Collateral Circulation and Outcome in Atherosclerotic Versus Cardioembolic Cerebral Large Vessel Occlusion

Preoperative and intraoperative tirofiban during endovascular thrombectomy in large vessel occlusion stroke due to large artery atherosclerosis

BACKGROUND AND PURPOSE

The aim of this study is to investigate the efficacy and safety of preoperative versus intraoperative tirofiban in patients with large vessel occlusion (LVO) due to large artery atherosclerosis (LAA).

METHODS

This is a retrospective multicenter cohort study based on the RESCUE-RE (Registration Study for Critical Care of Acute Ischemic Stroke After Recanalization) trial enrolling patients with anterior circulation LVO classified as LAA within 24 h of onset. Patients were divided into three groups: preoperative tirofiban (PT), intraoperative tirofiban (IT), and no tirofiban (NT). Propensity score matching (PSM) was used to balance baseline characteristics. The efficacy outcomes included 90-day functional independence (modified Rankin Scale score = 0-2) and early partial recanalization (EPR; defined as a modified Thrombolysis in Cerebral Infarction score = 1-2a). The safety outcomes included symptomatic intracranial hemorrhage (sICH).

RESULTS

A total of 104 matched triplets were obtained through PSM. Compared with NT, PT increased 90-day functional independence (60.8% vs. 42.3%, p = 0.008) and EPR (42.7% vs. 18.3%, p < 0.001) rate, with a tendency to increase the asymptomatic intracranial hemorrhage (aICH) proportion (28.8% vs. 18.3%, p = 0.072). Compared with IT, PT had a higher 90-day functional independence (60.8% vs. 45.2%, p = 0.025) and EPR (42.7% vs. 20.2%, p = 0.001) rate, with no significant difference in sICH (14.4% vs. 7.7%, p = 0.122) and aICH (28.8% vs. 21.2%, p = 0.200). Compared with NT, IT had a lower 90-day mortality rate (9.6% vs. 24.0%, p = 0.005).

CONCLUSIONS

Tirofiban shows good adjuvant therapy potential in acute ischemic stroke-LVO due to LAA patients. PT is associated with higher rates of EPR and better therapeutic efficacy. In addition, EPR may be a potential way to improve prognosis.

Automated detection of large vessel occlusion using deep learning: a pivotal multicenter study and reader performance study

BACKGROUND

To evaluate the stand-alone efficacy and improvements in diagnostic accuracy of early-career physicians of the artificial intelligence (AI) software to detect large vessel occlusion (LVO) in CT angiography (CTA).

METHODS

This multicenter study included 595 ischemic stroke patients from January 2021 to September 2023. Standard references and LVO locations were determined by consensus among three experts. The efficacy of the AI software was benchmarked against standard references, and its impact on the diagnostic accuracy of four residents involved in stroke care was assessed. The area under the receiver operating characteristic curve (AUROC), sensitivity, and specificity of the software and readers with versus without AI assistance were calculated.

RESULTS

Among the 595 patients (mean age 68.5±13.4 years, 56% male), 275 (46.2%) had LVO. The median time interval from the last known well time to the CTA was 46.0 hours (IQR 11.8-64.4). For LVO detection, the software demonstrated a sensitivity of 0.858 (95% CI 0.811 to 0.897) and a specificity of 0.969 (95% CI 0.943 to 0.985). In subjects whose symptom onset to imaging was within 24 hours (n=195), the software exhibited an AUROC of 0.973 (95% CI 0.939 to 0.991), a sensitivity of 0.890 (95% CI 0.817 to 0.936), and a specificity of 0.965 (95% CI 0.902 to 0.991). Reading with AI assistance improved sensitivity by 4.0% (2.17 to 5.84%) and AUROC by 0.024 (0.015 to 0.033) (all P<0.001) compared with readings without AI assistance.

CONCLUSIONS

The AI software demonstrated a high detection rate for LVO. In addition, the software improved diagnostic accuracy of early-career physicians in detecting LVO, streamlining stroke workflow in the emergency room.

Impact of prior use of antiplatelet agents and non-vitamin K antagonist oral anticoagulants on stroke outcomes among endovascular-treated patients with high pre-stroke CHA2DS2-VASc score

BACKGROUND

We assessed the influence of prior non-vitamin K antagonist (NOAC) use on stroke outcomes after endovascular treatment (EVT) in patients at a high risk of stroke based on their pre-stroke CHA2DS2-VASc score, and compared them with those who did not use any antithrombotic (NAU) or antiplatelet (APT) agents.

METHODS

Data were collected from a multicenter database comprising consecutive acute ischemic stroke patients who underwent EVT during a span of 103 months. We evaluated pre-stroke CHA2DS2-VASc scores in enrolled patients and measured instances of successful reperfusion and symptomatic hemorrhagic transformation (SHT) following EVT as the main outcome measures.

RESULTS

Among 12 807 patients with acute ischemic stroke, 3765 (29.4%) had a history of atrial fibrillation. Of these, 418 patients with CHA2DS2-VASc scores ≥2 received EVT alone. The prior NOAC group showed higher successful reperfusion rates compared with the prior NAU and APT groups (p=0.04). Multivariate analysis revealed that prior NOAC use increased the likelihood of successful reperfusion after EVT (OR [95% CI] 2.54 [1.34 to 4.83], p=0.004) and improved stroke outcomes, while the prior APT group did not. Furthermore, the prior NOAC use group was not associated with SHT after EVT. Propensity score matching confirmed these findings.

CONCLUSION

Prior use of NOAC is associated with improved outcomes in high-risk stroke patients (pre-stroke CHA2DS2-VASc score ≥2) undergoing EVT.

Collateral assessment on magnetic resonance imaging/angiography up to 30 hours after stroke onset

PURPOSE

We aimed to validate hyperintense vessel sign (HVS) on FLAIR imaging or posterior cerebral artery (PCA) laterality on MR angiography beyond 4.5 hours after stroke onset.

MATERIALS AND METHODS

Data from acute ischemic stroke patients with internal carotid or middle cerebral artery occlusion who underwent CT perfusion imaging at baseline, follow-up MR perfusion imaging and angiography within 30 hours after stroke, without effective recanalization on follow-up imaging, were analysed retrospectively. Patients were separately classified as high or low HVS (>5 or ≤5 slices of HVS), and PCA laterality positive or negative group. We compared core and penumbra volumes at follow-up imaging and neurological outcomes between high or low HVS group, and between PCA laterality positive or negative group.

RESULTS

Of 49 patients analyzed, four patients with artifacts were excluded and 45 were classified into high (n = 23) or low (n = 22) HVS group. High group had a smaller core volume (median 32 ml versus 109 ml, p = 0.004), larger penumbra volume at follow-up (68 ml versus 0 ml, p = 0.001), and better outcomes (modified Rankin Scale at three months, 3 versus 5, p = 0.03). For PCA laterality analysis, 1 patient with previously occluded PCA was excluded and 48 patients were classified as positive (n = 22) or negative (n = 26). Positive group had larger core volume (116 ml versus 37 ml), and no significant differences in penumbral volumes or outcomes.

