Early ischemic change on CT versus diffusion-weighted imaging for patients with stroke receiving intravenous recombinant tissue-type plasminogen activator therapy: stroke acute management with urgent risk-factor assessment and improvement (SAMURAI) rt-PA registry

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.

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.

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.

Endovascular treatment for isolated cervical internal carotid artery occlusion: ETIICA study

INTRODUCTION

Evidence regarding the benefit of endovascular therapy (EVT) in patients with acute ischemic stroke (AIS) due to isolated cervical internal carotid artery occlusion (c-ICA-O) is lacking. We assessed the outcomes and safety of EVT in patients with isolated c-ICA-O.

METHODS

Retrospective multicenter cohort study of patients with an AIS due to isolated c-ICA-O, within 24-h since last-seen-well. Comparisons were made between EVT and best medical therapy (BMT). The primary outcome was 3-months modified Rankin Scale (mRS) ordinal shift. Secondary outcomes included 3-month favorable outcome (mRS 0-2, or return to pre-stroke mRS), symptomatic intracranial hemorrhage (sICH) and any parenchymal hemorrhage. Outcomes were compared combining inverse probability of treatment weighting with regression models and propensity score matching (PSM) as sensitivity analysis.

RESULTS

We analyzed 998 patients (66.2% male, mean age 71.1 ± 13.2 years). 487 (48.8%) patients received EVT and 511 (51.2%) received BMT. Patients receiving EVT had a higher admission NIHSS [13 (7-18) vs 5 (2-13)] compared to BMT. There was no difference between EVT and BMT groups in 3-month mRS shift (adjusted common odds ratio [OR], 1.01 [95% CI 0.76-1.34]) and favorable outcome (adjusted OR [aOR] 1.16 [95% CI 0.84-1.60]). No patient (0%) in the BMT group had sICH versus 1.6% in the EVT group. Parenchymal hemorrhage was numerically higher in EVT patients (2.7% vs 0.6%; aOR 3.85 [95% CI 0.98-15.23]). PSM analysis revealed similar results.

DISCUSSION AND CONCLUSION

In patients with isolated c-ICA-O, EVT was associated with similar odds of disability and intracranial bleeding compared to BMT. Randomized-controlled clinical trials in patients with isolated c-ICA-O are warranted.

Quantitative Evaluation of Ischemic Core Volume in GE's CT Perfusion Imaging Analysis Software and Its Relationship to Alberta Stroke Program Early CT Score

Objective

Computed tomography (CT) and magnetic resonance imaging of cerebral perfusion are useful in determining the indication of mechanical thrombectomy (MT) for acute ischemic stroke. RAPID (iSchemaView, Menlo Park, CA, USA) is the most common software for analyzing brain perfusion images worldwide, but various other software are also available. The optimal threshold value for each software is different, and each has its characteristics. This study investigated the relationship between the quantitative evaluation of ischemic core volume (ICV) and the Alberta Stroke Program Early CT Score (ASPECTS) using CT Perfusion 4D (GE Healthcare Inc., Milwaukee, WI, USA), a software used in our hospital.

Methods

Among patients who underwent MT between April 2015 and February 2023, those with modified Rankin Scale: 0-2, obstruction by embolic mechanism, and thrombolysis in cerebral infarction: 2b or higher were selected retrospectively. Patients with middle cerebral artery M1 segment (M1) and internal carotid artery (ICA) occlusions (90 and 46 patients) were included. We quantitatively analyzed ICV at relative cerebral blood flow (rCBF) <20% and cerebral blood volume (CBV) <1 mL/100 g and evaluated the relationship with ASPECTS scores in 3 groups: M1 + ICA, M1, and ICA occlusion groups.

Results

The median ICV was rCBF <20%: 44.7 cm3 and CBV <1 mL/100 g: 34.6 cm3, and there was no statistically significant difference between the 2 groups (p = 0.23). There was a negative correlation between ICV and ASPECTS scores in each occlusion group in all groups.

Conclusion

The quantitative evaluation of ICV at rCBF <20% and CBV <1 mL/100 g was negatively correlated with the ASPECTS score in GE's CT Perfusion imaging analysis software.

Association Between Time to Treatment and Outcomes of Endovascular Therapy vs Medical Management in Patients With Large Ischemic Stroke

BACKGROUND AND OBJECTIVES

Randomized trials have proven the benefit of endovascular therapy (EVT) for acute large ischemic stroke. This study was to characterize the effect of time to treatment on benefit of EVT vs medical management (MM) among patients with large ischemic stroke.

METHODS

This was a post hoc analysis of the Endovascular Therapy in Acute Anterior Circulation Large Vessel Occlusive Patients with a Large Infarct Core randomized trial. Patients who had an Alberta Stroke Program Early Computed Tomography Score of 3-5 or an ischemic core volume of 70-100 mL within 24 hours of symptom onset were treated with EVT plus MM or MM. Onset-to-expected arterial puncture time (OPT) was analyzed as a categorical variable (<6, 6-<12, and 12-24 hours) using binary logistic regression and as a continuous variable using a multivariable fractional polynomial interaction. The primary efficacy outcome was favorable outcomes (modified Rankin Scale scores 0-3) at 90 days. Safety outcomes included any intracranial hemorrhage (ICH), symptomatic ICH, and mortality.

RESULTS

Among 451 patients (median age 68 years; 61.4% were men; median OPT 487 minutes [interquartile range 328-802]), 226 patients received EVT and 225 patients received MM. The EVT group showed higher rates of favorable outcomes than the MM group within OPT of 6 hours (44.4% vs 29.9%, adjusted odds ratio [aOR] 2.78, 95% CI 1.22-6.32) and 6-12 hours (45.7% vs 29.6%, aOR 2.39 [95% CI 1.21-4.71]), but not in OPT beyond 12 hours (51.6% vs 41.4%, aOR 2.05 [95% CI 0.88-4.77]). The benefit became nonsignificant after OPT of 13 hours and 22 minutes. In 3 OPT intervals, the rates of symptomatic ICH and mortality were similar between EVT and MM although the rate of any ICH increased. However, no interaction effect was found (all p interactions >0.10).

DISCUSSION

These findings strengthen the benefit of EVT initiated within 13 hours and 22 minutes after symptom onset compared with MM alone in patients with large ischemic stroke, but EVT should not be withheld for patients presenting beyond 13 hours and 22 minutes. Pooled analysis of larger sample sizes is needed.

TRIAL REGISTRATION INFORMATION

ClinicalTrials.gov; NCT04551664.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that EVT is associated with improved functional outcomes for acute large ischemic stroke within 24 hours after last known well, with no interaction by time.

Cost-effectiveness of endovascular therapy for acute stroke with a large ischemic region in Japan: impact of the Alberta Stroke Program Early CT Score on cost-effectiveness

BACKGROUND

Although randomized clinical trials (RCTs) demonstrated short-term benefits of endovascular therapy (EVT) for acute ischemic stroke (AIS) with a large ischemic region, little is known about the long-term cost-effectiveness or its difference by the extent of the ischemic areas. We aimed to assess the cost-effectiveness of EVT for AIS involving a large ischemic region from the perspective of Japanese health insurance payers, and analyze it using the Alberta Stroke Program Early CT Score (ASPECTS).

METHODS

The Recovery by Endovascular Salvage for Cerebral Ultra-acute Embolism-Japan Large Ischemic Core Trial (RESCUE-Japan LIMIT) was a RCT enrolling AIS patients with ASPECTS of 3-5 initially determined by the treating neurologist primarily using MRI. The hypothetical cohort and treatment efficacy were derived from the RESCUE-Japan LIMIT. Costs were calculated using the national health insurance tariff. We stratified the cohort into two subgroups based on ASPECTS of ≤3 and 4-5 as determined by the imaging committee, because heterogeneity was observed in treatment efficacy. EVT was considered cost-effective if the incremental cost-effectiveness ratio (ICER) was below the willingness-to-pay of 5 000 000 Japanese yen (JPY)/quality-adjusted life year (QALY).

RESULTS

EVT was cost-effective among the RESCUE-Japan LIMIT population (ICER 4 826 911 JPY/QALY). The ICER among those with ASPECTS of ≤3 and 4-5 was 19 396 253 and 561 582 JPY/QALY, respectively.

CONCLUSION

EVT was cost-effective for patients with AIS involving a large ischemic region with ASPECTS of 3-5 initially determined by the treating neurologist in Japan. However, the ICER was over 5 000 000 JPY/QALY among those with an ASPECTS of ≤3 as determined by the imaging committee.

Discrepancies in ASPECTS obtained by artificial intelligence and experts: Associated factors and prognostic implications

PURPOSE

The differences between the Alberta Stroke Program Early CT Score (ASPECTS) obtained by experts and artificial intelligence (AI) software require elucidation. We aimed to characterize the discrepancies between the ASPECTS obtained by AI and experts and determine the associated factors and prognostic implications.

METHODS

This multicenter, retrospective, observational cohort study included patients showing acute ischemic stroke caused by large-vessel occlusion in the anterior circulation. ASPECTS was determined by AI software (RAPID ASPECTS) and experts from the core laboratory. Interclass correlation coefficients (ICCs) and Bland-Altman plots were used to illustrate the consistency and discrepancies; logistic regression analyses were used to assess the correlates of inconsistency; and receiver operating characteristic analyses were performed to assess the diagnostic performance for predicting unfavorable clinical outcomes.

RESULTS

The study population included 491 patients. The ICC for the expert and AI ASPECTS was 0.63 (95 % confidence interval [CI]: 0.25-0.79).The mean difference between expert and AI ASPECTS was 2.24. Chronic infarcts (odds ratio [OR], 1.9; 95 % CI, 1.1-3.4; P=0.021) and expert scores in the internal capsule (OR, 2.9; 95 % CI, 1.1-7.7; P=0.034) and lentiform (OR, 2.4; 95 % CI, 1.3-4.7; P=0.008) were significant correlates of inconsistency. The ASPECTS obtained by AI showed a significantly higher area under the curve for unfavorable outcomes (0.68 vs. 0.63, P=0.04).

CONCLUSIONS

In comparison with expert ASPECTS, AI ASPECTS overestimated the infarct extent. Future studies should aim to determine whether AI ASPECTS assessments should use a lower threshold to screen patients for endovascular therapy.

