute ischemic stroke stands out, representing a significant worldwide health issue with important socio-economic implications. Prompt diagnosis and intervention are important milestones for the management of this multifaceted pathology, making understanding the various stroke-onset symptoms crucial. A key role in acute ischemic stroke management is emphasizing the essential role of a multi-disciplinary team, therefore, increasing the efficiency of recognition and treatment. Neuroimaging and neuroradiology have evolved dramatically over the years, with multiple approaches that provide a higher understanding of the morphological aspects as well as timely recognition of cerebral artery occlusions for effective therapy planning. Regarding the treatment matter, the pharmacological approach, particularly fibrinolytic therapy, has its merits and challenges. Endovascular thrombectomy, a game-changer in stroke management, has witnessed significant advances, with technologies like stent retrievers and aspiration catheters playing pivotal roles. For select patients, combining pharmacological and endovascular strategies offers evidence-backed benefits. The aim of our comprehensive study on acute ischemic stroke is to efficiently compare the current therapies, recognize novel possibilities from the literature, and describe the state of the art in the interdisciplinary approach to acute ischemic stroke. As we aspire for holistic patient management, the emphasis is not just on medical intervention but also on physical therapy, mental health, and community engagement. The future holds promising innovations, with artificial intelligence poised to reshape stroke diagnostics and treatments. Bridging the gap between groundbreaking research and clinical practice remains a challenge, urging continuous collaboration and research.

Blood Vessel Injuries of the Fingers: A Clinical Comparison of One- and Two-Arterial Blood Supply

Traumatic finger injuries are very common in emergency medicine. When patients present with finger injuries, there is often damage to the vascular nerve bundles, which requires subsequent reconstruction. It is unknown if repairing a unilaterally injured artery affects patients' recovery in a well-perfused finger. This retrospective cohort study compares the clinical outcomes of 11 patients with one-vessel supply (mean age 48.3 years; 7 males, 4 females) to 14 patients with two-vessel supply (mean age 44.5 years; 8 males, 6 females). The patient outcomes were assessed using patient questionnaires (Disabilities of Arm, Shoulder, and Hand (DASH), European Quality of Life 5 Dimensions 5 Level Version (EQ-5D-5L), and EuroQol visual analog scale (EQ-VAS)) and a clinical examination of hand function and imaging of circulatory efficiency. No significant changes were observed in the DASH, EQ-5D-5L, and EQ-VAS questionnaires. Clinical evaluation of hand function, measured by cold sensitivity, two-point discrimination, pain numerical analog scale, and grip strength also revealed no significant differences between cohorts. Blood flow measurements using thermal imaging revealed no effects on circulation in the affected digit. Collectively, the study finds reconstruction is not absolutely necessary when there is one intact digital artery as it is sufficient for healing and functional outcomes. We recommend finger artery reconstruction when both digital arteries are injured or if an immediate tension-free suture is possible.

Predictors and outcome of early neurological deterioration after endovascular thrombectomy: a secondary analysis of the DIRECT-MT trial

BACKGROUND

There is uncertainty regarding the predictors of early neurological deterioration (END) after endovascular thrombectomy in patients with acute ischemic stroke (AIS). Limited studies have focused on the effect of END on functional outcome. Our aim was to determine the predictors of END after endovascular thrombectomy in AIS and its effect on functional outcome at 90 days.

METHODS

This is a secondary analysis of the DIRECT-MT trial. Patients who failed to complete endovascular thrombectomy were additionally excluded. END was defined as ≥4-point increase in National Institutes of Health Stroke Scale score between admission and 24 hours after endovascular thrombectomy. Multivariable logistic regression was used to identify predictors for END and its effect on the modified Rankin Scale (mRS) score at 90 days.

RESULTS

Of 591 patients enrolled, 111 (18.8%) had postoperative END, which was associated with higher ordinal mRS score at 90 days (adjusted common OR (aOR) 6.968, 95% CI 4.444 to 10.926). Non-modifiable factors included baseline Alberta Stroke Program Early CT Score (aOR 0.883, 95% CI 0.790 to 0.987), systolic blood pressure (aOR 1.017, 95% CI 1.006 to 1.028), glucose level (aOR 1.178, 95% CI 1.090 to 1.273), collateral status (aOR 0.238, 95% CI 0.093 to 0.608), occlusion site (aOR 0.496, 95% CI 0.290 to 0.851) and the presence of an anterior communicating artery (aOR 0.323, 95% CI 0.148 to 0.707). Admission-to-groin puncture time (aOR 1.010, 95% CI 1.003 to 1.017), general anesthesia (aOR 2.299, 95% CI 1.193 to 4.444), number of passes (aOR 1.561, 95% CI 1.243 to 1.961) and contrast extravasation (aOR 6.096, 95% CI 1.543 to 24.088) were modifiable predictors for END.

CONCLUSIONS

Postoperative END is associated with adverse functional outcome. Several non-modifiable and modifiable factors can predict END and support future treatment decision-making to improve the potential utility of endovascular thrombectomy.

TRIAL REGISTRATION NUMBER

DIRECT-MT ClinicalTrials.gov NCT03469206.

Poor collateral flow with severe hypoperfusion explains worse outcome in acute stroke patients with atrial fibrillation

BACKGROUND

Atrial fibrillation (AF) is associated with poorer functional outcomes in acute stroke patients. It has been hypothesized that this is due to poor collateral recruitment.

AIMS

This study aimed to investigate the relationship between AF and collaterals with outcome in thrombectomy patients.

METHODS

This retrospective cohort study identified 1036 acute ischemic patients from the INternational Stroke Perfusion Imaging REgistry. The cohort was divided into two groups: 432 with AF and 604 without AF. Patients were stratified by collateral grades as good, moderate, and poor. Within each collateral grade, the prediction of AF versus No AF for good outcome (3-month modified Rankin Scale of 0-2) was determined. Then, within each collateral grade, perfusion was compared between those with and without AF.

RESULTS

AF was negatively associated with good outcome in patients with poor collaterals (26.7% vs 51.2% for AF vs No AF, odds ratio = 0.32 (95% confidence interval = 0.22-0.50), p < 0.001), but not in patients with good (50.9% vs 58.1% for AF vs No AF, odds ratio = 0.75 (0.46-1.23), p = 0.249) or moderate collaterals (43.6% vs 50.9% for AF vs No AF, odds ratio = 0.75 (0.47-1.18), p = 0.214). AF was associated with severe hypoperfusion only in patients with poor collateral flow (54.0 vs 35.5 mL for AF vs No AF, p < 0.001).

CONCLUSIONS

AF-related stroke is associated with more severe hypoperfusion and worse outcome in those with poor collaterals.

Endovascular Treatment for Acute Large Vessel Occlusion Due to Underlying Intracranial Atherosclerotic Disease

Intracranial atherosclerotic disease (ICAD) is one of the most common causes of acute ischemic stroke worldwide. Patients with acute large vessel occlusion due to underlying ICAD (ICAD-LVO) often do not achieve successful recanalization when undergoing mechanical thrombectomy (MT) alone, requiring rescue treatment, including intra-arterial thrombolysis, balloon angioplasty, and stenting. Therefore, early detection of ICAD-LVO before the procedure is important to enable physicians to select the optimal treatment strategy for ICAD-LVO to improve clinical outcomes. Early diagnosis of ICAD-LVO is challenging in the absence of consensus diagnostic criteria on noninvasive imaging and early digital subtraction angiography. In this review, we summarize the clinical and diagnostic criteria, prediction of ICAD-LVO prior to the procedure, and EVT strategy of ICAD-LVO and provide recommendations according to the current literature.

Effect of leukoaraiosis on collateral circulation in acute ischemic stroke treated with endovascular therapy: a meta-analysis

BACKGROUND AND OBJECTIVE

The recruitment of collateral circulation correlates with a balance of the microvasculature. Uncertainty remains to be made about the association of leukoaraiosis with leptomeningeal collaterals. To explore the effect of leukoaraiosis on leptomeningeal collaterals in patients treated with endovascular therapy.