CONCLUSION

Prominent HVS in later time was associated with small core volume, persistent penumbra volume and favorable outcomes.

Thrombectomy improves functional independence in severe basilar artery occlusion with favorable collateral circulation

BACKGROUND AND PURPOSE

This study aimed to investigate the effect of collateral circulation on the outcomes of thrombectomy versus medical management alone in basilar artery occlusion (BAO) patients with varying stroke severities.

METHODS

Data from the ATTENTION cohort were used to perform a post-hoc analysis comparing the outcomes of thrombectomy with medical management in BAO patients with varying degrees of collateral circulation and stroke severity. Basilar Artery on Computed Tomography Angiography (BATMAN) scores were used to quantify the collateral circulation, and the effect was estimated through a primary outcome of 90-day functional independence (modified Rankin Scale score, mRS ≤2). Favorable versus unfavorable BATMAN scores were analyzed as both continuous and categorical variables, and an adjusted multivariate regression model was applied.

RESULTS

Among 221 BAO patients, thrombectomy significantly improved functional independence compared to medical management in patients with favorable BATMAN scores (aOR 7.75, 95% CI 2.78-26.1), but not in those with unfavorable BATMAN scores (aOR 1.33, 95% CI 0.28-6.92; pinteraction = 0.028). When treated as a continuous variable, increased BATMAN score was found to be associated with a higher likelihood of functional independence in the thrombectomy group (aOR 1.97, 95% CI 1.44-2.81; pinteraction = 0.053). In severe stroke patients with higher BATMAN scores (National Institutes of Health Stroke Scale (NIHSS) ≥21), we identified a significant interaction for treatment effect with thrombectomy compared to medical management (pinteraction = 0.042).

CONCLUSION

An increased BATMAN score was significantly associated with a higher probability of functional independence after thrombectomy than after medical management, particularly in patients with severe BAO.

Patchy profile sign in RAPID software: a specific marker for intracranial atherosclerotic stenosis in acute ischemic stroke

Purpose

Identifying the etiology of acute ischemic stroke (AIS) before endovascular treatment (EVT) is important but challenging. In CT perfusion imaging processed by perfusion software, we observed a phenomenon called patchy profile sign (PPS), that is, the hypoperfusion morphology in RAPID software is a discontinuous sheet pattern. This phenomenon is predominantly observed in patients diagnosed with intracranial atherosclerotic stenosis (ICAS). The study intends to assess whether the PPS can be used to differentiate ICAS from intracranial embolism.

Method

Patients with AIS due to M1 segment occlusion of the MCA who underwent mechanical thrombectomy were retrospectively enrolled. The receiver operating characteristic (ROC) curve analysis was performed to assess the value of PPS in predicting ICAS. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of the PPS for prediction of ICAS were calculated.

Results

A total of 51 patients were included in the study. The PPS was observed in 10 of 19 (52.6%) patients with ICAS, and in 2 of 32 (6.3%) patients with intracranial embolism (p < 0.001). Interobserver agreement for identifying PPS was excellent (κ = 0.944). The sensitivity, specificity, PPV, NPV, and accuracy of the PPS for predicting ICAS were 52.6, 93.8, 83.3, 76.9, and 78.4%, respectively.

Conclusion

The PPS on RAPID software is an imaging marker with high specificity for ICAS. Larger sample sizes are imperative to validate the findings.

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.

Baseline characteristics and outcome of stroke patients after endovascular therapy according to previous symptomatic vascular disease and sex

Aim

The aim of this study was to investigate baseline characteristics and outcome of patients after endovascular therapy (EVT) for acute large vessel occlusion (LVO) in relation to their history of symptomatic vascular disease and sex.

Methods

Consecutive EVT-eligible patients with LVO in the anterior circulation admitted to our stroke center between 04/2015 and 04/2020 were included in this observational cohort study. All patients were treated according to a standardized acute ischaemic stroke (AIS) protocol. Baseline characteristics and successful reperfusion, recurrent/progressive in-hospital ischaemic stroke, symptomatic in-hospital intracranial hemorrhage, death at discharge and at 3 months, and functional outcome at 3 months were analyzed according to previous symptomatic vascular disease and sex.

Results

995 patients with LVO in the anterior circulation (49.4% women, median age 76 years, median admission NIHSS score 14) were included. Patients with multiple vs. no previous vascular events showed higher mortality at discharge (20% vs. 9.3%, age/sex - adjustedOR = 1.43, p = 0.030) and less independency at 3 months (28.8% vs. 48.8%, age/sex - adjustedOR = 0.72, p = 0.020). All patients and men alone with one or multiple vs. patients and men with no previous vascular events showed more recurrent/progressive in-hospital ischaemic strokes (19.9% vs. 6.4% in all patients, age/sex - adjustedOR = 1.76, p = 0.028) (16.7% vs. 5.8% in men, age-adjustedOR = 2.20, p = 0.035). Men vs. women showed more in-hospital symptomatic intracranial hemorrhage among patients with one or multiple vs. no previous vascular events (23.7% vs. 6.6% in men and 15.4% vs. 5.5% in women, OR = 2.32, p = 0.035/age - adjustedOR = 2.36, p = 0.035).

Conclusions

Previous vascular events increased the risk of in-hospital complications and poorer outcome in the analyzed patients with EVT-eligible LVO-AIS. Our findings may support risk assessment in these stroke patients and could contribute to the design of future studies.

An Explainable Artificial Intelligence Model to Predict Malignant Cerebral Edema after Acute Anterior Circulating Large-Hemisphere Infarction

INTRODUCTION

Malignant cerebral edema (MCE) is a serious complication and the main cause of poor prognosis in patients with large-hemisphere infarction (LHI). Therefore, the rapid and accurate identification of potential patients with MCE is essential for timely therapy. This study utilized an artificial intelligence-based machine learning approach to establish an interpretable model for predicting MCE in patients with LHI.

METHODS

This study included 314 patients with LHI not undergoing recanalization therapy. The patients were divided into MCE and non-MCE groups, and the eXtreme Gradient Boosting (XGBoost) model was developed. A confusion matrix was used to measure the prediction performance of the XGBoost model. We also utilized the SHapley Additive exPlanations (SHAP) method to explain the XGBoost model. Decision curve and receiver operating characteristic curve analyses were performed to evaluate the net benefits of the model.

RESULTS

MCE was observed in 121 (38.5%) of the 314 patients with LHI. The model showed excellent predictive performance, with an area under the curve of 0.916. The SHAP method revealed the top 10 predictive variables of the MCE such as ASPECTS score, NIHSS score, CS score, APACHE II score, HbA1c, AF, NLR, PLT, GCS, and age based on their importance ranking.

CONCLUSION

An interpretable predictive model can increase transparency and help doctors accurately predict the occurrence of MCE in LHI patients not undergoing recanalization therapy within 48 h of onset, providing patients with better treatment strategies and enabling optimal resource allocation.

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.