Near-Complete Reversal of Large Diffusion-Weighted Imaging Lesion after Thrombectomy: A Case Report and Literature Review

INTRODUCTION

Diffusion-weighted imaging (DWI) plays a crucial role in acute ischemic stroke (AIS), as it is used to evaluate the ischemic lesions that are irreversibly damaged. The reversibility of DWI ischemic lesions has been noted in patients with AIS who undergo revascularization therapy. In addition, the occurrence of this phenomenon in large ischemic regions remains rare, particularly the near-complete reversal of large DWI lesion cases.

CASE PRESENTATION

A 58-year-old male presented with a generalized tonic-clonic seizure. Emergent magnetic resonance imaging (MRI) revealed an extremely large infarction lesion in the right hemisphere with an Alberta Stroke Program Early Computed Tomographic Score (ASPECTS) value of 2 and occlusion of the terminal right internal carotid artery. The patient was immediately transferred to the Digital Subtraction Angiography (DSA) Unit for endovascular treatment with a stent retriever. After a rapid successful reperfusion with expanded treatment in cerebral infarction (eTICI) score of 3, the patient promptly recovered 24 h after the procedure. A brain MRI was repeated after 8 days of admission, and interestingly, the DWI lesion showed significant reversal. The modified Rankin scale (mRS) at discharge was 2 and 1 at 90-day follow-up, respectively.

CONCLUSIONS

Our case shows that the reversibility of DWI ischemic lesions can occur during the acute stroke phase, even in patients with extremely large regions, if rapid and successful reperfusion is achieved. The clinical implications of this phenomenon indicate that using DWI to evaluate the infarct core should be interpreted with caution.

Intravenous alteplase before endovascular therapy for acute large vessel occlusion with large ischemic core: subanalysis of a randomized clinical trial

BACKGROUND

The efficacy of endovascular therapy (EVT) in patients with large ischemic core has been reported, but it remains unclear whether IV alteplase (IVT) has beneficial effects in addition to EVT in such patients. We evaluated the efficacy and safety of EVT with or without IVT.

METHODS

The RESCUE-Japan LIMIT was an open-label, prospective, multicenter, randomized clinical trial to evaluate the efficacy and safety of EVT in stroke patients with large ischemic core, defined as Alberta Stroke Program Early CT Score (ASPECTS) 3-5. This subanalysis evaluated the differences in the effects of EVT with medical care (EVT group) compared with medical care alone (No-EVT group) between those who received IVT (IVT stratum) and those who did not (No-IVT stratum) before EVT.

RESULTS

Among 202 enrolled patients, 147 (73%) did not receive IVT. In the No-IVT stratum, the modified Rankin Scale (mRS) score of 0-3 at 90 days was significantly higher in the EVT group than in the No-EVT group (31.1% vs 12.3%, OR 3.21 (95% CI 1.37 to 7.53)). In the IVT stratum, the mRS score of 0-3 was 30.8% in the EVT group and 13.8% in the No-EVT group (OR 2.78 (95% CI 0.72 to 10.7)) (interaction p=0.77). The incidence of symptomatic intracranial hemorrhage was not different between the two groups in the No-IVT stratum (OR 1.20 (95% CI 0.35 to 4.12)), but it was significantly higher in the EVT group than in the No-EVT group in the IVT stratum (11.5% vs 0%, p=0.03).

CONCLUSIONS

There was no difference in efficacy of EVT with or without IVT, while IVT before EVT might increase symptomatic intracranial hemorrhage in patients with large ischemic core.

TRIAL REGISTRATION INFORMATION

NCT03702413.

Thrombectomy for patients with a large infarct core: a study-level meta-analysis with trial sequential analysis

Background

The effectiveness and safety of endovascular treatment compared with medical management alone regarding outcomes for patients with a large infarct core remain uncertain.

Objectives

To juxtapose the clinical outcomes of thrombectomy versus the best medical care in patients with a large infarct core.

Design

Systematic review and meta-analysis.

Data sources and methods

We conducted searches in PubMed, Cochrane, and Embase for articles published up until November 8, 2023. Randomized trials were selected for inclusion if they encompassed patients with large vessel occlusion and sizable strokes receiving thrombectomy. The primary outcome was functional outcomes at 3 months after pooling data using random-effects modeling. Safety outcomes included mortality at 3 months, symptomatic intracranial hemorrhage (SICH), and decompressive craniectomy. We performed a trial sequential analysis to balance type I and II errors.

Results

From 904 citations, we identified six randomized trials, involving a cohort of 1897 patients with a large ischemic region. Of these, 953 individuals underwent endovascular thrombectomy. At 3 months, thrombectomy was significantly correlated with better neurological prognosis, as evidenced by the increased odds of good functional outcomes (odds ratio (OR), 2.90; 95% confidence interval (CI), 2.08-4.05) and favorable functional outcomes (OR, 2.40; 95% CI, 1.86-3.09). Mortality rates did not demonstrably diminish as a consequence of the endovascular management (OR, 0.78; 95% CI, 0.58-1.06). However, the incidence of SICH was greater in the thrombectomy group compared to those with only medical treatment (5.5% vs 3.2%; OR, 1.77; 95% CI, 1.11-2.83). The application of trial sequential analysis yielded definitive evidence regarding favorable function outcomes and a shift in the distribution of modified Rankin scale scores at 3 months; however, others remained inconclusive.

Conclusion

The results from most of the included trials display consistency. Meta-analysis of these six randomized trials offers high-quality evidence that thrombectomy significantly mitigates disability in patients with a large infarction, while also increasing the risk of SICH.

Trial registration

PROSPERO, CRD42023480359.

Thrombectomy for Stroke With Large Infarct on Noncontrast CT: The TESLA Randomized Clinical Trial

Importance

Recent large infarct thrombectomy trials used heterogeneous imaging modalities and time windows for patient selection. Noncontrast computed tomographic (CT) scan is the most common stroke imaging approach. It remains uncertain whether thrombectomy is effective for patients with large infarcts identified using noncontrast CT alone within 24 hours of stroke onset.

Objective

To evaluate the effect of thrombectomy in patients with a large infarct on a noncontrast CT scan within 24 hours of onset.

Design, Setting, and Participants

Open-label, blinded-end point, bayesian-adaptive randomized trial with interim analyses for early stopping (futility or success) or population enrichment, which was conducted at 47 US academic and community-based stroke thrombectomy centers. Three hundred patients presenting within 24 hours with anterior-circulation, large-vessel occlusion and large infarct on noncontrast CT scan, with Alberta Stroke Program Early CT Scores of 2 to 5, were randomized to undergo thrombectomy or usual care. Enrollment occurred July 16, 2019 to October 17, 2022; final follow-up, January 25, 2023.

Intervention

The intervention patients (n = 152) underwent endovascular treatment using standard thrombectomy devices and usual medical care. Control patients (n = 148) underwent usual medical care alone.

Main Outcomes and Measures

The primary efficacy end point was improvement in 90-day functional outcome measured using mean utility-weighted modified Rankin Scale (UW-mRS) scores (range, 0 [death or severe disability] to 10 [no symptoms]; minimum clinically important difference, 0.3). A bayesian model determined the posterior probability that the intervention would be superior to usual care; statistical significance was a 1-sided posterior probability of .975 or more. The primary adverse event end point was 90-day mortality; secondary adverse event end points included symptomatic intracranial hemorrhage and radiographic intracranial hemorrhage.

Results

The trial enrolled 300 patients (152 intervention, 148 control; 138 females [46%]; median age, 67 years), without early stopping or enrichment; 297 patients completed the 90-day follow-up. The mean (SD) 90-day UW-mRS score was 2.93 (3.39) for the intervention group vs 2.27 (2.98) for the control group with an adjusted difference of 0.63 (95% credible interval [CrI], -0.09 to 1.34; posterior probability for superiority of thrombectomy, .96). The 90-day mortality was similar between groups: 35.3% (53 of 150) for the intervention group vs 33.3% (49 of 147) for the control group. Six of 151 patients (4.0%) in the intervention group and 2 of 149 (1.3%) in the control group experienced 24-hour symptomatic intracranial hemorrhage. Fourteen patients of 148 (9.5%) in the intervention group vs 4 of 146 (2.7%) in the control group experienced parenchymal hematoma type 1 hemorrhages; 14 (9.5%) in the intervention group vs 5 (3.4%) in the control group experienced parenchymal hematoma type 2 hemorrhages; and 24 (16.2%) in the intervention group vs 9 (6.2%) in the control group experienced subarachnoid hemorrhages.

Conclusions and Relevance

Among patients with a large infarct on noncontrast CT within 24 hours, thrombectomy did not demonstrate improvement in functional outcomes. But the width of the credible interval around the effect estimate includes the possibility of both no important effect and a clinically relevant benefit, so the potential role of thrombectomy with this imaging approach and time window will likely require additional study.

Trial Registration

ClinicalTrials.gov Identifier: NCT03805308.

Endovascular treatment versus standard medical treatment in patients with established large infarct: a cohort study

BACKGROUND

Previous trials confirmed the benefit of endovascular treatment (EVT) in acute large core stroke, but the effect of EVT on outcomes in these patients based on noncontrast computed tomography (NCCT) in real-world clinical practice was unclear. The aim of this study was to explore the effect of EVT versus standard medical treatment (SMT) in patients with large ischemic core stroke defined as Alberta Stroke Program Early CT Score (ASPECTS) ≤5 based on NCCT alone.

MATERIALS AND METHODS

Patients with acute large core stroke at 38 Chinese centers between November 2021 and February 2023 were reviewed from a prospectively maintained database. The primary outcome was favorable functional outcome [modified Rankin Scale score (mRS), 0-3] at 90 days. Safety outcomes included 48 h symptomatic intracerebral hemorrhage (sICH) and 90-day mortality.