METHODS

Observational studies exploring the correlation between leukoaraiosis and leptomeningeal collaterals in large vessel occlusion treated with endovascular therapy were searched from PubMed, EMBASE, and Cochrane Libraries databases. Two independent reviewers retrieved eligible literature, extracted purpose-related data, and utilized the Newcastle-Ottawa Scale to evaluate the risk of bias. A Mantel-Haenszel method was used to calculate the odds ratio (OR). Meta-regression and subgroup analyses were conducted to clarify heterogeneity.

RESULTS

Data from 10 studies with 1606 patients were extracted for pooled analysis. Compared to non-severe leukoaraiosis, patients with severe leukoaraiosis showed significant relevance to poor leptomeningeal collaterals (OR, 2.13; 95% confidence interval [1.27-3.57]; P = 0.004). Meta-regression indicated that sample size (coefficient = -0.007299, P = 0.035) and the number of female patients (coefficient = -0.0174709, P = 0.020) were sources of heterogeneity. Furthermore, all of the countries (USA versus France versus China, Q = 3.67, P = 0.159), various assessment scales of leukoaraiosis (the Fazekas scale versus Non-Fazekas scales, Q = 0.77, P = 0.379), and different imaging methods of leukoaraiosis (computed tomography versus magnetic resonance imaging, Q = 2.12, P = 0.146) and leptomeningeal collaterals (computed tomography angiography versus digital subtraction angiography, Q = 1.21, P = 0.271) showed no contribution to the effect size.

CONCLUSION

Severe leukoaraiosis is associated with poor leptomeningeal collaterals in patients treated with endovascular therapy. Further studies may focus on whether the finding applies to different stroke subtypes.

Collateral Circulation and BNP in Predicting Outcome of Acute Ischemic Stroke Patients with Atherosclerotic versus Cardioembolic Cerebral Large-Vessel Occlusion Who Underwent Endovascular Treatment

PURPOSE

The aim of this study was to verify the value of collateral circulation and B-type natriuretic peptide (BNP) in predicting clinical outcomes of patients with acute ischemic stroke (AIS) and their biomarker value for stroke subtypes before endovascular treatment (EVT).

PATIENTS AND METHODS

In this retrospective study, 182 patients who underwent EVT for unilateral anterior circulation large-vessel occlusion between March 2016 and January 2022 were analyzed. The modified collateral circulation scoring system on four-dimensional computed tomography angiography (4D CTA-CS) was used to assess collateral status, and stroke subtypes were determined according to the TOAST classification criteria. Patients were divided into good (mRS ≤ 2) and poor outcome (mRS > 2) groups based on their modified Rankin Scale (mRS) score at 3 months.

RESULTS

4D CTA-CS was an independent predictor of the clinical outcome for all AIS patients (odds ratio = 0.253; 95% CI, 0.147-0.437; p < 0.001), CE stroke patients (odds ratio = 0.513; 95% CI, 0.280-0.939; p = 0.030), and LAA stroke patients (odds ratio = 0.148; 95% CI, 0.049-0.447; p = 0.001). The BNP was a biomarker for clinical outcome prediction in CE (odds ratio = 1.004; 95% CI, 1.001-1.008; p = 0.005) but not in LAA patients. Combined with BNP, 4D CTA-CS improved predictive values for clinical outcomes (p < 0.05).

CONCLUSION

Collateral status and BNP could be used as independent predictors of clinical outcomes in AIS patients and could determine stroke subtypes (CE stroke or LAA stroke). In addition, the model of 4D CTA-CS combined with BNP was the most effective in predicting clinical outcomes compared with collateral status or BNP alone.

Thromboelastography as a predictor of functional outcome in acute ischemic stroke patients undergoing endovascular treatment

BACKGROUND

Thromboelastography (TEG) is a useful for predicting hemorrhagic transformation, early neurological deterioration, and functional outcome after stroke. We aimed to investigate whether TEG value could also be useful in predicting functional outcome via various intraprocedural and postprocedural factors in patients with acute large vessel occlusive stroke who underwent intraarterial thrombectomy (IAT).

METHODS

Patients with ischemic stroke who underwent IAT between March 2018 and March 2020 at two tertiary hospitals were included. The association between reaction time (R) and functional outcome was evaluated. The primary outcome was the achievement of functional independence defined as the achievement of a modified Rankin Scale (mRS) score of 0-2 at 3 months after the index stroke.

RESULTS

Among a total of 160 patients (mean age, 70.6 ± 12.3 years; 103 [64.4 %] men), 79 (49.3 %) achieved functional independence at 3 months. R, both as a continuous (odds ratio [OR]: 1.45, 95 % confidence interval [95 % CI]: 1.09-1.92, P = 0.011) and dichotomized parameters (R < 5 min [OR: 0.37, 95 % CI: 0.16-0.82, P = 0.014]), were inversely associated with increased odds of achieving functional independence (mRS score 0-2) after multivariable analysis. The association was still consistent when the outcome was the achievement of disability free (mRS score 0-1) or mRS score analyzed as an ordinal variable.

CONCLUSIONS

Decreased R, especially R < 5 min, was inversely associated with functional outcome pf stroke after EVT.

Endovascular treatment in patients with middle cerebral artery occlusion of different aetiologies

PURPOSE

The purpose of this study was to evaluate differences in endovascular treatment (EVT) outcomes in M1 segment middle cerebral artery occlusion (MCAO) patients with different pathologic subtypes.

METHODS

Patients with MCAO who received EVT from July 2014 to December 2020 were categorized into three groups: embolism without internal carotid artery steno-occlusion (MCAO-E), in situ atherosclerotic thrombosis (MCAO-AS) and embolism from tandem ICA steno-occlusion (MCAO-T). Baseline characteristics, EVT-related factors and clinical outcomes were compared between groups. Multivariable regression analyses were performed to evaluate the relationship between aetiologic classification and outcomes at 90 days after stroke.

RESULTS

Among eligible patients (n = 220), MCAO-E (n = 129, 58.6%) was the most common aetiology, followed by MCAO-AS (n = 47, 21.4%) and MCAO-T (n = 44, 20.0%). Patients with MCAO-E were significantly older but had a lower rate of dyslipidaemia and smoking history than those with MCAO-AS. Although patients with MCAO-AS and MCAO-T more often required rescue balloon angioplasty and stenting (p < 0.001), no significant difference in the rate of final recanalization was found. Patients in the MCAO-AS group obtained better functional outcomes (90-day modified Rankin Scale score, 0-2) (p = 0.002) and lower mortality than in the MCAO-E group (p = 0.009). On multivariable logistic regression, we failed to find that stroke subtype was an independent predictor of functional outcomes and mortality.

CONCLUSIONS

Patients with acute MCA M1 occlusion stroke due to different pathogeneses had comparable successful recanalization rates and functional independence at 90 days. The optimal management for MCAO patients with different aetiologies requires further research.

The impact of leptomeningeal collaterals in acute ischemic stroke: a systematic review and meta-analysis

OBJECTIVES

Leptomeningeal collaterals provide an alternate pathway to maintain cerebral blood flow in stroke to prevent ischemia, but their role in predicting the outcome is still unclear. So, our study aims at assessing the significance of collateral blood flow (CBF) in acute stroke.

METHODS

Electronic databases were searched under different MeSH terms from January 2000 to February 2019. Studies were included if there was available data on good and poor CBF in acute ischemic stroke (AIS). The clinical outcomes included were modified Rankin scale (mRS), recanalization, mortality, and symptomatic intracranial hemorrhage (sICH) at 90 days. Data was analyzed using a random-effect model.

RESULTS

A total of 47 studies with 8194 patients were included. Pooled meta-analysis revealed that there exist twofold higher likelihood of favorable clinical outcome (mRS ≤ 2) at 90 days with good CBF compared with poor CBF (RR: 2.27; 95% CI: 1.94-2.65; p < 0.00001) irrespective of the thrombolytic therapy [RR with IVT: 2.90; 95% CI: 2.14-3.94; p < 0.00001, and RR with IAT/EVT: 1.99; 95% CI: 1.55-2.55; p < 0.00001]. Moreover, there exists onefold higher probability of successful recanalization with good CBF (RR: 1.31; 95% CI: 1.15-1.49; p < 0.00001). However, there was 54% and 64% lower risk of sICH and mortality respectively in patients with good CBF in AIS (p < 0.00001).

