Endovascular Therapy for Acute Stroke with a Large Ischemic Region

Intermittent theta burst stimulation regulates microglial polarization through Cry1 to enhance neuroplasticity for stroke recovery

BACKGROUND

Neuroplasticity is crucial for functional recovery after stroke, with modulation of microglial polarization enhancing this process. Intermittent theta burst stimulation (iTBS), as a neuromodulation technique, can simultaneously generate electric and magnetic fields to act on the central nervous system. Neurons can induce electrochemical signal transduction as excitable cells. Meanwhile, iTBS can regulate microglial inflammatory polarization post-stroke. However, how iTBS exerts its effect on microglia remains unclear. The magnetoreceptive protein Cryptochrome (Cry) can respond to the magnetic effect and is known to regulate macrophage-mediated inflammatory responses. However, whether iTBS modulates microglial polarization through Cry1 is unknown.

OBJECTIVE

To explore the magnetic effects of iTBS on microglial polarization through Cry1, thereby enhancing neuroplasticity and stroke recovery, and also elucidate the role of the Cry1-NF-κB pathway in iTBS-mediated regulation of microglial polarization.

METHODS

A mouse model was established using photothrombosis (PT), followed by 7-day iTBS intervention. BV2 cells and primary neurons were subjected to oxygen-glucose deprivation/reperfusion (OGD/R) respectively, followed by once-daily iTBS treatment for two days. Brain damage and functional recovery were assessed using Map-2 staining and behavioral tests. RT-PCR, western blot, immunofluorescence and transwell co-culture experiments were employed to evaluate the effects of iTBS on microglial polarization and neuroplasticity. Cry1 knockdown via siRNA transfection was used to explore the Cry1-NF-κB signaling pathway.

RESULTS

iTBS ameliorated neuronal damage induced by ischemic injury, reduced pro-inflammatory microglial activation, and promoted anti-inflammatory polarization. Cry1 expression was upregulated in BV2 cells in response to iTBS, while Cry1 knockdown increased CD16 expression, decreased CD206 expression and further alleviate the inhibition of NF-κB activation. In primary neurons, anti-inflammatory microglia induced by iTBS could enhance neuroplasticity.

CONCLUSION

This study demonstrates that post-stroke iTBS promotes neuroplasticity and functional recovery by regulating microglial polarization via the Cry1-NF-κB pathway.

Brain-targeting biomimetic nanozyme enhances neuroprotection in ischemic stroke by remodeling the neurovascular unit

Dysfunction of the neurovascular unit significantly impacts the prognostic outcomes of ischemic stroke. However, effective strategies to comprehensively modulate the neurovascular unit have yet to be developed. In this work, we introduce a brain-targeting biomimetic nanozyme, A@HPB@THSA, designed to mitigate neurovascular unit dysfunction following ischemia/reperfusion. Specifically, aspirin is encapsulated within a hollow Prussian blue nanozyme, which is subsequently modified with brain-targeting T7 peptide-conjugated human serum albumin, ultimately forming the composite A@HPB@THSA. The overexpression of transferrin receptors on cerebral vascular endothelial cells, along with compromised blood-brain barrier (BBB) permeability, facilitates the accumulation of A@HPB@THSA at cerebral ischemic lesions. The hollow Prussian blue nanozyme component effectively scavenges reactive oxygen species in ischemia/reperfusion-affected brain cells, while the aspirin component inhibits platelet aggregation and neutrophil infiltration, thereby preventing microvascular "no-reflow" and preserving the integrity of the BBB. In rat models of transient middle cerebral artery occlusion, A@HPB@THSA demonstrated comprehensive modulation of the neurovascular unit, including reduced BBB permeability, promoted microglia polarization toward an anti-inflammatory phenotype, and enhanced neuronal survival. This work provides a promising platform to reverse dysfunctional neurovascular unit for ischemic stroke treatment.

Endovascular Thrombectomy for Large Ischemic Core Stroke: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND AND OBJECTIVES

The optimal management of acute ischemic stroke (AIS) patients with large vessel occlusion and large ischemic core is uncertain. We aimed to evaluate the safety and efficacy of endovascular thrombectomy (EVT) compared with best medical treatment (BMT) for AIS through a study-level meta-analysis and meta-regression of 6 randomized controlled trials (RCTs).

METHODS

PubMed, Embase, and the Cochrane databases were searched from January 1, 1980, to June 30, 2024. We limited search results to RCTs which compared EVT vs BMT among large-core AIS. The Preferred Reporting Items for Systematic Reviews and Meta-analyses reporting guideline was used for abstracting and assessing data quality and validity. The risk ratio (RR) with 95% CI was used to measure the association of EVT vs BMT with outcomes. Univariable meta-regression analyses were conducted to evaluate possible moderating effects of onset to randomization time (OTR) on outcomes when comparing EVT with BMT. The primary outcome was the 90-day ordinal modified Rankin Scale (mRS). Secondary outcomes were independent ambulation (mRS 0-3) at 90 days, and symptomatic intracranial hemorrhage (sICH) and mortality at 90 days.

RESULTS

Six RCTs comprising 1,887 patients with large core AIS were included. Pooled results showed that EVT compared with BMT was associated with improved mRS score at 90 days (generalized OR, 1.6, 95% CI 1.4-1.8) and higher odds of independent ambulation (RR 1.9; 95% CI 1.5-2.5). Although the risk of sICH was higher in the EVT group (RR 1.7; 95% CI 1.1-2.7), there was a reduction in mortality in the EVT group (RR 0.9; 95% CI 0.8-1.0). Meta-regression showed that the benefit of EVT decreased with the extension of OTR (mRS 0-3, regression slope, -0.11, 95% CI -0.12 to -0.10; mRS 0-2, regression slope, -0.15, 95% CI -0.16 to -0.14). For patients with Alberta Stroke Program Early CT Score (ASPECTS) 0-2, EVT was associated with increased 90-day mRS 0-3 (RR 2.1, 95% CI 1.4-3.3) and mRS 0-2 (RR 2.8, 95% CI 1.2-6.7).

DISCUSSION

EVT improved clinical outcomes among patients with large-core AIS assessed by ASPECTS of 3-5 or volumetric methods. Patients with ASPECTS 0-2 also had benefit from EVT and require further study. These results support expansion of the routine application of EVT.

Sex-Related Differences in Endovascular Treatment Outcomes for Acute Large Infarcts: The ANGEL-ASPECT Subanalysis

BACKGROUND

The outcomes of endovascular therapy (EVT) across sexes for large infarcts remain unclear. This study aimed to evaluate the impact of sex on the outcomes of EVT or medical management for patients with large infarcts.

METHODS

In this secondary analysis of the ANGEL-ASPECT (Endovascular Therapy in Acute Anterior Circulation Large Vessel Occlusive Patients With a Large Infarct Core) randomized controlled trial conducted at 46 stroke centers across China between October 2, 2020, and May 18, 2022, we compared baseline characteristics and clinical outcomes between males and females, and each cohort further divided into EVT and medical management groups. The primary outcome was the 90-day modified Rankin Scale score distribution. Safety outcomes included symptomatic intracranial hemorrhage within 48 hours and mortality within 90 days.

RESULTS

There were 176 of 455 patients enrolled in the ANGEL-ASPECT trial who were female. There were 54.0% (95/176) of females and 48.4% (135/279) of males who underwent EVT. The treatment effect of EVT did not vary in both sexes with large infarcts (all P>0.05 for interaction). Compared with medical management, EVT improved 90-day functional outcomes for both males (3 [2-5] versus 4 [3-5]; common odds ratio, 1.94 [95% CI, 1.27-2.97]; P=0.002) and females (4 [3-6] versus 5 [4-6]; common odds ratio, 2.50 [95% CI, 1.41-4.45]; P=0.002). The symptomatic intracranial hemorrhage rate was not different in both treatment groups across both sexes (males, 5.2% versus 2.8%; odds ratio, 2.05 [95% CI, 0.56-7.50]; P=0.278; females, 7.4% versus 2.5%; odds ratio, 2.89 [95% CI, 0.55-15.14]; P=0.210).

CONCLUSIONS

In patients with large ischemic core, the treatment effect of EVT did not differ between females and males, with better outcomes with EVT versus medical management, without an increased risk of symptomatic intracranial hemorrhage. These findings emphasize the need for equal attention and care for both sexes with large infarcts in clinical practice.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT04551664.

Advances in treatments for acute ischemic stroke

Acute ischemic stroke is a leading global cause of death and disability. Intravenous thrombolysis was the first acute treatment developed for ischemic strokes. First with alteplase and now with tenecteplase, intravenous thrombolysis has remained a cornerstone of acute ischemic stroke management. In large vessel occlusions, endovascular thrombectomy has become the standard of care in acute stroke management for anterior and posterior circulation strokes. The boundaries for these treatments have expanded, which has improved outcomes in patients who were previously ineligible. This review summarizes the latest advances in interventions for acute ischemic stroke, extending beyond existing guidelines and review articles to explore emerging strategies and treatments currently under investigation.

Comparing Early National Institutes of Health Stroke Scale Versus 90-Day Modified Rankin Scale Outcomes in Acute Ischemic Stroke Trials: A Systematic Review and Analysis

BACKGROUND

Early National Institutes of Health Stroke Scale (NIHSS) assessment may provide practical benefits over 90-day modified Rankin Scale (mRS), but it is unclear how it compares in adjudicating randomized clinical trial (RCT) results in acute ischemic stroke.

METHODS AND RESULTS

We searched Ovid Medline (inception to April 1, 2023) and included RCTs of acute therapies for acute ischemic stroke with data for both 90-day mRS and NIHSS within 7 days. Primary outcome was agreement between trial results (classified as positive, negative, or neutral) based on 24-hour NIHSS and 90-day mRS scores. We additionally assessed agreement for 2-hour, 48-hour, 72- to 96-hour, and 5- to 7-day NIHSS scores. We aimed to validate our findings using individual patient data from the ESCAPE (Randomized Assessment of Rapid Endovascular Treatment of Ischemic Stroke) and ESCAPE-NA1 (Safety and Efficacy of Nerinetide [NA-1] in Subjects Undergoing Endovascular Thrombectomy for Stroke) RCTs. We included 116 trials (44 387 patients), contributing 165 NIHSS assessments. The 24-hour NIHSS scores resulted in the same classification as 90-day mRS scores in 61/73 (83.6%) trials (Cohen's kappa, 0.64 [95% CI: 0.45-0.83] and Gwet's agreement coefficient 1, 0.79 [95% CI: 0.67-0.90]). Agreement was not statistically different by timing of NIHSS assessments (range 75%-100%, P=0.33). Individual patient data showed higher agreement for assessments between 48 hours and 7 days, varying by NIHSS dichotomization cutoffs (NIHSS score, 0-2; 2 hours, 56.6%; 24 hours, 66.6%; 48 hours, 71.8%; 5-7 days: 76.5%, P<0.01; NIHSS score, 0-7; 2 hours, 72.8%; 24 hours, 80.5%; 48 hours, 83.1%; 5-7 days: 84.7%, P<0.01).

CONCLUSIONS

The 24-hour NIHSS scores aligned with 90-day mRS scores in 84% of RCT results, indicating intermediate-to-good agreement. However, individual patient data showed that early NIHSS risks misclassifying around 1/4 patients. These data contribute to a better understanding of the nuances of early NIHSS score as an outcome in acute ischemic stroke RCTs.