RESULTS

Of 745 eligible patients recruited at 38 stroke centers between November 2021 and February 2023, 490 were treated with EVT+SMT and 255 with SMT alone. One hundred and eighty-one (36.9%) in the EVT group achieved favorable functional independence versus 48 (18.8%) treated with SMT only [adjusted risk ratio (RR), 1.86; 95% CI: 1.43-2.42, P <0.001; adjusted risk difference (RD), 13.77; 95% CI: 7.40-20.15, P <0.001]. The proportion of sICH was significantly higher in patients undergoing EVT (13.3 vs. 2.4%; adjusted RR, 5.17; 95% CI: 2.17-12.32, P <0.001; adjusted RD, 10.10; 95% CI: 6.12-14.09, P <0.001). No significant difference of mortality between the groups was observed (41.8 vs. 49.0%; adjusted RR, 0.91; 95% CI: 0.77-1.07, P =0.24; adjusted RD, -5.91; 95% CI: -12.91-1.09, P =0.1).

CONCLUSION

Among patients with acute large core stroke based on NCCT in real-world, EVT is associated with better functional outcomes at 90 days despite of higher risk of sICH. Rates of procedure-related complications were relatively higher in the EVT+SMT group.

Functional Outcome and Hemorrhage Rates After Bridging Therapy With Tenecteplase or Alteplase in Patients With Large Ischemic Core

BACKGROUND AND OBJECTIVES

IV tenecteplase is an alternative to alteplase before mechanical thrombectomy (MT) in patients with large-vessel occlusion (LVO) ischemic stroke. Little data are available on its use in patients with large ischemic core. We aimed to compare the efficacy and safety of both thrombolytics in this population.

METHODS

We conducted a retrospective analysis of patients with anterior circulation LVO strokes and diffusion-weighed imaging Alberta Stroke Program Early CT Score (DWI-ASPECTS) ≤5 treated with tenecteplase or alteplase before MT from the TETRIS (tenecteplase) and ETIS (alteplase) French multicenter registries. Primary outcome was reduced disability at 3 months (ordinal analysis of the modified Rankin scale [mRS]). Safety outcomes were 3-month mortality, parenchymal hematoma (PH), and symptomatic intracranial hemorrhage (sICH). We used propensity score overlap weighting to reduce baseline differences between treatment groups.

RESULTS

We analyzed 647 patients (tenecteplase: n = 194; alteplase: n = 453; inclusion period 2015-2022). Median (interquartile range) age was 71 (57-81) years, with NIH Stroke Scale score 19 (16-22), DWI-ASPECTS 4 (3-5), and last seen well-to-IV thrombolysis and puncture times 165 minutes (130-226) and 260 minutes (203-349), respectively. After MT, the successful reperfusion rate was 83.1%. After propensity score overlap weighting, all baseline variables were well balanced between both treatment groups. Compared with patients treated with alteplase, patients treated with tenecteplase had better 3-month mRS (common odds ratio [OR] for reduced disability: 1.37, 1.01-1.87, p = 0.046) and lower 3-month mortality (OR 0.52, 0.33-0.81, p < 0.01). There were no significant differences between thrombolytics for PH (OR 0.84, 0.55-1.30, p = 0.44) and sICH incidence (OR 0.70, 0.42-1.18, p = 0.18).

DISCUSSION

Our data are encouraging regarding the efficacy and reassuring regarding the safety of tenecteplase compared with that of alteplase in bridging therapy for patients with LVO strokes and a large ischemic core in routine clinical care. These results support its consideration as an alternative to alteplase in bridging therapy for patients with large ischemic cores.

TRIALS REGISTRATION INFORMATION

NCT03776877 (ETIS registry) and NCT05534360 (TETRIS registry).

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that patients with anterior circulation LVO stroke and DWI-ASPECTS ≤5 treated with tenecteplase vs alteplase before MT experienced better functional outcomes and lower mortality at 3 months.

Endovascular Therapy and Outcomes Among Patients With Very Large Ischemic Core Stroke

Importance

The association of endovascular therapy (EVT) with outcomes is unclear for patients with very low Alberta Stroke Program Early Computed Tomography Score (ASPECTS) within 24 hours of stroke onset.

Objective

To explore the association of EVT with functional and safety outcomes among patients with ASPECTS of 0 to 2 scored with noncontrast computed tomography.

Design, Setting, and Participants

This cohort study used data from an ongoing, prospective, observational, nationwide registry including all patients treated at 38 stroke centers in China with an occlusion in the internal carotid artery or M1 or M2 segment of the middle cerebral artery within 24 hours of witnessed symptom onset. Patients with ASPECTS of 0 to 2 between November 1, 2021, and February 8, 2023, were included in analysis. Data were analyzed October to November 2023.

Exposures

EVT vs standard medical treatment (SMT).

Main Outcomes and Measures

The primary outcome was favorable functional outcome, defined as modified Rankin Scale score (mRS) of 0 to 3, at 90 days. Safety outcomes included symptomatic intracerebral hemorrhage (sICH) within 48 hours and mortality at 90 days.

Results

A total of 245 patients (median [IQR] age, 71 [63-78] years; 118 [48%] women) with ASPECTS of 0 to 2 were included, of whom 111 patients (45.1%) received SMT and 135 patients (54.9%) received EVT. The EVT group had significantly greater odds of favorable functional outcome at 90 days than the SMT group (30 patients [22.2%] vs 11 patients [9.9%]; P = .01; adjusted odds ratio [aOR], 3.07 [95% CI, 1.29-7.31]; P = .01). Patients in the EVT group, compared with the SMT group, had significantly greater odds of any ICH (56 patients [41.5%] vs 16 patients [11.4%]; P < .001; aOR, 4.27 [95% CI, 2.19-8.35]; P < .001) and sICH (24 patients [17.8%] vs 1 patient [0.9%]; P < .001; aOR, 23.07 [95% CI, 2.99-177.79]; P = .003) within 48 hours. There were no differences between groups for 90-day mortality (80 patients [59.3%] vs 59 patients [53.2%]; P = .34; aOR, 1.38 [95% CI, 0.77-2.47]; P = .28). The results remained robust in the propensity score-matched analysis.

Conclusions and Relevance

In this cohort study of patients with very low ASPECTS based on NCCT within 24 hours of stroke onset, those treated with EVT had higher odds of a favorable functional outcome compared with those who received SMT. Randomized clinical trials are needed to assess these findings.

Application of imaging modalities for endovascular thrombectomy of large core infarcts in clinical practice

Four randomized controlled trials of large infarct core volume (LICV) included three imaging modalities: non-contrast CT (NCCT)-Alberta Stroke Program Early CT Score (ASPECTS), diffusion-weighted imaging (DWI)-ASPECTS, and NCCT-ASPECTS combined with CTP (CT perfusion). However, there is no clear consensus on the optimal imaging modality for endovascular thrombectomy (EVT) trials of large core infarcts. The variety and complexity of imaging modalities make it difficult to apply them in clinical practice. By familiarizing ourselves with these imaging modalities, we can better apply them in the clinic and correctly screen patients with large core infarcts in the anterior circulation who can benefit from EVT therapy.

MRI of cerebral oedema in ischaemic stroke and its current use in routine clinical practice

Currently, with the knowledge of the role of collateral circulation in the development of cerebral ischaemia, traditional therapeutic windows are being prolonged, with time not being the only criterion. Instead, a more personalised approach is applied to select additional patients who might benefit from active treatment. This review briefly describes the current knowledge of the pathophysiology of the development of early ischaemic changes, the capabilities of MRI to depict such changes, and the basics of the routinely used imaging techniques broadly available for the assessment of individual phases of cerebral ischaemia, and summarises the possible clinical use of routine MR imaging, including patient selection for active treatment and assessment of the outcome on the basis of imaging.

MRI vs CT for Baseline Imaging Evaluation in Acute Large Artery Ischemic Stroke: A Subanalysis of the SWIFT-DIRECT Trial

BACKGROUND AND OBJECTIVES

Whether MRI or CT is preferable for the evaluation of patients with suspected stroke remains a matter of debate, given that the imaging modality acquired at baseline may be a relevant determinant of workflow delays and outcomes with it, in patients with stroke undergoing acute reperfusion therapies.

METHODS

In this post hoc analysis of the SWIFT-DIRECT trial that investigated noninferiority of thrombectomy alone vs IV thrombolysis (IVT) + thrombectomy in patients with an acute ischemic anterior circulation large vessel occlusive stroke eligible to receive IVT within 4.5 hours after last seen well, we tested for a potential interaction between baseline imaging modality (MRI/MR-angiography [MRA] vs CT/CT-angiography [CTA]) and the effect of acute treatment (thrombectomy vs IVT + thrombectomy) on clinical and safety outcomes and procedural metrics (primary analysis). Moreover, we examined the association between baseline imaging modality and these outcomes using regression models adjusted for age, sex, baseline NIH Stroke Scale (NIHSS), occlusion location, and Alberta Stroke Program Early CT Score (ASPECTS) (secondary analysis). Endpoints included workflow times, the modified Rankin scale (mRS) score at 90 days, the rate of successful reperfusion, the odds for early neurologic deterioration within 24 hours, and the risk of symptomatic intracranial hemorrhage. The imaging modality acquired was chosen at the discretion of the treating physicians and commonly reflects center-specific standard procedures.

RESULTS

Four hundred five of 408 patients enrolled in the SWIFT-DIRECT trial were included in this substudy. Two hundred (49.4%) patients underwent MRI/MRA, and 205 (50.6%) underwent CT/CTA. Patients with MRI/MRA had lower NIHSS scores (16 [interquartile range (IQR) 12-20] vs 18 [IQR 14-20], p = 0.012) and lower ASPECTS (8 [IQR 6-9] vs 8 [IQR 7-9], p = 0.021) compared with those with CT/CTA. In terms of the primary analysis, we found no evidence for an interaction between baseline imaging modality and the effect of IVT + thrombectomy vs thrombectomy alone. Regarding the secondary analysis, MRI/MRA acquisition was associated with workflow delays of approximately 20 minutes, higher odds of functional independence at 90 days (adjusted odds ratio [aOR] 1.65, 95% CI 1.07-2.56), and similar mortality rates (aOR 0.73, 95% CI 0.36-1.47) compared with CT/CTA.

DISCUSSION

This post hoc analysis does not suggest treatment effect heterogeneity of IVT + thrombectomy vs thrombectomy alone in large artery stroke patients with different imaging modalities. There was no evidence that functional outcome at 90 days was less favorable following MRI/MRA at baseline compared with CT/CTA, despite significant workflow delays.

TRIAL REGISTRATION INFORMATION

ClinicalTrials.gov Identifier: NCT03192332.