CONCLUSIONS

The relative risk of favorable clinical outcome is more in patients with good pretreatment CBF. This could be explained due to better chances of recanalization combined with a lesser risk of intracerebral hemorrhage with good CBF status.

Clot-based radiomics model for cardioembolic stroke prediction with CT imaging before recanalization: a multicenter study

OBJECTIVES

To develop a clot-based radiomics model using CT imaging radiomic features and machine learning to identify cardioembolic (CE) stroke before mechanical thrombectomy (MTB) in patients with acute ischemic stroke (AIS).

MATERIALS AND METHODS

This retrospective four-center study consecutively included 403 patients with AIS who sequentially underwent CT and MTB between April 2016 and July 2021. These were grouped into training, testing, and external validation cohorts. Thrombus-extracted radiomic features and basic information were gathered to construct a machine learning model to predict CE stroke. The radiological characteristics and basic information were used to build a routine radiological model. A combined radiomics and radiological features model was also developed. The performances of all models were evaluated and compared in the validation cohort. A histological analysis helped further assess the proposed model in all patients.

RESULTS

The radiomics model yielded an area under the curve (AUC) of 0.838 (95% confidence interval [CI], 0.771-0.891) for predicting CE stroke in the validation cohort, significantly higher than the radiological model (AUC, 0.713; 95% CI, 0.636-0.781; p = 0.007) but similar to the combined model (AUC, 0.855; 95% CI, 0.791-0.906; p = 0.14). The thrombus radiomic features achieved stronger correlations with red blood cells (|r_max|, 0.74 vs. 0.32) and fibrin and platelet (|r_max|, 0.68 vs. 0.18) than radiological characteristics.

CONCLUSION

The proposed CT-based radiomics model could reliably predict CE stroke in AIS, performing better than the routine radiological method.

KEY POINTS

• Admission CT imaging could offer valuable information to identify the acute ischemic stroke source by radiomics analysis. • The proposed CT imaging-based radiomics model yielded a higher area under the curve (0.838) than the routine radiological method (0.713; p = 0.007). • Several radiomic features showed significantly stronger correlations with two main thrombus constituents (red blood cells, |r_max|, 0.74; fibrin and platelet, |r_max|, 0.68) than routine radiological characteristics.

Emergent Management of Tandem Occlusions in Anterior Circulation Stroke: A Single-Centre Experience

OBJECTIVE

For anterior circulation tandem occlusions, the optimal management strategy for extracranial carotid lesions is controversial. We aimed to compare the efficacy and safety of acute stenting (AS) with balloon angioplasty (BA) only.

METHODS

Clinical data were collected from 98 patients with anterior circulation tandem occlusion who underwent endovascular treatment at our center. Of these patients, 64 and 34 were assigned to the AS and BA groups, respectively. The clinical characteristics and outcome data of the 2 groups were analyzed and compared.

RESULTS

The proportion of patients with good outcomes was 59.2%. The AS group had a higher rate of successful recanalization (98.4% vs. 82.4%, P = 0.007) and a lower rate of occlusion of the responsible vessel at 90 days (14.1% vs. 32.4%, P = 0.039) than the BA group. The AS group was also significantly better than the BA group in terms of good outcomes (67.2% vs. 44.1%, P = 0.027), but there was no significant difference between the 2 groups in terms of 90-day mortality (6.3% vs. 8.8%, P = 0.691) and asymptomatic intracranial hemorrhage (6.3% vs. 5.9%, P = 1.000). Lower baseline National Institutes of Health Stroke Scale scores were associated with good outcomes (P < 0.001), and the presence of symptomatic intracranial hemorrhage was associated with 90-day mortality (P = 0.003).

CONCLUSIONS

Acute stent placement in patients with acute ischemic stroke due to anterior circulation tandem occlusion may have a better outcome than BA alone, and the safety of both approaches is comparable.

Crossed Cerebellar Diaschisis Worsens the Clinical Presentation in Acute Large Vessel Occlusion

INTRODUCTION

Initial NIHSS in anterior large vessel occlusion (LVO) correlates partially with the hypoperfusion volume. We aimed at assessing the contribution of crossed cerebellar diaschisis (CCD) from the hypoperfused territory on LVO initial clinical deficit.

METHODS

CCD was retrospectively identified by brain CT perfusion imaging (CTP) in patients with anterior LVO treated by mechanical thrombectomy from January 2017 to July 2021. CCD was defined by CTP parameter alteration in the contralateral cerebellar hemisphere to the LVO. NIHSS, clinical/perfusion variables, and CCD were included in regression models to assess their interrelationships.

RESULTS

206 patients were included. CCD was present in 90 patients (69%). NIHSS scores were higher on admission and at stroke discharge among patients with CCD (17.90 ± 6.1 vs. 11.4 ± 8.4, p < 0.001; 9.6 ± 7.7 vs. 6.6 ± 7.9, p = 0.049; respectively). Patients with a CCD had higher stroke volumes (118.2 ± 60.3 vs. 69.3 ± 59.7, p < 0.001) and lower rate of known atrial fibrillation (22% vs. 41%, p = 0.021). On multivariable logistic regression, CCD independently worsened the initial NIHSS (OR 4.85 [2.37-7.33]; p < 0.001).

CONCLUSION

CCD is found in 69% of LVO on admission CTP, correlates with stroke volumes, and independently worsens initial NIHSS.

Malignant Middle Cerebral Artery Infarction during Early versus Late Endovascular Treatment in Acute Ischemic Stroke

INTRODUCTION

Endovascular treatment (EVT) performed in the early time window has been shown to decrease the incidence of malignant middle cerebral artery infarction (MMI). However, the incidence of MMI in patients undergoing EVT during the late time window is unclear. This study aimed to investigate the prevalence of MMI in patients undergoing late EVT and compare it with that in patients undergoing early EVT.

METHODS

We retrospectively analyzed consecutive patients with anterior large vessel occlusion stroke who underwent EVT at Xuanwu Hospital between January 2013 and June 2021. Eligible patients were divided into early EVT (within 6 h) and late EVT (6-24 h) groups according to the time from their stroke onset to puncture and compared. The occurrence of MMI post-EVT was the primary outcome.

RESULTS

A total of 605 patients were recruited, of whom 300 (50.4%) underwent EVT within 6 h and 305 (49.6%) underwent EVT within 6-24 h. A total of 119 patients (19.7%) developed MMI. 68 patients (22.7%) in the early EVT group and 51 patients (16.7 %) in the late EVT group developed MMI (p = 0.066). After adjusting for covariate variables, late EVT was independently associated with a lower incidence of MMI (odds ratio, 0.404; 95% confidence interval, 0.242-0.675; p = 0.001).

CONCLUSION

MMI is not an uncommon phenomenon in the modern thrombectomy era. Compared with the early time window, patients selected by stricter radiological criteria to undergo EVT in the late time window are independently associated with a lower incidence of MMI.

NT-proBNP Levels and Collateral Circulation Status in Patients with Acute Ischemic Stroke

Methods

In this study, 326 hospitalized patients with acute anterior circulation ischemic stroke (AACIS) were included. A comparison of the clinical characteristics of those with and without AF was conducted. The Spearman rank correlation was used for the correlation analysis of plasma NT-proBNP level, regional leptomeningeal collateral (rLMC) score, and computed tomography perfusion (CTP) status in the AF and non-AF groups. An analysis of multivariate linear regression was used to determine how plasma NT-proBNP level, rLMC score, and CTP status influenced the score on the NIHSS.