Hemoglobin in large vessel occlusion: Look further than collaterals

BACKGROUND

Abnormal hemoglobin (Hb) levels lead to poorer outcomes in ischemic stroke, though the mechanisms remain elusive. We aimed to study the role of Hb on imaging and clinical outcomes, namely on collaterals as it is a known mediator of infarct growth.

METHODS

Retrospective cohort study of patients with large vessel occlusion ischemic stroke admitted to our center. Demographics, clinical and imaging variables were collected, particularly baseline hemoglobin, presence of anemia and collateral score. Collaterals were scored from 0 to 3 and defined as poor if 0-1. Multivariable analyses were performed for collateral score and clinical outcomes (3-month mortality and good prognosis).

RESULTS

We included 811 patients, 215 (26.5 %) with anemia. Patients with anemia were older, had more comorbidities and more severe strokes. Hemoglobin levels and anemia were not associated with collateral score (OR 0.97, 95 % CI 0.89-1.05, p = 0.414 and OR 0.89, 95 % CI 0.64-1.24, p = 0.487, respectively) nor with poor collaterals (OR 0.96, 95 % CI 0.88-1.05, p = 0.398 and OR 0.86, 95 % CI 0.60-1.23, p = 0.406, respectively). Hb levels were associated with 3-month mortality (OR 0.85, 95 % CI 0.76-0.96, p = 0.008).

CONCLUSION

Hemoglobin or anemia were not found to be associated with collateral status. Our results raise further questions regarding the pathophysiology of anemia and outcomes in ischemic stroke, highlighting the need for future research.

Benefit of endovascular treatment for primary versus secondary medium vessel occlusion: A multi-center experience

AIMS

This study aimed to compare the clinical outcomes and safety of endovascular treatment (EVT) in patients with primary versus secondary medium vessel occlusion (MeVO).

METHODS

From the endovascular treatment for acute ischemic stroke in the China registry, we collected consecutive patients with MeVO who received EVT. The primary endpoint was a good outcome, defined as a modified Rankin Scale (mRS) 0 to 2 at 90 days.

RESULTS

154 patients were enrolled in the final analysis, including 74 primary MeVO and 80 secondary MeVO. A good outcome at 90 days was achieved in 42 (56.8%) patients with primary MeVO and 33 (41.3%) patients with secondary MeVO. There was a higher probability of good outcomes in patients with the primary vs secondary MeVO (adjusted odds ratio, 2.16; 95% confidence interval, 1.04 to 4.46; p = 0.04). There were no significant differences in secondary and safety outcomes between MeVO groups. In the multivariable analysis, baseline ASPECTS (p = 0.001), final modified thrombolysis in cerebral infarction score (p = 0.01), and any ICH (p = 0.03) were significantly associated with good outcomes in primary MeVO patients, while baseline National Institutes of Health Stroke Scale (p = 0.002), groin puncture to recanalization time (p = 0.02), and early neurological improvement (p < 0.001) were factors associated with good outcome in secondary MeVO patients.

CONCLUSION

In MeVO patients who received EVT, there was a higher likelihood of poor outcomes in patients with secondary versus primary MeVO.

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.

Arterial transit artifact as a short-term prognostic indicator in acute ischemic stroke

BACKGROUND

Arterial transit artifact (ATA) observed on arterial spin labeling (ASL) was recently suggested to be associated with improved functional outcomes following acute ischemic stroke (AIS). AIS is a heterogeneous disease with diverse pathogenic mechanisms depending on the stroke subtype. This study aimed to investigate the association between ATA and 3-month functional outcomes in AIS patients according to etiology subtypes.

METHODS

Consecutive patients with AIS were included. All patients underwent ASL MRI with postlabeling delay (PLD) of 1.5 and 2.5 s. ATA was assessed from the ASL images of both PLDs. Stroke etiologic subtypes were determined according to the modified TOAST (Trial of ORG 10172 in Acute Stroke Treatment) classification. Short-term functional outcomes were evaluated using the 3-month modified Rankin scale (mRS). Log-binomial regression was applied to analyze the association between ATA and functional outcomes at 3 months after stroke.

RESULTS

Ninety-eight AIS patients (62.73 ± 13.05 years; 68 men) were finally included. ATA was detected in forty-six patients and most frequently seen in the large-artery atherosclerosis (LAA) subtype (35/46). The ATA group exhibited a lower percentage of patients with mRS > 2 compared to the group without ATA (36.5% vs. 19.6%; P < 0.001). ATA was independently associated with better 3-month clinical outcomes (adjusted risk ratio, 0.35[95% CI, 0.16-0.74]) in the multivariate log-binomial regression model. After stratification by TOAST subtypes, a significant association was found between ATA and better outcomes in the LAA subtype (adjusted risk ratio, 0.20[ 95% CI, 0.05-0.72]) but not in cardioembolism and small artery occlusion (SVO) subtype.

CONCLUSION

ATA is associated with better outcomes at 3 months in patients with AIS, especially in the LAA subtype, but this association attenuated in the cardioembolism and SVO subtypes.

Prognostic value of CBV index in patients with acute ischemic stroke treated with endovascular thrombectomy in late therapeutic window

Purpose

To evaluate the prognostic value of the cerebral blood volume (CBV) index for 90-day functional outcomes in patients with acute ischemic stroke (AIS) treated within a late therapeutic window.

Methods

We retrospectively reviewed patients who underwent pre-treatment computed tomography perfusion (CTP) and endovascular thrombectomy (EVT) for large-vessel occlusion (LVO) of the anterior circulation within the late therapeutic window between January 2021 and February 2023. Clinical data, the Alberta Stroke Program Early Computed Tomography Score (ASPECTS) based on unenhanced computed tomography (CT), and perfusion parameters, including ischemic core, hypoperfusion volume, mismatch volume between the core and penumbra, and CBV index, were assessed and compared between patients who achieved favorable outcomes (defined as a modified Rankin Scale score of 0-2).

Results

Of the 118 patients, 56 (47.5%) had favorable outcomes. In the univariate analysis, age, National Institutes of Health Stroke Scale (NIHSS) score at admission, ASPECTS score, CBV index, and ischemic core volume were significantly associated with functional outcomes (P < 0.05). In multivariate analyses, age (odds ratio [OR], 1.060; 95% confidence interval [CI] 1.013-1.110, P = 0.012), NIHSS score at admission (OR, 1.126; 95% CI 1.031-1.229, P = 0.009), and CBV index (OR, 0.001; 95% CI 0.000-0.240, P = 0.014) were independent predictors of a 90-day favorable outcome.

Conclusion

A high CBV index was independently associated with favorable outcomes in patients who underwent mechanical thrombectomy within the late therapeutic window. In addition, a higher CBV index reflects improved blood flow and favorable digital subtraction angiography collateral status.

White matter hyperintensity burden and collateral circulation in acute ischemic stroke with large artery occlusion

OBJECTIVE

This study aimed to investigate the association between white matter hyperintensity (WMH) burden and pial collaterals in acute strokes caused by intracranial large artery occlusion treated with mechanical thrombectomy in the anterior circulation, focusing on stroke subtypes.