Interaction between intravenous thrombolysis and clinical outcome between slow and fast progressors undergoing mechanical thrombectomy: a post-hoc analysis of the SWIFT-DIRECT trial

BACKGROUND

In proximal occlusions, the effect of reperfusion therapies may differ between slow or fast progressors. We investigated the effect of intravenous thrombolysis (IVT) (with alteplase) plus mechanical thrombectomy (MT) versus thrombectomy alone among slow versus fast stroke progressors.

METHODS

The SWIFT-DIRECT trial data were analyzed: 408 patients randomized to IVT+MT or MT alone. Infarct growth speed was defined by the number of points of decay in the initial Alberta Stroke Program Early CT Score (ASPECTS) divided by the onset-to-imaging time. The primary endpoint was 3-month functional independence (modified Rankin scale 0-2). In the primary analysis, the study population was dichotomized into slow and fast progressors using median infarct growth velocity. Secondary analysis was also conducted using quartiles of ASPECTS decay.

RESULTS

We included 376 patients: 191 IVT+MT, 185 MT alone; median age 73 years (IQR 65-81); median initial National Institutes of Health Stroke Scale (NIHSS) 17 (IQR 13-20). The median infarct growth velocity was 1.2 points/hour. Overall, we did not observe a significant interaction between the infarct growth speed and the allocation to either randomization group on the odds of favourable outcome (P=0.68). In the IVT+MT group, odds of any intracranial hemorrhage (ICH) were significantly lower in slow progressors (22.8% vs 36.4%; OR 0.52, 95% CI 0.27 to 0.98) and higher among fast progressors (49.4% vs 26.8%; OR 2.62, 95% CI 1.42 to 4.82) (P value for interaction <0.001). Similar results were observed in secondary analyses.

CONCLUSION

In this SWIFT-DIRECT subanalysis, we did not find evidence for a significant interaction of the velocity of infarct growth on the odds of favourable outcome according to treatment by MT alone or combined IVT+MT. However, prior IVT was associated with significantly reduced occurrence of any ICH among slow progressors whereas this was increased in fast progressors.

Revolutionizing the Management of Large-Core Ischaemic Strokes: Decoding the Success of Endovascular Therapy in the Recent Stroke Trials

Endovascular therapy (EVT) has revolutionized the management of acute ischaemic strokes with large vessel occlusion, with emerging evidence suggesting its benefit also in large infarct core volume strokes. In the last two years, four randomised controlled trials have been published on this topic-RESCUE-Japan LIMIT, ANGEL-ASPECT, SELECT2 and TENSION, with overall results showing that EVT improves functional and neurological outcomes compared to medical management alone. This review aims to summarise the recent evidence presented by these four trials and highlight some of the limitations in our current understanding of this topic.

A differential detailed diffusion-weighted imaging-ASPECTS for cerebral infarct volume measurement and outcome prediction

BACKGROUND

Diffusion-weighted imaging-Alberta Stroke Program Early Computed Tomography Score (DWI-ASPECTS) has been used to estimate infarct core volume in acute stroke. However, the same and indiscriminate score deduction for punctate or confluent DWI high-intensity lesion might lead to variation in performance.

AIMS

To develop and evaluate a differential detailed DWI-ASPECTS method in comparison with the conventional DWI-ASPECTS in core infarct volume measurement and clinical outcome prediction.

METHODS

We retrospectively recruited patients with acute ischemic stroke (AIS) treated with endovascular treatment between April 2013 and October 2019. In differential detailed DWI-ASPECTS, restricted diffusion lesion that was punctate or less than half of a cortical region (M1-M6) would not lead to subtraction of point. A favorable outcome was modified Rankin Scale score ⩽2 at 90 days after stroke onset.

RESULTS

Among 298 AIS patients, mean age was 75 years (interquartile range (IQR) 67-82), and 194 patients (65%) were males. Mean infarct core volume was 11 mL (IQR 3-37). Overall, the score by detailed DWI-ASPECTS was significantly higher than conventional DWI-ASPECTS (8 (7-9) vs. 7 (5-9); P < 0.01). The detailed DWI-ASPECTS resulted in a higher correlation coefficient (r) for core infarct volume estimation than the conventional DWI-ASPECTS (r = 0.832 vs. 0.773; P < 0.01). Upon re-classification of those scored ⩽6 in conventional DWI-ASPECTS (n = 134) by detailed DWI-ASPECTS, the rate of favorable outcome in patients with detailed DWI-ASPECTS >6 was significantly higher than those with ⩽6 (29 (48%) vs. 14 (19%); P < 0.01).

CONCLUSIONS

Detailed DWI-ASPECTS appeared to provide a more accurate infarct core volume measurement and clinical outcome correlation than conventional DWI-ASPECTS among AIS patients treated with endovascular therapy.

Relevance of National Institutes of Health Stroke Scale subitems for best revascularization therapy in minor stroke patients with large vessel occlusion: An observational multicentric study

BACKGROUND AND PURPOSE

The best management of acute ischemic stroke patients with a minor stroke and large vessel occlusion is still uncertain. Specific clinical and radiological data may help to select patients who would benefit from endovascular therapy (EVT). We aimed to evaluate the relevance of National Institutes of Health Stroke Scale (NIHSS) subitems for predicting the potential benefit of providing EVT after intravenous thrombolysis (IVT; "bridging treatment") versus IVT alone.

METHODS

We extracted demographic, clinical, risk factor, radiological, revascularization and outcome data of consecutive patients with M1 or proximal M2 middle cerebral artery occlusion and admission NIHSS scores of 0-5 points, treated with IVT ± EVT between May 2005 and March 2021, from nine prospectively constructed stroke registries at seven French and two Swiss comprehensive stroke centers. Adjusted interaction analyses were performed between admission NIHSS subitems and revascularization modality for two primary outcomes at 3 months: non-excellent functional outcome (modified Rankin Scale score 2-6) and difference in NIHSS score between 3 months and admission.

RESULTS

Of the 533 patients included (median age 68.2 years, 46% women, median admission NIHSS score 3), 136 (25.5%) initially received bridging therapy and 397 (74.5%) received IVT alone. Adjusted interaction analysis revealed that only facial palsy on admission was more frequently associated with excellent outcome in patients treated by IVT alone versus bridging therapy (odds ratio 0.47, 95% confidence interval 0.24-0.91; p = 0.013). Regarding NIHSS difference at 3 months, no single NIHSS subitem interacted with type of revascularization.

CONCLUSIONS

This retrospective multicenter analysis found that NIHSS subitems at admission had little value in predicting patients who might benefit from bridging therapy as opposed to IVT alone. Further research is needed to identify better markers for selecting EVT responders with minor strokes.

Priorities for Advancements in Neuroimaging in the Diagnostic Workup of Acute Stroke

STAIR XII (12th Stroke Treatment Academy Industry Roundtable) included a workshop to discuss the priorities for advancements in neuroimaging in the diagnostic workup of acute ischemic stroke. The workshop brought together representatives from academia, industry, and government. The participants identified 10 critical areas of priority for the advancement of acute stroke imaging. These include enhancing imaging capabilities at primary and comprehensive stroke centers, refining the analysis and characterization of clots, establishing imaging criteria that can predict the response to reperfusion, optimizing the Thrombolysis in Cerebral Infarction scale, predicting first-pass reperfusion outcomes, improving imaging techniques post-reperfusion therapy, detecting early ischemia on noncontrast computed tomography, enhancing cone beam computed tomography, advancing mobile stroke units, and leveraging high-resolution vessel wall imaging to gain deeper insights into pathology. Imaging in acute ischemic stroke treatment has advanced significantly, but important challenges remain that need to be addressed. A combined effort from academic investigators, industry, and regulators is needed to improve imaging technologies and, ultimately, patient outcomes.

Current and future trends in acute ischemic stroke treatment: direct-to-angiography suite, middle vessel occlusion, large core, and minor strokes

Since the publication of the landmark thrombectomy trials in 2015, the field of endovascular therapy for ischemic stroke has been rapidly growing. The very low number needed to treat to provide functional benefits shown by the initial randomized trials has led clinicians and investigators to seek to translate the benefits of endovascular therapy to other patient subgroups. Even if the treatment effect is diminished, currently available data has provided sufficient information to extend endovascular therapy to large infarct core patients. Recently, published data have also shown that sophisticated imaging is not necessary for late time- window patients. As a result, further research into patient selection and the stroke pathway now focuses on dramatically reducing door-to-groin times and improving outcomes by circumventing classical imaging paradigms altogether and employing a direct-to-angio suite approach for selected large vessel occlusion patients in the early time window. While the results of this approach mainly concern patients with severe deficits, there are further struggles to provide evidence of the efficacy and safety of endovascular treatment in minor stroke and large vessel occlusion, as well as in patients with middle vessel occlusions. The current lack of good quality data regarding these patients provides significant challenges for accurately selecting potential candidates for endovascular treatment. However, current and future randomized trials will probably elucidate the efficacy of endovascular treatment in these patient populations.

Endovascular Thrombectomy in Patients With Very Low ASPECTS Scores: A Systematic Review and Meta-analysis

OBJECTIVES

Randomized controlled trials (RCTs) have recently established the benefit of endovascular thrombectomy (EVT) in patients with large infarct core on baseline neuroimaging. We evaluated the utility of EVT in patients with very large infarct core, defined as Alberta Stroke Program Early CT scores (ASPECTS) of less than 3.

METHODS

We performed a systematic review and meta-analysis of the subgroups of patients with baseline ASPECTS scores 0-2 included in RCTs evaluating the utility of EVT in the setting of a large infarct core. The outcome of interest was the probability of three-month functional improvement assessed with the generalized odds ratios (ORs) of the modified Rankin Scale (mRS) scores between patients receiving EVT and medical management.

RESULTS

In the pooled analyses of 82 participants of the total 808 (10%) enrolled in 2 individual trials, we found a statistically significant shift in the distribution of mRS scores toward better outcomes in favor of EVT (generalized OR 1.46, 95% CI 1.03-2.07). No evidence of heterogeneity was detected (I 2 = 0%; p for Cochran Q = 0.73).

DISCUSSION

The results from our pooled analysis challenge the exclusion of patients presenting with ASPECTS scores less than 3 from receiving EVT if they are otherwise eligible.