Results

There was a greater plasma NT-proBNP level in the AF group compared with the non-AF group, an increased CTP volume (including CTP ischemic volume, CTP infarct core volume, and CTP ischemic penumbra volume (P = 0.002)), higher NIHSS score on admission, and lower rLMC score (P < 0.001 for the remaining parameters). A negative correlation exists between plasma NT-proBNP level and rLMC score (r = -0.156, P = 0.022), but a positive correlation exists between plasma NT-proBNP level and both CTP ischemic volume and CTP infarct core volume (r = 0.148, P = 0.003) in the AF group, but not in the non-AF group. Multivariate linear regression analysis demonstrated that NT-proBNP, CTP ischemic penumbra volume, and rLMC score were associated with NIHSS score, and NT-proBNP was positively associated with NIHSS scores (95% confidence interval (CI), 0.000-0.002; P = 0.004) in the AF group, whatever in the unadjusted model or adjusted models, but not in the nonlarge artery atherosclerosis (LAA) group.

Conclusion

In AACIS patients with AF, NT-proBNP level negatively correlated with collateral status, positively with CTP ischemic volume, and positively with NIHSS score.

Delayed neurological improvement after endovascular treatment for acute large vessel occlusion: data from ANGEL-ACT registry

BACKGROUND

A subgroup of patients with acute large vessel occlusion (ALVO) may experience delayed neurological improvement (DNI) after endovascular treatment (EVT). Our study aimed to investigate the incidence and independent predictors of DNI in patients with ALVO after EVT.

METHODS

We selected subjects from ANGEL-ACT Registry. The definition of DNI is patients with ALVO who did not experience early neurological improvement (ENI) despite complete recanalization after EVT. These patients achieved a 90-day favorable outcome assessed by a modified Rankin Scale (mRS) score. We defined ENI as a ≥ 4-point decrease in the National Institutes of Health Stroke Scale (NIHSS) between baseline and 24 h or NIHSS of 0 or 1 at 24 h, with complete recanalization after EVT. We performed logistic regression analyses to determine the independent predictors of DNI.

RESULTS

Among the 1056 enrolled patients, 406 (38.4%) did not experience ENI. 106 (26.1%) patients without ENI achieved DNI. On Multivariate analysis, lower admission NIHSS score (odds ratio [OR] = 1.17,95% confidence interval [CI]: 1.11-1.23, P < 0.001), underlying ICAD (OR = 2.03, 95% CI: 1.07-3.85, P = 0.029) and absence of general anesthesia (OR = 2.13, 95% CI: 1.24-3.64, P = 0.006) were independent predictors of DNI.

CONCLUSION

DNI occurred in 26.1% of patients with ALVO who did not experience ENI after EVT. Our study identified several independent predictors of DNI that should be highly considered in daily clinical practice to improve ALVO management.

Prediction of intracranial atherosclerotic acute large vessel occlusion by severe hypoperfusion volume growth rate

BACKGROUND AND PURPOSE

We aimed to investigate whether the time elapsed from stroke onset to imaging (OTI) combined with the parameters generated by automated computed tomography perfusion (CTP) could predict large vessel occlusion (LVO) patients with underlying intracranial atherosclerotic disease (ICAD) before endovascular treatment (EVT).

METHODS

We performed a prospective cohort of LVO patients with automated CTP before EVT from two comprehensive stroke centers. Severe hypoperfusion volume growth rate was defined as the Time-to-Maximum (Tmax) > 10s divided by OTI. We performed receiver operating characteristic analyses to assess the ICAD prediction performance of all the automated CTP parameters, Delong test to compare the area under the curve (AUC) of severe hypoperfusion volume growth rate with the AUC of the other parameters, and logistic regression analysis to find the independent predictors of LVO with underlying ICAD.

RESULTS

Of the 204 enrolled LVO patients, 95 ICAD patients and 109 non-ICAD patients were identified. The AUC of severe hypoperfusion volume growth rate was 0.86 (95% confidence interval [CI] 0.81 - 0.91, P < 0.001), the cut-off value with the highest Youden Index was ≤ 11.2 mL/h (sensitivity, 78.95%; specificity, 77.06%; accuracy 77.94%), which was larger than the other parameters except for hypoperfusion intensity ratio (HIR) (All P for Delong test < 0.05). Atrial fibrillation (odds ratio [OR]: 0.09, 95%CI: 0.03 - 0.26, P < 0.001), admission ASPECTS (1-point increased OR: 1.25, 95%CI: 1.03 - 1.53, P = 0.024), and severe hypoperfusion volume growth rate (1 mL/h increased OR: 0.94, 95%CI: 0.90 - 0.98, P = 0.003) were associated with underlying ICAD independently.

CONCLUSIONS

Severe hypoperfusion volume growth rate showed the best performance for LVO with underlying ICAD prediction. Future larger studies for external validation are needed.

Balloon Angioplasty Combined with Tirofiban as a First-Line Rescue Treatment After Failed Mechanical Thrombectomy for Middle Cerebral Artery Occlusion with Underlying Atherosclerosis

OBJECTIVE

The standard rescue modality for patients with intracranial atherosclerotic stenosis after failed mechanical thrombectomy (MT) is not well established. We evaluated the safety and efficacy of balloon dilation in combination with tirofiban as the first-line salvage therapy when MT failed in these patients.

METHODS

We retrospectively analyzed the records of 47 patients admitted between January 2018 and June 2021, with middle cerebral artery atherosclerotic occlusion, who underwent balloon angioplasty in combination with tirofiban as the first-line salvage therapy after the failure of MT. The recanalization outcome, procedure-related complications, symptomatic intracranial hemorrhage, and functional outcome at 90 days were reviewed.

RESULTS

Recanalization with a modified Thrombolysis in Cerebral Infarction grade of 2b-3 was achieved in 41 (87.2%) of the 47 patients. Acute stents were deployed in another 6 patients who did not achieve successful re-perfusion after balloon angioplasty. Successful recanalization was achieved in 3 of them. One patient (2.1%, 1/47) experienced re-occlusion several days later due to the withdrawal of antiplatelet therapy for parenchymal hematoma. Seven patients (14.9%, 7/47) underwent stent angioplasty in the stable stage (range: 1-2 months) because severe residual stenosis was detected on follow-up imaging. There was only one event of periprocedural complication, namely ectopic migration of emboli. The good functional outcome rate was 55.3% (26/47), without the events of symptomatic intracranial hemorrhage and mortality.

CONCLUSIONS

Balloon angioplasty in combination with tirofiban is safe and effective for middle cerebral artery atherosclerotic occlusion after the failure of MT.

Identification of magnetic resonance imaging features for the prediction of unrecognized atrial fibrillation in acute ischemic stroke

Background and purpose

The early identification of cardioembolic stroke is critical for the early initiation of anticoagulant treatment. However, it can be challenging to identify the major cardiac source, particularly since the predominant source, paroxysmal atrial fibrillation (AF), may not be present at the time of stroke. In this study, we aimed to evaluate imaging predictors for unrecognized AF in patients with acute ischemic stroke.

Methods

We performed a cross-sectional analysis of data and magnetic resonance imaging (MRI) scans from two prospective cohorts of patients who underwent serial 12-lead electrocardiography and 24-h Holter monitoring to detect unrecognized AF. The imaging patterns in diffusion-weighted imaging and imaging characteristics were assessed and classified. A logistic regression model was used to identify predictive factors for newly detected AF in patients with acute ischemic stroke.

Results

A total of 734 patients were recruited for analysis, with a median age of 72 (interquartile range: 65–79) years and a median National Institutes of Health Stroke Scale score of 4 (interquartile range: 2–6). Of these patients, 64 (8.7%) had newly detected AF during the follow-up period. Stepwise multivariate logistic regression revealed that age ≥75 years [adjusted odds ratio (aOR) 5.66, 95% confidence interval (CI) 2.98–10.75], receiving recombinant tissue plasminogen activator treatment (aOR 4.36, 95% CI 1.65–11.54), congestive heart failure (aOR 6.73, 95% CI 1.85–24.48), early hemorrhage in MRI (aOR 3.62, 95% CI 1.52–8.61), single cortical infarct (aOR 6.49, 95% CI 2.35–17.92), and territorial infarcts (aOR 3.54, 95% CI 1.06–11.75) were associated with newly detected AF. The C-statistic of the prediction model for newly detected AF was 0.764.

Conclusion

Initial MRI at the time of stroke may be useful to predict which patients have cardioembolic stroke caused by unrecognized AF. Further studies are warranted to verify these findings and their application to high-risk patients.