METHODS

Consecutive patients undergoing mechanical thrombectomy between December 2019 and June 2022 were retrospectively screened. The Fazekas scale assessed WMH burden. Pial collaterals were categorized as either poor (0-2) or good (3-4) based on the Higashida score. A multivariable analysis was used to determine the relationship between WMH burden and pial collaterals. Subgroup analyses delved into associations stratified by stroke subtypes, namely cardioembolism (CE), tandem lesions (TLs), and intracranial atherosclerosis (ICAS).

RESULTS

Of the 573 patients included, 274 (47.8%) demonstrated poor pial collaterals. Multivariable regression indicated a strong association between extensive WMH burden (Fazekas score of 3-6) and poor collaterals [adjusted OR 3.04, 95% CI 1.70-5.46, P < 0.001]. Additional independent predictors of poor collaterals encompassed ICAS-related occlusion (aOR 0.26, 95% CI 0.09-0.76, P = 0.014), female sex (aOR 0.63, 95% CI 0.41-0.96, P = 0.031), and baseline Alberta Stroke Program Early Computed Tomography scores (aOR 0.80, 95% CI 0.74-0.88, P < 0.001). Notably, an interaction between extensive WMH burden and stroke subtypes was observed in predicting poor collaterals (P = 0.001), being pronounced for CE (adjusted OR 2.30, 95% CI 1.21-4.37) and TLs (adjusted OR 5.09, 95% CI 2.32-11.16), but was absent in ICAS (adjusted OR 1.24, 95% CI 0.65-2.36).

CONCLUSIONS

Among patients treated with mechanical thrombectomy for anterior circulation large artery occlusion, extensive WMH burden correlates with poor pial collaterals in embolic occlusion cases (CE and TLs), but not in ICAS-related occlusion.

Early neurological deterioration in patients with minor stroke due to isolated M2 occlusion undergoing medical management: a retrospective multicenter study

BACKGROUND

Patients with minor stroke and M2 occlusion undergoing best medical management (BMM) may face early neurological deterioration (END) that can lead to poor long-term outcome. In case of END, rescue mechanical thrombectomy (rMT) seems beneficial. Our study aimed to define factors relevant to clinical outcome in patients undergoing BMM with the possibility of rMT on END, and find predictors of END.

METHODS

Patients with M2 occlusion and a baseline National Institutes of Health Stroke Scale (NIHSS) score≤5 that received either BMM only or rMT on END after BMM were extracted from the databases of 16 comprehensive stroke centers. Clinical outcome measures were a 90-day modified Rankin Scale (mRS) score of 0-1 or 0-2, and occurrence of END.

RESULTS

Among 10 169 consecutive patients with large vessel occlusion admitted between 2016 and 2021, 208 patients were available for analysis. END was reported in 87 patients that were therefore all subjected to rMT. In a logistic regression model, END (OR 3.386, 95% CI 1.428 to 8.032), baseline NIHSS score (OR 1.362, 95% CI 1.004 to 1.848) and a pre-event mRS score=1 (OR 3.226, 95% CI 1.229 to 8.465) were associated with unfavorable outcome. In patients with END, successful rMT was associated with favorable outcome (OR 4.549, 95% CI 1.098 to 18.851). Among baseline clinical and neuroradiological features, presence of atrial fibrillation was a predictor of END (OR 3.547, 95% CI 1.014 to 12.406).

CONCLUSION

Patients with minor stroke due to M2 occlusion and atrial fibrillation should be closely monitored for possible worsening during BMM and, in this case, promptly considered for rMT.

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.

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.

From static to dynamic: live observation of the support system after ischemic stroke by two photon-excited fluorescence laser-scanning microscopy

Ischemic stroke is one of the most common causes of mortality and disability worldwide. However, treatment efficacy and the progress of research remain unsatisfactory. As the critical support system and essential components in neurovascular units, glial cells and blood vessels (including the blood-brain barrier) together maintain an optimal microenvironment for neuronal function. They provide nutrients, regulate neuronal excitability, and prevent harmful substances from entering brain tissue. The highly dynamic networks of this support system play an essential role in ischemic stroke through processes including brain homeostasis, supporting neuronal function, and reacting to injuries. However, most studies have focused on postmortem animals, which inevitably lack critical information about the dynamic changes that occur after ischemic stroke. Therefore, a high-precision technique for research in living animals is urgently needed. Two-photon fluorescence laser-scanning microscopy is a powerful imaging technique that can facilitate live imaging at high spatiotemporal resolutions. Two-photon fluorescence laser-scanning microscopy can provide images of the whole-cortex vascular 3D structure, information on multicellular component interactions, and provide images of structure and function in the cranial window. This technique shifts the existing research paradigm from static to dynamic, from flat to stereoscopic, and from single-cell function to multicellular intercommunication, thus providing direct and reliable evidence to identify the pathophysiological mechanisms following ischemic stroke in an intact brain. In this review, we discuss exciting findings from research on the support system after ischemic stroke using two-photon fluorescence laser-scanning microscopy, highlighting the importance of dynamic observations of cellular behavior and interactions in the networks of the brain's support systems. We show the excellent application prospects and advantages of two-photon fluorescence laser-scanning microscopy and predict future research developments and directions in the study of ischemic stroke.

Imaging features of cardioembolic stroke on 4-dimensional computed tomography angiography

Background

Identifying cardioembolic stroke is important for the decision-making of endovascular treatment and anticoagulation therapy. We aimed to explore the features of cardioembolic stroke on 4-dimensional (4D) computed tomography angiography (4D-CTA) and assess whether these features can assist in classifying stroke etiology.

Methods

In this retrospective study, we analyzed the images of 294 patients with acute ischemic stroke (AIS) from July 2020 to February 2022 at the First Affiliated Hospital of Chongqing Medical University, which had been consecutively collected. The data of 110 patients with occlusion of the M1/M2 segment of the middle cerebral artery (MCA) with/without intracranial internal carotid artery (ICA) occlusion were analyzed to calculate the clot burden score (CBS) and collateral score (CS), and the data of 88 patients with a clear origin and distal part were analyzed to measure clot length. Maximum intensity projection (MIP) and time MIP (tMIP) post-processing were used to assess the clot features. The Mann-Whitney U test was used to compare the clot characteristics between the 2 groups. Binary logistic regression was performed to assess the association between the image characteristics and cardioembolic stroke. Moreover, the receiver operating characteristic (ROC) curve was used to test the diagnostic efficacy of MIP/tMIP clot features in classifying cardioembolic stroke.