CT Perfusion Imaging After Selection for Late-Window Endovascular Stroke Treatment: Secondary Analysis of the MR CLEAN-LATE Randomized Trial

Importance

MR CLEAN-LATE (Multicenter Randomized Clinical Trial of Endovascular Treatment of Acute Ischemic Stroke in the Netherlands for Late Arrivals) showed efficacy of endovascular treatment (EVT) in the late window (6-24 hours after stroke symptom onset or time last seen well) among patients with ischemic stroke selected based on collateral flow. Therefore, the future role of computed tomography perfusion (CTP) imaging in patient selection for late-window EVT may change.

Objective

To investigate the interaction among CTP parameters (core volumes, penumbra volumes, and mismatch ratio) and the association of EVT with functional outcomes among patients in the late window after ischemic stroke selected based on collateral flow.

Design, Setting, and Participants

This is a post hoc secondary analysis of MR CLEAN-LATE, a multicenter randomized clinical trial, with open-label treatment and blinded end point, conducted from February 2, 2018, to January 27, 2022, in 18 Dutch stroke intervention centers. Participants included 502 patients with anterior circulation large vessel occlusion and present collateral flow on results of computed tomographic angiography in the late window after stroke, who gave deferred consent and were included in MR CLEAN-LATE. All patients had completed follow-up at 90 days. This secondary analysis included 313 patients (62%) with available CTP results. Statistical analysis was performed in September 2023.

Intervention

Patients were randomized to receive EVT (EVT group) and best medical management vs best medical management alone (no EVT group).

Main Outcomes and Measures

The primary outcome was functional outcome at 90 days measured by the modified Rankin Scale score. The treatment effect was analyzed in subgroups of core volumes, penumbra volume, and mismatch ratios using ordinal regression analysis. An interaction analysis was performed to assess whether CTP parameters modified the EVT effect on the modified Rankin Scale score at 90 days. All analyses were adjusted for relevant prognostic factors.

Results

Among the 313 patients (158 women [50%]) in the study, the median age was 73 years (IQR, 63-80 years), and the EVT group had fewer male participants than the no EVT group (73 of 168 [43%] vs 82 of 145 [57%]). Penumbra volumes significantly modified the association of EVT with outcomes (P < .001 for interaction), with the largest effect size among patients with penumbras of 120 mL or more (adjusted common odds ratio [ACOR], 6.89 [95% CI, 2.96-16.04]) and the smallest effect size among patients with penumbras of 72 mL or less (ACOR, 0.49 [95% CI, 0.22-1.08]). Core volume and mismatch ratio did not modify the EVT effect.

Conclusions and Relevance

Based on results from this secondary analysis of the MR CLEAN-LATE randomized clinical trial, there was a direct interaction between penumbra volume and treatment effect, and a trend toward potential harm of EVT was seen among patients with the smallest penumbras, which warrants further research. However, core volume and mismatch ratio did not seem to have additional value in patient selection.

Trial Registration

isrctn.org Identifier: ISRCTN19922220.

Thrombectomy Selection in the Large Core Era: Implications for Regional Transfers

PURPOSE OF REVIEW

This review aims to evaluate recent advances in large core stroke management with a focus on diagnostic imaging protocols to select patients for endovascular therapy.

RECENT FINDINGS

Recent randomized controlled trials have shown that thrombectomy can lead to favorable outcomes in patients with large infarcts, contradicting previous assumptions that thrombectomy was not indicated in such patients due to higher risks and very low benefits. Although mechanical thrombectomy remains the gold standard of medical treatment for large vessel occlusions with demonstrated salvageable brain tissue, analysis of the results of recent randomized trials in patients with large ischemic stroke should help us expand patient selection, optimize timing, and explore different management modalities to improve the outcomes of therapy in these patients.

Trends in revascularization therapies for patients with acute stroke with large infarcts: a population-based study

BACKGROUND

Evidence from randomized clinical trials shows that mechanical thrombectomy (MT) enhances functional outcomes in patients with large core ischemic stroke.

OBJECTIVE

To evaluate trends in the use of revascularization therapies, particularly MT, and their impact on functional outcomes in patients with large core ischemic stroke in routine clinical settings.

METHODS

Observational data from the Stroke Code Registry of Catalonia (CICAT, 2016-2024) were analyzed. Patients with anterior circulation ischemic stroke and Alberta Stroke Program Early CT Score (ASPECTS) <6, whether treated with reperfusion therapies or not, were included. Statistical analyses included trend analysis and multivariable logistic regression to identify predictors of favorable outcomes (modified Rankin Scale score 0-3 at 90 days) and mortality.

RESULTS

Among 599 patients, MT use increased significantly from 22% pre-2022 to 36% post-2022. This increase was associated with improved functional outcomes, with favorable outcomes rising from 29% to 43% post-2022. MT was a significant independent predictor of favorable outcomes (OR 3.4, 95% CI 2.1 to 5.5) and reduced mortality (OR 0.46, 95% CI 0.32 to 0.68). Intravenous thrombolysis also improved outcomes (OR 2.1, 95% CI 1.3 to 3.5). The benefit of MT was consistent across ASPECTS subgroups (0-2 and 3-5). Mediation analysis indicated that 88% of improvement could be attributed to increased MT use.

CONCLUSIONS

Increased MT use significantly improved outcomes for patients with large core ischemic stroke, particularly after 2022. Benefits were observed across subgroups, including those with very low ASPECTS. These findings support broadening MT access and suggest the need to update treatment guidelines to consider patients with large ischemic cores, aiming to optimize outcomes in routine clinical practice.

Blood pressure management based on infarct volume after successful endovascular thrombectomy

INTRODUCTION

While the efficacy of endovascular thrombectomy (EVT) in large core infarcts has been established, the influence of blood pressure (BP) management on functional outcomes based on infarct volume remains unclear.

PATIENTS AND METHODS

We conducted a secondary analysis of the Outcome in Patients Treated With Intra-Arterial Thrombectomy-Optimal Blood Pressure Control (OPTIMAL-BP) trial, which compared intensive (systolic BP < 140 mmHg) versus conventional (systolic BP 140-180 mmHg) BP management within the first 24 h following successful recanalization. Patients were grouped based on an infarct volume cut-off of 50 ml, assessed 24 h post-EVT. The primary efficacy outcome was functional independence (modified Rankin Scale of 0-2) at 3 months. Change of predicted probability for functional independence between BP managements, as infarct volume varied, was assessed.

RESULTS

Of the 300 patients, 222 (74.0%) were in the infarct volume ⩽50 ml group and 78 (26.0%) were in the infarct volume >50 ml group. The conventional management was significantly associated with a higher rate of functional independence in the infarct volume ⩽50 ml group (adjusted odds ratio [AOR], 2.06 [95% CI, 1.12-3.86]). In the infarct volume >50 ml group, the proportion of patients with functional independence was not significantly different between BP managements (AOR, 1.52 [95% CI, 0.46-5.04]). The interaction effect between the infarct volume groups and BP managements was not significant. As infarct volume increased, the difference in predicted probability of functional independence between BP managements decreased.

DISCUSSION AND CONCLUSIONS

Conventional BP management showed greater benefits for achieving functional independence at 3 months when infarct volumes were smaller. As infarct volume increased, the impact of BP management strategies on functional outcomes decreased.

REGISTRATION

ClinicalTrials.gov (NCT04205305).

Stroke Thrombectomy for Large Infarcts with Limited Penumbra: Systematic Review and Meta-Analysis of Randomized Trials

BACKGROUND

Recent randomized trials have suggested that endovascular thrombectomy (EVT) is superior to medical management (MM) for stroke patients with large infarcts. However, whether or how perfusion metrics should be used to guide optimal patient selection for treatment is unknown.

PURPOSE

To synthesize trial results to provide more definitive guidance on the role of EVT for stroke patients with large infarcts based on perfusion metrics.

DATA SOURCES

MEDLINE database from inception up to July 8, 2024. Randomized controlled trials that report the efficacy and safety of EVT for patients with large infarcts (defined by either infarct core volume greater than 50cc or Alberta Stroke Program Early CT Score [ASPECTS] less than 6) stratified by mismatch profile were included.

STUDY SELECTION

Five trials were identified - SELECT2 and ANGEL-ASPECT.

DATA ANALYSIS

The primary outcome was odds of acceptable outcomes (90-day modified Rankin scale [mRS] 0 to 3). Secondary outcome was 90-day mRS 5 or 6. Patients where then subdivided into those with mismatch ratio 1.2-1.8 or penumbra volume 10-15cc (intermediate mismatch) and those with mismatch ratio <1.2 or volume <10cc (low mismatch).

DATA SYNTHESIS

A total of 140 intermediate mismatch (75 EVT and 65 MM) and 60 low mismatch patients (23 EVT and 37 MM) were identified. EVT was significantly associated with higher odds of mRS 0-3 for intermediate mismatch (OR 2.77 [95% CI 1.11-6.89], P = .028), but not low mismatch (OR 1.47 [95% CI 0.44-4.94], P = .54). Similarly, in terms of 90-day poor outcomes (mRS 5-6), EVT for intermediate mismatch patients was significantly associated with lower odds (OR 0.49 [95% CI 0.24 to 0.99], P = .046), while EVT for the low mismatch cohort was not (OR 0.66 [95% CI 0.22 to 1.96], P = .45). There was no significant inter-study heterogeneity observed across study estimates.

CONCLUSIONS

For stroke patients with large infarcts, EVT was beneficial for patients with perfusion mismatch ratio and volume of at least 1.2 and 10cc, but not for those with mismatch ratio <1.2 or volume <10cc.

Addressing Heterogeneity in the Large-Core Trials: A Case for Standardized Imaging Analysis

Infarct detection is critically dependent on the imaging modality that is used and the criteria for defining tissue infarction. The recent trials of large-core thrombectomy used heterogeneous imaging methods to identify patients with large ischemic cores. Moreover, the Alberta Stroke Program Early CT Score methodology was not harmonized between the trials. Consequently, the large-core trial populations were distinct. To pool the populations in a clinically meaningful way, data should be pooled by imaging modality and time window. The imaging should be re-adjudicated using standardized criteria for imaging analysis and Alberta Stroke Program Early CT Score grading. This standardized approach can be disseminated into clinical practice so that the pooled treatment effect estimates can guide real-world patient care.

Thrombectomy With Low ASPECTS: The Roles of Infarct Volume and Postacute Neurological Status

BACKGROUND

Recent randomized trials demonstrated the beneficial effect of endovascular therapy in patients with low Alberta Stroke Program Early CT Score. Despite large follow-up infarct volumes, a significantly increased rate of good functional outcomes was observed, challenging the role of infarct volume as a predictive imaging marker. This analysis evaluates the extent to which the effects of endovascular thrombectomy on functional outcomes are explained by (1) follow-up infarct volume and (2) early neurological status in patients with stroke with low Alberta Stroke Program Early CT Score.