Cerebral Collateral Circulation in the Era of Reperfusion Therapies for Acute Ischemic Stroke

Clinical outcomes of patients with acute ischemic stroke depend in part on the extent of their collateral circulation. A good collateral circulation has also been associated with greater benefit of intravenous thrombolysis and endovascular treatment. Treatment decisions for these reperfusion therapies are increasingly guided by a combination of clinical and imaging parameters, particularly in later time windows. Computed tomography and magnetic resonance imaging enable a rapid assessment of both the collateral extent and cerebral perfusion. Yet, the role of the collateral circulation in clinical decision-making is currently limited and may be underappreciated due to the use of rather coarse and rater-dependent grading methods. In this review, we discuss determinants of the collateral circulation in patients with acute ischemic stroke, report on commonly used and emerging neuroimaging techniques for assessing the collateral circulation, and discuss the therapeutic and prognostic implications of the collateral circulation in relation to reperfusion therapies for acute ischemic stroke.

BNP on Admission Combined with Imaging Markers of Multimodal CT to Predict the Risk of Cardioembolic Stroke

Background

The aim of the study was to find the potential roles of B-type natriuretic peptide (BNP) and imaging markers on distinguishing cardioembolic (CE) stroke from non-CE stroke, so as to provide useful information for making individualized endovascular treatment (EVT) plan for the patients with acute ischemic stroke (AIS).

Methods

The patients with unilateral anterior circulation large vessel occlusion who underwent EVT between March 2016 and December 2021 were analyzed in this study, retrospectively. The risk factors, laboratory test indicators, imaging parameters, and other factors were compared between the CE group and non-CE group. Logistic regression was used to analyze the risk factors of CE stroke. ROC curves were used to assess the values of different parameters on distinguishing CE stroke from non-CE stroke. The relationships between BNP and imaging parameters were assessed using the Spearman correlation analysis.

Results

160 patients were enrolled in the study and divided into the CE group (n = 66) and non-CE group (n = 94). BNP (odds ratio (OR) = 1.004; 95% CI, 1.001-1.009; p = 0.038), MMR (OR = 0.736; 95% CI, 0.573-0.945; p = 0.016), NIHSS (OR = 1.150; 95% CI, 1.022-1.294; p = 0.020), and AF (OR = 556.968; 95% CI, 51.739-5995.765; p < 0.001) were the independent predictive factors of CE stroke. The area under the curve (AUC) of BNP and mismatch ratio (MMR) were 0.846 (95% CI (0.780-0.898), p < 0.001) and 0.636 (95% CI (0.633-0.779), p < 0.001), respectively. The cut-off value of BNP was 249.23 pg/mL with the sensitivity of 74.24% and the specificity of 82.98%. BNP combined with MMR improved the predictive value for CE stroke. The AUC of the combination was 0.858 with the sensitivity of 84.85% and the specificity of 73.40%. BNP was correlated with 4D CTA collateral score, MMR, clot burden score, final infarct volume, infarct core volume, and ischemic penumbra volume (all, p < 0.05).

Conclusion

BNP on admission combined with MMR is valuable for the risk prediction of CE stroke, which will promote the further screening of the high-risk patients with CE stroke and provide more diagnostic information for clinicians.

Acute Stroke and Atrial Fibrillation: Risk of Incorrect NOAC Dosage When Estimating Renal Function From Plasma Creatinine Only

Background

Cardioembolic stroke (CS) due to atrial fibrillation (AF) bears a high risk of unfavorable outcome. Treatment with a non-vitamin K antagonist oral anticoagulant (NOAC) reduces this risk. NOAC dosage occurs on a thin line during the acute phase of the stroke unit when the patient is threatened by both recurrent CS and a hemorrhagic stroke. It is often adapted to renal function—usually glomerular filtration rate (GFR)—to prevent both under- and overdosing. This study investigates the hypothetical risk of incorrect NOAC dosage after acute stroke when relying on plasma creatinine alone in comparison to a more exact renal function assessment including urine collection.

Methods

In a cohort study on consecutive 481 patients treated in a stroke unit with acute stroke and AF, the GFR estimated from plasma creatinine (eGFR) was compared to concurrent creatinine clearance measurement (CrCl) from urine collection regarding the hypothetically derived NOAC dosage.

Results

The risk of incorrect dosage (mean, 95% confidence interval) was 6.9% (4.8–9.5), 26% (23–31), 38% (33–42), and 20% (16–23) for apixaban, dabigatran, edoxaban, and rivaroxaban, respectively. The overall risk for incorrect dosage of any NOAC was 23% (21–25). Thresholds for age and admission eGFR were optimized to achieve an overall risk below 5% by additional CrCl measurements in selected patients (apixaban <36 ml/min and any age, dabigatran <75 ml/min and >70 y, edoxaban >36 ml/min and >58 y, rivaroxaban <76 ml/min and >75 y, any NOAC <81 ml/min and >54 y). The resulting portion of patients requiring an additional CrCl measurement was 10, 60, 80, 55, and 65% for apixaban, dabigatran, edoxaban, rivaroxaban, and any NOAC, respectively.

Conclusions

There is a considerable risk of incorrect NOAC dosage in patients with acute CS treated in a stroke unit that can be lowered by targeted CrCl measurements in selected patients.

Hypoperfusion Intensity Ratio is Associated with Stroke Mechanism in Patients Undergoing Mechanical Thrombectomy

BACKGROUND

Hypoperfusion Intensity Ratio (HIR), defined as Tmax >10s/Tmax >6s on computed tomography perfusion (CTP), and stroke mechanisms have been independently correlated with angiographic collaterals and patient outcomes. Slowly developing atherosclerotic stenosis may foster collateral development, whereas cardioembolic occlusion may occur before collaterals mature. We hypothesized that favorable HIR is associated with large artery atherosclerosis (LAA) stroke mechanism and good clinical outcome.

METHODS

Retrospective study of consecutive endovascularly-treated stroke patients with intracranial ICA or MCA M1/M2 occlusions, who underwent CTP before intervention, between January 2018 and August 2021. Patients were dichotomized into LAA+ or LAA- based on presence of LAA on angiography. HIR was dichotomized into favorable (HIR+) or unfavorable (HIR-) groups based on published thresholds. Good early outcome was defined as discharge mRS of 0-2. Bivariate and multivariable logistic regression were performed.

RESULTS

143 patients met inclusion. 21/143 were LAA+ (15%) and 65/143 (45%) were HIR+. HIR+ was significantly more frequent in LAA+ patients (67% vs. 42%, p= 0.035). Controlling for demographics, stroke severity, imaging findings, and medical comorbidities, LAA+ remained independently associated with HIR+ (OR 5.37 [95% CI 1.43 - 20.14]; p=0.013) as did smaller infarction core volume (<30 mL of CBF <30%: OR 7.92 [95% CI 2.27 - 27.64]; p = 0.001). HIR+ was not associated with good clinical outcome.

CONCLUSIONS

Large artery atherosclerosis was independently associated with favorable HIR in patients undergoing mechanical thrombectomy. While favorable HIR was associated with smaller pre-treatment core infarcts, reflecting more robust collaterals, it was not associated with good clinical outcome.

Leukoaraiosis Distribution and Cerebral Collaterals: A Systematic Review and Meta-Analysis

Background and Objective

Microvascular failure might result in the collapse of cerebral collaterals. However, controversy remains regarding the role of leukoaraiosis (LA) in collateral recruitment. We, therefore, performed a systematic review and meta-analysis of the association between LA and cerebral collaterals.

Methods

Ovid Medline, PubMed, Embase, Web of Science, and three Chinese databases were searched from inception to August 2021. Two types of cerebral collaterals, including Circle of Willis (CoW) and leptomeningeal collaterals (LC), were investigated separately. Random effect models were used to calculate the pooled odds ratio (OR). Meta-regression and subgroup analyses were performed to explore the potential sources of heterogeneity.

