Mechanical Thrombectomy Outcomes With and Without Intravenous Thrombolysis in Stroke Patients

Shikonin attenuates cerebral ischemia/reperfusion injury via inhibiting NOD2/RIP2/NF-κB-mediated microglia polarization and neuroinflammation

OBJECTIVES

Microglia-mediated neuroinflammation plays a crucial role in the pathophysiological process of multiple neurological disorders such as ischemic stroke, which still lacks effective therapeutic agents. Shikonin possesses anti-inflammatory and neuroprotective properties. However, its underlying mechanism remains elusive. This study aimed to investigate whether Shikonin confers protection against cerebral ischemia/reperfusion (I/R) injury by modulating microglial polarization and elucidate the associated mechanisms.

METHODS

This study employed an oxygen-glucose deprivation and reoxygenation (OGD/R) BV2 microglial cellular model and a middle cerebral artery occlusion/reperfusion (MCAO/R) animal model to investigate the protection and underlying mechanism of Shikonin against ischemic stroke.

RESULTS

The results demonstrated that Shikonin treatment significantly reduced brain infarction volume and improved neurological function in MCAO/R rats. Simultaneously, Shikonin treatment significantly reduced microglial proinflammatory phenotype and levels of proinflammatory markers (inducible-NO synthase (iNOS), tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), and IL-6), increased microglial anti-inflammatory phenotype and levels of anti-inflammatory markers (Arginase-1 (Arg1), transforming growth factor-beta (TGF-β), and IL-10), reversed the expression of Nucleotide-binding oligomerization domain 2 (NOD2) and phosphorylation receptor interacting protein 2 (p-RIP2), and suppressed nuclear factor kappa-B (NF-κB) signaling activation in the ischemic penumbra regions. These effects of Shikonin were further corroborated in OGD/R-treated BV2 cells. Furthermore, overexpression of NOD2 markedly attenuated the neuroprotective effects of Shikonin treatment in MCAO/R rats. NOD2 overexpression also attenuated the regulatory effects of Shikonin on neuroinflammation, microglial polarization, and NF-κB signaling activation.

CONCLUSION

This study illustrates that Shikonin mitigates inflammation mediated by microglial proinflammatory polarization by inhibiting the NOD2/RIP2/NF-κB signaling pathway, thereby exerting a protective role. The findings uncover a potential molecular mechanism for Shikonin in treating ischemic stroke.

Is endovascular treatment alone as effective and safe as that with preceding intravenous thrombolysis for acute ischemic stroke? A meta-analysis of randomized controlled trials

INTRODUCTION

This meta-analysis aimed to evaluate the safety and efficacy of direct endovascular therapy (EVT) and bridging therapy (EVT with preceding intravenous thrombolysis i.e. IVT), in acute anterior circulation, large vessel occlusion stroke.

EVIDENCE ACQUISITION

Following the PRISMA guidelines, a systematic literature review of the English language literature was conducted using PubMed, Cochrane CENTRAL, SCOPUS and ClinicalTrials.gov. Outcomes of interest were measured by the modified Rankin Scale (mRS), and included: no disability (mRS0), no significant disability despite some symptoms (mRS1), slight disability (mRS2), moderate disability (mRS3), moderately severe disability (mRS4), severe disability (mRS5), mortality (mRS6). Additionally, we inspected patients having excellent outcome, functional independence outcome, and poor outcome, along with successful reperfusion and intracranial hemorrhage. We calculated pooled risk ratios (RRs) and their corresponding 95% confidence intervals (CI).

EVIDENCE SYNTHESIS

A total of seven RCTs involving 2,392 patients were finally included. The chances of achieving successful reperfusion were significantly more with IVT+EVT as compared to EVT alone (RR: 0.97; 95% CI: 0.94, 1.00; P=0.03) (I2=0%). There was no significant difference in the number of patients having outcomes ranging from mRS0 to mRS6, excellent outcome, functional independence, poor outcome or incidence of intracranial hemorrhage, who underwent either EVT alone or IVT+EVT.

CONCLUSIONS

Additional trials are needed to determine if the absence of significant differences is due to insufficient sample size or if the combination therapy is truly not beneficial.

Real-world setting comparison of bridging therapy versus direct mechanical thrombectomy for acute ischemic stroke: A meta-analysis

BACKGROUND AND PURPOSE

Intravenous Thrombolysis (IVT) prior to Mechanical Thrombectomy (MT) for Acute Ischaemic Stroke (AIS) due to Large-Vessel Occlusion (LVO) remains controversial. Therefore, the authors performed a meta-analysis of the available real-world evidence focusing on the efficacy and safety of Bridging Therapy (BT) compared with direct MT in patients with AIS due to LVO.

METHODS

Four databases were searched until 01 February 2023. Retrospective and prospective studies from nationwide or health organization registry databases that compared the clinical outcomes of BT and direct MT were included. Odds Ratios (ORs) and 95 % Confidence Intervals (CIs) for efficacy and safety outcomes were pooled using a random-effects model.

RESULTS

Of the 12 studies, 86,695 patients were included. In patients with AIS due to LVO, BT group was associated with higher odds of achieving excellent functional outcome (modified Rankin Scale score 0-1) at 90 days (OR = 1.48, 95 % CI 1.25-1.75), favorable discharge disposition (to the home with or without services) (OR = 1.33, 95 % CI 1.29-1.38), and decreased mortality at 90 days (OR = 0.62, 95 % CI 0.56-0.70), as compared with the direct MT group. In addition, the risk of symptomatic intracranial hemorrhage did not increase significantly in the BT group.

CONCLUSION

The present meta-analysis indicates that BT was associated with favorable outcomes in patients with AIS due to LVO. These findings support the current practice in a real-world setting and strengthen their validity. For patients eligible for both IVT and MT, BT remains the standard treatment until more data are available.

Efficacy and safety of mechanical thrombectomy in the posterior cerebral circulation-a single center study

Mechanical thrombectomy (MT) is the current standard treatment for strokes in the anterior cerebral circulation (AMT) and has recently been proven to be beneficial in the posterior circulation strokes (PMT). Our study aims to evaluate parameters for favorable outcomes in PMT-patients and to compare the clinical characteristics of individuals who received AMT and PMT. For this purpose, we confronted AMT and PMT-receipients and performed a multivariate regression analysis to assess the influence of factors on favorable outcomes in the study group and in the AMT and PMT subgroups. When analysing 623 MT-patients, those who received PMT had significantly lower admission National Institutes of Health Stroke Scale (NIHSS) scores (9 vs. 13; p < 0.001) and 24 h post-MT (7 vs. 12; p = 0.006). Key parameters influencing the favorable outcomes of PMT at discharge and at 90th day include: NIHSS scores (OR: 0.865, 95% CI: 0.813-0.893, and OR: 0.900, 95% CI: 0.861-0.925), MT time (OR: 0.993, 95% CI: 0.987-0.998 and OR: 0.993, 95% CI: 0.990-0.997), and leukocytosis (OR: 0.961, 95% CI: 0.928-0.988 and OR: 0.974, 95% CI: 0.957-0.998). Different clinical profiles exist between AMT and PMT-recipients, with the neurological status post-MT being decisive for the prognosis. Several factors play an important role in predicting outcome, especially in the PMT group.

iSPAN: Explainable prediction of outcomes post thrombectomy with Machine Learning

PURPOSE

This study aimed to develop and evaluate a machine learning model and a novel clinical score for predicting outcomes in stroke patients undergoing endovascular thrombectomy.

MATERIALS AND METHODS

This retrospective study included all patients aged over 18 years with an anterior circulation stroke treated at a thrombectomy centre from 2010 to 2020 with external validation. The primary outcome was day 90 mRS ≥3. Existing clinical scores (SPAN and PRE) and Machine Learning (ML) models were compared. A novel clinical score (iSPAN) was derived by adding an optimised weighting of the most important ML features to the SPAN.

RESULTS

812 patients were initially included (397 female, average age 73), 63 for external validation. The best performing clinical score and ML model were SPAN and XGB (sensitivity, specificity and accuracy 0.290, 0.967, 0.628 and 0.693, 0.783, 0.738 respectively). A significant difference was found overall and our XGB model was more accurate than SPAN (p < 0.0018). The most important features were Age, mTICI and total number of passes. The addition of 11 points for mTICI of ≤2B and 3 points for ≥3 passes to the SPAN achieved the best accuracy and was used to create the iSPAN. iSPAN was not significantly less accurate than our XGB model (p > 0.5). In the external validation set, iSPAN and SPAN achieved sensitivity, specificity, and accuracy of (0.735, 0.862, 0.79) and (0.471, 0.897, 0.67) respectively.

CONCLUSION

iSPAN incorporates machine-derived features to achieve better predictions compared to existing clinical scores. It is not inferior to our XGB model and is externally generalisable.

Effect of Clot Burden Score on Safety and Efficacy of Intravenous Alteplase Prior to Mechanical Thrombectomy in Acute Ischemic Stroke: A Subgroup Analysis of a Randomized Phase 3 Trial

BACKGROUND AND PURPOSE

Whether thrombus burden in acute ischemic stroke modify the effect of intravenous thrombolysis (IVT) before mechanical thrombectomy (MT) remains uncertain. We aim to investigate the treatment effect of stratified clot burden score (CBS) on the efficacy and safety of direct versus bridging MT.

MATERIALS AND METHODS

This is an exploratory subgroup analysis of a randomized trial evaluating the effect of CBS on clinical outcome in the DIRECT-MT trial. CBS was divided into 3 groups (0-3, 4-6, and 7-10) based on preoperative CTA, where higher scores indicated a lower clot burden. We report the adjusted common odds ratio for a shift toward better outcomes on the mRS after thrombectomy alone compared with combination treatment by stratified CBS groups.

RESULTS

No modification effect of mRS distribution was observed by CBS subgroups (CBS 0-3: adjusted common ratio odds 1.519 [95% CI, 0.928-2.486]; 4-6: 0.924 [0.635-1.345]; 7-10: 1.040 [0.481-2.247]). Patients with CBS 4-6 had a higher rate of early reperfusion (adjusted OR (aOR), 0.3 [95% CI, 0.1-0.9]), final reperfusion (aOR 0.5 [95% CI, 0.3-0.9]), and fewer thrombectomy attempts (aOR 0.4 [95% CI, 0.1-0.7]). Patients with CBS 7-10 had a higher rate of asymptomatic intracranial hemorrhage (14.9% versus 36.8%, P = .0197) for bridging MT. No significant difference was observed in other safety outcomes by trichotomized CBS.

CONCLUSIONS

The subgroup analysis of DIRECT-MT suggested that thrombus burden did not alter the treatment effect of IVT before MT on functional outcomes in CBS subgroups.

Endovascular thrombectomy without versus with different pre-intravenous thrombolysis in acute ischemic stroke: a network meta-analysis of randomized controlled trials

Background

The current guideline recommended the use of intravenous thrombolysis (IVT) before Endovascular thrombectomy (EVT), but the effectiveness and safety of tenecteplase compare to alteplase in patients before EVT remain uncertain.

Methods

We searched PubMed, Embase, Web of Science, and the Cochrane Library to identify eligible articles from inception until September 16, 2023. The primary outcome was functional independence (mRS 0-2) at 90 days. Secondary outcomes included excellent outcome (mRS 0-1) at 90 days, all-cause mortality at follow-up, successful reperfusion (TICI 2b-3) after the end of EVT, symptomatic intracranial hemorrhage (sICH) or any intracranial hemorrhage (aICH). The PROSPERO registration number is CRD42023470419.