METHODS

TENSION (Efficacy and Safety of Thrombectomy in Stroke With Extended Lesion and Extended Time Window) was a randomized trial conducted from February 2018 to January 2023 across 41 stroke centers. Two hundred fifty-three patients with ischemic stroke due to anterior circulation large vessel occlusion and Alberta Stroke Program Early CT Score of 3 to 5 were randomized to endovascular thrombectomy plus medical treatment or medical treatment alone. All patients with the availability of relevant data points were included in this secondary as-treated analysis. The primary outcome was the 90-day modified Rankin Scale score. Confounder-adjusted mediation analysis was performed to quantify the proportion of the treatment effect on a 90-day modified Rankin Scale score explained by (1) 24-hour follow-up infarct volume and (2) 24-hour National Institutes of Health Stroke Scale scores.

RESULTS

One hundred eighty-eight patients were included; thereof, 87 (46%) were female patients. Median age was 72 (interquartile range, 63-79) years. The endovascular thrombectomy cohort had a 20.5 (95% CI, 8.3-33.7) percentage points higher probability of achieving independent ambulation (modified Rankin Scale, 0-3) and a 24.2 (95% CI, 13.4-35.8) percentage points lower mortality at 90 days compared with medical treatment alone. The reduction in 24-hour follow-up infarct volume explained 30% of the treatment effect on functional outcomes, while the 24-hour National Institutes of Health Stroke Scale score explained 61%.

CONCLUSIONS

In patients with low Alberta Stroke Program Early CT Score, infarct volume demonstrated limited explanatory power for functional outcomes compared with the early neurological status, which may more effectively reflect factors such as the involvement of specific brain regions, disruption of structural networks, and selective neuronal loss.

Differences in door-to-device times in a retrospective cohort of patients with ischemic stroke who received CTA only or CTA and CTP imaging

BACKGROUND

In the treatment of acute ischemic stroke, there are differing views about the utility of computerized tomography perfusion (CTP). Two approaches are employed depending on hospital preference. The first approach is to perform non-contrast computed tomography (CT) scans followed by vascular imaging with computed tomography angiography (CTA) for patients arriving within 6 h of last known well. In the first approach, CTP is reserved for patients who arrive 6-24 h after last known well. The second approach is to utilize both CTA and CTP regardless of the time window in which the patient presents. In this study, we sought to answer whether patients triaged with CTP and CTA had increased door-to-device times compared to those only triaged with CTA.

METHODS

We investigated a retrospective cohort of 1,357 patients with ischemic stroke who received endovascular therapy (EVT) and were triaged with CTA only or CTA and CTP. Patients were stratified by when they arrived at the hospital (<6 h and 6-24 h from last known well). Linear mixed-effects models (LMM) were used to investigate the association between door-to-device times and CTA/CTP usage.

RESULTS

Our results showed that using CTP and CTA was not associated with increased time to treat compared to CTA alone. There was no increase in time from door to device in patients presenting within 6 h. Furthermore, for patients who arrived 6-24 h of last known well, the use of CTP and CTA was associated with an accelerated time to treatment with EVT.

CONCLUSIONS

CTA and CTP usage was not associated with added time costs with respect to door-to-device in this patient cohort. Our results are consistent with other data showing that radiologists have faster read times when given both CTP and CTA. It is noteworthy that the majority of EVT patients in our dataset (70.6 %) presented in the <6-hour time window.

Anaesthesia modality on endovascular therapy outcomes in patients with large infarcts: a post hoc analysis of the ANGEL-ASPECT trial

OBJECTIVES

Endovascular therapy (EVT) now penetrates the once obscure realm of large infarct core volume acute ischaemic stroke (LICV-AIS). This research aimed to investigate the potential correlation between different anaesthetic approaches and post-EVT outcomes in LICV-AIS patients.

METHODS

Between October 2020 and May 2022, the China ANGEL-Alberta Stroke Programme Early CT Score (ASPECT) trial studied patients with LICV-AIS, randomly assigning them to the best medical management (BMM) or BMM with EVT. This post hoc subgroup analysis categorised subjects receiving BMM with EVT into general anaesthesia (GA) and non-GA groups based on anaesthesia type. We applied multivariable logistic regression to evaluate the relationship between anaesthesia during EVT and patient functional outcomes, as measured by the modified Rankin scale (mRS), in addition to the occurrence of complications. Further adjustment for selection bias was achieved through propensity score matching (PSM).

RESULTS

In total, 230 patients with LICV-AIS were enrolled (GA 84 vs Non-GA 146). No significant difference was observed between the two groups in terms of the proportion of patients who achieved an mRS score of 0-2 at 90 days (27.4% for the GA group vs 31.5% for the non-GA group, p=0.51). However, the GA group had significantly longer median surgical times (142 min vs 122 min, p=0.03). Furthermore, GA was associated with an increased risk of postoperative pneumonia (adjusted OR 2.03, 95% CI 1.04 to 3.98). The results of PSM analysis agreed with the results of the multivariate regression analysis. No significant difference in intracranial haemorrhage incidence or mortality rate was observed between the groups.

CONCLUSION

This post hoc analysis of subgroups of the ANGEL-ASPECT trial suggested that there may be no significant association between the choice of anaesthesia and neurological outcomes in LICV-AIS patients. However, compared with non-GA, GA prolongs the duration of EVT and is associated with a greater postoperative pneumonia risk.

TRIAL REGISTRATION NUMBER

NCT04551664.

Endovascular Thrombectomy for Ischemic Stroke With Large Infarct

Endovascular thrombectomy (EVT) is a safe and effective treatment for acute ischemic stroke caused by large vessel occlusion. However, earlier randomized trials of endovascular thrombectomy did not include many patients with large infarctions, leading to their exclusion from this treatment. Recent randomized trials have shown that endovascular thrombectomy is superior to medical management alone in improving functional outcomes in ischemic stroke cases with large infarcts. This commentary provides an overview of these trials and discusses important considerations for implementing these results into clinical practice.

Predictors of parenchymal hemorrhage after endovascular treatment in large core ischemic stroke: a post-hoc analysis of the ANGEL-ASPECT trial

BACKGROUND

The efficacy of mechanical thrombectomy (MT) for treating large infarcts has been established through multiple recent randomized controlled trials (RCTs). Nevertheless, hemorrhagic transformation (HT) remains one of the significant challenges following thrombectomy in these patients.

METHODS

This study presents a post-hoc analysis of the Study of Endovascular Therapy in Acute Anterior Circulation Large Vessel Occlusive Patients with a Large Infarct Core (ANGEL-ASPECT) trial. We included all patients with large infarcts who underwent thrombectomy and had imaging data available for HT assessment. Multivariate regression models were developed to determine the predictive factors for post-thrombectomy parenchymal hemorrhage (PH) and examine the relationship between PH and patient outcomes.

RESULTS

This study enrolled 217 patients, of whom 35 (16.1%) experienced PH 24-48 hours after thrombectomy. Multivariate analysis showed that patients with PH had a significantly worse functional outcome compared with patients without PH (modified Rankin Scale (mRS) score 5 vs 3, adjusted common OR (acOR) 0.31, 95% CI 0.16 to 0.61, P<0.01). Alcohol use (acOR 3.22, 95% CI 1.29 to 8.03, P=0.01) and an increased number of thrombectomy attempts (acOR 1.43, 95% CI 1.02 to 2.00, P=0.04) were independently associated with a heightened risk of PH. Conversely, local sedative anesthesia (acOR 0.10, 95% CI 0.01 to 0.84, P=0.03) was linked to a reduced risk of PH.

CONCLUSIONS

In patients with large infarcts, PH is associated with a poorer functional prognosis after thrombectomy. Alcohol use and a higher number of thrombectomy attempts were positively associated with the occurrence of PH, whereas local sedative anesthesia was negatively correlated with its occurrence.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Identifier: NCT04551664.

Accuracy and usefulness of dual-energy computed tomography after mechanical thrombectomy: A retrospective study

PURPOSE

Hemorrhagic complications are serious concern following mechanical thrombectomy (MT), making early identification crucial. Dual Energy Computed Tomography (DECT)is considered a potentially effective tool for postoperative evaluation, as it minimizes the effects of contrast leakage. This study examined the accuracy and usefulness of the results.

METHODS

We retrospectively identified 118 patients who had DECT immediately after MT at our institution between April 2020 and March 2024. Follow-up imaging with either CT or Magnetic Resonance Imaging was conducted the day after MT to evaluate consistency with the immediate postoperative DECT findings.

RESULTS

Of the 118 cases, 39 were suspected to have bleeding based on immediate postoperative DECT, and 37 of these were confirmed to have actual bleeding on imaging evaluation the day after MT. Two cases were false positive on DECT. On the other hand, there was one case that bleeding was not initially suspected on immediate postoperative DECT, but was later identified on subsequent imaging. The overall sensitivity and specificity of DECT were 97.4 % and 97.5 %, respectively.

CONCLUSIONS

Immediate postoperative DECT demonstrated high reliability, with excellent sensitivity and specificity. DECT may serve as an effective indicator for secondary prevention management and blood pressure control during the immediate postoperative period following MT.

Effect of intravenous alteplase before endovascular therapy for atherothrombotic stroke-related large vessel occlusion: subanalysis of the RESCUE AT-LVO registry

BACKGROUND

Whether intravenous thrombolysis (IVT) should be administered prior to endovascular therapy (EVT) in patients with atherothrombotic stroke-related large vessel occlusion (AT-LVO) remains unclear. This study aimed to assess the efficacy and safety of IVT administered before EVT in this patient population.

METHODS

We analysed the data from a multicentre registry of patients who underwent EVT for AT-LVO. Patients were categorised based on presumed mechanism of occlusion: in situ occlusion (intracranial group) or embolism from cervical artery occlusion/stenosis (tandem group). We compared the efficacy and safety of IVT before EVT in patients who received IVT (IVT stratum) and those who did not (non-IVT stratum). The primary outcome was a modified Rankin Scale score of 0-2 at 90 days.

RESULTS

Among the 336 patients in the intracranial group, 99 patients underwent IVT. The rate of favourable functional outcomes did not differ between IVT and non-IVT strata (51.1% vs 47.6%; adjusted ORs (aORs) (95% CI), 1.18 (0.66 to 2.09)); whereas any intracranial haemorrhage (ICH) (10.1% vs 3.8%; aOR, 2.98 (1.01 to 9.26)) and mortality at 90 days (6.4% vs 1.3%; aOR, 4.66 (1.02 to 26.73)) were significantly higher in the IVT stratum. Among the 233 patients in the tandem group, 88 patients underwent IVT, with no significant differences in efficacy or safety outcomes between the strata.

CONCLUSION

In patients with AT-LVO, IVT before EVT did not improve outcomes and was associated with increased risk of ICH and mortality in those with in situ intracranial occlusion. IVT before EVT may not be recommended in patients with atherosclerotic intracranial occlusions.

Novel Risk Score to Predict Poor Outcome After Endovascular Treatment in Anterior Circulation Occlusive Acute Ischemic Stroke

BACKGROUND

We aimed to develop and validate a prognostic score to predict outcomes after endovascular treatment in acute ischemic stroke.

METHODS

The prognostic score was developed based on the ACTUAL (Endovascular Treatment for Acute Anterior Circulation Ischemic Stroke) registry. The validation cohort was derived from the Captor trial. Independent predictors of poor outcome after endovascular treatment were obtained from the least absolute shrinkage and selection operator regression and multivariable logistic regression. Corresponding regression coefficients were used to generate point scoring system. The area under the receiver operating characteristic curve and the Hosmer-Lemeshow goodness-of-fit test were used to assess model discrimination and calibration. The predictive properties of the developed prognostic score were validated and the discriminative power was compared with other validated tools.