Results

Age, high-risk factors for cerebrovascular disease, high/medium-risk sources of cardioembolic stroke, clot length, CBS, and CS were significantly different between the cardioembolic stroke group and non-cardioembolic stroke group (P<0.05). In the cardioembolic stroke group, the median MIP and tMIP clot length was 12 mm [interquartile range (IQR), 8.3-17.4 mm] and 9.3 mm (IQR, 6.8-14.3 mm), respectively. In the non-cardioembolic stroke group, the median MIP and tMIP clot length was 6.5 mm (IQR, 4.7-11.5 mm) and 5.8 mm (IQR, 3.9-10.6 mm), respectively. Binary logistic regression showed that cardioembolic stroke was significantly associated with MIP-clot length [odds ratio (OR), 1.15; 95% confidence interval (CI): 1.02-1.29; P<0.05], tMIP-clot length (OR, 1.18; 95% CI: 1.02-1.36; P<0.05), and tMIP-CBS (OR, 3.96; 95% CI: 1.08-14.58; P<0.05). The area under the ROC curve (AUC) values of MIP clot length for identifying cardioembolic stroke were 0.75 (95% CI: 0.65-0.84, P<0.05), with a cut-off value of >7.4 mm [sensitivity: 84.62% (95% CI: 69.50-94.10%); specificity: 59.18% (95% CI: 44.20-73.00%)]. The AUC value of tMIP clot length was 0.72 (95% CI: 0.61-0.81, P<0.05), with a cut-off value of >5.4 mm [sensitivity: 92.31% (95% CI: 79.10-98.40%); specificity: 48.98% (95% CI: 34.40-63.70%)].

Conclusions

Clot length and CBS were overestimated on MIP images. Among the clot characteristics, clot length could identify cardioembolic stroke.

Atrial Fibrillation and Reperfusion Therapy in Acute Ischaemic Stroke Patients: Prevalence and Outcomes-A Comprehensive Systematic Review and Meta-Analysis

Atrial fibrillation (AF) significantly contributes to acute ischaemic stroke (AIS), yet its precise influence on clinical outcomes post-intravenous thrombolysis (IVT) and post-endovascular thrombectomy (EVT) has remained elusive. Furthermore, the overall prevalence of AF in AIS patients undergoing reperfusion therapy has not been clearly determined. Employing random-effects meta-analyses, this research aimed to estimate the pooled prevalence of AF among AIS patients undergoing reperfusion therapy, while also examining the association between AF and clinical outcomes such as functional outcomes, symptomatic intracerebral haemorrhage (sICH) and mortality. Studies comparing AF and non-AF patient groups undergoing reperfusion therapy were identified and included following an extensive database search. Forty-nine studies (n = 66,887) were included. Among IVT patients, the prevalence of AF was 31% (Effect Size [ES] 0.31 [95%CI 0.28-0.35], p < 0.01), while in EVT patients, it reached 42% (ES 0.42 [95%CI 0.38-0.46], p < 0.01), and in bridging therapy (BT) patients, it stood at 36% (ES 0.36 [95%CI 0.28-0.43], p < 0.01). AF was associated with significantly lower odds of favourable 90-day functional outcomes post IVT (Odds Ratio [OR] 0.512 [95%CI 0.376-0.696], p < 0.001), but not post EVT (OR 0.826 [95%CI 0.651-1.049], p = 0.117). Our comprehensive meta-analysis highlights the varying prevalence of AF among different reperfusion therapies and its differential impact on patient outcomes. The highest pooled prevalence of AF was observed in EVT patients, followed by BT and IVT patients. Interestingly, our analysis revealed that AF was significantly associated with poorer clinical outcomes following IVT. Such an association was not observed following EVT.

Rescue Intracranial Balloon Angioplasty with or without Stent Placement in Acute Strokes with Intracranial Atherosclerotic Disease

BACKGROUND

Optimal management of acute ischemic stroke (AIS) secondary to intracranial atherosclerotic disease (ICAD) refractory to conventional mechanical thrombectomy remains unclear. We aimed to investigate the clinical outcome of patients undergoing rescue intracranial balloon angioplasty with or without stent placement in the setting of AIS in our institution.

METHODS

This is a retrospective single-arm observational study to evaluate the efficacy and safety of rescue balloon angioplasty with or without stent placement in emergent large vessel occlusion (EVLO) strokes with underlying ICAD. We included all patients undergoing such rescue intervention within 24 hours of AIS presentation with EVLO between 2017 and 2021. We further evaluated stent or vessel reocclusion.

RESULTS

Of 20 patients undergoing rescue intervention, 3 cases achieved adequate recanalization of artery using balloon angioplasty alone. Seventeen patients required stent placement. Fourteen (70%) procedures resulted in National Institutes of Health Stroke Scale improvement in postprocedure and upon discharge. Among 6 (30%) procedures with worsening neurological measures, 3 had reoccluded stent 24-48 hours after procedure, 2 had symptomatic hemorrhagic conversion, and 1 had perforator occlusion. Nine patients (45%) had favorable functional outcome (modified Rankin Scale ≤2) at discharge, unchanged or improved at 3-month follow-up. The median modified Rankin Scale score was 4 (Interquartile range: 1.75-4) at discharge, improving to 3 (Interquartile range: 0-4) at 3-month follow-up. Two patients (10%) died during hospital stay.

CONCLUSIONS

Rescue angioplasty with or without stenting can lead to significant clinical improvement in patients with ICAD presenting with ELVO and refractory to thrombectomy; however, this procedure is associated with a high rate of morbidity in acute setting.

Tmax volume can predict clinical type in patients with acute ischemic stroke

OBJECTIVE

Endovascular therapy (EVT) is performed for acute ischemic stroke (AIS) with large vessel occlusion (LVO), however, the treatment strategies and clinical outcomes differ between cardiac embolism (CE) and intracranial arteriosclerosis-derived LVO (ICAS-LVO). We analyzed whether the time-to-max (Tmax) volume derived from perfusion imaging predicted clinical classification in AIS patients before EVT.

METHODS

Consecutive AIS patients with anterior circulation LVO evaluated by automated imaging software were retrospectively identified. Patients were classified into a CE group and an ICAS-LVO group, and parameters were compared between groups.

RESULTS

Thirty-nine patients were included and Tmax volume and Tmax > 6 s volume/Tmax > 4 s volume were significantly greater in the CE group than in the ICAS-LVO group (Tmax > 4 s volume: 261 mL vs. 149 mL, p = .01, Tmax > 6 s volume: 143 mL vs. 59 mL, p = .001, Tmax > 6 s volume/Tmax > 4 s volume: 0.59 vs. 0.40, p < .001). Multiple logistic regression analysis indicated an association between clinical classification and high Tmax > 6 s volume/Tmax > 4 s volume (p = .04).

CONCLUSION

The Tmax volume derived from perfusion imaging predicts the clinical classification of AIS patients before EVT.

The Pathophysiology of Collateral Circulation in Acute Ischemic Stroke

Cerebral collateral circulation is a network of blood vessels which stabilizes blood flow and maintains cerebral perfusion whenever the main arteries fail to provide an adequate blood supply, as happens in ischemic stroke. These arterial networks are able to divert blood flow to hypoperfused cerebral areas. The extent of the collateral circulation determines the volume of the salvageable tissue, the so-called "penumbra". Clinically, this is associated with greater efficacy of reperfusion therapies (thrombolysis and thrombectomy) in terms of better short- and long-term functional outcomes, lower incidence of hemorrhagic transformation and of malignant oedema, and smaller cerebral infarctions. Recent advancements in brain imaging techniques (CT and MRI) allow us to study these anastomotic networks in detail and increase the likelihood of making effective therapeutic choices. In this narrative review we will investigate the pathophysiology, the clinical aspects, and the possible diagnostic and therapeutic role of collateral circulation in acute ischemic stroke.