Results

From 14 studies (n = 2,451) that fulfilled our inclusion criteria, data from 13 could be pooled for analysis. Overall, there was a significant association between severe LA and incomplete CoW (pooled OR 1.66, 95% CI 1.18–2.32, p = 0.003), with low heterogeneity (I² = 5.9%). This association remained significant in deep LA (pooled OR 1.48, 95% CI 1.04–2.11, p = 0.029, I² = 0), but not periventricular LA. Similarly, there was a significant association between LA and LC (pooled OR 1.73, 95% CI 1.03–2.90, p = 0.037), but with high heterogeneity (I² = 67.2%). Meta-regression indicated a negative association of sample size with the effect sizes (p = 0.029). In addition, most of the studies (7/9) included into the analysis of the relationship of severe LA with poor LC enrolled subjects with large vessel occlusion stroke, and this relationship remained significant when pooling the seven studies, but with high heterogeneity.

Conclusion

Severe LA is associated with a higher prevalence of poor collaterals. This association is robust for CoW but weak for LC. Further studies are required to explore the underlying mechanisms.

Association of Systolic Blood Pressure and Cerebral Collateral Flow in Acute Ischemic Stroke by Stroke Subtype

Background and Purpose

Collateral flow in acute ischemic stroke is known as a predictor of treatment outcome and long-term prognosis. However, factors determining the initial collateral flow remain unclear. We investigated factors related to collateral flow in patients with acute ischemic stroke caused by large vessel occlusion (AIS-LVO) and further analyzed the results according to stroke etiology.

Methods

This was a retrospective study using prospective stroke registry data from a single university hospital from October 2014 to May 2021. AIS-LVO with middle cerebral artery M1 occlusion identified by pre-treatment multiphasic computed tomography angiography was included. Collateral flow score was graded on a 6-point ordinal scale according to pial arterial filling.

Results

A total of 74 patients [cardioembolism (CE): 57; large artery atherosclerosis (LAA): 17] was included. The mean age of all patients was 72.2 ± 11.7 years, and 37.8 % (n = 28) were men. Multivariate regression analysis showed that initial SBP [odds ratio (OR): 0.994; 95% confidence interval (CI): 0.990–0.998; p = 0.002] and stroke etiology (OR: 0.718; 95% CI: 0.548–0.940; p = 0.019) were independent factors of the collateral flow grade. Collateral flow grade was independently associated with initial SBP in the CE group (OR: 0.993; 95% CI: 0.989–0.998; p = 0.004) but not in the LAA group (OR: 0.992; 95% CI: 0.980–1.004; p = 0.218). Initial SBP was significantly correlated with NIHSS score in the CE group but not in the LAA group (r²= 0.091, p = 0.023; r² = 0.043, p = 0.426, respectively).

Conclusions

Elevated initial SBP was associated with poor cerebral collateral flow and more severe symptoms in the CE group, but not in the LAA group in patients with AIS-LVO. These findings suggest differential effects of initial SBP elevation on collateral flow by stroke subtypes.

Association of Stroke Subtype With Hemorrhagic Transformation Mediated by Thrombectomy Pass: Data From the ANGEL-ACT Registry

BACKGROUND

The role of stroke etiology subtype in patients with acute large vessel occlusion on the occurrence of hemorrhagic transformation (HT) after endovascular treatment is poorly studied, and which factors mediate their relationship remains largely unknown. We utilized nationwide registry data to explore the association of stroke subtype (cardioembolism versus large artery atherosclerosis) with HT and to identify the possible mediators.

METHODS

A total of 1015 subjects were selected from the ANGEL-ACT registry (Endovascular Treatment Key Technique and Emergency Work Flow Improvement of Acute Ischemic Stroke)-a prospective consecutive cohort of acute large vessel occlusion patients undergoing endovascular treatment at 111 hospitals in China between November 2017 and March 2019-and divided into large artery atherosclerosis (n=538) and cardioembolism (n=477) according to the Trial of ORG 10172 in Acute Stroke Treatment criteria. The types of HT included any intracerebral hemorrhage (ICH), parenchymal hematoma, and symptomatic ICH within 24 hours after endovascular treatment. The association between stroke subtype and HT was analyzed using a logistic regression model. Mediation analysis was done to assess how much of the effect of stroke subtype on HT was mediated through the identified mediators.

RESULTS

Stroke subtype (cardioembolism versus large artery atherosclerosis) was associated with increased risk of any ICH (29.8% versus 16.5%; odds ratio, 2.03 [95% CI, 1.22-3.36]), parenchymal hematoma (14.3% versus 5.4%; odds ratio, 2.90 [95% CI, 1.38-6.13]), and symptomatic ICH (9.9% versus 4.7%; odds ratio, 2.59 [95% CI, 1.09-6.16]) after adjustment for potential confounders. The more thrombectomy passes in cardioembolism patients had a significant mediation effect on the association of stroke subtype with increased risk of HT (any ICH, 15.9%; parenchymal hematoma, 13.4%; symptomatic ICH, 14.2%, respectively).

CONCLUSIONS

Stroke subtype is an independent risk factor for HT within 24 hours following endovascular treatment among acute large vessel occlusion patients. Mediation analyses propose that stroke subtype contributes to HT partly through thrombectomy pass, suggesting a possible pathomechanistic link.

Integrative cerebral blood flow regulation in ischemic stroke

Optimizing cerebral perfusion is key to rescuing salvageable ischemic brain tissue. Despite being an important determinant of cerebral perfusion, there are no effective guidelines for blood pressure (BP) management in acute stroke. The control of cerebral blood flow (CBF) involves a myriad of complex pathways which are largely unaccounted for in stroke management. Due to its unique anatomy and physiology, the cerebrovascular circulation is often treated as a stand-alone system rather than an integral component of the cardiovascular system. In order to optimize the strategies for BP management in acute ischemic stroke, a critical reappraisal of the mechanisms involved in CBF control is needed. In this review, we highlight the important role of collateral circulation and re-examine the pathophysiology of CBF control, namely the determinants of cerebral perfusion pressure gradient and resistance, in the context of stroke. Finally, we summarize the state of our knowledge regarding cardiovascular and cerebrovascular interaction and explore some potential avenues for future research in ischemic stroke.

The Safety and Efficacy of Endovascular Treatment in Acute Ischemic Stroke Patients Caused by Large-Vessel Occlusion with Different Etiologies of Stroke: Data from ANGEL-ACT Registry

This study aimed to investigate the safety and efficacy of endovascular treatment (EVT) in acute ischemic stroke (AIS) patients caused by large-vessel occlusion (LVO) with different etiologies of stroke. A total of 928 AIS patients were assigned into intracranial atherosclerotic stenosis (ICAS)-LVO, cardioembolic (CE)-LVO, and artery to artery embolism (ATA)-LVO groups. The safety and efficacy endpoints were symptomatic intracranial hemorrhage (SICH) at 24 h after EVT, 90-day favorable outcomes (modified Rankin Scale (mRS) of 0-2), successful recanalization (modified thrombolysis in cerebral infarct (mTICI) 2b/3), and complete recanalization (mTICI 3). The logistic regression analysis was used to determine the associations between the safety and efficacy endpoints. There were 305 (32.9%), 535 (57.6%), and 88 (9.5%) patients in ICAS-LVO, CE-LVO, and ATA-LVO groups, respectively. No significant difference was found in the 90-day mRS and successful recanalization among the three groups. However, compared with the ICAS-LVO group, complete recanalization rate was higher in the CE-LVO (adjusted odds ratio, 4.50; 95% confidence interval (CI), 2.37-8.56) and ATA-LVO groups (aOR, 2.43; 95% CI, 1.16-5.10). The results of subgroup analysis showed a significant association between CE-LVO stroke etiology and complete recanalization in the age population < 65 years old (aOR, 14.33; 95% CI, 4.39-46.79, P = 0.019). Functional outcomes were similar among different etiologies of stroke. CE-LVO and ATA-LVO could be related to a higher rate of complete recanalization, and there was a trend of the increased risk of parenchymal hemorrhage in the CE-LVO group.