RESULTS

A 17-point Age, Collateral Status, Blood glucose, Alberta Stroke Program Early Computed Tomography Score, and National Institutes of Health Stroke Scale score scale was developed from the set of independent predictors, including age, admission National Institutes of Health Stroke Scale score, Alberta Stroke Program Early Computed Tomography Score on initial computed tomography scan, blood glucose, and collateral status. The scale showed good discrimination in the derivation cohort (area under the receiver operating characteristic curve, 0.79 [95% CI, 0.75-0.82]) and validation cohorts (area under the receiver operating characteristic curve, 0.77 [95% CI, 0.70-0.84]). The scale was well calibrated (Hosmer-Lemeshow test) in the derivation cohort (P=0.57) and validation cohort (P=0.75).

CONCLUSIONS

The Age, Collateral Status, Blood glucose, Alberta Stroke Program Early Computed Tomography score, and National Institutes of Health Stroke Scale score scale is a valid tool for predicting outcomes and may be useful for endovascular stroke treatment in anterior circulation large vessel occlusions.

Long-term functional outcomes for elderly patients treated with endovascular thrombectomy

BackgroundFunctional outcomes in elderly thrombectomy patients have been commonly reported up to 90 days, though long-term neurological status is not as well characterized. We studied 1-year outcomes in patients ≥ 80 years old and identified predictors of functional independence in elderly patients.MethodsRetrospective analysis of anterior circulation thrombectomy patients presenting from November 2016-August 2023 to a large health system. The primary outcome was 1-year modified Rankin Scale score (mRS) 0-2. Outcomes were compared between patients ≥ 80 and < 80 years old. Logistic regression was performed to identify predictors of 1-year functional independence in the elderly.Results957 patients were included, 220 (23%) of whom were ≥ 80 years old. A significantly lower proportion of patients ≥ 80 years old, compared to < 80 years, were functionally independent at 1-year (18.6% versus 45.9%, p < 0.001). In the elderly, predictors of functional independence included age (odds ratio (OR) 0.83, 95% confidence interval (CI) 0.74-0.93, p = 0.002), premorbid mRS score (OR 0.51, 95% CI 0.29-0.88, p = 0.016), presenting National Institutes of Health Stroke Scale score (OR 0.93, 95% CI 0.87-0.995, p = 0.035), cerebral blood volume index (OR 50.7, 95% CI 2.8-935, p = 0.008), and first-pass recanalization (OR 2.77, 95% CI 1.20-6.38, p = 0.017).ConclusionElderly thrombectomy patients had lower rates of functional independence at 1-year, though these are similar to previously reported rates at 90-days in octogenarians and nonagenarians. Factors associated with good outcomes in the elderly, including collateral status and single-pass revascularization, may be prognostically informative beyond the 90-day time window.

Advances in endovascular thrombectomy for the treatment of acute ischemic stroke

INTRODUCTION

Acute ischemic stroke (AIS) is the second leading cause of death and one of the leading causes of long-term disability globally. Endovascular thrombectomy (EVT) has revolutionized treatment for large vessel occlusion (LVO), providing 20% increase in post-stroke functional independence compared to intravenous thrombolysis (IVT) alone. Despite its proven efficacy, EVT is underutilized. While it is suitable for at least 15-20% of AIS patients, its mean adoption ranges from less than 1% to 7% in different areas.

AREAS COVERED

This review highlights key findings from pivotal randomized controlled trials and real-world data, focusing on patient selection criteria, advancements in thrombectomy devices, and procedural innovations. A comprehensive literature search was performed using PubMed, Scopus, EMBASE and the Cochrane Library for relevant randomized controlled trials and observational studies.

EXPERT OPINION

Disparity in access to EVT requires strategic investments in healthcare systems and international multidisciplinary collaboration. Enhancing geographic coverage with thrombectomy-capable centers and optimizing prehospital triage systems are essential. Bridging the gap between treatment capability and real-world implementation is critical to improving global AIS outcomes.

Thrombus iodine-based perviousness is associated with recanalisation and functional outcomes in endovascular thrombectomy

BACKGROUND

Dual-energy CT (DECT) provides several novel methods to assess thrombus perviousness. We aimed to evaluate whether the novel thrombus perviousness measured with DECT is associated with improved recanalisation and better functional outcomes in acute ischaemic stroke (AIS) patients with endovascular thrombectomy (EVT).

METHODS

108 AIS patients with middle cerebral artery occlusion who underwent DECT angiography on admission and received EVT treatment between April 2020 and September 2023 were retrospectively analysed. Thrombus attenuation increase (TAI) was evaluated on routine CT angiography and non-contrast CT, and DECT quantitative parameters of thrombus, including iodine concentration (IC) and normalised IC (NIC) were measured. Multivariable logistic regression analysis was used to evaluate the association of thrombus characteristics with arterial occlusive lesion scale and 90-day modified Rankin Scale.

RESULTS

NIC was significantly associated with successful recanalisation (OR 1.372 (95% CI 1.194 to 1.625); p<0.001) and good functional outcome (OR 1.252 (95% CI 1.114 to 1.446); p<0.001). NIC yielded higher performance, with area under curve (AUC) of 0.789 and 0.740, in the prediction of recanalisation and functional outcome than TAI (AUCs=0.635 and 0.592). Compared with low-level NIC thrombus, high-level NIC was associated with 11.4 and 15.4 times higher likelihood of successful recanalisation and good functional outcome. Moreover, NIC was a significant indicator to differentiate large artery atherosclerosis from cardioembolism stroke with high specificity and positive predictive value.

CONCLUSIONS

Higher DECT-derived NIC is associated with increased odds of successful recanalisation and good functional outcome for EVT patients, and it yielded higher prediction performance than TAI.

CT-Based Intrathrombus and Perithrombus Radiomics for Prediction of Prognosis after Endovascular Thrombectomy: A Retrospective Study across 2 Centers

BACKGROUND AND PURPOSE

Complications from endovascular thrombectomy (EVT) can negatively affect clinical outcomes, making the development of a more precise and objective prediction model essential. This research aimed to assess the effectiveness of radiomics features derived from presurgical CT scans in predicting the prognosis post-EVT in patients with acute ischemic stroke.

MATERIALS AND METHODS

This investigation included 336 patients with acute ischemic stroke from 2 medical centers from March 2018 to March 2024. The participants were split into a training cohort of 161 patients and a validation cohort of 175 patients. Patient outcomes were rated with the mRS: 0-2 for good, 3-6 for poor. A total of 428 radiomics features were derived from intrathrombus and perithrombus regions in noncontrast CT and CTA images. Feature selection was conducted using a least absolute shrinkage and selection operator regression model. The efficacy of 8 different supervised learning models was assessed using the area under the curve (AUC) of the receiver operating characteristic curve.

RESULTS

Among all models tested in the validation cohort, the logistic regression algorithm for the combined model achieved the highest AUC (0.87; 95% CI, 0.81-0.92), outperforming other algorithms. The combined use of radiomics features from both the intrathrombus and perithrombus regions significantly enhanced diagnostic accuracy over models using features from a single region (0.81 versus 0.70, 0.77), highlighting the benefit of integrating data from both regions for improved prediction.

CONCLUSIONS

The findings suggest that a combined radiomics model based on CT serves as a potent approach to assessing the prognosis following EVT. The logistic regression model, in particular, proved to be both effective and stable, offering critical insights for the management of stroke.

Impact of Intracranial Hemorrhage After Endovascular Treatment for Medium Vessel Occlusion

BACKGROUND AND OBJECTIVES

Endovascular treatment (EVT) for medium vessel occlusion (MeVO) raises concern about hemorrhagic complications; however, its clinical impact has not been elucidated. Therefore, we investigated the association between intracranial hemorrhage (ICH) after EVT for MeVO and functional outcomes.

METHODS

We conducted a post hoc analysis of the Japan Registry of NeuroEndovascular Therapy 4, a nationwide registry in Japan from 2015 to 2019 including 13 479 patients who underwent EVT for acute ischemic stroke. This study included 2465 patients with MeVO from 166 participating centers in Japan. We compared patients who underwent EVT for MeVO according to their hemorrhagic complication after EVT (no ICH, asymptomatic ICH, and symptomatic ICH). Outcomes included a modified Rankin scale (mRS) score at 30 days and all-cause mortality within 30 days. We estimated the odds ratios (ORs) and their CIs using a multivariable logistic regression model.

RESULTS

Among 2394 patients analyzed, 302 (12.6%) developed ICH, with 95 (31.5%) being symptomatic. Compared with the no-ICH group (n = 2092), the asymptomatic and symptomatic ICH groups had a lower proportion of patients with an mRS score of 0 to 2 at 30 days (41% vs 34%, vs 7.4%, P for trend <.001), with an adjusted ORs of 0.77 (95% CI, 0.53-1.12) and 0.12 (95% CI, 0.05-0.30) in the asymptomatic and symptomatic ICH groups, respectively. The adjusted common ORs of one-point shift of mRS score at 30 days in the asymptomatic ICH group was 0.76 (95% CI, 0.57-0.99) and that of the symptomatic ICH group was 0.13 (0.07-0.23), compared with the no-ICH group.

CONCLUSION

ICH after EVT for MeVO was associated with worse outcomes, whether they were symptomatic or not. The optimal treatment devices or techniques to reduce ICH after EVT for MeVO are crucial.

Clinical Severity and Outcomes in Large Infarcts With Endovascular Therapy: A Post Hoc Analysis of the ANGEL-ASPECT Trial

BACKGROUND

Endovascular therapy (EVT) has been proven effective for patients with acute ischemic stroke with large infarcts. This study aimed to explore the impact of clinical severity on the efficacy of EVT in such patients.

METHODS

This was a post hoc analysis of the ANGEL-ASPECT trial (Endovascular Therapy in Acute Anterior Circulation Large Vessel Occlusive Patients With a Large Infarct Core), a randomized controlled trial that enrolled patients from 46 centers across China between October 2, 2020, and May 18, 2022. These patients had large infarcts (defined as Alberta Stroke Program Early CT Score of 3-5 or infarct-core volume 70-100 mL) due to anterior-circulation large vessel occlusion within 24 hours after stroke onset with a National Institutes of Health Stroke Scale score of 6 to 30. Patients were randomized into either the EVT group or the medical management alone (MM) group. For this analysis, we categorized the patients into 2 subgroups: moderate stroke and severe stroke, based on a baseline National Institutes of Health Stroke Scale score of either <20 or ≥20. The primary outcome was the ordinal 90-day modified Rankin Scale score (0, no symptoms, to 6, death).

RESULTS

Among 455 eligible patients, 347 (76.3%) presented with moderate stroke (170 received EVT, 177 underwent MM), and 108 (23.7%) had severe stroke (60 received EVT, 48 underwent MM). A significant shift toward better outcomes in the 90-day modified Rankin Scale distribution was observed in the EVT group compared with the MM group (generalized odds ratio, 1.66 [95% CI, 1.29-2.13]; P<0.001) among patients with moderate stroke. However, this was not the case for those with severe stroke (generalized odds ratio, 1.06 [95% CI, 0.54-2.10]; P=0.87), indicating a significant interaction (P=0.03).