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.

Influence of the integrity of circle of Willis on asymptomatic or mild patients with first diagnosed chronic internal carotid artery occlusion

BACKGROUND

In order to identify individuals with chronic internal carotid artery occlusion (CICAO), it is essential to understand the integrity of the circle of Willis (CoW). This understanding is important as it may determine the potential benefits of active medical and endovascular treatments.

PURPOSE

The objective of this study is to assess whether diminished integrity of the CoW can serve as a useful marker for identifying individuals with more severe impairment in cerebral blood perfusion and a higher incidence of cerebral infarction among asymptomatic or mildly affected patients with CICAO.

MATERIALS AND METHODS

We conducted a retrospective review of asymptomatic or mildly affected patients with newly diagnosed CICAO who did not receive reperfusion therapies. The categorization of patients into good or poor integrity groups was based on the assessment of CoW integrity using CTA. We evaluated the volume and value of prolonged time to peak (TTP) in both groups, as well as the occurrence of new cerebral infarctions. Our analysis involved multivariate regression and receiver operating characteristic (ROC) analysis.

RESULTS

Hemodynamic abnormalities characterized by prolonged TTP were observed in the affected side's blood supply region in all 38 patients. There was a notable difference in the volume and value of prolonged TTP between the two groups (P < 0.001). Correlation analyses based on CTP and CTA parameters revealed a negative relationship between CoW scores and both the abnormal volume (r = -0.624, P = 0.000) and value (r = -0.589, P = 0.000) of prolonged TTP. Upon multivariable adjustment, the independent predictors for new cerebral infarction and higher volume of prolonged TTP were solely the CoW status, with respective estimates of (b = 6.05; 95% confidence interval [CI]: 1.619, 22.619; P = 0.007) and (b = 35.486; 95% CI: 4.697, 268.088; P = 0.001).

CONCLUSION

Assessing the integrity of the CoW is crucial in evaluating abnormal perfusion in asymptomatic or mildly affected individuals who are newly diagnosed with CICAO and have not undergone reperfusion therapy.

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.

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.

Early plasma D-dimer as a predictor of acute intracranial atherosclerosis-related large vessel occlusion in acute ischemic stroke

BACKGROUND

Intracranial atherosclerosis-related large vessel occlusion (ICAS+LVO) poses an important technical challenge for endovascular thrombectomy (EVT).

PURPOSE

To evaluate the value of D-dimer in predicting ICAS+LVO alone and in combination with other clinical and imaging predictors.

MATERIAL AND METHODS

Consecutive patients who underwent EVT at our center between January 2018 and June 2021 were retrospectively reviewed. Patients were classified to the ICAS+LVO or ICAS-LVO group according to angiographic findings. Collateral gradings were evaluated based on computed tomography angiography and categorized as follows: score 0-1 unfavorable collaterals and score 2-3 favorable collaterals. Receiver operating characteristic curve was analyzed to evaluate the predictive value of D-dimer and the combination of other predictors for ICAS+LVO.

RESULTS

A total of 374 patients were enrolled, among them, 107 (28.6%) had an ICAS+LVO, while ICAS-LVO was determined in 267 (71.4%) patients. Median D-dimer levels were lower (0.36 vs. 1.18 mg/L; P < 0.001) while the proportion of favorable collaterals was higher (85.0% vs. 22.5%; P < 0.001) in the ICAS+LVO group than the ICAS-LVO group. After multivariable analysis, D-dimer (adjusted odds ratio [OR]=0.32, 95% confidence interval [CI]=0.21-0.50; P < 0.001) and collaterals (adjusted OR=16.25, 95% CI=7.58-34.84; P < 0.001) remained independent predictors of ICAS+LVO. The area under the curve of D-dimer, collaterals, and combination for identification of ICAS+LVO was 0.82, 0.85, and 0.92, respectively.

CONCLUSION

Low early plasma D-dimer levels are a significant and independent predictor of ICAS+LVO, and predictive value strengthens when in a combined model using D-dimer and collateral grading.

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.

Predictors of Futile Recanalization in Patients with Intracranial Atherosclerosis-Related Stroke Undergoing Endovascular Treatment

OBJECTIVE

The predictors of futile recanalization in patients with intracranial atherosclerosis (ICAS)-related stroke are not understood. This study aimed to identify the predictors of futile recanalization after endovascular treatment (EVT) in patients who experience an acute stroke caused by ICAS-related occlusion.

METHODS

We retrospectively reviewed the data of patients with ICAS-related stroke who underwent EVT from January 2018 to July 2021. Futile recanalization was defined as functional dependence (modified Rankin scale 3-6) despite successful reperfusion (modified Thrombolysis in Cerebral Infarction score of 2 b/3). Multivariate logistic regression analysis was used to determine the risk factors associated with futile recanalization. The receiver operating characteristic curve was used to examine the predictive value of the risk prediction model for futile recanalization.

RESULTS

Of the 87 patients enrolled, futile recanalization was observed in 32 (36.8%). Multivariate logistic analysis showed that older age (OR, 1.05; 95% CI, 1.01-1.10; P = 0.026), a higher National Institutes of Health Stroke Scale (NIHSS) score on admission (OR, 1.25; 95% CI, 1.08-1.45; P = 0.003), and poor collaterals (OR, 5.49; 95% CI, 1.70-17.79; P = 0.004) were independently associated with futile recanalization after EVT in patients with ICAS-related stroke. The receiver operating characteristic curve showed that the model in combination with age, admission NIHSS score, and collateral status could accurately predict futile recanalization in these patients (areas under the curve, 0.85; 95% CI, 0.76-0.92; P < 0.001).

CONCLUSIONS

Older age, higher NIHSS score on admission, and poor collaterals are predictors of futile recanalization in patients with ICAS-related stroke.

Collateral Flow in Intracranial Atherosclerotic Disease

Intracranial atherosclerotic disease (ICAD) is a major cause of ischemic stroke and transient ischemic attack (TIA) worldwide. The culprit of ICAD is frequently a high-grade intracranial atherosclerotic stenosis (ICAS) pertaining to the infarct territory, and by then, the ICAS is described as symptomatic. A high-grade ICAS may progressively limit cerebral perfusion downstream, demanding collateral compensation. Collateral circulation refers to the pre-existing and dynamic emergence of vascular channels that maintain and compensate for a failing principal vascular route. Collaterals through the Circle of Willis and leptomeningeal circulation are of utmost importance in this regard. In this article, we first discussed the epidemiology, stroke mechanisms, contemporary therapeutics, and prognosis of symptomatic ICAD. Then, we reviewed the collateral routes in ICAS, factors associated with recruitment and development of the collaterals and diagnostic imaging modalities in assessing the origin and function of collateral circulation. We discussed the associations between collateral circulation and clinical outcomes after acute reperfusion treatment in ICAD-related ischemic strokes with or without large vessel occlusion (LVO). We also conducted a systematic review and meta-analysis on the associations of collateral circulation with the risk of recurrent stroke and the functional outcome in symptomatic ICAS patients on medical treatment as secondary stroke prevention. Finally, we summarized current evidence in these aspects and proposed the future directions.