Results

Eight randomized controlled trials (RCTs) were included involving 2,836 acute ischemic stroke (AIS) patients. Compared to EVT alone, tenecteplase (0.25 mg/kg and 0.4 mg/kg) + EVT and 0.9 mg/kg alteplase + EVT were significant difference associated with higher successful reperfusion (TICI 2b-3) after the end of EVT (RR = 2.31; 95% CI 1.15-4.63; RR = 2.31; 95% CI 1.00-5.33; RR = 1.05; 95% CI 1.01-1.09). And compared to 0.25 mg/kg tenecteplase + EVT, alteplase (0.6 mg/kg and 0.9 mg/kg) + EVT were significant difference associated with lower successful reperfusion (TICI 2b-3) after the end of EVT (RR = 0.45; 95% CI 0.22-0.90; RR = 0.45; 95% CI 0.23-0.91). The risk of aICH (RR = 1.50; 95% CI 1.07-2.09) was significantly higher for 0.6 mg/kg alteplase + EVT than EVT alone. There was no significant difference in functional independence (mRS 0-2), excellent outcome (mRS 0-1), all-cause mortality or sICH among the different IVT strategies (0.25 mg/kg or 0.4 mg/kg tenecteplase and 0.6 mg/kg or 0.9 mg/kg alteplase) before EVT.

Conclusion

The use of alteplase before EVT may potentially improve the successful reperfusion after EVT compared to tenecteplase. Due to the insufficient sample size, more high-quality RCTs are needed to confirm effectiveness and safety of tenecteplase compare to alteplase in patients before EVT.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier: CRD42023470419.

The Association between CYP2C19 Genetic Polymorphism and Prognosis in Patients Receiving Endovascular Therapy

Background

Potentially substantial impacts on the prognosis have been observed in individuals undergoing endovascular treatment due to cytochrome P450 2c19 (CYP2C19) polymorphism. In an attempt to improve prognosis and lower the recurrence rate, this study investigated the CYP2C19 polymorphism in acute ischemic stroke patients.

Materials and Methods

A retrospective analysis was performed on 292 patients with cerebral infarction who had acute endovascular recanalization at the Department of Neurology of Chongqing Hospital of Traditional Chinese Medicine between May 2017 and 2019. The patients were categorized into rapid-, medium-, and slow-metabolism groups based on CYP2C19 gene polymorphism, and their prognosis was monitored. In addition, the prognosis of 188 patients selectively receiving carotid artery stenting at a selected time was also observed.

Results

Among the 292 cerebral infarction cases receiving acute endovascular recanalization, the patients in the CYP2C19 rapid-metabolism group regularly took clopidogrel and aspirin combined with antiplatelet therapy and suffered from reoccurrence of apoplexy and cerebral hemorrhage; the 90-day good prognosis had a statistical difference (P < 0.05, prognostic assessment includes hospitalization and 6 months after discharge) and the other adverse events had no statistical difference (including mortality). The 188 patients selectively receiving carotid artery stenting had a recurrence of apoplexy, cerebral hemorrhage, and restenosis rate with a statistical difference (P < 0.05), and the other adverse events had no statistical difference.

Conclusions

In conclusion, the findings of the current study indicate that irrespective of whether patients are undergoing selective carotid artery stenting or acute endovascular recanalization, those with rapid CYP2C19 metabolism have a significantly lower likelihood of experiencing adverse prognostic events compared to those with intermediate and slow metabolism. Furthermore, this group also has a more favorable prognosis than the other two groups.

Endovascular Thrombectomy With or Without Thrombolysis for Stroke: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background

To this date, whether to administer intravenous thrombolysis (IVT) prior to endovascular thrombectomy (EVT) for stroke patients still stirs some debate. We aimed to systematically update the evidence from randomized trials comparing EVT alone vs EVT with bridging IVT.

Methods

We searched MEDLINE, EMBASE, and the Cochrane Library to identify randomized controlled trials (RCTs) comparing EVT with or without IVT in patients presenting with stroke secondary to a large vessel occlusion. We conducted meta-analyses using random-effects models to compare functional independence, mortality, and symptomatic intracranial hemorrhage (sICH), between EVT and EVT with IVT. We assessed risk of bias using the Cochrane risk-of-bias tool and certainty of evidence for each outcome using the GRADE approach.

Results

Of 11,111 citations, we included 6 studies with a total of 2336 participants. We found low-certainty evidence of possibly a small decrease in the proportion of patients with functional independence (risk difference [RD] -2.0%, 95% CI -5.9% to 2.0%), low-certainty evidence that there is possibly a small increase in mortality (RD 1.0%, 95% CI -2.2% to 4.7%), and moderate-certainty evidence that there is probably a decrease in sICH (RD -1.0%, 95% CI -1.6% to .7%) for patients with EVT alone compared to EVT plus IVT, respectively.

Conclusion

Low-certainty evidence shows that there is possibly a small decrease in functional independence, low-certainty evidence shows that there is possibly a small increase in mortality, and moderate-certainty evidence that there is probably a decrease in sICH for patients with EVT alone compared to EVT plus IVT.

Meta-analysis of direct endovascular thrombectomy vs bridging therapy in the management of acute ischemic stroke with large vessel occlusion

BACKGROUND

Debates persist when using intravenous thrombolysis (IVT) before mechanical thrombectomy (MT) for acute ischemic stroke (AIS) due to large-vessel occlusion (LVO). This systematic review and meta-analysis synthesized evidence on outcomes in patients with acute ischemic stroke due to large vessel occlusion (AIS-LVO), comparing bridging therapy (BT) with MT alone.

METHOD

We conducted searches of PubMed, Scopus, Web of Science, and the Cochrane Central Register of Controlled Trials from inception to July 2023 to identify pertinent clinical trials and observational studies.

RESULT

76 studies, involving 37,658 patients, revealed no significant difference in 90-day functional independence between DEVT and BT. However, a trend favoring BT for achieving functional independence with a modified Rankin Scale (mRS) of 0-1 was observed, having Odds ratio (OR) of 0.75 (95% CI 0.66-0.86; p < 0.001). DEVT was associated with higher postprocedural mortality (OR 1.44;95% CI 1.25-1.65; p < 0.001), but a lower risk of symptomatic intracranial hemorrhage compared to BT (OR 0.855; 95% CI 0.621-1.177; p = 0.327). Successful recanalization rates favored BT, emphasizing the importance of individualized treatment decisions (OR 0.759; 95% CI 0.594-0.969; p = 0.027). Sensitivity analyses were conducted to identify key contributors to heterogeneity.

CONCLUSION

Our meta-analysis underscores the intricate equilibrium between functional efficacy and safety in the evaluation of DEVT and BT for ACS-LVO. Fundamentally, while BT appears more efficacious, concerns about safety arise due to the superior safety profile demonstrated by DEVT. Individualized treatment decisions are imperative, and further trials are warranted to enhance precision in clinical guidance.

Predictive Factors of First-Pass Effect in Patients Who Underwent Successful Endovascular Thrombectomy for Emergent Large Vessel Occlusion

OBJECTIVE

The primary treatment goal of current endovascular thrombectomy (EVT) for emergent large-vessel occlusion (ELVO) is complete recanalization after a single maneuver, referred to as the 'first-pass effect' (FPE). Hence, we aimed to identify the predictive factors of FPE and assess its effect on clinical outcomes in patients with ELVO of the anterior circulation.

METHODS

Among the 129 patients who participated, 110 eligible patients with proximal ELVO (intracranial internal carotid artery and proximal middle cerebral artery) who achieved successful recanalization after EVT were retrospectively reviewed. A comparative analysis between patients who achieved FPE and all others (defined as a non-FPE group) was performed regarding baseline characteristics, clinical variables, and clinical outcomes. Multivariate logistic regression analyses were subsequently conducted for potential predictive factors with p<0.10 in the univariate analysis to determine the independent predictive factors of FPE.

RESULTS

FPE was achieved in 31 of the 110 patients (28.2%). The FPE group had a significantly higher level of functional independence at 90 days than did the non-FPE group (80.6% vs. 50.6%, p=0.002). Pretreatment intravenous thrombolysis (IVT) (odds ratio [OR], 3.179; 95% confidence interval [CI], 1.025-9.861; p=0.045), door-to-puncture (DTP) interval (OR, 0.959; 95% CI, 0.932-0.987; p=0.004), and the use of balloon guiding catheter (BGC) (OR, 3.591; 95% CI, 1.231-10.469; p=0.019) were independent predictive factors of FPE.

CONCLUSION

In conclusion, pretreatment IVT, use of BGC, and a shorter DTP interval were positively associated with FPE, increasing the chance of acquiring better clinical outcomes.

Mechanical thrombectomy in young patients with large vessel occlusion-related ischemic stroke: Data from the Italian Registry of Endovascular Treatment in Acute Stroke

BACKGROUND AND PURPOSE

The weight of outcome predictors in acute ischemic stroke (AIS) patients older than 60 years is not necessarily mirrored in the younger population, posing the question of whether outcome determinants specific for the latter might vary. Very few data are available on predictors of outcome in young AIS patients receiving endovascular treatment (EVT).

METHODS

We analyzed data for patients aged between 16 and 55 years from the Italian Registry of Endovascular Treatment in Acute Stroke. We divided our population into patients <45 years old and patients aged between 45 and 55 years. After testing the differences between groups in terms of 90-day modified Rankin Scale (mRS) 0-2, mortality, and symptomatic intracranial hemorrhage, we looked for predictors of poor outcome (mRS 3-6), death, and symptomatic intracerebral hemorrhage in the two groups.

RESULTS

A total of 438 patients younger than 45 years and 817 aged 45-55 years were included; 284 (34.8%) patients aged 45-55 years and 112 (25.6%) patients younger than 45 years old showed poor 90-day functional outcome (p = 0.001). Predictors of poor outcome in the older group were baseline National Institutes of Health Stroke Scale (NIHSS; p < 0.001), diabetes (p = 0.027), poor collateral status (p = 0.036), and groin puncture-to-recanalization time (p = 0.010), whereas Thrombolysis in Cerebral Infarction (TICI) 2b-3 had an inverse association (p < 0.001). Predictors of poor outcome in patients younger than 45 years were baseline NIHSS (p < 0.001) and groin puncture-to-recanalization time (p = 0.015), whereas an inverse association was found for baseline Alberta Stroke Program Early CT Score (p = 0.010) and TICI 2b-3 (p < 0.001).

CONCLUSIONS

Approximately one third of young adults treated with EVT do not reach a good functional outcome. Fast and successful recanalization, rather than common risk factors, has a major role in determining clinical outcome.

Association of intravenous thrombolysis and pre-interventional reperfusion: a post hoc analysis of the SWIFT DIRECT trial

BACKGROUND

A potential benefit of intravenous thrombolysis (IVT) before mechanical thrombectomy (MT) is pre-interventional reperfusion. Currently, there are few data on the occurrence of pre-interventional reperfusion in patients randomized to IVT or no IVT before MT.