CONCLUSIONS

In patients with acute large infarcts, EVT was associated with improved functional outcomes compared with MM in patients with moderate stroke. However, no significant difference was observed in patients with severe stroke. Therefore, stroke severity should be considered when selecting patients with large infarcts for EVT.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT04551664.

Endovascular thrombectomy in acute stroke with a large ischemic core: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Endovascular thrombectomy (EVT) is the standard treatment for acute ischemic stroke due to internal carotid artery (ICA) or middle cerebral artery (MCA) M1 occlusion with a small ischemic core. However, the effect of EVT on acute stroke with a large ischemic core remains unclear. This study aimed to evaluate the association of EVT plus medical care versus medical care alone with outcomes in patients with acute stroke and a large ischemic core due to ICA or MCA M1 occlusion.

METHODS AND FINDINGS

PubMed, the Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov were searched from January 1, 2000 to September 25, 2024. There were no language restrictions. Randomized controlled trials (RCTs) of patients with acute stroke and a large ischemic core that compared EVT plus medical care versus medical care alone were evaluated. We computed the random-effects estimate based on the inverse variance method. Risk ratio (RR) with 95% confidence interval (CI) was used to measure outcomes of EVT plus medical care versus medical care alone. The primary outcome was functional independence, defined as modified Rankin Scale (mRS) of 0-2 at 90 days post-stroke; and the lead secondary outcome was reduced disability, defined as ordinal shift of mRS. Safety outcomes were requiring constant care or death (mRS 5-6), death, and early symptomatic intracranial hemorrhage (sICH). Grading of Recommendations Assessment, Development and Evaluations (GRADE) was used to evaluate summaries of evidence for the outcomes. We included six RCTs comprising 1870 patients (826 females [44.2%]) with acute stroke and a larger moderate or large ischemic core due to ICA or MCA M1 occlusion. All patients were nondisabled before stroke. Pooled results showed that at 90 days post-stroke, EVT plus medical care, compared with medical care alone, was associated with greater functional independence (RR 2.53, 95% CI [1.95, 3.29]; p  < 0.001; number needed to treat [NNT], 9, 95% CI [6,15]) and reduced disability (common odds ratio 1.63, 95% CI [1.38, 1.93]; p < 0.001; NNT, 4 [minimum possible NNT, 2; maximum possible NNT, 6]). EVT plus medical care, compared with medical care alone, was associated with a lower risk of requiring constant care or death (RR 0.74, 95% CI [0.66, 0.84]; p  <  0.001; NNT, 7, 95% CI [6,11]). EVT plus medical care, compared with medical care alone, was associated with a nonsignificantly higher proportion of patients with early symptomatic intracranial hemorrhage (RR 1.65, 95% CI [1.00, 2.70]; p  =  0.05). The rates of death were not significantly different between the EVT plus medical care and medical care alone groups (RR 0.86, 95% CI [0.72, 1.02]; p  =  0.08). Main limitations include variability in imaging definitions of large core and inclusion of both larger moderate and large cores in the analysis.

CONCLUSIONS

Among patients with acute stroke and a larger moderate or large ischemic core due to ICA or MCA M1 occlusion who were nondisabled before stroke, EVT plus medical care, compared with medical care alone, may be associated with improved functional independence, reduced disability, and reduced rates of severe disability or death at 90 days post-stroke. PROSPERO registration number: CRD42024514605.

Validation of a Novel Magnetic Resonance Imaging Biomarker of Infarct Severity to Predict Functional Outcome After Endovascular Thrombectomy

BACKGROUND

Endovascular thrombectomy (EVT) dramatically improves clinical outcomes, but the final infarct volume (FIV) on magnetic resonance imaging only accounts for a minority of the treatment effect. An imaging biomarker that more strongly correlates with post-EVT functional outcome would be helpful for clinical prognosis and serve as a surrogate outcome measure in trials of EVT-adjuvant therapies. Here, we aimed to validate a novel magnetic resonance imaging-based metric, infarct density, which leverages post-EVT apparent diffusion coefficient as a marker of infarct severity.

METHODS

A retrospective cohort was derived from a single-center prospective EVT registry. Consecutive patients treated with EVT for anterior circulation large vessel occlusion were included from 2018 to 2019 who achieved successful reperfusion (modified Thrombolysis in Cerebral Infarction ≥2b). Magnetic resonance imaging was performed 12 to 48 hours post-EVT and processed via RAPID to quantify FIV using the apparent diffusion coefficient <620 threshold. Lesion volume was also collected using an apparent diffusion coefficient <470 threshold, and infarct density was calculated as: (volume <470/volume <620)×100%. Good outcome was defined as ≤2 on the 90-day modified Rankin Scale. Multivariable logistic regression models quantified the association between clinical/imaging variables and outcome. Receiver operating characteristic analysis quantified model classification performance.

RESULTS

Of 319 patients treated with EVT, 272 met inclusion criteria. The mean age was 69±13 years, 41% were female, and 62% achieved a good outcome. After adjusting for clinical and radiographic factors, FIV (adjusted odds ratio, 0.99 per 1 mL [95% CI, 0.98-1.00]; P=0.03) and infarct density (adjusted odds ratio, 0.95 per 1% [95% CI, 0.94-0.97]; P<0.001) were both independently inversely associated with good outcome. The final model incorporating both FIV and infarct density achieved excellent classification performance (area under the curve, 0.87 [95% CI, 0.83-0.91]). Removing infarct density from the model diminished its performance (area under the curve, 0.83 [95% CI, 0.78-0.88]; P=0.01).

CONCLUSIONS

Apparent diffusion coefficient-based infarct density after EVT is independently associated with long-term outcome and provides greater prognostic information than FIV alone. Post-EVT infarct density may be useful in clinical care and as a surrogate outcome measure in trials of EVT-adjuvant therapies.

Establishing minimal clinically important differences and cut-off values for the lower limb motricity index and trunk control test in older patients with acute stroke: a prospective cohort study

OBJECTIVE

To establish the Minimal Clinically Important Differences (MCIDs) for lower limb strength measured by the Motricity Index (LLMI) and trunk function assessed by the Trunk Control Test (TCT) in the acute phase of stroke in older patients. Further, the study sought to determine the cutoff values predicting functional prognosis at discharge for both the LLMI and TCT.

METHODS

This prospective cohort study was conducted for older patients (≥65 years) admitted for acute stroke, receiving guideline-based stroke care that includes early rehabilitation. The LLMI and TCT were measured within 7 days of admission and at discharge. The MCID was derived from receiving operating characteristic curves, based on a ≥ 1 point shift in the modified Rankin Scale (mRS) from admission to discharge. A good functional prognosis at discharge was defined as an mRS score of ≤ 3.

RESULTS

A total of 201 older patients with acute stroke were included. The TCT achieved an MCID of 13 (area under the curve [AUC] = 0.704, 95% confidence interval [CI]: 0.633-0.775), whereas the LLMI lacked the precision to produce a significant MCID. The optimal cutoff points for predicting a good outcome were found to be an LLMI score of 65 (AUC = 0.770, 95% CI: 0.705-0.835) and a TCT score of 25 (AUC = 0.827, 95% CI: 0.768-0.887) upon admission.

CONCLUSIONS

This study identified a valid MCID for the TCT, failed to do so for the LLMI, and established cutoff values for both the LLMI and TCT that can predict good outcomes in older patients with acute stroke.

Association of Ischemic Core Hypodensity With Thrombectomy Treatment Effect in Large Core Stroke: A Secondary Analysis of the SELECT2 Randomized Controlled Trial

BACKGROUND

We aimed to determine whether extensive severe computed tomography (CT) hypodensity, representing blood-brain barrier injury, would be associated with a reduced benefit of endovascular therapy (EVT) in patients presenting with large core stroke.

METHODS

This study is an exploratory analysis of SELECT2 (Randomized Controlled Trial to Optimize Patient's Selection for Endovascular Treatment in Acute Ischemic Stroke), a randomized controlled trial of EVT versus medical management in patients with large ischemic core who presented to 31 comprehensive stroke centers across the United States, Canada, Europe, Australia, and New Zealand. Visible CT hypodensity was outlined, and a threshold of severe CT hypodensity was defined as the lower 99% CI of contralateral thalamic gray matter in Hounsfield units (HU). The association between the volume of severe CT hypodensity and modified Rankin Scale (mRS) score of 0 to 3 was evaluated using logistic regression models, with adjustment for age, National Institutes of Health Stroke Scale, total noncontrast CT core volume, and a volume-by-treatment interaction. The relationship between severe CT hypodensity volume and the probability of an mRS score of 0 to 3 was used to select clinically relevant volume cut points for further evaluation. The treatment effect of EVT versus medical management on independent ambulation and hemicraniectomy was assessed in 2 subgroups based on these volume cut points.

RESULTS

In 322 patients, the median CT density was 31 HU (interquartile range, 28-34). The selected threshold of severe CT hypodensity was 26 HU. The volume of ischemic core ≤26 HU (per 1 mL increase) was associated with lower odds of mRS score of 0 to 3 after EVT (adjusted odds ratio [aOR], 0.96 [95% CI, 0.94-0.99]), but not medical management (aOR, 1.01 [95% CI, 0.98-1.03]; Pinteraction<0.01). In 101 patients with ≥26 mL of severe CT hypodensity, EVT, compared with medical management, was not associated with mRS score of 0 to 3 (aOR, 0.98 [95% CI, 0.33-2.88]) and was associated with hemicraniectomy (≥26 mL: aOR, 3.45 [95% CI, 1.09-10.86] versus <26 mL: aOR, 0.74 [95% CI, 0.31-1.75]; Pinteraction=0.03), whereas among 221 patients with <26 mL of severe hypodensity EVT was associated with mRS score of 0 to 3 (aOR, 7.20 [95% CI, 3.55-15.47]; Pinteraction<0.01).

CONCLUSIONS

Severe hypodensity within large ischemic regions modifies the thrombectomy treatment effect and increases the likelihood of hemicraniectomy, independent of lesion volume.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03876457.

Impact of different doses of intravenous alteplase on neuroinjury biomarker levels in patients with acute ischemic stroke and stress hyperglycemia

Intravenous alteplase thrombolysis is a primary treatment for acute ischemic stroke (AIS), but the optimal dose remains uncertain in patients with stress hyperglycemia. This study aims to compare the changes in neuroinjury biomarker levels, as well as the efficacy and safety, between low-dose (0.6 mg/kg) and standard-dose (0.9 mg/kg) intravenous alteplase treatment in patients with AIS and stress hyperglycemia. This study included 150 patients with AIS and stress hyperglycemia, who were divided into a low-dose group (n = 78) and a standard-dose group (n = 72). Differences between the 2 groups were analyzed in terms of neuroinjury biomarkers (neuro-specific enolase, S100β, glial fibrillary acidic protein, myelin basic protein), neurological recovery (National Institutes of Health Stroke Scale score), clinical outcomes (modified Rankin Scale score), and the incidence of adverse events. Multivariate regression analysis was conducted to evaluate the relationship between the dose and a favorable prognosis (modified Rankin Scale ≤ 2). We found that, within 24 hours post-treatment, the levels of neuroinjury biomarkers (neuro-specific enolase, S100β, glial fibrillary acidic protein, myelin basic protein) were significantly lower in the low-dose group compared with the standard-dose group (P < .05), and the improvement in National Institutes of Health Stroke Scale scores was more pronounced (P < .01). Three months after thrombolysis, the favorable prognosis rate in the low-dose group was 63.5%, higher than the 47.2% in the standard-dose group, with a near-significant difference (P = .09). Multivariate regression analysis indicated that low-dose treatment was an independent protective factor for a favorable prognosis (odds ratio = 2.34, 95% confidence interval = 1.29-4.23, P = .006). There were no significant differences in the incidence of adverse events between the 2 groups, though the proportion of mild bleeding was slightly lower in the low-dose group compared with the standard-dose group. Low-dose intravenous alteplase thrombolysis demonstrates more significant neuroprotective effects in patients with AIS and stress hyperglycemia, promoting neurological recovery and improving long-term prognosis without increasing the risk of adverse events. Low-dose thrombolysis may be a safer and more effective treatment option, but its efficacy and safety require further validation through large-scale, randomized controlled trials.