Endovascular therapy versus medical management for acute ischemic stroke with large infarct core: Systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

To compare the efficacy and safety of endovascular therapy (EVT) versus best medical management (BMM) in patients with acute ischemic stroke (AIS) with large infarct core.

METHODS

We searched Pubmed, Embase and Cochrane Central Register of Controlled Trials for published randomized clinical trials (RCTs) from inception to February 18, 2023. We defined patients with large core infarcts as having an Alberta Stroke Program early computed tomography score (ASPECTS) of 3-5. The primary outcome was functional independence, defined as a score of 0-2 on the modified Rankin scale (mRS) at 90 days. Secondary outcome was independent ambulation defined as mRS 0-3 at 90 days. Safety outcomes were mortality at 90 days, symptomatic intracranial hemorrhage (sICH) and any intracranial hemorrhage (ICH).

RESULTS

The overall treatment effect was more favourable to EVT group. EVT was significantly correlated with improvement of functional independence at 90 days (mRS 0-2) (RR = 2.40; 95 % CI, 1.82-3.16; P < 0.01; I2 = 0 %) and independent ambulation (mRS 0-3) (RR = 1,78; 95 % CI, 1.28-2.48; P < 0.01; I2 = 58 %) at 90 days. 90-day mortality was not significantly different between the two groups(RR = 0.95; 95 % CI, 0.78-1.16; P > 0.05; I2 = 0 %). The risk of sICH and any ICH was higher in EVT group than in BMM group.

CONCLUSION

Compared with BMM, EVT may improve functional outcomes in patients with ASPECTS 3-5, despite being associated with an increased risk of sICH and any ICH.

Mode of Imaging Study and Endovascular Therapy for a Large Ischemic Core: Insights From the RESCUE-Japan LIMIT

BACKGROUND AND PURPOSE

Differences in measurement of the extent of acute ischemic stroke using the Alberta Stroke Program Early Computed Tomographic Score (ASPECTS) by non-contrast computed tomography (CT-ASPECTS stratum) and diffusion-weighted imaging (DWI-ASPECTS stratum) may impact the efficacy of endovascular therapy (EVT) in patients with a large ischemic core.

METHODS

The RESCUE-Japan LIMIT (Recovery by Endovascular Salvage for Cerebral Ultra-acute Embolism Japan-Large IscheMIc core Trial) was a multicenter, open-label, randomized clinical trial that evaluated the efficacy and safety of EVT in patients with ASPECTS of 3-5. CT-ASPECTS was prioritized when both CT-ASPECTS and DWI-ASPECTS were measured. The effects of EVT on the modified Rankin Scale (mRS) score at 90 days were assessed separately for each stratum.

RESULTS

Among 183 patients, 112 (EVT group, 53; No-EVT group, 59) were in the CT-ASPECTS stratum and 71 (EVT group, 40; No-EVT group, 31) in the DWI-ASPECTS stratum. The common odds ratio (OR) (95% confidence interval) of the EVT group for one scale shift of the mRS score toward 0 was 1.29 (0.65-2.54) compared to the No-EVT group in CT-ASPECTS stratum, and 6.15 (2.46-16.3) in DWI-ASPECTS stratum with significant interaction between treatment assignment and mode of imaging study (P=0.002). There were significant interactions in the improvement of the National Institutes of Health Stroke Scale score at 48 hours (CT-ASPECTS stratum: OR, 1.95; DWIASPECTS stratum: OR, 14.5; interaction P=0.035) and mortality at 90 days (CT-ASPECTS stratum: OR, 2.07; DWI-ASPECTS stratum: OR, 0.23; interaction P=0.008).

CONCLUSION

Patients with ASPECTS of 3-5 on MRI benefitted more from EVT than those with ASPECTS of 3-5 on CT.

Minimal Imaging Requirements

The minimal requirements for imaging studies prior to endovascular treatment (EVT) of acute ischemic stroke are those that can provide the information necessary to determine the indication for treatment (treatment triage) and procedural strategies without being time-consuming. An important notion is to determine whether the patient can benefit from EVT. We should recognize that the perfect diagnostic imaging technique does not yet exist, and each has advantages and disadvantages. Generally, stroke imaging protocols to triage for EVT include the following three options: 1) non-contrast CT and CTA, 2) CT perfusion and CTA, and 3) MRI and MRA. It is not known if perfusion imaging or MRI is mandatory for patients with stroke presenting within 6 hours of onset, although non-contrast CT alone has less power to obtain the necessary information. Dual-energy CT can distinguish between post-EVT hemorrhage and contrast agent leakage immediately after EVT.

Mechanical thrombectomy in low Alberta Stroke Program Early Computed Tomographic Score: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Due to their poor natural history and lack in level-I evidence, patients with large vessel occlusion and large core infarcts (Alberta Stroke Program Early Computed Tomographic Score <6) have been excluded from receiving mechanical thrombectomy. This systematic review and meta-analysis seeks to summarize current evidence from published randomized controlled trials to compare the safety and efficacy of mechanical thrombectomy with optimal medical therapy in treating stroke patients with large core infarcts.

METHODS

We searched PubMed and EMBASE for randomized controlled trials investigating the safety and efficacy of mechanical thrombectomy vs optimal medical therapy in patients presenting with large vessel occlusion and large infarcts. Basic demographic and comorbidities were assessed, and clinical outcomes were compared, including modified Rankin scale 0-3, and 0-2 at 3 months, symptomatic intracranial hemorrhage, decompressive hemicortectomy, and 90-day mortality.

RESULTS

Three randomized controlled trials totaling 1011 patients (501 and 510 in the medical management and mechanical thrombectomy arm, respectively) were included. Patients undergoing mechanical thrombectomy had significantly higher odds of achieving better functional outcomes at 3 months: Modified Rankin scale 0-2 (OR = 3.05, 95% CI = 2.101-4.4021, p < 0.0001) and modified Rankin scale 0-3 (OR = 2.20, 95% CI = 1.67-2.89, p < 0.0001) as compared to those receiving optimal medical management. There were no differences between groups in 90-day mortality (OR = 0.93, 95% CI = 0.70-1.23, p = 0.60), symptomatic intracranial hemorrhage (OR = 1.89, 95% = CI 0.95-3.77, p = 0.07) or decompressive hemicraniectomy (OR = 1.25, 95% CI = 0.69-2.25, p = 0.46).

CONCLUSION

Mechanical thrombectomy for patients with large infarcts is associated with improved functional outcomes and a similar safety profile compared to optimal medical management. Ongoing trials will help better refine the target population that benefits the most from treatment.

Nomogram to predict unfavorable outcome of endovascular thrombectomy for large ischemic core

OBJECTIVE

The prognosis for patients presenting with a large ischemic core (LIC) following endovascular thrombectomy is relatively poor. This study aimed to construct and validate a nomogram for predicting 3-month unfavorable outcome in patients with anterior circulation occlusion-related LIC who underwent endovascular thrombectomy.

METHODS

A retrospective training cohort and a prospective validation cohort of patients with a large ischemic core were studied. The diffusion weighted imaging related radiomic features and pre-thrombectomy clinical features were collected. After the selection of relevant features, a nomogram predicting modified Rankin Scale score of 3-6 as an unfavorable outcome was established. The discriminatory value of the nomogram was evaluated with a receiver operating characteristic curve.

RESULTS

A total of 140 patients (mean age 66.3 ± 13.4 years, 35% female) were included in this study, consisting of a training cohort (n = 95) and a validation cohort (n = 45). The percentage of patients with an mRS scores of 0-2 was 30%, 0-3 was 40.7%, and 32.9% were dead. Age, National Institute of Health Stroke Scale (NIHSS) score, and two radiomic features, Maximum2DDiameterColumn and Maximum2DDiameterSlice, were identified as factors associated with unfavorable outcome in the nomogram. The nomogram demonstrated an area under the curve of 0.892 (95% confidence interval [CI], 0.812-0.947) in the training dataset and 0.872 (95% CI, 0.739-0.953) in the validation dataset.

INTERPRETATION

This nomogram, which includes age, NIHSS score, Maximum2DDiameterColumn, and Maximum2DDiameterSlice, may predict the risk of unfavorable outcome in patients with LIC caused by anterior circulation occlusion.

Is improved access to magnetic resonance imaging imperative for optimal ischemic stroke care?

Neuroimaging, including CT and MRI, is integral to ischemic stroke (IS) treatment, management, and prevention. However, the use of MRI for IS patients is limited despite its potential to provide high-quality images that yield definitive information related to the management of IS. MRI is beneficial when the information provided by CT is insufficient for decisions related to the diagnosis, etiology, or treatment of IS. In the emergency setting, MRI can improve the diagnostic accuracy of CT-negative acute ischemic strokes (AIS) and ensure a better selection of patients for reperfusion therapies with thrombolysis and/or thrombectomy. Moreover, MR imaging may help avoid hospital admissions for patients with stroke mimics, facilitate earlier discharge, and reduce overall hospital costs. MRI in the in-patient setting can help determine stroke etiology to aid in stroke prevention management upon discharge. Furthermore, early access to MRI in IS out-patients can aid in diagnosing, risk stratifying, and determining optimal management strategies for patients with a TIA or a minor stroke. Recent technological advances, particularly low-to-mid-field MR scanners, can improve access to MRI. These MR scanners provide faster protocols, cost-effectiveness, smaller footprints, safety, and lower power requirements. In conclusion, MRI use for IS treatment, management, and prevention is imperative and justifiable, and the latest technological advancements in MR scanners hold the potential to enhance access.

Neurological Functional Independence After Endovascular Thrombectomy and Different Imaging Modalities for Large Infarct Core Assessment : A Systematic Review and Meta-analysis

PURPOSE

To investigate the rate of neurological functional independence (NFI) at 90 days in patients with large infarct core (LIC), which was evaluated by different imaging modalities before endovascular thrombectomy (EVT).

METHODS

PubMed and EMBASE were searched for original studies on clinical functional outcomes at 90 days in LIC patients who received EVT treatment from inception to 28 September 2021. The pooled NFI rates were calculated using random effects model according to different imaging modalities and criteria.