METHODS

SWIFT DIRECT (Solitaire With the Intention For Thrombectomy Plus Intravenous t-PA vs DIRECT Solitaire Stent-retriever Thrombectomy in Acute Anterior Circulation Stroke) was a randomized controlled trial including acute ischemic stroke IVT eligible patients being directly admitted to a comprehensive stroke center, with allocation to IVT with MT versus MT alone. The primary endpoint of this analysis was the occurrence of pre-interventional reperfusion, defined as a pre-interventional expanded Thrombolysis in Cerebral Infarction score of ≥2a. The effect of IVT and potential treatment effect heterogeneity were analyzed using logistic regression analyses.

RESULTS

Of 396 patients, pre-interventional reperfusion occurred in 20 (10.0%) patients randomized to IVT with MT, and in 7 (3.6%) patients randomized to MT alone. Receiving IVT favored the occurrence of pre-interventional reperfusion (adjusted OR 2.91, 95% CI 1.23 to 6.87). There was no IVT treatment effect heterogeneity on the occurrence of pre-interventional reperfusion with different strata of Randomization-to-Groin-Puncture time (p for interaction=0.33), although the effect tended to be stronger in patients with a Randomization-to-Groin-Puncture time >28 min (adjusted OR 4.65, 95% CI 1.16 to 18.68). There were no significant differences in rates of functional outcomes between patients with and without pre-interventional reperfusion.

CONCLUSION

Even for patients with proximal large vessel occlusions and direct access to MT, IVT resulted in an absolute increase of 6% in rates of pre-interventional reperfusion. The influence of time strata on the occurrence of pre-interventional reperfusion should be studied further in an individual patient data meta-analysis of comparable trials.

TRIAL REGISTRATION NUMBER

clinicaltrials.gov NCT03192332.

The Value of Applying Machine Learning in Predicting the Time of Symptom Onset in Stroke Patients: Systematic Review and Meta-Analysis

BACKGROUND

Machine learning is a potentially effective method for identifying and predicting the time of the onset of stroke. However, the value of applying machine learning in this field remains controversial and debatable.

OBJECTIVE

We aimed to assess the value of applying machine learning in predicting the time of stroke onset.

METHODS

PubMed, Web of Science, Embase, and Cochrane were comprehensively searched. The C index and sensitivity with 95% CI were used as effect sizes. The risk of bias was evaluated using PROBAST (Prediction Model Risk of Bias Assessment Tool), and meta-analysis was conducted using R (version 4.2.0; R Core Team).

RESULTS

Thirteen eligible studies were included in the meta-analysis involving 55 machine learning models with 41 models in the training set and 14 in the validation set. The overall C index was 0.800 (95% CI 0.773-0.826) in the training set and 0.781 (95% CI 0.709-0.852) in the validation set. The sensitivity and specificity were 0.76 (95% CI 0.73-0.80) and 0.79 (95% CI 0.74-0.82) in the training set and 0.81 (95% CI 0.68-0.90) and 0.83 (95% CI 0.73-0.89) in the validation set, respectively. Subgroup analysis revealed that the accuracy of machine learning in predicting the time of stroke onset within 4.5 hours was optimal (training: 0.80, 95% CI 0.77-0.83; validation: 0.79, 95% CI 0.71-0.86).

CONCLUSIONS

Machine learning has ideal performance in identifying the time of stroke onset. More reasonable image segmentation and texture extraction methods in radiomics should be used to promote the value of applying machine learning in diverse ethnic backgrounds.

TRIAL REGISTRATION

PROSPERO CRD42022358898; https://www.crd.york.ac.uk/Prospero/display_record.php?RecordID=358898.

Clinical evidence comparing bridging and direct endovascular thrombectomy: progress and controversies

Clinical evidence comparing bridging endovascular thrombectomy (bEVT) with intravenous thrombolysis and direct endovascular thrombectomy (dEVT) without thrombolysis for patients with acute ischemic stroke (AIS) presented directly to an EVT-capable center is overwhelming but inconsistent. This study aimed to analyze the progress and controversies in clinical evidence based on current meta-analyses. Three databases, including MEDLINE, EMBASE, and the Cochrane Library, were searched. Relevant data were extracted and reviewed from the pooled studies. The Assessment of Multiple Systematic Review (AMSTAR-2) was used for quality assessment. Twenty-five meta-analyses were finally included. There were 56% (14/25) from Asian countries, 20% (5/25) from North America, and 24% (6/25) from Europe. The majority (72%, 18/25) of evidence arose in a short period from 2020 to 2022 with the serial publication of four randomized controlled trials (RCTs). Among the 25 meta-analyses, 11 pooled at least three RCTs but there is substantial overlap among seven (five recruited the same four RCTs solely and two recruited the same three RCTs solely). Meanwhile, quality rating based on AMSTAR-2 showed 16 'high' rated studies (64%). For functional independence, 40% (10/25) of studies favored bEVT and 60% showed neutral results. For symptomatic intracerebral hemorrhage, most studies (82.6%, 19/23) showed no significant difference. Non-RCT studies contributed to evidence favoring bEVT. Current RCTs provide an update of clinical evidence comparing bEVT and dEVT. However, they simultaneously contribute to an unnecessary overlap among studies. Contemporary observational studies demonstrated different but possibly confounded evidence. Thus, this issue still requires more clinical evidence under standard procedures.

Endovascular treatment for acute ischemic stroke in patients with tandem lesion in the anterior circulation: analysis from the METRICS study

BACKGROUND

Acute ischemic stroke (AIS) due to anterior circulation tandem lesion (TL) remains a technical and clinical challenge for endovascular treatment (EVT). Conflicting results from observational studies and missing evidence from the randomized trials led us to report a recent real-world multicenter clinical experience and evaluate possible predictors of good outcome after EVT.

METHODS

We analyzed all AIS patients with TL enrolled in the prospective national study METRICS (Mechanical Thrombectomy Quality Indicators Study in Czech Stroke Centers). A good 3-month clinical outcome was scored as 0-2 points in modified Rankin Scale (mRS), achieved recanalization using the Thrombolysis In Cerebral Infarction (TICI) scale and symptomatic intracerebral hemorrhage (sICH) according to the Safe Implementation of Thrombolysis in Stroke-Monitoring Study (SITS-MOST) criteria.

RESULTS

Of 1178 patients enrolled in METRICS, 194 (19.2%) (59.8% males, mean age 68.7±11.5 years) were treated for TL. They did not differ in mRS 0-2 (48.7% vs 46.7%; p=0.616), mortality (17.3% vs 22.7%; p=0.103) and sICH (4.7% vs 5.1%; p=0.809) from those with single occlusion (SO). More TL patients with prior intravenous thrombolysis (IVT) reached TICI 3 (70.3% vs 50.8%; p=0.012) and mRS 0-2 (55.4% vs 34.4%; p=0.007) than those without IVT. No difference was found in the rate of sICH (6.2% vs 1.6%; p=0.276). Multivariate logistic regression analysis showed prior IVT as a predictor of mRS 0-2 after adjustment for potential confounders (OR 3.818, 95% CI 1.614 to 9.030, p=0.002).

CONCLUSION

Patients with TL did not differ from those with SO in outcomes after EVT. TL patients with prior IVT had more complete recanalization and mRS 0-2 and IVT was found to be a predictor of good outcome after EVT.

Endovascular thrombectomy with or without thrombolysis bridging in patients with acute ischaemic stroke: protocol for a systematic review, meta-analysis of randomised trials and cost-effectiveness analysis

INTRODUCTION

Current published guidelines and meta-analyses comparing endovascular thrombectomy (EVT) alone versus EVT with bridging intravenous thrombolysis (IVT) suggest that EVT alone is non-inferior to EVT with bridging thrombolysis in achieving favourable functional outcome. Because of this controversy, we aimed to systematically update the evidence and meta-analyse data from randomised trials comparing EVT alone versus EVT with bridging thrombolysis, and performed an economic evaluation comparing both strategies.

METHODS AND ANALYSIS

We will conduct a systematic review of randomised controlled trials comparing EVT with or without bridging thrombolysis in patients presenting with large vessel occlusions. We will identify eligible studies by systematically searching the following databases from inception without any language restrictions: MEDLINE (through Ovid), Embase and the Cochrane Library. The following criteria will be used to assess eligibility for inclusion: (1) adult patients ≥18 years old; (2) randomised patients to EVT alone or to EVT with IVT; and (3) measured outcomes, including functional outcomes, at least 90 days after randomisation. Pairs of reviewers will independently screen the identified articles, extract information and assess the risk of bias of eligible studies. We will use the Cochrane Risk-of-Bias tool to evaluate risk of bias. We will also use the Grading of Recommendations, Assessment, Development and Evaluation approach to assess the certainty in evidence for each outcome. We will then perform an economic evaluation based on the extracted data.

ETHICS AND DISSEMINATION

This systematic review will not require a research ethics approval because no confidential patient data will be used. We will disseminate our findings by publishing the results in a peer-reviewed journal and via presentation at conferences.

PROSPERO REGISTRATION NUMBER

CRD42022315608.

In a hub-and-spoke network, spoke-administered thrombolysis reduces mechanical thrombectomy procedure time and number of passes

BACKGROUND

The utility of intravenous thrombolysis (IVT) prior to mechanical thrombectomy (MT) in large vessel occlusion stroke (LVO) is controversial. Some data suggest IVT increases MT technical difficulty. Within our hub-and-spoke telestroke network, we examined how spoke-administered IVT affected hub MT procedure time and pass number.

METHODS

Patients presenting to 25 spoke hospitals who were transferred to the hub and underwent MT from 2018 to 2020 were identified from a prospectively maintained database. MT procedure time, fluoroscopy time, and pass number were obtained from operative reports.

RESULTS

Of 107 patients, 48 received IVT at spokes. Baseline characteristics and NIHSS were similar. The last known well (LKW)-to-puncture time was shorter among IVT patients (4.3 ± 1.9 h vs. 10.5 ± 6.5 h, p < 0.0001). In patients that received IVT, mean MT procedure time was decreased by 18.8 min (50.5 ± 29.4 vs. 69.3 ± 46.7 min, p = 0.02) and mean fluoroscopy time was decreased by 11.3 min (21.7 ± 15.8 vs. 33.0 ± 30.9 min, p = 0.03). Furthermore, IVT-treated patients required fewer MT passes (median 1 pass [IQR 1.0, 1.80] vs. 2 passes [1.0, 2.3], p = 0.0002) and were more likely to achieve reperfusion in ≤2 passes (81.3% vs. 59.3%, p = 0.01). An increased proportion of IVT-treated patients achieved TICI 2b-3 reperfusion after MT (93.9% vs. 83.8%, p = 0.045). There were no associations between MT procedural characteristics and LKW-to-puncture time.

CONCLUSION

Within our network, hub MT following spoke-administered IVT was faster, required fewer passes, and achieved improved reperfusion. This suggests spoke-administered IVT does not impair MT, but instead may enhance it.

Bridging Thrombolysis Before Endovascular Therapy in Stroke Patients With Faster Core Growth

BACKGROUND AND OBJECTIVES

It is still uncertain that going direct to endovascular thrombectomy (EVT) leads to equivalent outcomes as bridging IV thrombolysis (IVT) in acute ischemic patients. This study aimed to explore whether the rate of ischemic core growth influenced the patient outcomes after bridging IVT vs direct EVT.