Association of baseline infarct size, reperfusion grade and intracranial hemorrhage in patients undergoing thrombectomy

BACKGROUND

Better reperfusion status results in smaller infarct volumes and better outcomes after thrombectomy. However, if large tissue volumes are already infarcted at baseline, reperfusion might also increase the risk of intracranial hemorrhage. This study aims to investigate the interaction between reperfusion status, baseline ischemic changes, and intracranial hemorrhage following thrombectomy.

METHODS

Retrospective analysis of the ESCAPE-NA1 randomized trial. Unadjusted and adjusted logistic regression models were used to estimate the associations of Alberta Stroke Program Early CT Score (ASPECTS) and expanded Treatment In Cerebral Infarction (eTICI) score on post-treatment hemorrhage. Treatment effect modification was assessed by including multiplicative interaction terms (ASPECTS*eTICI) in these models.

RESULTS

A total of 1077 patients were included. Median age was 70.8 (IQR 60.7-79.7) and 543 (50.4%) were female. Any intracranial hemorrhage on 24-hour follow-up imaging occurred in 368/1077 (34.2%) patients. There was evidence of modification of the effect of final angiogram eTICI score on any intracranial hemorrhage by baseline ASPECTS (P=0.008). Marginal probabilities showed increased hemorrhage risk for patients with low ASPECTS with increasing final eTICI scores. This association was reversed in patients with small baseline ischemic changes and successful reperfusion. There was no association with symptomatic intracranial hemorrhage or parenchymal hematoma.

CONCLUSION

The association of post-thrombectomy reperfusion status and post-treatment hemorrhage may be modified by the extent of baseline ischemia. Reperfusion is associated with reduced risk of hemorrhage in patients with small baseline infarcts, but increased hemorrhage risk in patients with extensive ischemic changes at baseline. However, no significant association was found with symptomatic intracranial hemorrhage or parenchymal hematoma.

TRIAL REGISTRATION NUMBER

NCT02930018.

Combined effect of ASPECTS and age on outcome of patients with large core infarction treated with mechanical thrombectomy

BACKGROUND

Despite the remarkable effectiveness of endovascular treatment (EVT), recent randomized controlled trials indicate that up to half of patients with large core infarction have a very poor outcome (modified Rankin Scale score 5-6 at 90 days). This study investigates the combined effect of Alberta Stroke Program Early CT Score (ASPECTS) and age on very poor outcome in patients with large core infarction treated with EVT.

METHODS

This subanalysis of the MAGIC registry, which is a prospective, multicenter cohort study of early treatment in acute stroke, focused on patients with ASPECTS ≤5 presenting within 24 hours of stroke onset and receiving CT followed by EVT from November 1, 2021 to February 8, 2023. Multivariable logistic regression was used to investigate the independent and joint association of ASPECTS and age with very poor outcome.

RESULTS

Among the 490 patients (57.3% men; median (IQR) age 69 (59-78) years), very poor outcome occurred more frequently in those with lower ASPECTS (65.2% in ASPECTS 0-2 vs 43.4% in ASPECTS 3-5; P<0.001). The predictive value of successful recanalization for very poor outcome was significant in patients with ASPECTS 3-5 (P=0.010), but it diminished in those with ASPECTS 0-2 (P=0.547). Compared with patients with ASPECTS 3-5 and age ≤69 years, the risk of a very poor outcome increased incrementally in those with lower ASPECTS, advanced age, or both (P<0.05). Graphical plot analysis showed a significantly lower probability of very poor outcome in younger patients (≤69 years) compared with older patients (>69 years) across all ASPECTS points.

CONCLUSION

These findings suggest prioritizing young patients as candidates for EVT in those with ASPECTS 0-2.

Computed tomography perfusion as an early predictor of malignant cerebral infarction

INTRODUCTION

Malignant middle cerebral artery infarction (MCI) needs rapid intervention. This study aimed to enhance the prediction of MCI using computed tomography perfusion (CTP) with varied quantitative benchmarks.

MATERIALS AND METHODS

We retrospectively analyzed 253 patients from a single-center registry presenting with acute, severe, proximal large vessel occlusion studied with whole-brain CTP imaging at hospital arrival within the first 24 h of symptoms-onset. MCI was defined by clinical and imaging criteria, including decreased level of consciousness, anisocoria, death due to cerebral edema, or need for decompressive craniectomy, together with midline shift ⩾6 mm, or infarction of more than 50% of the MCA territory. The predictive accuracy of baseline ASPECTS and CTP quantifications for MCI was assessed by receiver operating characteristic (ROC) area under the curve (AUC) while F-score was calculated as an indicator of precision and sensitivity.

RESULTS

Sixty-three out of 253 patients (25%) fulfilled MCI criteria and had worse clinical and imaging results than the non-MCI group. The capacity to predict MCI was lower for baseline ASPECTS (AUC 0.83, F-score 0.52, Youden's index 6), than with perfusion-based measures: relative cerebral blood volume threshold <40% (AUC 0.87, F-score 0.71, Youden's index 34 mL) or relative cerebral blood flow threshold <35% (AUC 0.87, F-score 0.62, Youden's index 67 mL). CTP based on rCBV measurements identified twice as many MCI as baseline CT ASPECTS.

DISCUSSION AND CONCLUSION

CTP-based quantifications may offer enhanced predictive capabilities for MCI compared to non-contrast baseline CT ASPECTS, potentially improving the monitoring of severe ischemic stroke patients at risk of life-threatening edema and its treatment.

The number of recanalization attempts, procedure time and endovascular therapy outcomes in acute large core stroke patients

INTRODUCTION

Landmark thrombectomy trials demonstrated improved functional outcomes after endovascular therapy (EVT) for large core strokes (LCSs). This study explored the impact of recanalization attempts and procedure time (PT) on outcomes in LCS patients.

PATIENTS AND METHODS

This was a retrospective study of patients with LCSs who underwent EVT from a prospective multicentre cohort. LCS was defined as an Alberta Stroke Program Early Computed Tomography Score of 0 to 5. Patients were divided into 6 groups (unsuccessful reperfusion [modified Thrombolysis in Cerebral Infarction Scale (mTICI) 0-2a] and successful reperfusion [mTICI, 2b/3]) after 1, 2, 3, 4, or >4 attempts. The primary outcome was a favorable 90-day mRS score of 0-3. Secondary outcomes included mRS 0-4, 90-day mortality, and 48-hour rates of symptomatic (sICH) and any intracranial hemorrhage (aICH).

RESULTS

A total of 447 patients were analysed. 388 with successful reperfusion, 59 without.Successful reperfusion during the first 3 passes increased the odds of favourable functional outcomes [attempt 1: aOR, 4.454 (1.723-11.514),p=0.002; 2: aOR, 3.762 (1.437-9.847),p=0.07; or 3: aOR, 3.619 (1.254-10.440),p=0.017] and decreased mortality at 90 days [(attempt 1: aOR, 0.336 (0.155-0.727),p=0.006; 2: aOR, 0.346 (0.160-0.746),p=0.007; or 3: aOR, 0.395 (0.164-0.953),p=0.039]. A shorter PT increased the odds of a favourable functional outcome [aOR, 0.991 (0.985-0.997),p=0.002]. PT may reduce the association between the number of attempts and patient outcomes. No associations were found between the number of attempts and sICH or aICH, whereas there was an increasing trend in the proportion of aICH or sICH when the number of attempts was more than two.

CONCLUSION

In patients with LCSs who underwent EVT, successful reperfusion within the first 3 attempts and a shorter PT were associated with favourable functional outcomes. However, the effect size of the association between the number of attempts and clinical outcomes may gradually decrease with extension of the PT.

The apparent diffusion coefficient color Map for evaluating a large ischemic core

INTRODUCTION

Our previous work demonstrated that evaluating large ischemic cores using the apparent diffusion coefficient (ADC) could predict EVT outcomes, with the most frequent ADC (peak ADC) ≥520×10-6 mm2/s associated with better clinical results. Since the degree of ADC reduction reflects the severity of ischemic stress, this study aimed to assess the utility of an ADC color map in visualizing this stress.

PATIENTS AND METHODS

This retrospective cohort study included consecutive patients with a low Alberta Stroke Program Early Computed Tomography Score (ASPECTS) using diffusion-weighted imaging (DWI) who underwent successful EVT recanalization between April 2014 and March 2023. To create a visual representation of ischemic stress, we assigned different colors to diffusion-weighted image (DWI) lesions based on their ADC values: ≥520×10-6 mm2/s, 520-440×10-6 mm2/s, and <440×10-6 mm2/s. We compared patients with peak ADC ≥520×10-6 mm2/s to those with lower peak ADC to identify factors associated with the higher value.

RESULTS

A total of 78 patients were enrolled, with 34 having a peak ADC ≥520×10-6 mm2/s. The optimal ratio for discriminating peak ADC ≥520×10-6 mm2/s was found to be 60 % for the volume of the lesion with ADC ≥520×10-6 mm2/s (ADC520) relative to the total DWI lesion volume. This ratio demonstrated a sensitivity of 86 % and a specificity of 82 %.

DISCUSSION AND CONCLUSION

The ADC color map effectively portrays the depth of ischemic stress. A large ischemic core with an ADC520/DWI ratio >60 % may be salvageable with EVT. This approach offers a visual means for assessing EVT suitability in acute large ischemic stroke.

[Acute ischemic stroke treatment]

Intravenous thrombolysis (IVT) and endovascular therapy (EVT) are the cornerstones of acute ischemic stroke treatment. While IVT has been an integral part of acute therapy since the mid-1990s, EVT has evolved as one of the most effective treatments in medicine over the past decade. Traditionally, systemic thrombolysis has been performed with alteplase (rtPA). More recently, tenecteplase (TNK) has been shown to be non-inferior to rtPA. TNK has some pharmacological advantages over rtPA and may lead to earlier recanalization, particularly in large vessel occlusions. All recanalization therapies are highly time dependent. To ensure rapid treatment, standard operating procedures (SOPs) should be established and followed in clinical practice. The optimal time window for IVT is 4.5 h after symptom onset and can be extended up to 9 h using specialized imaging techniques. For EVT, studies suggest a time window up to 24 h after symptom onset. In some cases, EVT has been successfully performed beyond this time window. To select patients for EVT, advanced imaging identifying salvageable brain tissue might be necessary. Even in large ischemic stroke, EVT can still improve outcome. Compared to EVT, IVT requires fewer technical and human resources, so more stroke patients can potentially be treated. In contrast, EVT requires highly trained personnel with sophisticated equipment and can, therefore, only be performed in specialized centers. Both procedures should be combined within the 4.5 h time window for patients without contraindications.