RESULTS

We included 34 studies enrolling 2997 LIC patients. The NFI rates were 23% (95% confidence interval, CI 15-32%) and 24% (95% CI 10-38%) when LIC was defined as core volume ≥50 ml and ≥ 70 ml separately on computed tomography perfusion, 36% (95% CI 23-48%) and 21% (95% CI 17-25%) when LIC was defined as core volume ≥ 50 ml and ≥ 70 ml separately on magnetic resonance diffusion-weighted imaging (DWI), 28% (95% CI 24-32%) and 37% (95% CI 21-53%) when LIC was defined as DWI-ASPECTS ≤ 5 and ≤ 6 separately, 23% (95% CI 19-27%) and 32% (95% CI 18-46%) when LIC was defined as NCCT-ASPECTS ≤ 5 and ≤ 6 separately.

CONCLUSION

Similar NFI rates could be obtained after EVT in LIC patients if proper LIC criteria were select according to the imaging modality.

Association Between Alberta Stroke Program Early Computed Tomography Score and Efficacy and Safety Outcomes With Endovascular Therapy in Patients With Stroke From Large-Vessel Occlusion: A Secondary Analysis of the Recovery by Endovascular Salvage for Cerebral Ultra-acute Embolism-Japan Large Ischemic Core Trial (RESCUE-Japan LIMIT)

Importance

Endovascular therapy (EVT) has been found to reduce functional disability in patients with acute stroke due to large-vessel occlusion. However, the extent of the ischemic region, measured using Alberta Stroke Program Early Computed Tomography Scores, may limit the efficacy of EVT.

Objective

To compare the efficacy and safety of EVT according to ASPECTS 3 or less vs 4 to 5.

Design, Setting, and Participants

The Recovery by Endovascular Salvage for Cerebral Ultra-acute Embolism-Japan Large Ischemic Core Trial (RESCUE-Japan LIMIT) was an open-label randomized clinical trial conducted from November 2018 to December 2021 at 45 stroke centers across Japan. The trial enrolled adult patients with acute ischemic stroke with a large ischemic region, defined as ASPECTS 3 to 5 primarily determined by magnetic resonance imaging, with occlusion site at the internal carotid artery or middle cerebral artery segment 1. Among 203 enrolled patients, 1 withdrew consent and 202 were included in the original trial and secondary analysis. This secondary analysis was conducted in April 2022.

Interventions

Patients were randomly assigned to EVT with medical therapy or medical therapy alone.

Main Outcomes and Measures

Modified Rankin Scale (mRS) score at 90 days and symptomatic and any intracranial hemorrhage within 48 hours.

Results

Among 202 patients, 106 (52%) had ASPECTS 3 or less (mean [SD] age, 76.7 [9.6] years; 54 female individuals [50.9%]) and 96 had ASPECTS 4 to 5 (mean [SD] age, 75.6 [10.6] years; 36 female individuals [37.5%]). Of patients with ASPECTS 3 or less, 12 (21.4%) in the EVT group and 9 (18.0%) in the no EVT group had an mRS score of 0 to 3 (odds ratio [OR], 1.24; 95% CI, 0.47-3.26). Of patients with ASPECTS 4 to 5, 19 patients (43.2%) in the EVT group and 4 (7.7%) in the no EVT group had an mRS score of 0 to 3 at 90 days (OR, 9.12; 95% CI, 2.80-29.70; interaction P = .01). The ordinal shift across the range of mRS scores toward a better outcome was not significant in those with ASPECTS or 3 or less (common OR, 1.56; 95% CI, 0.79-3.10) but was significant in those with ASPECTS 4 to 5 (common OR, 4.48; 95% CI, 2.07-9.71; interaction P = .046). The risk of intracranial hemorrhage was significantly increased in patients with ASPECTS 3 or less when EVT was conducted (OR, 4.14; 95% CI, 1.84-9.32) and nonsignificantly increased in those with ASPECTS 4 to 5 (OR, 2.05; 95% CI, 0.89-4.73; interaction P = .24).

Conclusions and Relevance

In this study, EVT was associated with improved 90-day functional outcomes in patients with acute large vessel occlusive stroke and ASPECTS was 4 to 5 but not in those with ASPECTS 3 or less.

Trial Registration

ClinicalTrials.gov Identifier: NCT03702413.

Endovascular treatment for anterior circulation large-vessel occlusion ischemic stroke with low ASPECTS: a systematic review and meta-analysis

BACKGROUND

Endovascular treatment (EVT) for acute ischemic stroke (AIS) patients presenting with Alberta Stroke Program Early CT Score (ASPECTS) 0-5 has not yet proven safe and effective by clinical trials.

OBJECTIVES

The aim of the study was to assess whether EVT in AIS patients presenting with low ASPECTS is beneficial.

DESIGN

Systematic review and meta-analysis of available studies in accordance with the PRISMA statement.

DATA SOURCES AND METHODS

We have searched MEDLINE, the Cochrane Central Register of Controlled Trials, and reference lists of articles published until 28 May 2022 with the aim to calculate (1) modified Rankin scale (mRS) score 0-3 at 3 months, (2) mRS score 0-2 at 3 months, (3) symptomatic intracranial hemorrhage (sICH), and (3) mortality at 3 months.

RESULTS

Overall, 24 eligible studies were included in the meta-analysis, comprising a total of 2539 AIS patients with ASPECTS 0-5 treated with EVT. The pooled proportion of EVT-treated patients achieving mRS 0-3 at 3 months was calculated at 38.4%. The pooled proportion of EVT-treated patients achieving mRS 0-2 at 3 months was 25.7%. Regarding safety outcomes, sICH occurred in 12.8% of patients. The 3-month pooled mortality was 30%. In pairwise meta-analysis, patients treated with EVT had a higher likelihood of achieving mRS 0-3 at 3 months compared with patients treated with best medical therapy (BMT, OR: 2.41). sICH occurred more frequently in EVT-treated patients compared with the BMT-treated patients (OR: 2.30). Mortality at 3 months was not different between the two treatment groups (OR: 0.71).

CONCLUSION

EVT may be beneficial for AIS patients with low baseline ASPECTS despite an increased risk for sICH. Further data from randomized-controlled clinical trials are needed to elucidate the role of EVT in this subgroup of AIS patients.

REGISTRATION

The protocol has been registered in the International Prospective Register of Ongoing Systematic Reviews PROSPERO; Registration Number: CRD42022334417.

Primary results of mechanical thrombectomy for acute ischemic stroke: The K-NET registry in the Japanese metropolitan area

BACKGROUND

Endovascular treatment (EVT) for acute large vessel occlusion has proven to be effective in randomized controlled trials. We conducted a prospective cohort study to evaluate the real-world efficacy of EVT in a metropolitan area with a large number of comprehensive stroke centers and to compare it with the results of other registries and randomized controlled trials (RCTs).

METHODS

We analyzed the Kanagawa Intravenous and Endovascular Treatment of Acute Ischemic Stroke registry, a prospective, multicenter observational study of patients treated by EVT and/or intravenous tissue-type plasminogen activator (tPA). Of the 2488 patients enrolled from January 2018 to June 2020, 1764 patients treated with EVT were included. The primary outcome was a good outcome, which was defined as a modified Rankin Scale (mRS) of 0-2 at 90 days. Secondary analysis included predicting a good outcome using multivariate logistic regression analysis.

RESULTS

The median age was 77 years, and the median National Institute of Health Stroke Scale (NIHSS) score was 18. Pretreatment mRS score 0-2 was 87%, and direct transport was 92%. The rate of occlusion in anterior circulation was 90.3%. Successful recanalization was observed in 88.7%. The median time from onset to recanalization was 193 min. Good outcomes at 90 days were 43.3% in anterior circulation and 41.9% in posterior circulation. Overall mortality was 12.6%. Significant predictors for a good outcome were as follows: age, male, direct transfer, NIHSS score, Alberta Stroke Program Early Computed Tomography Score, intravenous tPA, and successful recanalization.

CONCLUSION

EVT in routine clinical use in a metropolitan area showed comparable good outcomes and lower mortality compared to previous studies, despite the high proportion of patients with older age, pretreatment mRS score of >2, posterior circulation occlusion, and higher NIHSS. Those results may have been associated with more direct transport and faster onset-to-recanalization times.

By and Large, Thrombectomy in Large Core Is a Palpable Reality

Our Japanese colleagues deserve much praise for finishing the first randomized clinical trial of thrombectomy in Alberta Stroke Program Early CT Score 3 to 5 patients showing an impressive therapy effect of thrombectomy. The predominant use of magnetic resonance imaging for patient selection, the low rate of alteplase therapy and its low dose limit direct comparisons with patients treated outside of Japan. Another limitation is the lack of benefit when using the traditional metric–modified Rankin Scale score 0–2. We consider the results of RESCUE-Japan LIMIT encouraging and a clear motivation to continue and complete other studies.

Endovascular Therapy for Acute Stroke with a Large Ischemic Region

BACKGROUND

Endovascular therapy for acute ischemic stroke is generally avoided when the infarction is large, but the effect of endovascular therapy with medical care as compared with medical care alone for large strokes has not been well studied.

METHODS

We conducted a multicenter, open-label, randomized clinical trial in Japan involving patients with occlusion of large cerebral vessels and sizable strokes on imaging, as indicated by an Alberta Stroke Program Early Computed Tomographic Score (ASPECTS) value of 3 to 5 (on a scale from 0 to 10, with lower values indicating larger infarction). Patients were randomly assigned in a 1:1 ratio to receive endovascular therapy with medical care or medical care alone within 6 hours after they were last known to be well or within 24 hours if there was no early change on fluid-attenuated inversion recovery images. Alteplase (0.6 mg per kilogram of body weight) was used when appropriate in both groups. The primary outcome was a modified Rankin scale score of 0 to 3 (on a scale from 0 to 6, with higher scores indicating greater disability) at 90 days. Secondary outcomes included a shift across the range of modified Rankin scale scores toward a better outcome at 90 days and an improvement of at least 8 points in the National Institutes of Health Stroke Scale (NIHSS) score (range, 0 to 42, with higher scores indicating greater deficit) at 48 hours.