The Hyperdense middle cerebral artery sign is associated with poor leptomeningeal collaterals in acute ischemic stroke: a retrospective study

Background

The hyperdense middle cerebral artery sign (HMCAS) is an early radiological marker to provide an early diagnosis and to identify ischemia. As reported, HMCAS is associated with heavy clot burden. Moreover, a heavy clot burden may cause obstruction of the orifices of arteries for leptomeningeal collateral flows and can lead to severe clinical conditions. However, the direct relationship between HMCAS and collateral flows remains unclear. Therefore, we explored the association between HMCAS and leptomeningeal collaterals in patients with acute ischemic stroke.

Methods

Consecutive ischemic stroke patients were enrolled from January 2015 to April 2021. HMCAS appearance and collateral status were detected by multimodal computed tomography at admission. Logistic regression analyses helped to identify the association between HMCAS, collateral flows and stroke severity.

Results

In 494 included patients, 180 (36.4%) presented with HMCAS. Ipsilateral collaterals were not seen or less prominent in patients with HMCAS (P < 0.001). The HMCAS appearance was significantly associated with less collaterals (odds ratio 5.17, 95% confidence interval 3.27-8.18, P < 0.001), internal carotid artery + M1/M1 occlusion, the initial stroke severity and follow-up outcomes. Subgroup analyses further confirmed HMCAS as an indicator of poor collaterals in ischemic stroke (all P values < 0.05).

Conclusions

HMCAS is associated with poor leptomeningeal collaterals, the stroke severity and a poor neurological outcome. Therefore, the HMCAS appearance can act as an early warning sign for healthcare professionals to be alert for poor collateral flows and poor neurological outcomes in ischemic stroke patients with middle cerebral artery occlusion.

Cerebrovascular Collateral Integrity in Pediatric Large Vessel Occlusion: Analysis of the Save ChildS Study

BACKGROUND AND OBJECTIVES

Robust cerebrovascular collaterals in adult patients with large vessel occlusion stroke have been associated with longer treatment windows, better recanalization rates, and improved outcomes, but the role of collaterals in pediatric stroke is not known. The primary aim was to determine whether favorable collaterals correlated with better radiographic and clinical outcomes in children with ischemic stroke who underwent thrombectomy.

METHODS

This study analyzed a subset of children enrolled in SaveChildS, a retrospective, multicenter, observational cohort study of 73 pediatric patients with stroke who underwent thrombectomy between 2000 and 2018 at 27 US and European centers. Included patients had baseline angiographic imaging and follow-up modified Rankin Scale scores available for review. Posterior circulation occlusions were excluded. Cerebrovascular collaterals were graded on acute neuroimaging by 2 blinded neuroradiologists according to the Tan collateral score, in which favorable collaterals are defined as >50% filling and unfavorable collaterals as <50% filling distal to the occluded vessel. Collateral status was correlated with clinical and neuroimaging characteristics and outcomes. Between-group comparisons were performed with the Wilcoxon rank-sum test for continuous variables or Fisher exact test for binary variables.

RESULTS

Thirty-three children (mean age 10.9 [SD ±4.9]) years were included; 14 (42.4%) had favorable collaterals. Median final stroke volume as a percent of total brain volume (TBV) was significantly lower in patients with favorable collaterals (1.35% [interquartile range (IQR) 1.14%-3.76%] vs 7.86% [IQR 1.54%-11.07%], p = 0.049). Collateral status did not correlate with clinical outcome, infarct growth, or final Alberta Stroke Program Early CT Score (ASPECTS) in our cohort. Patients with favorable collaterals had higher baseline ASPECTS (7 [IQR 6-8] vs 5.5 [4-6], p = 0.006), smaller baseline ischemic volume (1.57% TBV [IQR 1.09%-2.29%] vs 3.42% TBV [IQR 1.26%-5.33%], p = 0.035), and slower early infarct growth rate (2.4 mL/h [IQR 1.5-5.1 mL/h] vs 10.4 mL/h [IQR 3.0-30.7 mL/h], p = 0.028).

DISCUSSION

Favorable collaterals were associated with smaller final stroke burden and slower early infarct growth rate but not with better clinical outcome in our study. Prospective studies are needed to determine the impact of collaterals in childhood stroke.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that in children with ischemic stroke undergoing thrombectomy, favorable collaterals were associated with improved radiographic outcomes but not with better clinical outcomes.

Effect of stroke etiology on endovascular thrombectomy with or without intravenous alteplase: a subgroup analysis of DIRECT-MT

BACKGROUND

Stroke etiology might influence the clinical outcomes in patients with large vessel occlusion receiving endovascular treatment (EVT) with or without thrombolysis.

OBJECTIVE

To examine whether stroke etiology resulted in different efficacy and safety in patients treated with EVT-alone or EVT preceded by intravenous alteplase (combined therapy).

METHODS

We assessed the efficacy and safety of treatment strategy based on prespecified stroke etiology, cardioembolism (CE), large-artery atherosclerosis (LAA), and undetermined cause (UC) for patients enrolled in the DIRECT-MT trial. The primary outcome was the modified Rankin Scale (mRS) score at 90 days. Multivariate ordinal logistic regression analysis was used to calculate the adjusted common OR for a shift of better mRS score for EVT-alone versus combined therapy. A term was entered to test for interaction.

RESULTS

In this study, 656 patients were grouped into three prespecified stroke etiologic subgroups. The adjusted common ORs for improvement in the 90-day ordinal mRS score with EVT-alone were 1.2 (95% CI 0.8 to 1.8) for CE, 1.6 (95% CI 0.8 to 3.3) for LAA, and 0.8 (95% CI 0.5 to 1.3) for UC. Compared with CE, EVT-alone was more likely to result in an mRS score of 0-1 (p_interaction=0.047) and extended Thrombolysis in Cerebral Infarction ≥2b (p_interaction=0.041) in the LAA group. The differences in mortality and symptomatic intracranial hemorrhage within 90 days were not significant between the subgroups (p＞0.05).

CONCLUSIONS

The results did not support the hypothesis that a specific treatment strategy based on stroke etiology should be used for patients with large vessel occlusion (NCT03469206).

Reduced Leukoaraiosis, Noncardiac Embolic Stroke Etiology, and Shorter Thrombus Length Indicate Good Leptomeningeal Collateral Flow in Embolic Large-Vessel Occlusion

BACKGROUND AND PURPOSE

Acute leptomeningeal collateral flow is vital for maintaining perfusion to penumbral tissue in acute ischemic stroke caused by large-vessel occlusion. In this study, we aimed to investigate the clinically available indicators of leptomeningeal collateral variability in embolic large-vessel occlusion.

MATERIALS AND METHODS

Among prospectively registered consecutive patients with acute embolic anterior circulation large-vessel occlusion treated with thrombectomy, we analyzed 108 patients admitted from January 2015 to December 2019 who underwent evaluation of leptomeningeal collateral status on pretreatment CTA. Clinical characteristics, extent of leukoaraiosis on MR imaging, embolic stroke subtype, time of imaging, occlusive thrombus characteristics, presenting stroke severity, and clinical outcome were collected. The clinical indicators of good collateral status (>50% collateral filling of the occluded territory) were analyzed using multivariate logistic regression analysis.

RESULTS

Good collateral status was present in 67 patients (62%) and associated with independent functional outcomes at 3 months. Reduced leukoaraiosis (total Fazekas score, 0-2) was positively related to good collateral status (OR, 9.57; 95% CI, 2.49-47.75), while the cardioembolic stroke mechanism was inversely related to good collateral status (OR, 0.17; 95% CI, 0.02-0.87). In 82 patients with cardioembolic stroke, shorter thrombus length (OR, 0.91 per millimeter increase; 95% CI, 0.82-0.99) and reduced leukoaraiosis (OR, 5.79; 95% CI, 1.40-29.61) were independently related to good collateral status.

CONCLUSIONS

Among patients with embolic large-vessel occlusion, reduced leukoaraiosis, noncardiac embolism mechanisms including embolisms of arterial or undetermined origin, and shorter thrombus length in cardioembolism are indicators of good collateral flow.

Efficacy and safety of direct balloon angioplasty in the treatment of large atherosclerotic stroke

OBJECTIVE

Based on the unclear safety and effectiveness of direct balloon angioplasty as a first-line treatment for patients with acute ischemic stroke caused by large artery atherosclerosis (LAA), our paper would center on investigating the safety and effectiveness of this novel strategy.