Impact of time from symptom onset to puncture, and puncture to reperfusion, in endovascular therapy in the late time window (>6 h)

BACKGROUND

Increased time from symptom onset to puncture (TSOP) and time from puncture to reperfusion (TPTR) are associated with worse outcome in ischemic stroke patients treated with endovascular therapy (EVT) in the early time window (<6 h). However, these associations are less described in the late window (>6 h), where patients may benefit from EVT because of a more favorable imaging profile (late window paradox). We sought to compare the effect of these timeframes between these two periods on efficacy and safety outcomes.

METHODS

The ETIS (Endovascular Treatment in Ischemic Stroke) registry is an ongoing, prospective, observational study in 21 centers that perform EVT in France. We included adult patients with an anterior occlusion, successfully treated by EVT (modified treatment in cerebral ischemia (mTICI) 2b-3) between January 2015 and June 2023, with a known time of stroke onset. The cohort was divided into two groups according to the TSOP (⩽6 h vs >6 h). Primary outcome was favorable outcome (modified Rankin Scale 0-2 at 90 days).

RESULTS

In total, 7516 patients were included, with 5936 patients being treated ⩽6 h and 1580 >6 h. In the early window, TSOP and TPTR were associated with worse outcomes at 90 days (adjusted odds ratio (aOR) = 0.68 per hour; 95% confidence interval (CI) = 0.64-0.73; p < 0.001 and aOR = 0.92 per 10-min increment; 95% CI = 0.90-0.94, p < 0.001, respectively). TSOP was not associated with worse outcomes at 90 days in the late window (p = 0.955), but TPTR was associated with worse outcomes (aOR = 0.91 per 10-min increment; 95% CI = 0.86-0.96, p = 0.001), every 10 additional minutes in TPTR being associated with a 1.7% (95% CI = 0.6-2.7) decreased probability of favorable outcome.

CONCLUSION

Only EVT procedural time is associated with unfavorable outcomes at 90 days in late window patients. These results highlight how the late window paradox may end at the start of EVT and underscore the need for timely management, particularly for the EVT, even for late window patients with a presumed more favorable imaging profile.

Real-world outcomes after endovascular thrombectomy in patients with large infarct cores

Patients with large infarct cores on imaging at hospital presentation who are then treated with endovascular thrombectomy achieved functional independence rates ranging from 14%-30% in randomised controlled trials. We describe our 'real-world' experience with these patients. About one-third were independent at day 90, similar to trial results. This was associated with higher rates of complications and double the length of stay.

Insights into vessel perforations during thrombectomy: Characteristics of a severe complication and the effect of thrombolysis

INTRODUCTION

Thrombectomy complications remain poorly explored. This study aims to characterize periprocedural intracranial vessel perforation including the effect of thrombolysis on patient outcomes.

PATIENTS AND METHODS

In this multicenter retrospective cohort study, consecutive patients with vessel perforation during thrombectomy between January 2015 and April 2023 were included. Vessel perforation was defined as active extravasation on digital subtraction angiography. The primary outcome was modified Rankin Scale (mRS) at 90 days. Factors associated with the primary outcome were assessed using proportional odds models.

RESULTS

459 patients with vessel perforation were included (mean age 72.5 ± 13.6 years, 59% female, 41% received thrombolysis). Mortality at 90 days was 51.9% and 16.3% of patients reached mRS 0-2 at 90 days. Thrombolysis was not associated with worse outcome at 90 days. Perforation of a large vessel (LV) as opposed to medium/distal vessel perforation was independently associated with worse outcome at 90 days (aOR 1.709, p = 0.04) and LV perforation was associated with poorer survival probability (HR 1.389, p = 0.021). Patients with active bleeding >20 min had worse survival probability, too (HR 1.797, p = 0.009). Thrombolysis was not associated with longer bleeding duration. Bleeding cessation was achieved faster by permanent vessel occlusion compared to temporary measures (median difference: 4 min, p < 0.001).

DISCUSSION AND CONCLUSION

Vessel perforation during thrombectomy is a severe and frequently fatal complication. This study does not suggest that thrombolysis significantly attributes to worse prognosis. Prompt cessation of active bleeding within 20 min is critical, emphasizing the need for interventionalists to be trained in complication management.

Multiphase CTA vs. MRA collateral map for predicting functional outcomes after acute ischemic stroke

PURPOSE

To compare the prognostic abilities of multiphase CT angiography (mCTA) and multiphase MR angiography (MRA) collateral map in acute anterior circulation ischemic stroke.

METHODS

This secondary analysis of a prospective observational study included data from participants with acute ischemic stroke due to steno-occlusion of the internal carotid artery and/or middle cerebral artery within 8 h of symptom onset between January 1, 2016, and March 31, 2021. The intermethod agreement of the collateral scores (CSs) from mCTA and the collateral perfusion scores (CPSs) from the MRA collateral map was analyzed. Multiple logistic regression analyses were conducted to determine the prognostic value of mCTA and MRA collateral maps.

RESULTS

169 participants (106 men and 63 women, mean age 69 years ± 13) were included. The agreement between the CSs of mCTA and the CPSs of the MRA collateral map (weighted kappa = 0.44, 95% confidence interval [CI]: 0.37-0.52) of 168 participants was moderate. Younger age (Odds ratio [OR], 0.51; 95% CI, 0.34-0.76; p = 0.001), lower baseline NIHSS scores (OR, 0.89; 95% CI, 0.81-0.99; p = 0.024), CPS 4 (OR, 36.66; 95% CI, 1.79-750.29; p = 0.019) and CPS 5 (OR, 144.10; 95% CI, 1.11-18788.93; p = 0.046) on the MRA collateral map, and successful reperfusion (OR, 9.63; 95% CI, 3.00-30.94; p < 0.001) were independently associated with favorable functional outcomes.

CONCLUSIONS

Only the MRA collateral map demonstrated clinical prognostic value in acute anterior circulation ischemic stroke patients, demonstrating the superiority of the MRA collateral map over mCTA in collateral assessment.

Machine learning, clinical-radiomics approach with HIM for hemorrhagic transformation prediction after thrombectomy and treatment

Background

This study aimed to develop a clinical-radiomics model using hyperattenuated imaging markers (HIM), characterized by hyperattenuation on head non-contrast computed tomography immediately after thrombectomy, to predict the risk of hemorrhagic transformation (HT) in patients undergoing endovascular mechanical thrombectomy (MT).

Methods

A total of 159 consecutive patients with HIM were screened immediately after MT for inclusion. The datasets were randomly divided into training and test cohorts at a ratio of 8:2. An optimal machine learning (ML) algorithm was used for model development. Subsequently, models for clinical, radiomics, and clinical-radiomics were developed. The performance of the models was measured using receiver operating characteristic (ROC) and decision curve analyses (DCA). The interpretability and predictor importance of the model were analyzed using Shapley additive explanations.

Results

Of the 159 patients, 100 (62.9%) exhibited HT. The support vector machine (SVM) was the optimal ML algorithm for constructing the models. In predicting HT, the areas under the curve (AUCs) of the clinical model were 0.918 (95% confidence interval [CI] = 0.869-0.966) in the training cohort and 0.854 (95% CI = 0.724-0.984) in the test cohort. The AUCs of the radiomics model were 0.869 (95% CI = 0.802-0.936) and 0.829 (95% CI = 0.668-0.990), while those of the clinical-radiomics model were 0.944 (95% CI = 0.905-0.984) and 0.925 (95% CI = 0.832-1.000).

Conclusion

The suggested clinical-radiomics model based on HIM is a reliable method that can provide a risk evaluation of HT in individuals undergoing MT.

Effectiveness and safety of bridging therapy and endovascular therapy in patients with large cerebral infarctions: from ANGEL-ASPECT

BACKGROUND AND PURPOSE

The benefits of thrombolytic therapy before endovascular thrombectomy in cases of acute ischaemic stroke, with a large infarction volume, remain unclear. This analysis aims to evaluate the effectiveness and safety of bridging therapy and endovascular therapy among patients with large cerebral infarctions.

METHODS

In this post-hoc analysis of the multicentre prospective study of ANGEL-ASPECT (Acute Anterior Circulation Large Vessel Occlusive Patients with a Large Infarct Core), participants were divided into two groups: an endovascular therapy group and a bridging therapy group. The primary outcome was the modified Rankin Scale (mRS) score at 90 days. The primary safety outcome was symptomatic intracranial haemorrhage. Ordinal logistic regression was performed to compare the primary endpoint between the two groups. Subgroup analyses were conducted to further explore potential risk factors associated with the outcomes.

RESULTS

122 patients were included, of whom 77 (63%) underwent endovascular therapy and 45 (37%) underwent bridging therapy. The median scores on mRS at 90 days of the bridging therapy group and the endovascular therapy group were 3 (2-5) and 4 (2-6), with no significant differences (common OR 1.36; 95% CI 0.71 to 2.61). Symptomatic intracranial haemorrhage was reported in three patients who were in the endovascular and bridging therapy groups (relative risk (RR) 1.71; 95% CI 0.36 to 8.12). The mortality between two groups did not differ (RR 0.75; 95% CI 0.37 to 1.54).

CONCLUSIONS

Our study indicated that endovascular therapy alone might be a viable option for patients with large cerebral infarctions, displaying no noticeable disparity in outcomes compared with bridging therapy.

Endovascular Thrombectomy for Extracranial Internal Carotid Artery Occlusions With Large Ischemic Strokes: Insights From the SELECT2 Trial

BACKGROUND AND OBJECTIVES

Although previous trials have established the efficacy and safety of endovascular thrombectomy (EVT) in large ischemic core strokes, most of them excluded patients with extracranial internal carotid artery (e-ICA) occlusion. We aimed to compare outcomes in patients with e-ICA occlusion and large ischemic core infarcts treated with EVT vs medical management (MM).

METHODS

This was a secondary analysis of the SELECT2 trial, a randomized controlled trial conducted at 31 international sites. Adult patients with proximal intracranial anterior circulation large ischemic strokes, defined as Alberta Stroke Program Early CT Score (ASPECTS) 3-5 on noncontrast CT or ischemic core ≥50 mL on CT-perfusion/magnetic resonance-diffusion imaging, and concomitant e-ICA occlusion were selected. The primary outcomes were the distribution of modified Rankin Scale (mRS) score at 90-day follow-up and symptomatic intracranial hemorrhage (sICH).