METHODS

This was a retrospective cohort study based on the International Stroke Perfusion Imaging Registry (INSPIRE). It selected acute ischemic stroke patients receiving perfusion CT within 4.5 hours of stroke onset. Patients who went direct to EVT were compared with those who received bridging treatment of IVT before EVT. Ischemic core growth rate was estimated by the acute ischemic core volume on perfusion CT divided by the time from stroke onset to perfusion CT, based on the assumption of a linear growth pattern of ischemic core. Core growth rate was stratified into fast (>15 mL/h) and slow (≤15 mL/h), based on its interaction with bridging IVT in predicting the primary outcome. The primary outcome was modified Rankin scale of 0-2 at 3 months. The secondary outcomes included successful thrombectomy reperfusion defined by modified Thrombolysis in Cerebral Infarction score of 2b-3 and time from groin puncture to reperfusion.

RESULTS

Of the 1,221 EVT patients in the INSPIRE, 323 patients were selected, of which 82 patients received direct EVT and 241 patients received bridging IVT. Bridging IVT was associated with a higher rate of good clinical outcome among patients with fast core growth (39% vs 7% for direct EVT, odds ratio [OR] 8.75 [1.96-39.1], p = 0.005), but the difference was not notable for patients with slow core growth (55% vs 55% for direct EVT, OR 1.00 [0.53-1.87], p = 0.989). In patients with fast core growth, the bridging and direct EVT patients showed no difference in the reperfusion rate (80% vs 76%, p = 0.616). However, patients who received bridging IVT were more likely to achieve reperfusion earlier (the median groin to reperfusion time of 63.0 vs 94.0 minutes, p = 0.005).

DISCUSSION

Patients with fast core growth were more likely to benefit from bridging IVT. This is likely because prior IVT facilitates clot removal and thus reduces time to reperfusion.

Association Between Intravenous Thrombolysis and Clinical Outcomes Among Patients With Ischemic Stroke and Unsuccessful Mechanical Reperfusion

Importance

Clinical evidence of the potential treatment benefit of intravenous thrombolysis preceding unsuccessful mechanical thrombectomy (MT) is scarce.

Objective

To determine whether intravenous thrombolysis (IVT) prior to unsuccessful MT improves functional outcomes in patients with acute ischemic stroke.

Design, Setting, and Participants

Patients were enrolled in this retrospective cohort study from the prospective, observational, multicenter German Stroke Registry-Endovascular Treatment between May 1, 2015, and December 31, 2021. This study compared IVT plus MT vs MT alone in patients with acute ischemic stroke due to anterior circulation large-vessel occlusion in whom mechanical reperfusion was unsuccessful. Unsuccessful mechanical reperfusion was defined as failed (final modified Thrombolysis in Cerebral Infarction grade of 0 or 1) or partial (grade 2a). Patients meeting the inclusion criteria were matched by treatment group using 1:1 propensity score matching.

Interventions

Mechanical thrombectomy with or without IVT.

Main Outcomes and Measures

Primary outcome was functional independence at 90 days, defined as a modified Rankin Scale score of 0 to 2. Safety outcomes were the occurrence of symptomatic intracranial hemorrhage and death.

Results

After matching, 746 patients were compared by treatment arms (median age, 78 [IQR, 68-84] years; 438 women [58.7%]). The proportion of patients who were functionally independent at 90 days was 68 of 373 (18.2%) in the IVT plus MT and 42 of 373 (11.3%) in the MT alone group (adjusted odds ratio [AOR], 2.63 [95% CI, 1.41-5.11]; P = .003). There was a shift toward better functional outcomes on the modified Rankin Scale favoring IVT plus MT (adjusted common OR, 1.98 [95% CI, 1.35-2.92]; P < .001). The treatment benefit of IVT was greater in patients with partial reperfusion compared with failed reperfusion. There was no difference in symptomatic intracranial hemorrhages between treatment groups (AOR, 0.71 [95% CI, 0.29-1.81]; P = .45), while the death rate was lower after IVT plus MT (AOR, 0.54 [95% CI, 0.34-0.86]; P = .01).

Conclusions and Relevance

These findings suggest that prior IVT was safe and improved functional outcomes at 90 days. Partial reperfusion was associated with a greater treatment benefit of IVT, indicating a positive interaction between IVT and MT. These results support current guidelines that all eligible patients with stroke should receive IVT before MT and add a new perspective to the debate on noninferiority of combined stroke treatment.

Endovascular thrombectomy with or without intravenous thrombolysis in large-vessel ischemic stroke: A non-inferiority meta-analysis of 6 randomised controlled trials

BACKGROUND

It is unclear whether thrombectomy alone is non-inferior to thrombectomy with intravenous thrombolysis in patients with acute ischemic stroke due to large-vessel occlusion.

PURPOSE

To perform a comprehensive, trial-level data, non-inferiority meta-analysis of randomised controlled trials comparing endovascular thrombectomy with and without intravenous thrombolysis in patients with ischemic stroke due to large-vessel occlusion of anterior circulation.

METHODS

The prespecified primary efficacy outcome was functional independence, defined as a modified Rankin scale (mRS)score of 0 to 2 at 90 days. The two prespecified non-inferiority margins were risk differences of -10% and - 5%. The study was registered in PROSPERO (CRD42022361110) and conducted according to PRISMA guidelines.

RESULTS

Six trials were included in this analysis (DIRECT-MT, DEVT, SKIP, MR CLEAN-NO IV, DIRECT-SAFE and SWIFT DIRECT) comprising a total of 2334 patients. Functional independence at 90 days was achieved by 570 (49·0%) of 1164 patients in the thrombectomy alone group and 595 (50·9%) of 1170 patients in the thrombectomy with thrombolysis group (pooled risk difference - 0·02, [95% CI -0·06-0·02]). Combined thrombectomy and thrombolysis were associated with significantly higher rates of successful reperfusion (pooled risk ratio 0·96 [95% CI, 0·93-0·99], p = 0·006) but at the expense of a significantly increased risk of overall - but not symptomatic - intracranial haemorrhage (pooled risk ratio 0·87 [95% CI, 0·77-0·98], p = 0·02).

CONCLUSIONS

Compared with a combined treatment approach, thrombectomy alone was non-inferior at -10% non-inferiority margin, but not at a - 5% inferiority margin for functional independence. Current evidence cannot exclude clinically important differences between the two treatment approaches.

NIMBUS geometric clot extractor for challenging clots: Real-world clinical experience and clot composition

PURPOSE

Revascularization rates following mechanical thrombectomy (MT) for acute ischemic stroke (AIS) remain suboptimal for patients with fibrin-rich, recalcitrant clots. The NIMBUS Geometric Clot Extractor has demonstrated promising in vitro revascularization rates using fibrin-rich clot analogs. This study assessed the retrieval rate and composition of clot using NIMBUS in a clinical setting.

METHODS

This retrospective study included patients who underwent MT with NIMBUS at two high-volume stroke centers between December 2019 and May 2021. NIMBUS was used for clots deemed challenging to remove at the interventionalist's discretion. At one of the centers, per pass clot was collected for histological analysis by an independent lab.

RESULTS

A total of 37 patients (mean age 76.87 ± 11.73 years; 18 female; mean time from stroke onset 11.70 ± 6.41 h) were included. NIMBUS was used as first and second-line device in 5 and 32 patients, respectively. The main reason for using NIMBUS (32/37) was the failure of standard MT techniques after a mean 2.86 ± 1.48 number of passes. Substantial reperfusion (mTICI ≥2b) was achieved in 29/37 patients (78.4%) with a mean of 1.81 ± 1.00 NIMBUS passes (mean 4.68 ± 1.68 passes with all devices), and NIMBUS was the final device used in 79.3% (23/29) of those cases. Clot specimens from 18 cases underwent composition analysis. Fibrin and platelets represented 31.4 ± 13.7% and 28.8 ± 18.8% of clot components; 34.4 ± 19.5% were red blood cells.

CONCLUSIONS

In this series, NIMBUS was effective in removing tough clots rich in fibrin and platelets in challenging real-world situations.

Association of Intravenous Thrombolysis with Delayed Reperfusion After Incomplete Mechanical Thrombectomy

PURPOSE

Treatment of distal vessel occlusions causing incomplete reperfusion after mechanical thrombectomy (MT) is debated. We hypothesized that pretreatment with intravenous thrombolysis (IVT) may facilitate delayed reperfusion (DR) of residual vessel occlusions causing incomplete reperfusion after MT.

METHODS

Retrospective analysis of patients with incomplete reperfusion after MT, defined as extended thrombolysis in cerebral infarction (eTICI) 2a-2c, and available perfusion follow-up imaging at 24 ± 12 h after MT. DR was defined as absence of any perfusion deficit on time-sensitive perfusion maps, indicating the absence of any residual occlusion. The association of IVT with the occurrence of DR was evaluated using a logistic regression analysis adjusted for confounders. Sensitivity analyses based on IVT timing (time between IVT start and the occurrence incomplete reperfusion following MT) were performed.

RESULTS

In 368 included patients (median age 73.7 years, 51.1% female), DR occurred in 225 (61.1%). Atrial fibrillation, higher eTICI grade, better collateral status and longer intervention-to-follow-up time were all associated with DR. IVT did not show an association with the occurrence of DR (aOR 0.80, 95% CI 0.44-1.46, even in time-sensitive strata, aOR 2.28 [95% CI 0.65-9.23] and aOR 1.53 [95% CI 0.52-4.73] for IVT to incomplete reperfusion following MT timing <80 and <100 min, respectively).

CONCLUSION

A DR occurred in 60% of patients with incomplete MT at ~24 h and did not seem to occur more often in patients receiving pretreatment IVT. Further research on potential associations of IVT and DR after MT is required.

Direct Mechanical Thrombectomy vs. Bridging Therapy in Stroke Patients in A “Stroke Belt” Region of Southern Europe

The aim of this 4-year observational study is to analyze the outcomes of stroke patients treated with direct mechanical thrombectomy (dMT) compared to bridging therapy (BT) (intravenous thrombolysis [IVT] + BT) based on 3-month outcomes, in real clinical practice in the "Stroke Belt" of Southern Europe. In total, 300 patients were included (41.3% dMT and 58.6% BT). The frequency of direct referral to the stroke center was similar in the dMT and BT group, whereas the time from onset to groin was longer in the BT group (median 210 [IQR 160–303] vs. 399 [IQR 225–675], p = 0.001). Successful recanalization (TICI 2b-3) and hemorrhagic transformation were similar in both groups. The BT group more frequently showed excellent outcomes at 3 months (32.4% vs. 15.4%, p = 0.004). Multivariate analysis showed that BT was independently associated with excellent outcomes (OR 2.7. 95% CI,1.2–5.9, p = 0.02) and lower mortality (OR 0.36. 95% CI 0.16–0.82, p = 015). Conclusions: Compared with dMT, BT was associated with excellent functional outcomes and lower 3-month mortality in this real-world clinical practice study conducted in a region belonging to the “Stroke Belt” of Southern Europe. Given the disparity of results on the benefit of BT in the current evidence, it is of vital importance to analyze the convenience of its use in each health area.