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.

Outcomes in acute ischemic stroke patients undergoing endovascular thrombectomy: Cervical internal carotid artery pseudo-occlusion vs. true occlusion

Background and purpose

Pseudo-occlusion of the cervical internal carotid artery (cICA) refers to an absence of intraluminal contrast on computed tomography angiography (CTA), while the artery is patent on digital subtraction angiography during endovascular thrombectomy. We aimed to compare the outcomes between the cICA pseudo-occlusion and true occlusion after thrombectomy.

Methods

We retrospectively analyzed patients with apparent cICA occlusion on CTA who underwent thrombectomy between January 2016 and August 2021, and divided them into the pseudo-occlusion and true occlusion groups based on angiographic exploration. Recanalization failure was defined as a modified Thrombolysis in Cerebral Infarction score of 0-2a. Poor outcome was defined as a 90-day modified Rankin Scale score of 3-6. Propensity score matching was performed to compare the outcomes. Sensitivity analysis using multivariate-adjusted regression in the original cohort was conducted to test the robustness of the findings.

Results

Of the 146 patients included, 79 patients (54.1%) had cICA pseudo-occlusion and 67 patients (45.9%) had true occlusion. Following 1:1 propensity score-matched analysis, patients with pseudo-occlusion had an increased likelihood of recanalization failure (OR, 3.18; 95% CI, 1.06-9.59; P = 0.040) and poor outcome (OR, 2.80; 95% CI, 1.07-7.30; P = 0.035) compared with patients with true occlusion. Sensitivity analysis showed that cICA pseudo-occlusion remained independently associated with recanalization failure (OR, 2.55; 95% CI, 1.07-6.09; P = 0.036) and poor outcome (OR, 2.48; 95% CI, 1.08-5.67; P = 0.032).

Conclusions

Patients with cICA pseudo-occlusion on CTA treated with thrombectomy had an increased risk of reperfusion failure and poor outcome compared with true occlusion patients.

Outcome after endovascular treatment for acute ischemic stroke by underlying etiology: Tertiary experience and meta-analysis

Objective

To investigate the effect of two major etiologies [intracranial atherosclerotic stenosis (ICAS) and cardioembolism (CE])] on outcomes of acute ischemic stroke (AIS) patients due to large vessel occlusion (LVO) after endovascular thrombectomy (EVT).

Methods

Anterior circulation AIS patients receiving EVT were retrospectively analyzed. Clinical and laboratory data were collected. Clinical outcomes including favorable outcome (90-day modified Rankin Scale 0-2), mortality, intracranial hemorrhage (ICH) and symptomatic ICH (sICH) were compared. A systematic review and meta-analysis was also performed.

Results

A total of 302 AIS patients were included and divided into the ICAS group (86 patients) and the CE group (216 patients). Patients in the ICAS group were younger (62[18.0] vs. 68[19.0] years, p < 0.001), more likely to have smoking (52.3% vs. 26.9%, p < 0.001) and drinking (52.3% vs. 23.1%, p < 0.001) history, and more frequently required rescue therapy (80.2% vs. 4.6%, p < 0.001) compared to the CE group. However, favorable outcome (aOR 0.722, 95%CI 0.372-1.402, p = 0.336) and mortality (aOR 1.522, 95%CI 0.606-3.831, p = 0.371) were not significantly different between the two groups before and after adjustment. The incidence of sICH and ICH were comparable between the two groups before and after adjustment. Systematic review and meta-analysis consisted of 8 eligible studies (7 previous studies and this current study), incorporating 552 ICAS patients and 1,402 CE patients. Favorable outcome was slightly more likely in the ICAS group compared to the CE group (54.2% vs. 46.3%, OR 1.40, 95%CI 1.00-1.96, I ² = 53.2%). Moreover, the ICAS group had a lower rate of mortality (14.3% vs. 22.2%, OR 0.63, 95%CI 0.46-0.87, I ² = 0.0%) and ICH (19.5% vs. 31.9%, OR 0.60, 95%CI 0.42-0.84, I ² = 0.0%) than the CE group, while the two groups were similar in sICH rate (5.9% vs. 6.7%, OR 0.94, 95%CI 0.55-1.60, I ² = 6.3%).

Conclusion

Etiology was not considered as an important factor in functional outcome, despite the differences in baseline characteristics and technical EVT approach. The current study of anterior circulation AIS-LVO patients supports that outcomes for those with ICAS are not significantly different from those with CE.

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.

Impact of Anticoagulants in Reducing Mortality and Disability in Cardioembolic Stroke Patients

Background and Objectives: Stroke is currently the second most common cause of death and disability-adjusted life years worldwide. Previous studies have determined that cardioembolic stroke is associated with higher mortality. Our aim is to compare the long-term outcome and mortality of atherothrombotic, cardioembolic stroke patients and patients taking direct oral anticoagulants (DOACs), and to demonstrate that adequate treatment with DOACs is associated with better results. Materials and Methods: In our retrospective study, we collected the data of ischemic stroke patients who were treated at P. Stradins Clinical University Hospital, Riga, Latvia, Stroke Unit, in the year 2017. In the present study, we analyzed this information to assess the patients’ demographic and clinical data, vascular risk factors, functional and neurological evaluation results, and the use of anticoagulant therapy. Stroke survivors were followed-up via telephone at 30/90/180/365 days and 4 years after being discharged from the hospital. The Latvian version of the National Institutes of Health Stroke Scale (NIHSS-LV) was used to evaluate patients’ neurological outcomes at discharge, and patients’ functional outcomes were evaluated using the modified Rankin scale (mRS). The collected data of the patients were separated into three groups according to the stroke subtype and use of direct oral anticoagulants. Results: A total of 654 ischemic stroke patients were admitted to the hospital in the year 2017. Of all the strokes included in the study, 262 presented an atherothrombotic etiology and 392 presented a cardioembolic etiology. The median age of the patients in the study was 76 years (IQR: 67–83). The median age of patients in the atherothrombotic stroke group was 71 years (IQR = 64–79), in the cardioembolic stroke group it was 79 (IQR = 72–84), and in the DOAC group it was 75 years (IQR = 69–82), respectively. At the period of four years, of all the atherothrombotic stroke survivors 14 (10.5%) had a severe disability, and 64 (48.1%) did not survive. However, 12 (4.1%) of the cardioembolic stroke survivors were severely disabled and 37 (12.5%) had died. In the group of patients taking DOACs 6 (4.5%) had a severe disability and 17 (12.9%) did not survive. In all the patient groups, the leading cause of death was due to severe disability (22%), followed by recurrent cardioembolic events (8%). Conclusions: Previous studies until now have concluded that cardioembolic stroke is associated with higher mortality and an unfavorable functional outcome. In our study, the cardioembolic stroke group and the DOAC group had a statistically significant higher percentage of patients with congestive heart failure and older age, but their long-term mortality was lower and they achieved independence more often than the atherothrombotic stroke patients. The proper use of anticoagulants shows great improvement in long-term survival rate and functional outcome.