RESULTS

Among 352 enrolled patients, 62 (17.6%) with e-ICA occlusions were included. Of those 62 patients, 37 received EVT (median [interquartile range (IQR)] age, 65 [58-71] years; 15 women [38.5%]) and 25 received MM (median [IQR] age, 66 [61-71] years; 7 women [28%]). ASPECTS (EVT: 5 [3-5] vs MM: 5 [4-5]) and ischemic core volume (EVT: 100 [69-134] mL vs MM: 103 [78-135] mL) were similar between groups. The successful reperfusion rate with EVT was 64.9%. Patients receiving EVT demonstrated significantly better functional outcomes (adjusted generalized odds ratio 2.51; 95% CI 1.43-4.39; p = 0.001) and a higher proportion of patients achieving 90-day independent ambulation (EVT: 37.8% vs MM: 8%; adjusted relative ratio [aRR] 4.58; 95% CI 1.18-17.79; p = 0.037) and functional independence (EVT: 21.6% vs MM: 8%; aRR 2.16; 95% CI 0.53-8.83; p = 0.285). Furthermore, no heterogeneity of EVT benefit was observed by the presence or absence of e-ICA occlusion (p-interaction = 0.248). There were no sICH or parenchymal hemorrhage type 2 events in either group, and mortality was similar in the 2 groups (aRR 0.75; 95% CI 0.39-1.45; p = 0.388).

DISCUSSION

Among patients with e-ICA occlusions and large ischemic core stroke, EVT was associated with better functional outcomes without significant safety concerns when compared with MM. Our findings suggest that EVT in these patients is beneficial, while the optimal treatment of the extracranial carotid occlusion remains unclear.

TRIAL REGISTRATION INFORMATION

Name of the trial: SELECT2 trial. Registration number: ClinicalTrials.gov Identifier: NCT03876457. Date of registration submission: August 3, 2019. Date of first patient enrollment: November 10, 2019.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that for patients with large core acute ischemic stroke and concomitant e-ICA occlusion, EVT is associated with better functional outcome at 90 days compared with MM alone.

Llama 3.1 405B Is Comparable to GPT-4 for Extraction of Data from Thrombectomy Reports-A Step Towards Secure Data Extraction

PURPOSE

GPT‑4 has been shown to correctly extract procedural details from free-text reports on mechanical thrombectomy. However, GPT may not be suitable for analyzing reports containing personal data. The purpose of this study was to evaluate the ability of the large language models (LLM) Llama3.1 405B, Llama3 70B, Llama3 8B, and Mixtral 8X7B, that can be operated offline, to extract procedural details from free-text reports on mechanical thrombectomies.

METHODS

Free-text reports on mechanical thrombectomy from two institutions were included. A detailed prompt was used in German and English languages. The ability of the LLMs to extract procedural data was compared to GPT‑4 using McNemar's test. The manual data entries made by an interventional neuroradiologist served as the reference standard.

RESULTS

100 reports from institution 1 (mean age 74.7 ± 13.2 years; 53 females) and 30 reports from institution 2 (mean age 72.7 ± 13.5 years; 18 males) were included. Llama 3.1 405B extracted 2619 of 2800 data points correctly (93.5% [95%CI: 92.6%, 94.4%], p = 0.39 vs. GPT-4). Llama3 70B with the English prompt extracted 2537 data points correctly (90.6% [95%CI: 89.5%, 91.7%], p < 0.001 vs. GPT-4), and 2471 (88.2% [95%CI: 87.0%, 89.4%], p < 0.001 vs. GPT-4) with the German prompt. Llama 3 8B extracted 2314 data points correctly (86.1% [95%CI: 84.8%, 87.4%], p < 0.001 vs. GPT-4), and Mixtral 8X7B extracted 2411 (86.1% [95%CI: 84.8%, 87.4%], p < 0.001 vs. GPT-4) correctly.

CONCLUSION

Llama 3.1 405B was equal to GPT‑4 for data extraction from free-text reports on mechanical thrombectomies and may represent a data secure alternative, when operated locally.

Deep learning-based classification of diffusion-weighted imaging-fluid-attenuated inversion recovery mismatch

The presence of a diffusion-weighted imaging (DWI)-fluid-attenuated inversion recovery (FLAIR) mismatch holds potential value in identifying candidates for recanalization treatment. However, the visual assessment of DWI-FLAIR mismatch is subject to limitations due to variability among raters, which affects accuracy and consistency. To overcome these challenges, we aimed to develop and validate a deep learning-based classifier to categorize the mismatch. We screened consecutive acute ischemic stroke patients who underwent DWI and FLAIR imaging from a four stroke centers. Two centers were used for model development and internal testing (derivation cohort), while two independent centers served as external validation cohorts. We developed Convolutional Neural Network-based classifiers for two binary classifications: DWI-FLAIR match versus non-match (Label Set I) and match versus mismatch (Label Set II). A total of 2369 patients from the derivation set and 679 patients from two external validation sets (350 and 329 patients) were included in the analysis. For Label Set I, the internal test set AUC was 0.862 (95% CI 0.841-0.884, with external validation AUCs of 0.829 (0.785-0.873) and 0.835 (0.790-0.879). Label Set II showed higher performance with internal test AUC of 0.934 (0.911-0.957) and external validation AUCs of 0.883 (0.829-0.938) and 0.913 (0.876-0.951). A deep learning-based classifier for the DWI-FLAIR mismatch can be used to diminish subjectivity and support targeted decision-making in the treatment of acute stroke patients.

Exploring the use of ChatGPT in predicting anterior circulation stroke functional outcomes after mechanical thrombectomy: a pilot study

BACKGROUND

Accurate prediction of functional outcomes is crucial in stroke management, but this remains challenging.

OBJECTIVE

To evaluate the performance of the generative language model ChatGPT in predicting the functional outcome of patients with acute ischemic stroke (AIS) 3 months after mechanical thrombectomy (MT) in order to assess whether ChatGPT can used to be accurately predict the modified Rankin Scale (mRS) score at 3 months post-thrombectomy.

METHODS

We conducted a retrospective analysis of clinical, neuroimaging, and procedure-related data from 163 patients with AIS undergoing MT. The agreement between ChatGPT's exact and dichotomized predictions and actual mRS scores was assessed using Cohen's κ. The added value of ChatGPT was measured by evaluating the agreement of predicted dichotomized outcomes using an existing validated score, the MT-DRAGON.

RESULTS

ChatGPT demonstrated fair (κ=0.354, 95% CI 0.260 to 0.448) and good (κ=0.727, 95% CI 0.620 to 0.833) agreement with the true exact and dichotomized mRS scores at 3 months, respectively, outperforming MT-DRAGON in overall and subgroup predictions. ChatGPT agreement was higher for patients with shorter last-time-seen-well-to-door delay, distal occlusions, and better modified Thrombolysis in Cerebral Infarction scores.

CONCLUSIONS

ChatGPT adequately predicted short-term functional outcomes in post-thrombectomy patients with AIS and was better than the existing risk score. Integrating AI models into clinical practice holds promise for patient care, yet refining these models is crucial for enhanced accuracy in stroke management.

Workload and clinical impact of MRI-based extension of reperfusion therapy time window in acute ischaemic stroke-a prospective single-centre study

Current European Stroke Organisation (ESO) guidelines recommend extended time window reperfusion therapies (4.5-9 h for thrombolysis, 6-24 h for thrombectomy) based on advanced imaging. However, the workload and clinical benefit of this strategy on a population basis are not known. To determine the caseload, treatment rates, and outcomes in the extended as compared to the standard time windows. All consecutive ischaemic stroke patients within 24 h of last known well between 1st March 2021 and 28th February 2022 were included in a prospective single-centre study. Treatment eligibility in the extended time windows or wake-up strokes recognized within 4 h was based on current ESO guideline criteria using MRI DWI-PWI or DWI-FLAIR mismatch. MRI was only available during working hours (8-20 h); otherwise, CT/CTA was used. Clinical outcome in treated patients was assessed at three months. Among the 777 admitted patients, 252 (32.4%) had MRI. The thrombolysis rate was 119/304 (39.1%) in standard and 14/231 (6.1%) in the extended time window. The thrombectomy rate was 34/386 (8.8%) in standard and 15/391 (3.8%) in the extended time window. Independent clinical outcomes (mRS ≤ 2) were not statistically different in early and late-treated patients both for thrombolysis (48% vs. 28.6%, p = 0.25) and thrombectomy (38.4% vs. 33.3%, p = 0.99). Even with a limited availability of advanced imaging extending therapeutic time windows resulted in an 11.7% increase in thrombolysis and a 44% increase in thrombectomy with comparable clinical outcomes in early and late-treated patients at the price of a twofold burden in clinical and advanced imaging screening.

Methylprednisolone as Adjunct to Thrombectomy for Acute Intracranial Internal Carotid Artery Occlusion Stroke: Post Hoc Secondary Analysis of the MARVEL Randomized Clinical Trial

Importance

Patients with acute ischemic stroke (AIS) due to intracranial internal carotid artery (ICA) occlusion often have poor functional outcomes despite undergoing endovascular thrombectomy (EVT).

Objective

To investigate the effectiveness and safety associated with intravenous methylprednisolone as adjunctive treatment to EVT for patients with AIS due to intracranial ICA occlusion.

Design, Setting, and Participants

This was a post hoc analysis of the MARVEL randomized, double-blind, placebo-controlled clinical trial conducted from February 9, 2022, to June 30, 2023, at 82 stroke centers across China with a 3-month follow-up. The primary trial enrolled 1680 patients with large vessel occlusion within 24 hours from last known well time in the intracranial ICA, the first segment of the middle cerebral artery (M1), or the second segment of the middle cerebral artery (M2), of whom 579 patients had intracranial ICA occlusion.

Intervention

Intravenous methylprednisolone, 2 mg/kg/d (maximum dose, 160 mg) for 3 days plus EVT vs placebo plus EVT.

Main Outcomes and Measures

The primary outcome was independent ambulation at 90 days, defined as a score of 0 to 3 on the modified Rankin Scale (range, 0 [no symptoms] to 6 [death]). Safety outcomes included death within 90 days, symptomatic intracranial hemorrhage (sICH) within 48 hours, and decompressive hemicraniectomy to relieve midline-shift and intracranial pressure after EVT.

Results

Among 579 patients (median age, 69.0 years [IQR, 59.0-76.0 years]; 338 men [58.4%]), there were 286 patients in the methylprednisolone group and 293 patients in the placebo group. The proportion of patients who achieved 90-day independent ambulation was significantly higher in the methylprednisolone group than in the placebo group (151 of 284 [53.2%] vs 125 of 293 [42.7%]; adjusted risk ratio [RR], 1.27 [95% CI, 1.07-1.52]; P = .007). The incidence of sICH was lower in the methylprednisolone group than in the placebo group (26 of 277 [9.4%] vs 45 of 290 [15.5%]; adjusted RR, 0.55 [95% CI, 0.35-0.87]; P = .01). The rate of decompressive hemicraniectomy was lower in the methylprednisolone group compared with the placebo group (16 of 286 [5.6%] vs 29 of 293 [9.9%]; adjusted RR, 0.54 [95% CI, 0.30-0.98]; P = .04). No significant difference was observed in mortality between groups (methylprednisolone, 92 of 284 [32.4%] vs placebo, 111 of 239 [37.9%]; adjusted RR, 0.84 [95% CI, 0.67-1.05]; P = .13).

Conclusions and Relevance

In this secondary analysis of a randomized clinical trial of intravenous methylprednisolone vs placebo for patients with intracranial ICA occlusion undergoing EVT, intravenous methylprednisolone was associated with improved ambulation. These findings suggest that the use of intravenous methylprednisolone as an adjunct to EVT may hold promise as a treatment option for patients with AIS due to intracranial ICA occlusion.

Trial registration

ChiCTR.org.cn Identifier: ChiCTR2100051729.