Comparative efficacy and safety of tenecteplase and alteplase in acute ischemic stroke: A pairwise and network meta-analysis of randomized controlled trials

BACKGROUND

Studies on tenecteplase have been yielding mixed results for several important outcomes at different doses, thus hampering objective guideline recommendations in acute ischemic stroke management. This meta-analysis stratifies doses in order to refine our interpretation of outcomes and quantify the benefits and harms of tenecteplase at different doses.

METHODS

PubMed/MEDLINE, the Cochrane Library, and reference lists of the included articles were systematically searched. Several efficacy and safety outcomes were pooled and reported as risk ratios (RRs) with 95% confidence intervals (CIs). Network meta-analysis was used to find the optimal dose of tenecteplase. Meta-regression was run to investigate the impact of baseline NIHSS scores on functional outcomes and mortality.

RESULTS

Ten randomized controlled trials with a total of 4140 patients were included. 2166 (52.32%) patients were enrolled in the tenecteplase group and 1974 (47.68%) in the alteplase group. Tenecteplase at 0.25 mg/kg dose demonstrated significant improvement in excellent functional outcome at 3 months (RR 1.14, 95% CI 1.04-1.26), and early neurological improvement (RR 1.53, 95% CI 1.03-2.26). There was no statistically significant difference between tenecteplase and alteplase in terms of good functional outcome, intracerebral hemorrhage (ICH), symptomatic intracerebral hemorrhage (sICH), and 90-day mortality at any dose. Meta-regression demonstrated superior tenecteplase efficacy with increasing stroke severity, however, the results were statistically nonsignificant.

CONCLUSIONS

Tenecteplase at 0.25 mg/kg dose is more efficacious and at least as safe as alteplase for stroke thrombolysis. Newer analyses need to focus on direct comparison of tenecteplase doses and whether tenecteplase is efficacious at longer needle times.

Mechanical thrombectomy alone versus with thrombolysis for ischemic stroke: A meta-analysis of randomized trials

INTRODUCTION

Mechanical thrombectomy (MT) is the standard of care in eligible patients presenting with acute ischemic stroke (AIS). The question of whether intravenous thrombolysis (IVT) improves outcomes in conjunction with MT remains unanswered. We performed a systematic review and meta-analysis of published randomized controlled trials (RCT) to explore outcomes of MT with and without IVT.

METHODS

Following the PRISMA guidelines, a systematic literature review of the English language literature was conducted using PubMed, Embase, Web of science, and Scopus. Outcomes of interest included 90-day modified Rankin Scale (mRS) 0-2, thrombolysis in cerebral infarction (TICI) score 2b-3, symptomatic intracranial hemorrhage (sICH), distal embolization, and mortality. We calculated pooled risk ratios (RRs) and their corresponding 95% confidence intervals (CI).

RESULTS

Six RCTs with 2334 patients compared outcomes of patients treated with MT alone and MT with IVT. Both treatments resulted in comparable rates of mRS 0-2 (RR = 0.96, 95% CI = 0.88-1.04; p-value = 0.282), sICH (RR = 0.80, 95% CI = 0.55-1.17; p-value = 0.253), mortality at 90-days (RR = 1.06, 95% CI = 0.88-1.28; p-value = 0.529), and distal embolization (RR = 1.10, 95% CI = 0.79-1.52; p-value = 0.572). MT alone was associated with a lower rate of TICI 2b-3 compared to MT with IVT (RR = 0.96, 95% CI = 0.93-0.99; p-value = 0.006).

CONCLUSIONS

In this meta-analysis of six RCTs, MT alone was comparable to MT plus IVT for mRS 0-2, sICH, mortality, and distal embolization; however, MT alone resulted in lower rates of TICI 2b-3. Further trials are needed to determine which patient populations benefit from MT plus IVT and to increase the power of future meta-analyses.

Time-to-care metrics in patients with interhospital transfer for mechanical thrombectomy in north-east Germany: Primary telestroke centers in rural areas vs. primary stroke centers in a metropolitan area

Background

Mechanical thrombectomy (MT) is highly effective in large vessel occlusion (LVO) stroke. In north-east Germany, many rural hospitals do not have continuous neurological expertise onsite and secondary transport to MT capable comprehensive stroke centers (CSC) is necessary. In metropolitan areas, small hospitals often have neurology departments, but cannot perform MT. Thus, interhospital transport to CSCs is also required. Here, we compare time-to-care metrics and outcomes in patients receiving MT after interhospital transfer from primary stroke centers (PCSs) to CSCs in rural vs. metropolitan areas.

Methods

Patients from ten rural telestroke centers (RTCs) and nine CSCs participated in this study under the quality assurance registry for thrombectomies of the Acute Neurological care in North-east Germany with TeleMedicine (ANNOTeM) telestroke network. For the metropolitan area, we included patients admitted to 13 hospitals without thrombectomy capabilities (metropolitan primary stroke centers, MPSCs) and transferred to two CSCs. We compared groups regarding baseline variables, time-to-care metrics, clinical, and technical outcomes.

Results

Between October 2018 and June 2022, 50 patients were transferred from RTCs within the ANNOTeM network and 42 from MPSCs within the Berlin metropolitan area. RTC patients were older (77 vs. 72 yrs, p = 0.05) and had more severe strokes (NIHSS 17 vs. 10 pts., p < 0.01). In patients with intravenous thrombolysis (IVT; 34.0 and 40.5%, respectively), time from arrival at the primary stroke center to start of IVT was longer in RTCs (65 vs. 37 min, p < 0.01). However, RTC patients significantly quicker underwent groin puncture at CSCs (door-to-groin time: 42 vs. 60 min, p < 0.01). Despite longer transport distances from RTCs to CSCs (55 vs. 22 km, p < 0.001), there was no significant difference of times between arrival at the PSC and groin puncture (210 vs. 208 min, p = 0.96). In adjusted analyses, there was no significant difference in clinical and technical outcomes.

Conclusion

Despite considerable differences in the setting of stroke treatment in rural and metropolitan areas, overall time-to-care metrics were similar. Targets of process improvement should be door-to-needle times in RTCs, transfer organization, and door-to-groin times in CSCs wherever such process times are above best-practice models.

Endovascular thrombectomy with or without intravenous alteplase in acute stroke: a systematic review and meta-analysis of randomized clinical trials

BACKGROUND AND PURPOSE

This study investigated clinical outcomes after direct endovascular thrombectomy (EVT) compared to bridging therapy (EVT with prior intravenous alteplase) in acute stroke within 4.5 h after onset.

METHODS

PubMed and Embase were searched for eligible randomized controlled trials. The primary outcome was the rates of neurological functional independence defined as modified Rankin scale score 0-2 at 90 days, whose non-inferiority margin was set at - 15%, - 10%, - 6.5%, - 5%, and - 1.3% for its risk difference (RD).

RESULTS

We included six studies enrolling 2334 participants. The crude cumulative rates of functional independence were 49.0% with direct EVT vs 50.9% with bridging therapy, without significant difference (Odd ratio [OR] = 0.93, 95% confidence interval [CI] 0.79-1.09) between two groups, where the pooled RD was - 2% (95% CI - 6 to 2%) whose lower 95% CI bound fell within non-inferiority margins of - 15%, - 10%, -6.5%, but not - 5% and - 1.3%. Between the two groups, no significant difference was found in excellent function rate (30.2% vs 30.6%, OR = 0.99, 95% CI 0.82-1.18) with RD of 0% (95% CI - 3 to 4%), mortality rate (16.0% vs 15.0%, OR = 1.08, 95% CI 0.86-1.35) with RD of 1% (95% CI - 2 to 4%), and symptomatic intracranial hemorrhage rate (4.3% vs 5.0%, OR = 0.86, 95% CI 0.58-1.27) with RD of 0% (95% CI - 2 to 1%).

CONCLUSIONS

No statistical difference was found in functional and safety outcomes between direct EVT and bridging therapy groups in acute stroke within 4.5 h after symptom onset. EVT alone was non-inferior to bridging therapy for several, but not the more stringent, non-inferiority margins.

Neuroprotective Effects of Conditioned Medium of Mesenchymal Stem Cells (MSC-CM) as a Therapy for Ischemic Stroke Recovery: A Systematic Review

It has been reported that the therapeutic potential of stem cells is mainly mediated by their paracrine factors. In order to identify the effects of conditioned medium of mesenchymal stem cells (MSC-CM) against stroke, a systematic review was conducted. We searched PubMed, Scopus, and ISI Web of Science databases for all available articles relevant to the effects of MSC-CM against the middle cerebral artery occlusion (MCAO) model of ischemic stroke until August 2022. The quality of the included studies was evaluated using The STAIR scale. During the systematic search, a total of 356 published articles were found. A total of 15 datasets were included following screening for eligibility. The type of cerebral ischemia was the MCAO model and CM was obtained from MSCs. The results showed that the therapeutic time window can be considered a crucial factor when researchers use MSC-CM for stroke therapy. In addition, MSC-CM therapy contributes to functional recovery and reduces infarct volume after stroke by targeting different cellular signaling pathways. Our findings showed that MSC-CM therapy has the ability to improve functional recovery and attenuate brain infarct volume after ischemic stroke in preclinical studies. We hope our study accelerates needed progress towards clinical trials.

Mild and moderate cardioembolic stroke patients may benefit more from direct mechanical thrombectomy than bridging therapy: A subgroup analysis of a randomized clinical trial (DIRECT-MT)

Background

The benefit of intravenous alteplase before endovascular thrombectomy is unclear in patients with acute cardioembolic stroke.

Methods

We collected cardioembolic (CE) stroke patient data from the multicentre randomized clinical trial of Direct Intra-arterial Thrombectomy to Revascularize Acute Ischaemic Stroke Patients with Large Vessel Occlusion Efficiently in Chinese Tertiary Hospitals (DIRECT-MT). The primary outcome was the 90-day modified Rankin Scale (mRS) score. Five subgroups of cardioembolic stroke patients were analyzed. A multivariable ordinal logistic regression analysis analyzed the difference in the primary outcome between the direct mechanical thrombectomy (MT) and bridging therapy groups. An interaction term was entered into the model to test for subgroup interaction. The DIRECT-MT trial is registered with clinicaltrials.gov Identifier: NCT03469206.

Results

A total of 290 CE stroke patients from the DIRECT-MT trial were enrolled in this study: 146 patients in the direct MT group and 144 patients in the bridging therapy group. No difference between the two treatment groups in the primary outcome was found (adjusted common odds ratio, 1.218; 95% confidence interval, 0.806 to 1.841; P = 0.34). In the subgroup analysis, CE stroke patients with an NIHSS ≤ 15 in the direct MT group were associated with better outcomes (47 vs. 53, acOR, 3.14 [1.497, 6.585]) and lower mortality (47 vs. 53, aOR, 0.16 [0.026, 0.986]) than those in the bridging therapy group, while there were no significant differences between the two treatment groups in the outcome and mortality of CE stroke patients with an NIHSS >15.

Conclusion

Mild and moderate cardioembolic stroke patients may benefit more from direct mechanical thrombectomy than bridging therapy. This need to be confirmed by further prospective studies in a larger number of patients.

Predictors and clinical outcomes of post-coronary artery bypass grafting cerebrovascular strokes

Background

Despite the improved medical and surgical managements, still there is a significant risk of developing acute cerebrovascular strokes after coronary artery bypass grafting (CABG). Our objectives were to study the immediate and long-term outcomes after CABG and to identify the possible predictors of post-CABG strokes.