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.

Factors associated with favorable outcomes in acute severe stroke patients: A real‑world, national database study

Thrombolytic therapy is useful in severe stroke, but it increases the risk of intracerebral hemorrhage. In addition, it may have limited use in resource-limited due to a lack of trained neurologists and equipment to perform CT scans. There are limited data available from studies of national databases on stroke outcomes and predictors of severe stroke. This study, therefore, aimed to evaluate acute severe ischemic stroke outcomes in a real-world setting. Additionally, predictors of favorable stroke outcomes were explored using a retrospective cohort. Data were extracted from the National Health Security Office (NHSO) in Thailand. The inclusion criteria were: Aged ≥18 years or older, diagnosis of acute severe ischemic stroke (defined by an admission National Institutes of Health Stroke Scale score of 15-24), and available data on stroke outcomes. Outcomes were evaluated at discharge using a modified Rankin score at discharge. Factors associated with good outcomes were determined using multivariate logistic regression analysis. During the study period, 268 severe stroke patients met the inclusion criteria. Of those, 38 (14.18%) had good outcomes at discharge. A total of 223 patients received intravenous recombinant tissue plasminogen activator (83.21%). Of those, 38 (17.04%) had favorable outcomes. A predictive model for good outcomes revealed two independent factors: Male sex and atrial fibrillation with adjusted odds ratios (95% confidence interval) of 2.30 (1.10-4.82) and 0.38 (0.16-0.91), respectively. Predictors for good stroke outcomes in severe stroke patients included rtPA treatment, atrial fibrillation, and male sex.

Low-dose statins improve prognosis of patients with ischaemic stroke undergoing intra-arterial thrombectomy: A prospective cohort study

BACKGROUND

High-dose statins are recommended as preventive drugs in guidelines for patients with ischaemic stroke undergoing thrombectomy. Not only in clinical practice but also based on large-scale studies, low-dose statins have been widely used and demonstrated to be efficient in Asian populations. However, it remains unknown whether a low-dose statin is related to the prognosis of patients with thrombectomy. Can low-dose statins reduce the risk of bleeding at the same time?

METHODS

We prospectively collected data from patients with acute ischaemic stroke undergoing intra-arterial thrombectomy. Efficacy outcomes were National Institutes of Health Stroke Scale (NIHSS) score improvement at 7 days after admission and a favourable functional outcome (FFO) at 90 days. Safety outcomes were rates of in-hospital haemorrhage events and death within 2 years.

RESULTS

We included 256 patients in this study. Compared with the control group, the low-dose statin group had a higher NIHSS improvement rate at 7 days, a higher FFO rate at 90 days and a lower death rate within 2 years. The low-dose statin group had a lower percentage of gastrointestinal haemorrhage. Statin use was significantly related to an improved NIHSS score (p = 0.028, OR = 1.773) at 7 days and FFO (P < 0.001, OR = 2.962) at 90 days and to lower death rates (P = 0.025, or = 0.554) within 2 years.

CONCLUSION

In Asian acute ischaemic stroke patients with intra-arterial thrombectomy, low-dose statin use was significantly related to NIHSS improvement at 7 days, FFO at 90 days and decreased death rates within 2 years.

Intra-Arterial Thrombolysis Vs. Mechanical Thrombectomy in Acute Minor Ischemic Stroke Due to Large Vessel Occlusion

Background

The efficacy and safety of mechanical thrombectomy (MT) in acute large vessel occlusion (LVO) patients with minor stroke (NIHSS ≤ 5) remains undetermined. We aimed to compare the efficacy and safety of intra-arterial thrombolysis (IAT) alone vs. MT for LVO patients with minor stroke.

Methods

Patients were selected from the Acute Ischemic Stroke Cooperation Group of Endovascular Treatment (ANGEL) registry, a prospective multicenter registry study, and divided into MT and IAT alone groups. We compared the outcome measures between the two groups, including 90-day functional outcome evaluated by the modified Rankin Scale (mRS), the final recanalization level, intracranial hemorrhage, and mortality within 90-days by logistic regression models with adjustment. Besides the conventional multivariable analysis, we performed a sensitivity analysis by adjusting the propensity score to confirm our results. The propensity score was derived using a logistic regression model.

Results

Of the 120 patients, 63 received IAT alone and 57 received MT as the first-line treatment strategy. As compared to MT group, patients in the IAT alone group were associated with a higher chance of 90-day mRS 0-2 [93.7% vs. 71.9%, odds ratio (OR) = 4.75, 95% confidence interval (CI): 1.20–18.80, P = 0.027], a high chance of 90-day mRS 0-3 (96.8% vs. 86.7%, OR = 11.35, 95% CI: 1.93–66.86, P = 0.007), a shorter median time from puncture to recanalization (PTR) (60 min vs. 100 min, β = −63.70, 95% CI: −81.79– −45.61, P < 0.001), a lower chance of any intracranial hemorrhage (ICH) within 48 h (3.2% vs. 19.3%, OR = 0.15, 95% CI: 0.03–0.79, P = 0.025), and a lower chance of mortablity within 90 days (1.6% vs. 9.2%, OR = 0.05, 95% CI: 0.01–0.57, P = 0.016). Similarly, the sensitivity analysis showed the robustness of the primary analysis.

Conclusions

Compared with MT, IAT may improve 90-day clinical outcomes with decreased ICH rate and mortality in LVO patients with minor stroke.

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.

Quantitative Collateral Assessment on CTP in the Prediction of Stroke Etiology

BACKGROUND AND PURPOSE

Patients with stroke etiology of large-artery atherosclerosis were thought to have better collateral circulation compared with patients with other stroke etiologies. We aimed to investigate the association between stroke etiology and collateral circulation with a new quantitative collateral assessment method.

MATERIALS AND METHODS

This retrospective study reviewed data from consecutive patients with proximal anterior artery occlusion who underwent CTP before reperfusion therapy. CBF maps were derived from CTP. A new indicator, maximum CBF of collateral vessels within the Sylvian fissure (cCBF_max), was applied to quantitatively assess the collateral status. The relationship between collateral status and stroke etiology was investigated.

RESULTS

A total of 296 patients were finally analyzed. The median cCBF_max was significantly higher in patients with large-artery atherosclerosis than in those without it (92 [interquartile range, 65-123] mL/100 g/min versus 62 [interquartile range, 46-82] mL/100 g/min; P < .001). Multivariable analysis revealed that a higher cCBF_max score was independently associated with large-artery atherosclerosis etiology (OR, 1.010; 95% CI, 1.002-1.018; P = .017) after adjustment. The area under the curve, sensitivity, and specificity of the final model in predicting the etiology of large-artery atherosclerosis were 0.870, 89.7%, and 75.2%, respectively.

CONCLUSIONS

Patients with large-artery atherosclerosis had a more adequate collateral perfusion supply with the new quantitative collateral assessment. The new quantitative collateral measurement might contribute to the prediction of stroke etiology in the acute clinical scenario for patients with acute ischemic stroke.