RESULTS

A total of 203 patients underwent randomization; 101 patients were assigned to the endovascular-therapy group and 102 to the medical-care group. Approximately 27% of patients in each group received alteplase. The percentage of patients with a modified Rankin scale score of 0 to 3 at 90 days was 31.0% in the endovascular-therapy group and 12.7% in the medical-care group (relative risk, 2.43; 95% confidence interval [CI], 1.35 to 4.37; P = 0.002). The ordinal shift across the range of modified Rankin scale scores generally favored endovascular therapy. An improvement of at least 8 points on the NIHSS score at 48 hours was observed in 31.0% of the patients in the endovascular-therapy group and 8.8% of those in the medical-care group (relative risk, 3.51; 95% CI, 1.76 to 7.00), and any intracranial hemorrhage occurred in 58.0% and 31.4%, respectively (P<0.001).

CONCLUSIONS

In a trial conducted in Japan, patients with large cerebral infarctions had better functional outcomes with endovascular therapy than with medical care alone but had more intracranial hemorrhages. (Funded by Mihara Cerebrovascular Disorder Research Promotion Fund and the Japanese Society for Neuroendovascular Therapy; RESCUE-Japan LIMIT ClinicalTrials.gov number, NCT03702413.).

Influence of single pass recanalization in acute ischemic stroke with large vessel occlusion in patients of Asian ethnicity

BACKGROUND AND PURPOSE

A previous report revealed single pass recanalization was associated with better functional outcome for patients with acute ischemic stroke with large vessel occlusion in real-world settings. However, the effect of single pass recanalization in acute large vessel occlusion based on the largest registry in real-world settings in Asian population are not well scrutinized.

MATERIALS AND METHODS

RESCUE-Japan Registry-2 was a physician-initiated prospective multicenter registry that enrolled consecutive patients with acute large vessel occlusion who were admitted within 24 h of onset. We compared patients who underwent endovascular therapy and achieved good recanalization in single or multiple device passes (single-pass group and multiple-passes group, respectively) in terms of the good outcome defined as modified Rankin Scale of 0-2 at 90 days after onset. We estimated the odds ratios, safety and mortality adjusting for confounders.

RESULTS

Among 2420 patients registered, 1281 patients treated with endovascular therapy. 829 patients were analyzed (557 patients in single-pass and 272 patients in multiple-passes group). Patient characteristics were almost similar between two groups. The good outcome was more observed of patients in the single groups (51.5% vs 39.3%). The adjusted odds ratio of single pass of good outcome was 1.92 (95% confidence interval, 1.37-2.69). The frequencies of symptomatic intracranial hemorrhage were similar between the two groups.

CONCLUSION

Single pass recanalization was associated with good clinical outcome on real-world settings in Asian population.

Intra- and inter-rater consistency of dual assessment by radiologist and neurologist for evaluating DWI-ASPECTS in ischemic stroke

OBJECTIVES

To estimate the intra -and inter-rater consistency of radiologist and neurologist working in pairs attributing DWI-ASPECTS (Diffusion Alberta Stroke Program Early CT Score) in patients with acute middle cerebral artery ischemic stroke referred for mechanical thrombectomy, intravenous thrombolysis or bridging therapy.

METHODS

Five neurologists and 5 radiologists working in pairs and in hour period scored independently and in two reading sessions anonymized DWI-ASPECTS of 80 patients presenting with acute anterior ischaemic stroke in our center. We measured agreement between pairs using intraclass correlation coefficients (ICCs). A Fleiss kappa was used for dichotomized (0-6;7-10) and trichotomized (0-3;4-6;7-10) ASPECTS. The interrater distribution of the score in the trichotomized (0-3;4-6;7-10) ASPECTS was calculated. We determined the interrater (Cohen kappa) and intrarater (Fleiss kappa) agreement on the ASPECTS regions.

RESULTS

The average DWI-ASPECTS was 6.35 (SD±2.44) for the first reading, and 6.47 (SD±2.44) for the second one. The ICC was 0.853 (95%CI, 0.798-0.896) for the interrater, and 0.862 (95%CI, 0.834-0.885) for the intrarater evaluation. Kappa coefficients were high for dichotomized (k=0.75) and trichotomized (k=0.64) ASPECTS. Evaluators agreement on the ASPECTS category (0-3), (4-6) and (7-10) was 88, 76 and 93% respectively. The anatomic region infarcted was well identified (k=0.70-0.77), except for the internal capsula (k=0.57). Interrater agreement was fair for M5 (k=0.37), moderate for internal capsula (0.52) and substantial for the other regions (0.60-0.79).

CONCLUSIONS

Reliability of DWI-ASPECTS is good when determined by radiologist and neurologist working in pairs, which corresponds to our current clinical practice. However, discrepancies are possible for cut-off determination, which may impact the indication of thrombectomy, and for the determination of the exact infarcted region. Agreement to propose category (4-6) is lower than for (0-3) and (8-10) ASPECTS categories.

Predicting Imaging Outcomes in Acute Stroke Therapy—Comparison of Magnetic Resonance Imaging and Computed Tomography

Background: Imaging of acute stroke patients in emergency settings is critical for treatment decisions. Most commonly, CT with CTA is used worldwide for acute stroke. However, MRI may be advantageous in certain settings. With advancements in endovascular clot retrieval techniques, there is a need to identify and use the best possible imaging for the diagnosis and outcome prediction of hyperacute stroke.

Methods: This mixed retrospective and prospective observational study was conducted over 2 years in patients who underwent reperfusion therapies. Patients were included in this study if they had a baseline as well as follow-up noncontrast CT and diffusion-weighted imaging (DWI) MRI. We compared them for estimating final infarct size and outcomes after reperfusion therapy.

Results: A total of 86 patients were included in the study. Baseline DWI found new infarcts in 33 patients compared to baseline CT. Sensitivity and specificity of CT and DWI in predicting the final infarct size was 75.3% and 76.9% and 97.2% and 92.3%, respectively. A positive correlation of 51.2% and 84.4% was noted between b-CT Alberta stroke programme early CT score (ASPECTS) and b-DWI with 72 hours DWI ASPECTS, respectively (p < 0.001). The positive predictive value of CT was 94.8% and DWI was 98.6%. None of the patients had reversible hyperintensities in the follow-up DWI.

Conclusion: MRI is more sensitive and specific than noncontrast CT in predicting final infarct volume. It predicts final outcomes better and could be an alternative if available in acute stroke settings.

Performance of automated CT ASPECTS in comparison to physicians at different levels on evaluating acute ischemic stroke at a single institution in China

Background

Our aim was to evaluate the sensitivity and specificity of the automated computer-based Alberta Stroke Program Early CT Score (e-ASPECTS) for acute stroke patients and compare the result with physicians at different levels.

Methods

In our center, e-ASPECTS and 9 physicians at different levels retrospectively and blindly assessed baseline computed tomography (CT) images of 55 patients. Sensitivity, specificity, receiver-operating characteristic curves, Bland–Altman plots with mean score error, and Matthews correlation coefficients were calculated. Comparisons were made between the scores by physicians and e-ASPECTS with diffusion-weighted imaging (DWI) being the ground truth. Two methods for clustered data were used to estimate sensitivity and specificity in the region-based analysis.

Results

In total, 1100 (55 patients × 20 regions per patient) ASPECTS regions were scored. In the region-based analysis, sensitivity of e-ASPECTS was better than junior doctors and residents (0.576 vs 0.165 and 0.111, p < 0.05) but inferior to senior doctors (0.576 vs 0.617). Specificity was lower than junior doctors and residents (0.883 vs 0.971 and 0.914) but higher than senior doctors (0.883 vs 0.809, p < 0.05). E-ASPECTS had the best Matthews correlation coefficient of 0.529, compared to senior doctors, junior doctors, and residents (0.463, 0.251, and 0.087, respectively).

Conclusions

e-ASPECTS showed a similar performance to that of senior physicians in the assessment of brain CT of acute ischemic stroke patients with the Alberta Stroke Program Early CT score method.

Identifying Cerebral Large Vessel Occlusion in Acute Ischemic Stroke by MRI Positioning Scanning

Various approaches have been tried for acute ischemic stroke (AIS) treatment to shorten the time from onset to recanalization. MRI positioning scanning (PS), which must be taken before any MRI sequences, was examined whether it can detect cerebral large vessel occlusion. A total of 68 consecutive patients with AIS who underwent MRI and were treated with intravenous recombinant tissue plasminogen activator or mechanical thrombectomy at our hospital were retrospectively included in this study. Occluded vessels were identified on the axial or coronal views of PS images, and these images were compared with 3D time-of-flight MRA and digital subtraction angiogram. The sensitivities, positive predictive values (PPVs), and negative predictive values (NPVs) for internal carotid artery (ICA), the proximal M1, distal M1, and M2 segment of the middle cerebral artery occlusion were assessed, and the number of PS slices was assessed. The sensitivities of the axial slices for ICA, proximal M1, distal M1, and M2 occlusion were 62%, 21%, 35%, and 86%, respectively. The PPVs of the axial slices for ICA, proximal M1, distal M1, and M2 occlusion were 81%, 88%, 100%, and 97%, respectively, and the NPVs of the axial slices for ICA, proximal M1, distal M1, and M2 occlusion were 94%, 90%, 86%, and 100%, respectively. The detection rate for the ICA was significantly higher with three axial slices (91%) than with two slices (47%) (p <0.01). MRI PS is warranted to be referred to detect large cerebral vessel occlusion.

ASPECTS-based selection for late endovascular treatment: a retrospective two-site cohort study

INTRODUCTION

The DAWN trial demonstrated the effectiveness of late endovascular treatment in acute ischemic stroke patients selected on the basis of a clinical-core mismatch. We explored in a real-world sample of endovascular treatment patients if a clinical-ASPECTS (Alberta Stroke Program Early CT Score) mismatch was associated with an outcome benefit after late endovascular treatment.

METHODS

We retrospectively analyzed all consecutive acute ischemic stroke patients admitted 6-24 h after last proof of good health in two stroke centers, with initial National Institutes of Health Stroke Scale (NIHSS) ≥10 and an internal carotid artery or M1 occlusion. We defined clinical-ASPECTS mismatch as NIHSS ≥ 10 and ASPECTS ≥ 7, or NIHSS ≥ 20 and ASPECTS ≥ 5. We assessed the interaction between the presence of the clinical-ASPECTS mismatch and late endovascular treatment using ordinal shift analysis of the three-month modified Rankin Scale and adjusting for multiple confounders.