Results

Between January 2016 and August 2020, 410 adult patients, mostly males (82.2%), were retrospectively enrolled after CABG. Acute postoperative strokes occurred in 31 (7.5%) patients; of them, 30 (96.8%) patients had ischemic stroke, while 1 (3.2%) had hemorrhagic stroke. Mechanical thrombectomy was done in two cases. The patients who developed acute cerebral stroke had significantly higher admission (p = 0.02) and follow-up (p < 0.001) SOFA scores, higher arterial blood lactate level (p < 0.001), longer hospitalization (p < 0.001) and more hospital mortality (p < 0.001) compared with the patients who did not develop stroke. Kaplan–Meier curves for 5-year mortality showed increased risk in those patients with postoperative stroke (HR: 23.03; 95% CI: 6.10–86.92, p < 0.001). After multivariate regression, the predictors of early postoperative stroke were carotid artery stenosis (CAS), postoperative atrial fibrillation, cardiopulmonary bypass time, prior cerebral stroke, admission SOFA score and chronic kidney disease (CKD). The predictors of late cerebrovascular stroke were CAS, combined CABG and valve surgery, CKD, atrial fibrillation, prior stroke and HbA1c.

Conclusions

The development of post-CABG acute cerebrovascular stroke is associated with longer hospitalization, multiple morbidities and increased mortality. Careful assessment and management of risk factors especially atrial fibrillation and carotid artery stenosis should be implemented to decrease this substantial complication after CABG.

Selective Cerebrospinal Fluid Hypothermia: Bioengineering Development and In Vivo Study of an Intraventricular Cooling Device (V-COOL)

Hypothermia is a promising therapeutic strategy for severe vasospasm and other types of non-thrombotic cerebral ischemia, but its clinical application is limited by significant systemic side effects. We aimed to develop an intraventricular device for the controlled cooling of the cerebrospinal fluid, to produce a targeted hypothermia in the affected cerebral hemisphere with a minimal effect on systemic temperature. An intraventricular cooling device (acronym: V-COOL) was developed by in silico modelling, in vitro testing, and in vivo proof-of-concept application in healthy Wistar rats (n = 42). Cerebral cortical temperature, rectal temperature, and intracranial pressure were monitored at increasing flow rate (0.2 to 0.8 mL/min) and duration of application (10 to 60 min). Survival, neurological outcome, and MRI volumetric analysis of the ventricular system were assessed during the first 24 h. The V-COOL prototyping was designed to minimize extra-cranial heat transfer and intra-cranial pressure load. In vivo application of the V-COOL device produced a flow rate-dependent decrease in cerebral cortical temperature, without affecting systemic temperature. The target degree of cerebral cooling (- 3.0 °C) was obtained in 4.48 min at the flow rate of 0.4 mL/min, without significant changes in intracranial pressure. Survival and neurological outcome at 24 h showed no significant difference compared to sham-treated rats. MRI study showed a transient dilation of the ventricular system (+ 38%) in a subset of animals. The V-COOL technology provides an effective, rapid, selective, and safe cerebral cooling to a clinically relevant degree of - 3.0 °C.

Effect of Admission Hyperglycemia on Safety and Efficacy of Intravenous Alteplase Before Thrombectomy in Ischemic Stroke: Post-hoc Analysis of the DIRECT-MT trial

Hyperglycemia is associated with decreased recanalization probability and increased risk of hemorrhagic complications for stroke patients treated with intravenous alteplase. However, whether hyperglycemia modifies alteplase treatment effect on clinical outcome in patients with large vessel occlusion stroke undergoing endovascular thrombectomy is uncertain. We conducted this study to determine a possible interaction effect between admission hyperglycemia and intravenous alteplase prior to thrombectomy in patients with large vessel occlusion stroke. In this post-hoc analysis of a randomized trial (DIRECT-MT) comparing intravenous alteplase before endovascular treatment vs. endovascular treatment only, 649 with available baseline glucose measurements were included. The treatment-by-admission hyperglycemia (defined as plasma glucose levels ≥ 7.8 mmol/L [140 mg/dL]) interaction was assessed using logistic regression models. As a result, among 649 patients included, 224 (34.5%) were hyperglycemic at admission. There was evidence of alteplase treatment effect modification by hyperglycemia (Pinteraction = 0.025). In patients without hyperglycemia, combination therapy was associated with better outcomes compared to mechanical thrombectomy alone (adjusted common odd ratio [acOR] 1.46, 95% CI [1.04-2.07]), but not in hyperglycemic patients (acOR 0.74, 95% CI [0.46-1.20]). Combination therapy led to an absolute increase of 6% excellent outcome (mRS 0-1) in non-hyperglycemic patients (aOR 1.71, 95% CI [1.05-2.79]), but resulted in a 12.3% absolute decrease (aOR 0.42 [95% CI, 0.19-0.95] in hyperglycemic patients (Pinteraction = 0.003). In conclusion, for large vessel occlusion patients directly presenting to a thrombectomy-capable hospital, hyperglycemia modified combination treatment effect on clinical outcome. Combination therapy was beneficial in patients without hyperglycemia, while thrombectomy alone may be preferred in hyperglycemic patients. Further studies are needed to confirm this result.Trial Registration Information: clinicaltrials.gov Identifier: NCT03469206.

Endovascular thrombectomy or bridging therapy in minor ischemic stroke with large vessel occlusion

BACKGROUND

Whether direct endovascular thrombectomy (EVT) is non-inferior to bridging therapy (intravenous thrombolysis [IVT] followed by EVT) in minor acute ischemic stroke due to large vessel occlusions (AIS-LVO) is not clear. Therefore, this study aimed to assess whether direct EVT is non-inferior to bridging therapy in minor AIS-LVO.

METHODS

903 patients with acute ischemic stroke due to large vessel occlusion and National Institutes of Health Stroke Scale (NIHSS) score <6 receiving EVT treatment were enrolled at Bigdata Observatory Platform for Stroke of China in China from January 1, 2019, to December 31, 2020, with final follow-up on March 31, 2021. The primary efficacy endpoint was a favorable outcome defined as a modified Rankin Scale score of 0 to 2 at three months. In addition, there were three prespecified secondary efficacy endpoints, including symptomatic intracerebral hemorrhage (ICH), in-hospital mortality, and mortality by month 3.

RESULTS

A total of 662 patients treated with direct EVT (age 65.9 ± 10.5 years, 71.5 % male, NIHSS score 2.4 [standard deviation {SD}. 1.8]) were compared to 241 bridging-treated patients (age 65.7 ± 10.8, 75.9 % female, NIHSS score 2.5 [1.8]). The rate of symptomatic ICH in the EVT group was lower than in the bridging group (4.2 % vs. 8.3 %; P = 0.02). The in-hospital mortality was not different between the two groups (EVT vs. bridging group: adjusted hazard ratio {HR}, 0.9 [95 % confidence interval {CI}, 0.5 to 1.9]; P = 0.93). There was no significant difference in 3-month poor functional outcome rate (EVT vs. bridging group: 17.1 % vs. 16.2 % [absolute difference, 0.9 % {95 % CI, -0.8 % to 2.4 %}, P = 0.75; adjusted hazard ratio {HR}, 1.0 {95 % CI, 0.6 to 1.7}, P = 0.83]) and mortality rate (13.0 % vs. 11.2 % [absolute difference, 1.5 % {95 % CI, -3.9 % to 6.8 %}, P = 0.47; adjusted HR, 1.1 {95 % CI, 0.8 to 1.9}, P = 0.55]) between those two groups.

CONCLUSION

Among patients with minor AIS-LVO, direct EVT, compared with bridging therapy, met the prespecified statistical threshold for noninferiority for the 3-month prognosis.

Anti-seizure medication treatment and outcomes in acute ischemic stroke patients undergoing continuous EEG monitoring

OBJECTIVES

To determine the association of anti-seizure medication (ASM) treatment with outcomes in acute ischemic stroke (AIS) patients undergoing continuous electroencephalography (cEEG).

METHODS

Retrospective analysis of AIS patients admitted between 2012 and 2019. The following are the inclusion criteria: age ≥ 18 years and ≥ 16 h of cEEG within the first 7 days of admission. ASM treatment exposure was defined as > 48 h of treatment after the first 24 h of cEEG. The primary outcome measure was 90-day mortality, and the secondary outcome was 90-day functional recovery (Modified Ranking Scale 0-3). Propensity scores were used to adjust for baseline covariates and presence of epileptiform abnormalities (seizures, periodic and rhythmic patterns).

RESULTS

One hundred thirteen patients met the inclusion criteria; 39 (34.5%) were exposed to ASM. ASM treatment was not associated with 90-day mortality (propensity adjusted HR 1.0 [0.31-3.27], p = 0.999) or functional outcomes (adjusted HR 0.99 [0.32-3.02], p = 0.989), compared to no treatment.

CONCLUSIONS

In our study, ASM treatment in AIS patients with cEEG abnormalities was not significantly associated with a change in 90-day mortality and functional recovery. Larger comparative effectiveness studies are indicated to identify which acute ischemic stroke patients with cEEG abnormalities benefit most from ASM treatment.

3D transcranial ultrasound localization microscopy for discrimination between ischemic and hemorrhagic stroke in early phase

Early diagnosis is a critical part of the emergency care of cerebral hemorrhages and ischemia. A rapid and accurate diagnosis of strokes reduces the delays to appropriate treatments and a better functional recovery. Currently, CTscan and MRI are the gold standards with constraints of accessibility, availability, and possibly some contraindications. The development of Ultrasound Localization Microscopy (ULM) has enabled new perspectives to conventional transcranial ultrasound imaging with increased sensitivity, penetration depth, and resolution. The possibility of volumetric imaging has increased the field-of-view and provided a more precise description of the microvascularisation. In this study, rats (n = 9) were subjected to thromboembolic ischemic stroke or intracerebral hemorrhages prior to volumetric ULM at the early phases after onsets. Although the volumetric ULM performed in the early phase of ischemic stroke revealed a large hypoperfused area in the cortical area of the occluded artery, it showed a more diffused hypoperfusion in the hemorrhagic model. Respective computations of a Microvascular Diffusion Index highlighted different patterns of perfusion loss during the first 24 h of these two strokes’ subtypes. Our study provides the first proof that this methodology should allow early discrimination between ischemic and hemorrhagic stroke with a potential toward diagnosis and monitoring in clinic.

Burden of stroke in North Africa and Middle East, 1990 to 2019: a systematic analysis for the global burden of disease study 2019

BACKGROUND

While several studies investigated the epidemiology and burden of stroke in the North Africa and Middle East region, no study has comprehensively evaluated the age-standardized attributable burden to all stroke subtypes and their risk factors yet.

OBJECTIVE

The aim of the present study is to explore the regional distribution of the burden of stroke, including ischemic stroke, subarachnoid hemorrhage, and intracerebral hemorrhage, and the attributable burden to its risk factors in 2019 among the 21 countries of North Africa and Middle East super-region.

METHODS

The data of the Global Burden of Disease Study (GBD) 2019 on stroke incidence, prevalence, death, disability-adjusted life years (DALYs), years of life lost (YLLs), years lived with disability (YLDs) rates, and attributed deaths, DALYs, YLLs, and YLDs to stroke risk factors were used for the present study.