PATIENTS AND METHODS

A consecutive series of acute ischemic stroke patients due to intracranial atherosclerosis and short thrombus who underwent thorough direct balloon angioplasty from October 2019 to March 2021 were enrolled. The primary end point included arterial recanalization (modified Thrombolysis in Cerebral Infarction [mTICI]: 2b-3), and 90-day functional independence (modified Rankin Scale[mRS]: 0-2). The secondary end point was symptomatic intracerebral hemorrhage (sICH) and perioperative restenosis and re-occlusion of offending vessel.

RESULTS

68 patients were included. Mean time from onset to groin puncture was 342.5 min and 50 min for groin puncture to successful recanalization. 61 (89.7%) patients achieved successful recanalization and 41 (60.3%) acquired functional independence. 11 (16.0%) patients experienced ICH and only 3 (4.4%) for sICH. 8 (11.8%) patients developed symptomatic restenosis or re-occlusion within seven days after the operation. In addition, 16 (23.5%) patients received rescue stenting and 3 (18.8%) of this subgroup appeared immediate intra-stent thrombosis.

CONCLUSION

Direct balloon angioplasty may be a safe and effective method for the treatment of stroke caused by intracranial large arteriosclerosis occlusion.

Stroke Aetiology and Collateral Status in Acute Ischemic Stroke Patients Receiving Reperfusion Therapy-A Meta-Analysis

BACKGROUND

The interplay between collateral status and stroke aetiology may be crucial in the evaluation and management of acute ischemic stroke (AIS). Our understanding of this relationship and its level of association remains sub-optimal. This study sought to examine the association of pre-intervention collateral status with stroke aetiology, specifically large artery atherosclerosis (LAA) and cardio-embolism (CE), in AIS patients receiving reperfusion therapy, by performing a meta-analysis.

METHODS

Relevant search terms were explored on Medline/PubMed, Embase and Cochrane databases. Studies were included using the following inclusion criteria: (a) patients aged 18 or above; (b) AIS patients; (c) patients receiving reperfusion therapy; (d) total cohort size of >20, and (e) qualitative or quantitative assessment of pre-intervention collateral status on imaging using a grading scale. Random-effects meta-analysis was performed to investigate the association of aetiology with pre-intervention collateral status, and forest plots of risk ratio (RR) were generated.

RESULTS

A meta-analysis was conducted on seven studies, with a cumulative cohort of 1235 patients, to assess the association of pre-intervention collateral status with stroke aetiology. Patients with LAA were associated significantly with an increased rate of good collaterals (RR 1.24; 95% CI 1.04-1.50; p = 0.020, z = 2.33). Contrarily, CE aetiology was associated significantly with a decreased rate of good collaterals (RR 0.83; 95% CI 0.71-0.98; p = 0.027, z = -2.213).

CONCLUSIONS

This study demonstrates that, in AIS patients receiving reperfusion therapy, LAA and CE aetiologies are associated significantly with collateral status.

Collateral estimation by susceptibility-weighted imaging and prediction of functional outcomes after acute anterior circulation ischemic stroke

To determine the value of susceptibility-weighted imaging (SWI) for collateral estimation and for predicting functional outcomes after acute ischemic stroke. To identify independent predictors of favorable functional outcomes, age, sex, risk factors, baseline National Institutes of Health Stroke Scale (NIHSS) score, baseline diffusion-weighted imaging (DWI) lesion volume, site of steno-occlusion, SWI collateral grade, mode of treatment, and successful reperfusion were evaluated by multiple logistic regression analyses. A total of 152 participants were evaluated. A younger age (adjusted odds ratio (aOR), 0.42; 95% confidence interval (CI) 0.34 to 0.77; P < 0.001), a lower baseline NIHSS score (aOR 0.90; 95% CI 0.82 to 0.98; P = 0.02), a smaller baseline DWI lesion volume (aOR 0.83; 95% CI 0.73 to 0.96; P = 0.01), an intermediate collateral grade (aOR 9.49; 95% CI 1.36 to 66.38; P = 0.02), a good collateral grade (aOR 6.22; 95% CI 1.16 to 33.24; P = 0.03), and successful reperfusion (aOR 5.84; 95% CI 2.08 to 16.42; P = 0.001) were independently associated with a favorable functional outcome. There was a linear association between the SWI collateral grades and functional outcome (P = 0.008). Collateral estimation using the prominent vessel sign on SWI is clinically reliable, as it has prognostic value.

Angioplasty alone versus acute stenting for acute tandem occlusions due to internal carotid artery atherosclerotic

OBJECTIVE

The aim of the study is to compare the efficacy and safety of angioplasty alone with acute stenting for acute tandem occlusions (TO) due to internal carotid artery atherosclerotic.

METHODS

We identified 112 patients who underwent an endovascular treatment (EVT) for acute tandem internal carotid artery occlusions from the prospectively maintained registries 5 comprehensive stroke centers. The study cohort included 75 patients with underlying atherosclerotic lesion of the extracranial internal carotid artery, forty-five in the balloon angioplasty (BA) alone group and 30 in the acute stenting (AS) group. Using propensity score matching analysis, forty-four patients were matched. Clinical characteristics and outcome data were compared between two groups.

RESULTS

The successful reperfusion immediately post procedure [72.7% (16/22) vs. 77.3% (17/22), P = 1.0] and 90-days good functional outcome [54.5% (12/22) vs. 59.1% (13/22), P = 0.761] were not significantly different between the BA group and AS group. There was also no significant difference in the rate of symptomatic intracranial hemorrhage [13.6% (3/22) vs. 9.1% (2/22), P = 1.00] and restenosis of ICA (>50%)[27.3% (6/22) vs. 22.7% (5/22), P = 0.728] between 2 groups. Patients in the BA group appear to have a numerically lower rate of asymptomatic intracranial hemorrhage [40.9% (9/22) vs. 50% (11/22), P = 0.545] and mortality [0 vs. 9.1% (2/22), P = 0.488] than in the AS group, although there were not statistically significant.

CONCLUSION

Among TO patients with etiology of large vessel atherosclerosis, no statistical differences in outcome are identified between balloon angioplasty alone versus acute stenting. Future randomized controlled trials are warranted.

Absent Cortical Venous Filling Is Associated with Aggravated Brain Edema in Acute Ischemic Stroke

BACKGROUND AND PURPOSE

Predicting malignant cerebral edema can help identify patients who may benefit from appropriate evidence-based interventions. We investigated whether absent cortical venous filling is associated with more pronounced early brain edema, which leads to malignant cerebral edema.

MATERIALS AND METHODS

Patients with acute ischemic stroke caused by large-vessel occlusion in the MCA territory who presented between July 2017 and September 2019 to our hospital were included. Collateral filling was rated using the modified Tan scale on CTA, and good collaterals were defined as a score of 2-3. The Cortical Vein Opacification Score (COVES) was calculated, and absent cortical venous filling was defined as a score of 0. Early brain edema was determined using net water uptake on baseline CT images. Malignant cerebral edema was defined as a midline shift of ≥5 mm on follow-up imaging or a massive cerebral swelling leading to decompressive hemicraniectomy or death. Multivariate linear and logistic regression models were performed to analyze data.

RESULTS

A total of 163 patients were included. Net water uptake was significantly higher in patients with absent than in those with favorable cortical venous filling (8.1% versus 4.2%; P < .001). In the multivariable regression analysis, absent cortical venous filling (β = 2.04; 95% CI, 0.75-3.32; P = .002) was significantly and independently associated with higher net water uptake. Absent cortical venous filling (OR, 14.68; 95% CI, 4.03-53.45; P < .001) and higher net water uptake (OR, 1.29; 95% CI, 1.05-1.58; P = .016) were significantly associated with increased likelihood of malignant cerebral edema.

CONCLUSIONS

Patients with absent cortical venous filling were associated with an increased early brain edema and a higher risk of malignant cerebral edema. These patients may be targeted for optimized adjuvant antiedematous treatment.