RESULTS

The included 337 patients had a median age of 73 years (IQR = 61-82), admission NIHSS of 18 (15-22), and baseline ASPECTS of 7 (5-9). Out of 196 (58.2%) patients showing clinical-ASPECTS mismatch, 146 (74.5%) underwent late endovascular treatment. Among 141 (41.8%) mismatch negative patients, late endovascular treatment was performed in 72 (51.1%) patients. In the adjusted analysis, late endovascular treatment was significantly associated with a better outcome in the presence of clinical-ASPECTS mismatch (adjusted odd ratio, aOR = 2.83; 95% confidence interval, CI: 1.48-5.58) but not in its absence (aOR = 1.32; 95%CI: 0.61-2.84). The p-value for the interaction term between clinical-ASPECTS mismatch and late endovascular treatment was 0.073.

CONCLUSIONS

In our retrospective two-site analysis, late endovascular treatment seemed effective in the presence of a clinical-ASPECTS mismatch, but not in its absence. If confirmed in randomized trials, this finding could support the use of an ASPECTS-based selection for late endovascular treatment decisions, obviating the need for advanced imaging.

Modified diffusion-weighted imaging-Alberta Stroke Program Early Computed Tomography Score including deep white matter lesions predicts symptomatic intracerebral hemorrhage following intravenous thrombolysis

The Alberta Stroke Program Early Computed Tomography Score (ASPECTS) is widely used for the assessment of early ischemic changes (EICs) before thrombolysis. However, for symptomatic intracerebral hemorrhage (sICH) following intravenous recombinant tissue plasminogen activator (rt-PA), the prediction abilities of CT-ASPECTS, diffusion-weighted imaging (DWI)-ASPECTS, and DWI-ASPECTS including EICs in deep white matter (DWI-ASPECTS + W) are unclear. We investigated associations between each score and sICH following intravenous rt-PA. Data from consecutive patients who received intravenous rt-PA for acute ischemic stroke from 2005 to 2015 in four hospitals were retrospectively screened. We included data from patients who had undergone both CT and magnetic resonance imaging before thrombolysis and without evidence of posterior circulation stroke. We analyzed the ability of CT-ASPECTS, DWI-ASPECTS, and DWI-ASPECTS + W to predict sICH, accompanied by an increase in the National Institutes of Health Stroke Scale (NIHSS) score of ≥ 4 within the initial 36 h. Of 455 patients (273 men, median 75 years old), sICH occurred in 15 patients (3.3%). Receiver operating characteristics curve analysis showed that the optimal cut-offs of CT-ASPECTS, DWI-ASPECTS, and DWI-ASPECTS + W for predicting sICH were ≤ 9 (sensitivity 60.0%, specificity 59.8%, c-statistic 0.625), ≤ 6 (sensitivity 53.3%, specificity 80.9%, c-statistic 0.718), and ≤ 8 (sensitivity 86.7%, specificity 55.9%, c-statistic 0.756), respectively. A DWI-ASPECTS + W of ≤ 8 was independently associated with sICH (odds ratio 5.21, 95% confidence interval 1.30–35.31) after adjustment for pretreatment with antithrombotic agents, pretreatment NIHSS score, and large artery occlusions. DWI-ASPECTS + W predicted sICH in patients with acute anterior circulation stroke receiving intravenous rt-PA.

Differences between predictive factors for early neurological deterioration due to hemorrhagic and ischemic insults following intravenous recombinant tissue plasminogen activator

Early neurological deterioration (END) following intravenous recombinant tissue plasminogen activator (rt-PA) treatment is a serious clinical event that can be caused by hemorrhagic or ischemic insult. We investigated the differences in predictive factors for END due to hemorrhagic and END due to ischemic insults. Consecutive patients from four hospitals who received 0.6 mg/kg intravenous rt-PA for acute ischemic stroke were retrospectively recruited. END was defined as a National Institutes of Health Stroke Scale (NIHSS) score ≥ 4 points within 24 h compared with baseline. END was classified into those due to hemorrhagic (END_h) or ischemic (END_i) insult based on computed tomography (CT) or magnetic resonance imaging. Risk factors associated with END_h and END_i were investigated by comparison with non-END cases. A total of 744 patients (452 men, median 75 years old) were included. END was observed in 79 patients (10.6%), including 22 END_h (3.0%) and 57 END_i (7.7%), which occurred within a median of 7 h after treatment. Multivariate analyses showed that higher pretreatment NIHSS score (odds ratio [OR] 1.06, 95% confidence interval [CI] 1.00–1.13) and pretreatment with antiplatelets (OR 2.84, 95% CI 1.08–7.72) were associated with END_h. Extensive early ischemic change (Alberta Stroke Program Early CT Score ≤ 7 on CT or ≤ 6 on diffusion-weighted imaging; OR 2.80, 95% CI 1.36–5.64) and large artery occlusions (OR 3.09, 95% CI 1.53–6.57) were associated with END_i. Distinct factors were predictive for the END subtypes. These findings could help develop preventative measures for END in patients with the identified risk factors.

Bridging May Increase the Risk of Symptomatic Intracranial Hemorrhage in Thrombectomy Patients With Low Alberta Stroke Program Early Computed Tomography Score

BACKGROUND AND PURPOSE

Whether intravenous thrombolysis (IVT) increases the risk for symptomatic intracranial hemorrhage (sICH) in patients treated with mechanical thrombectomy (MT) is a matter of debate. Purpose of this study was to evaluate the extent of early ischemia as a possible factor influencing the risk for sICH after IVT+MT versus direct MT.

METHODS

An explorative analysis of the BEYOND-SWIFT (Bernese-European Registry for Ischemic Stroke Patients Treated Outside Current Guidelines With Neurothrombectomy Devices Using the SOLITAIRE FR With the Intention for Thrombectomy) multicenter cohort was performed. We hypothesized that the sICH risk between IVT+MT versus direct MT differs across the strata of Alberta Stroke Program Early CT Scores (ASPECTS). For this purpose, all patients with ICA, M1, and M2 vessel occlusions and available noncontrast computed tomography or diffusion-weighed imaging ASPECTS (n=2002) were analyzed. We used logistic regression analysis in subgroups, as well as interaction terms, to address the risk of sICH in IVT+MT versus direct MT patients across the ASPECTS strata.

RESULTS

In 2002 patients (median age, 73.7 years; 50.7% women; median National Institutes of Health Stroke Scale score, 16), the overall rate of sICH was 6.5% (95% CI, 5.5%-7.7%). Risk of sICH differed across ASPECTS groups (9-10: 6.3%; 6-8: 5.6% and ≤5 9.8%; P=0.042). With decreasing ASPECTS, the risks of sICH in the IVT+MT versus the direct MT group increased from adjusted odds ratio of 0.61 ([95% CI, 0.24-1.60] ASPECTS 9-10), to 1.72 ([95% CI, 0.69-4.24] ASPECTS 6-8) and 6.31 ([95% CI, 1.87-21.29] ASPECTS ≤5), yielding a positive interaction term (1.91 [95% CI, 1.01-3.63]). Sensitivity analyses regarding diffusion-weighed imaging versus noncontrast computed tomography ASPECTS did not alter the primary observations.

CONCLUSIONS

The extent of early ischemia may influence relative risks of sICH in IVT+MT versus direct MT patients, with an excess sICH risk in IVT+MT patients with low ASPECTS. If confirmed in post hoc analyses of randomized controlled trial data, IVT may be administered more carefully in patients with low ASPECTS eligible for and with direct access to MT.

Rapid Treatment of Acute Ischemic Stroke Using a Computed Tomography-Based Reperfusion Protocol: The Reality of a Local Community Hospital with Limited Resources

Objective

In patients with acute ischemic stroke (AIS), prognosis strongly depends on the onset-to-recanalization time. The Ishinomaki protocol for rapid recanalization has been used since October 2017. This protocol determines the indication for reperfusion therapy based on computed tomography (CT)/three-dimensional CT angiography (3DCTA) findings and intends to reduce the onset-to-recanalization time. We aimed to compare the outcomes before and after protocol introduction.

Methods

Our hospital is the only thrombectomy-capable center in Ishinomaki, Tome, and Kesennuma medical area. Before protocol introduction (April 2014-June 2016), both CT and magnetic resonance imaging were performed to determine the indications for intravenous (IV) recombinant tissue-plasminogen activator (rt-PA) or mechanical thrombectomy within 6 hours of disease onset. However, after protocol introduction (from October 2017), plain CT and 3DCTA were used. We collected data on patients who underwent mechanical thrombectomy and/or IV rt-PA before (n = 13) and after (n = 34) the protocol introduction. The required time from onset to door (OTD), door to needle (DTN), needle to puncture (NTP), puncture to recanalization (PTR), and door to recanalization (DTR) were compared before and after protocol introduction. Furthermore, thrombolysis in cerebral infarction (TICI) grades and modified Rankin scale (mRS) scores at discharge were compared.

Results

The outcomes before and after protocol introduction were as follows: OTD: 105 ± 73.8 (mean ± standard deviation) vs. 120 ± 68.1 min (p = 0.376, Mann-Whitney U test); DTN: 62.9 ± 15.9 vs. 41 ± 17 min (p <0.01); NTP: 112 ± 69.8 vs. 39.9 ± 33.7 min (p <0.01); PTR: 87.9 ± 45.4 vs. 52.5 ± 27.9 min (p <0.01); and DTR, 230 ± 69.9 vs. 110 ± 40.3 min (p <0.0001). Before and after protocol introduction, the proportion of patients with TICI grade 2b-3, mRS score of 0-2 at discharge, and mRS score of 5-6 were 54% vs. 50% (p = 0.815, Fisher's exact test), 23% vs. 21% (p = 0.854), and 15% vs. 50% (p = 0.046), respectively.

Conclusion

The Ishinomaki protocol reduced the mean DTR time by 120 min. The reduction in treatment time was due to the change in CT-based recanalization and collaboration with emergency physicians and paramedics. There was no increase in good outcomes, but there was a significant increase in poor outcomes at discharge. Patients who could not be salvaged were indicated for reperfusion therapy as CT and 3DCTA cannot detect the ischemic core.