RESULTS

The age-standardized deaths, DALYs, and YLLs rates were diminished statistically significant by 27.8, 32.0, and 35.1% from 1990 to 2019, respectively. Attributed deaths, DALYs, and YLLs to stroke risk factors, including high systolic blood pressure, high body-mass index, and high fasting plasma glucose shrank statistically significant by 24.9, 25.8, and 28.8%, respectively.

CONCLUSION

While the age-standardized stroke burden has reduced during these 30 years, it is still a concerning issue due to its increased burden in all-age numbers. Well-developed primary prevention, timely diagnosis and management of the stroke and its risk factors might be appreciated for further decreasing the burden of stroke and its risk factors and reaching Sustainable Development Goal 3.4 target for reducing premature mortality from non-communicable diseases.

Thrombectomy alone versus intravenous alteplase plus thrombectomy in patients with stroke: an open-label, blinded-outcome, randomised non-inferiority trial

BACKGROUND

Whether thrombectomy alone is equally as effective as intravenous alteplase plus thrombectomy remains controversial. We aimed to determine whether thrombectomy alone would be non-inferior to intravenous alteplase plus thrombectomy in patients presenting with acute ischaemic stroke.

METHODS

In this multicentre, randomised, open-label, blinded-outcome trial in Europe and Canada, we recruited patients with stroke due to large vessel occlusion confirmed with CT or magnetic resonance angiography admitted to endovascular centres. Patients were randomly assigned (1:1) via a centralised web server using a deterministic minimisation method to receive stent-retriever thrombectomy alone or intravenous alteplase plus stent-retriever thrombectomy. In both groups, thrombectomy was initiated as fast as possible with any commercially available Solitaire stent-retriever revascularisation device (Medtronic, Irvine, CA, USA). In the combined treatment group, intravenous alteplase (0·9 mg/kg bodyweight, maximum dose 90 mg per patient) was administered as early as possible after randomisation for 60 min with 10% of the calculated dose given as an initial bolus. Personnel assessing the primary outcome were masked to group allocation; patients and treating physicians were not. The primary binary outcome was a score of 2 or less on the modified Rankin scale at 90 days. We assessed the non-inferiority of thrombectomy alone versus intravenous alteplase plus thrombectomy in all randomly assigned and consenting patients using the one-sided lower 95% confidence limit of the Mantel-Haenszel risk difference, with a prespecified non-inferiority margin of 12%. The main safety endpoint was symptomatic intracranial haemorrhage assessed in all randomly assigned and consenting participants. This trial is registered with ClinicalTrials.gov, NCT03192332, and is closed to new participants.

FINDINGS

Between Nov 29, 2017, and May 7, 2021, 5215 patients were screened and 423 were randomly assigned, of whom 408 (201 thrombectomy alone, 207 intravenous alteplase plus thrombectomy) were included in the primary efficacy analysis. A modified Rankin scale score of 0-2 at 90 days was reached by 114 (57%) of 201 patients assigned to thrombectomy alone and 135 (65%) of 207 patients assigned to intravenous alteplase plus thrombectomy (adjusted risk difference -7·3%, 95% CI -16·6 to 2·1, lower limit of one-sided 95% CI -15·1%, crossing the non-inferiority margin of -12%). Symptomatic intracranial haemorrhage occurred in five (2%) of 201 patients undergoing thrombectomy alone and seven (3%) of 202 patients receiving intravenous alteplase plus thrombectomy (risk difference -1·0%, 95% CI -4·8 to 2·7). Successful reperfusion was less common in patients assigned to thrombectomy alone (182 [91%] of 201 vs 199 [96%] of 207, risk difference -5·1%, 95% CI -10·2 to 0·0, p=0·047).

INTERPRETATION

Thrombectomy alone was not shown to be non-inferior to intravenous alteplase plus thrombectomy and resulted in decreased reperfusion rates. These results do not support omitting intravenous alteplase before thrombectomy in eligible patients.

FUNDING

Medtronic and University Hospital Bern.

Lactobacillus Plantarum-derived extracellular vesicles protect against ischemic brain injury via the microRNA-101a-3p/c-Fos/TGF-β axis

Currently, the reported source of extracellular vesicles (EVs) for the treatment of ischemic stroke（IS）is limited to mammals. Moreover, these EVs are restricted to clinical translation by the high cost of cell culture. In this respect, Lactobacillus Plantarum culture is advantaged by low cost and high yield. However, it is poorly understood whether Lactobacillus Plantarum-derived EVs (LEVs) are applicable for the treatment of IS. Here, our results demonstrated that LEVs reduced apoptosis in ischemic neuron both in vivo and in vitro. As revealed by high-throughput sequencing, miR-101a-3p expression was significantly elevated by LEV treatment in OGD/R-induced neurons, as confirmed in the tMCAO mice treated with LEVs. Mechanistically, c-Fos was directly targeted by miR-101a-3p. In addition, c-Fos determined ischemia-induced neuron apoptosis in vivo and in vitro through the TGF-β1 pathway, miR-101a-3p inhibition aggravated ischemia-induced neuron apoptosis in vitro and in vivo, and miR-101a-3p overexpression produced the opposite results. Hsa-miR-101-3p was downregulated in the plasma of patients with IS but upregulated in the patients with neurological recovery after rt-PA intravenous thrombolysis. In conclusion, Our results demonstrated for the first time that LEVs might inhibit neuron apoptosis via the miR-101a-3p/c-Fos/TGF-β axis, and has-miR-101-3p is a potential marker of neurological recovery in IS patients.

Safety and Efficacy of Intravenous Alteplase before Endovascular Thrombectomy: A Pooled Analysis with Focus on the Elderly

Current guidelines advocate intravenous thrombolysis (IVT) prior to endovascular thrombectomy (EVT) for all patients with acute ischemic stroke (AIS) due to large vessel occlusion (LVO). We evaluated outcomes with and without IVT pretreatment. Our institutional protocols allow AIS patients presenting early (<4 h from onset or last seen normal) who have an Alberta Stroke Program Early CT Score (ASPECTS) ≥6 to undergo EVT without IVT pretreatment if the endovascular team is in the hospital (direct EVT). Rates of recanalization and hemorrhagic transformation (HT) and neurological outcomes were retrospectively compared in consecutive patients undergoing IVT+EVT vs. direct EVT with subanalyses in those ≥80 years and ≥85 years. In the overall cohort (IVT+EVT = 147, direct EVT = 162), and in subsets of patients ≥80 years (IVT+EVT = 51, direct EVT = 50) and ≥85 years (IVT+EVT = 19, direct EVT = 32), the IVT+EVT cohort and the direct EVT group had similar baseline characteristics, underwent EVT after a comparable interval from symptom onset, and reached similar rates of target vessel recanalization. No differences were observed in the HT frequency, or in disability at discharge or after 90 days. Patients receiving direct EVT underwent more stenting of the carotid artery due to stenosis during the EVT procedure (22% vs. 6%, p = 0.001). Direct EVT and IVT+EVT had comparable neurological outcomes in the overall cohort and in the subgroups of patients ≥80 and ≥85 years, suggesting that direct EVT should be considered in patients with an elevated risk for HT.

Endovascular thrombectomy with or without intravenous alteplase for acute ischemic stroke due to large vessel occlusion: a systematic review and meta-analysis of randomized trials

BACKGROUND

Among patients who had an ischaemic stroke presenting directly to a stroke centre where endovascular thrombectomy (EVT) is immediately available, there is uncertainty regarding the role of intravenous thrombolysis agents before or concurrently with EVT. To support a rapid guideline, we conducted a systematic review and meta-analysis to examine the impact of EVT alone versus EVT with intravenous alteplase in patients who had an acute ischaemic stroke due to large vessel occlusion.

METHODS

In November 2021, we searched MEDLINE, Embase, PubMed, Cochrane, Web of Science, clincialtrials.gov and the ISRCTN registry for randomised controlled trials (RCTs) comparing EVT alone versus EVT with alteplase for acute ischaemic stroke. We conducted meta-analyses using fixed effects models and assessed the certainty of evidence using the GRADE approach.

RESULTS

In total 6 RCTs including 2334 participants were eligible. Low certainty evidence suggests that, compared with EVT and alteplase, there is possibly a small decrease in the proportion of patients independent with EVT alone (risk ratio (RR) 0.97, 95% CI 0.89 to 1.05; risk difference (RD) -1.5%; 95% CI -5.4% to 2.5%), and possibly a small increase in mortality with EVT alone (RR 1.07, 95% CI 0.88 to 1.29; RD 1.2%, 95% CI -2.0% to 4.9%) . Moderate certainty evidence suggests that there is probably a small decrease in symptomatic intracranial haemorrhage (sICH) with EVT alone (RR 0.75, 95% CI 0.52 to 1.07; RD -1.0%; 95%CI -1.8% to 0.27%).

CONCLUSIONS

Low certainty evidence suggests that there is possibly a small decrease in the proportion of patients that achieve functional independence and a small increase in mortality with EVT alone. Moderate certainty evidence suggests that there is probably a small decrease in sICH with EVT alone. The accompanying guideline provides contextualised guidance based on this body of evidence.

PROSPERO REGISTRATION NUMBER

CRD42021249873.

Efficacy and safety of endovascular treatment with or without intravenous alteplase in acute anterior circulation large vessel occlusion stroke: a meta-analysis of randomized controlled trials

OBJECTIVE

The current meta-analysis aimed to investigate the efficacy and safety of direct endovascular treatment (EVT) and bridging therapy (EVT with prior intravenous thrombolysis (IVT)) in patients with acute anterior circulation large vessel occlusion (LVO) stroke.

METHODS

This meta-analysis followed PRISMA guidelines. Eligible RCTs were identified through a systemic search of electronic databases (PubMed, Ovid, Web of Science, and Cochrane Library) from the inception dates to January 10, 2022. The pooled analyses were performed using RevMan 5.3 software. The primary outcome was functional outcome on the modified Rankin Scale (mRS) (range 0 to 5) at 90 days. The secondary outcomes included successful reperfusion, intracranial hemorrhage, and mortality (mRS 6) within 90 days.

RESULTS

A total of 4 RCTs involving 1633 patients were finally included. Findings of pooled analyses indicated that neither the primary outcomes (no disability (mRS 0), no significant disability despite some symptoms (mRS 1), slight disability (mRS 2), moderate disability (mRS 3), moderately severe disability (mRS 4), severe disability (mRS 5), excellent outcome (mRS 0-1), functional independence outcome (mRS 0-2), and poor outcome (mRS 3-5)) nor the secondary outcomes (successful reperfusion, intracranial hemorrhage, and mortality) in the EVT groups were not statistically significant compared with the IVT plus EVT groups (P > 0.05). In addition, the outcomes of sensitivity analysis implied that the findings of meta-analysis were credible.

CONCLUSIONS

Among patients with acute ischemic stroke due to LVO of anterior circulation, EVT alone yielded efficacy and safety outcomes similar to IVT plus EVT.

Role of Intravenous Thrombolytics Prior to Endovascular Thrombectomy

Intravenous thrombolytics and endovascular thrombectomy for ischemic stroke have evolved in parallel. However, the best approach to combine these reperfusion therapies in patients eligible for both strategies remains uncertain. Initial randomized trials of endovascular thrombectomy included administration of intravenous thrombolytics to all eligible patients. However, whether that is of net benefit has been questioned and parallels drawn with treatment of ST-segment-elevation myocardial infarction, where intravenous thrombolytics are only given if first medical contact to percutaneous intervention is expected to be >90 minutes. Six randomized trials of a direct thrombectomy approach versus intravenous thrombolytics followed by endovascular thrombectomy have now reported their results. With exception of a minority of patients in one trial, the trials all used alteplase rather than potentially more effective tenecteplase. This review examines the current state of evidence and implications for clinical practice. Importantly, these trials only apply to patients who present to a hospital with immediate access to endovascular thrombectomy and are not relevant to patients who receive thrombolytic and are then transferred to an endovascular-capable hospital. Although 2 of the 6 randomized trials met their prespecified noninferiority margin, these margins were large compared with the absolute benefit of alteplase. Overall, functional outcome was similar, with slight trends favoring bridging thrombolytics and a significant increase in final reperfusion. Symptomatic hemorrhage was increased by ≈1.8% in the bridging group but death was nonsignificantly lower. The workflow in direct thrombectomy trials involved delaying thrombolytic administration until eligibility for thrombectomy and the trials was established and randomization completed. This reduced the time available for thrombolytics to occur prethrombectomy compared with standard practice. We conclude that, pending individual-patient data meta-analyses, intravenous thrombolytics retain an important role alongside endovascular thrombectomy. Further efforts to accelerate and enhance reperfusion with thrombolytics and perform individual patient-level pooled subgroup analyses are warranted.

Histological composition of retrieved emboli in acute ischemic stroke is independent of pre-thrombectomy alteplase use

BACKGROUND AND PURPOSE

Given recent evidence suggesting the clot composition may be associated with revascularization outcomes and stroke etiology, clot composition research has been a topic of growing interest. It is currently unclear what effect, if any, pre-thrombectomy thrombolysis has on clot composition. Understanding this association is important as it is a potential confounding variable in clot composition research. We retrospectively evaluated the composition of retrieved clots from ischemic stroke patients who did and did not receive pre-treatment tPA to study the effect of tPA on clot composition.

MATERIALS AND METHODS

Consecutive patients enrolled in the Stroke Thromboembolism Registry of Imaging and Pathology (STRIP) were included in this study. All patients underwent mechanical thrombectomy and retrieved clots were sent to a central core lab for processing. Histological analysis was performed using Martius Scarlett Blue (MSB) staining and area of the clot was also measured on the gross photos. Student's t test was used for continuous variables and chi-squared test for categorical variables.

RESULTS

A total of 1430 patients were included in this study. Mean age was 68.4±13.5 years. Overall rate of TICI 2c/3 was 67%. A total of 517 patients received tPA (36%) and 913 patients did not (64%). Mean RBC density for the tPA group was 42.97±22.62% compared to 42.80±23.18% for the non-tPA group (P=0.89). Mean WBC density for the tPA group was 3.74±2.60% compared to 3.42±2.21% for the non-tPA group (P=0.012). Mean fibrin density for the tPA group was 26.52±15.81% compared to 26.53±15.34% for the non-tPA group (P=0.98). Mean platelet density for the tPA group was 26.22±18.60% compared to 26.55±19.47% for the non-tPA group (P=0.75). tPA group also had significantly smaller clot area compared to non-tPA group.

CONCLUSIONS

Our study 1430 retrieved emboli and ischemic stroke patients shows no interaction between tPA administration and clot composition. These findings suggest that tPA does not result in any histological changes in clot composition.

J147 Reduces tPA-Induced Brain Hemorrhage in Acute Experimental Stroke in Rats

Background and purpose

J147, a novel neurotrophic compound, was originally developed to treat aging-associated neurological diseases. Based on the broad spectrum of cytoprotective effects exhibited by this compound, we investigated whether J147 has cerebroprotection for acute ischemic stroke and whether it can enhance the effectiveness of thrombolytic therapy with tissue plasminogen activator (tPA).

Methods

Rats were subjected to transient occlusion of the middle cerebral artery (tMCAO) by insertion of an intraluminal suture or embolic middle cerebral artery occlusion (eMCAO), and treated intravenously with J147 alone or in combination with tPA.

Results

We found that J147 treatment significantly reduced infarct volume when administered at 2 h after stroke onset in the tMCAO model, but had no effect in eMCAO without tPA. However, combination treatment with J147 plus tPA at 4 h after stroke onset significantly reduced infarct volume and neurological deficits at 72 h after stroke compared with saline or tPA alone groups in the eMCAO model. Importantly, the combination treatment significantly reduced delayed tPA-associated brain hemorrhage and secondary microvascular thrombosis. These protective effects were associated with J147-mediated inhibition of matrix metalloproteinase-9 (MMP9), 15-lipoxygenase-1, and plasminogen activator inhibitor (PAI) expression in the ischemic hemispheres (predominantly in ischemic cerebral endothelium). Moreover, the combination treatment significantly reduced circulating platelet activation and platelet-leukocyte aggregation compared with saline or tPA alone groups at 24 h after stroke, which might also contribute to reduced microvascular thrombosis and neuroinflammation (as demonstrated by reduced neutrophil brain infiltration and microglial activation).

Conclusion

Our results demonstrate that J147 treatment alone exerts cerebral cytoprotective effects in a suture model of acute ischemic stroke, while in an embolic stroke model co-administration of J147 with tPA reduces delayed tPA-induced intracerebral hemorrhage and confers cerebroprotection. These findings suggest that J147-tPA combination therapy could be a promising approach to improving the treatment of ischemic stroke.

Effect of baseline infarct size on endovascular thrombectomy with or without intravenous alteplase in stroke patients: a subgroup analysis of a randomized trial (DIRECT-MT)

BACKGROUND

DIRECT-MT showed that endovascular thrombectomy was non-inferior to thrombectomy preceded by intravenous alteplase with regard to functional outcome in patients with acute ischemic stroke. In this post-hoc analysis, we examined whether infarct size modified the effect of alteplase.

METHODS

All patients with baseline Alberta Stroke Program Early Computed Tomography Score (ASPECTS) grade were included. The primary outcome was the 90-day modified Rankin Scale (mRS) score. Multivariable ordinal logistic regression analysis was used to calculate the adjusted common odds ratio (OR) for better functional outcome based on the mRS for thrombectomy alone versus combination therapy. An interaction term was entered to test for an interaction with baseline ASPECTS subgroups: 0-4 versus 5-7 versus 8-10.

RESULTS

Of 649 patients, 323 (49.8%) were in the thrombectomy-alone group and 326 (50.2%) in the combination-therapy group. There was no significant treatment-by-trichotomized ASPECTS interaction with alteplase prior to endovascular treatment for the primary endpoint of ordinal mRS (p-value interaction term relative to ASPECTS 8-10: ASPECTS 0-4, p=0.386; ASPECTS 5-7, p=0.936). Adjusted common OR for improvement in the 90-day mRS with thrombectomy alone compared with combination therapy were 1.99 (95% confidence intervals, 0.72-5.46) for ASPECTS 0-4, 1.07 (0.62-1.86) for ASPECTS 5-7, and 1.03 (0.74-1.45) for ASPECTS 8-10. There was no significant difference in the safety outcomes between the two groups.

CONCLUSIONS

Baseline infarct size may not modify the effect of alteplase prior to endovascular thrombectomy with regard to favorable functional outcomes and adverse events.

Bridging Thrombolysis versus Direct Mechanical Thrombectomy in Stroke Due to Basilar Artery Occlusion

Background and Purpose

Mechanical thrombectomy (MT) is an effective treatment for patients with basilar artery occlusion (BAO) acute ischemic stroke. It remains unclear whether bridging intravenous thrombolysis (IVT) prior to MT confers any benefit. This study compared the outcomes of acute BAO patients who were treated with direct MT versus combined IVT plus MT.

Methods

This multicenter retrospective cohort study included patients who were treated for acute BAO from eight comprehensive stroke centers between January 2015 and December 2019. Patients received direct MT or combined bridging IVT plus MT. Primary outcome was favorable functional outcome defined as modified Rankin Scale 0–3 measured at 90 days. Secondary outcome measures included mortality and symptomatic intracranial hemorrhage (sICH).

Results

Among 322 patients, 127 (39.4%) patients underwent bridging IVT followed by MT and 195 (60.6%) underwent direct MT. The mean±standard deviation age was 67.5±14.1 years, 64.0% were male and median National Institutes of Health Stroke Scale was 16 (interquartile range, 8 to 25). At 90-day, the rate of favorable functional outcome was similar between the bridging IVT and direct MT groups (39.4% vs. 34.4%, P=0.361). On multivariable analyses, bridging IVT was not as Comorbidisociated with favorable functional outcome, mortality or sICH. In subgroup analyses, patients with underlying atherosclerosis treated with bridging IVT compared to direct MT had a higher rate of favorable functional outcome at 90 days (37.2% vs. 15.5%, P=0.013).

Conclusions

Functional outcomes were similar in BAO patients treated with bridging IVT versus direct MT. In the subgroup of patients with underlying large-artery atherosclerosis stroke mechanism, bridging IVT may potentially confer benefit and this warrants further investigation.

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.

Direct Endovascular Thrombectomy or With Prior Intravenous Thrombolysis for Acute Ischemic Stroke: A Meta-Analysis

Background and purpose: It is unclear whether endovascular thrombectomy alone compared with intravenous thrombolysis combination with endovascular thrombectomy can achieve similar neurological outcomes in patients with acute large vessel occlusion stroke. We aimed to perform a systematic review and meta-analysis of randomized controlled trials to compare endovascular thrombectomy alone or intravenous thrombolysis plus endovascular thrombectomy in this population.

Methods: We systematically searched PubMed, Embase, and ClinicalTrials.gov. We restricted our search to randomized clinical trials that examined the clinical outcomes of endovascular thrombectomy alone vs. intravenous thrombolysis plus endovascular thrombectomy. The Cochrane risk of bias tool was used to assess study quality. Random-effects meta-analyses were used for evaluating all outcomes.

Results: Total three randomized controlled trials with 1,092 individuals enrolled were included in the meta-analysis, including 543 (49.7%) who received endovascular thrombectomy alone and 549 (50.3%) who received intravenous thrombolysis plus endovascular thrombectomy. The primary outcome of 90-day functional independence (modified Rankin scale (mRS) score ≤ 2) was 44.6% (242/543) in the endovascular thrombectomy alone group vs. 42.8% (235/549) in the alteplase with endovascular thrombectomy group (odds ratio (OR), 1.08 [95% CI, 0.85–1.38]; P = 0.0539). Among pre-specified secondary outcomes, no significant between-group differences were found in excellent outcome (mRS score ≤ 1) (OR, 1.12 [95% CI, 0.85–1.47]; P = 0.418), mortality at 90 days (OR, 0.93 [95% CI, 0.68–1.29]; P = 0.673), successful reperfusion (thrombolysis in cerebral infarction 2b-3) (OR, 0.75 [95% CI, 0.54–1.05]; P = 0.099), and symptomatic intracranial hemorrhage (OR, 0.72 [95% CI, 0.45–1.15]; P = 0.171).

Conclusions: Among patients with acute ischemic stroke in the anterior circulation within 4.5 h from the onset, endovascular thrombectomy alone was non-inferior to combined intravenous thrombolysis and endovascular thrombectomy.