Association of Endovascular Thrombectomy vs Medical Management With Functional and Safety Outcomes in Patients Treated Beyond 24 Hours of Last Known Well: The SELECT Late Study

Current State of Evidence for Neuroimaging Paradigms in Management of Acute Ischemic Stroke

Stroke is the chief differential diagnosis in patient presenting to the emergency room with abrupt onset focal neurological deficits. Neuroimaging, including non-contrast computed tomography (CT), magnetic resonance imaging (MRI), vascular and perfusion imaging, is a cornerstone in the diagnosis and treatment decision-making. This review examines the current state of evidence behind the different imaging paradigms for acute ischemic stroke diagnosis and treatment, including current recommendations from the guidelines. Non-contrast CT brain, or in some centers MRI, can help differentiate ischemic stroke and intracerebral hemorrhage (ICH), a pivotal juncture in stroke diagnosis and treatment algorithm, especially for early window thrombolytics. Advanced imaging such as MRI or perfusion imaging can also assist making a diagnosis of ischemic stroke versus mimics such as migraine, Todd's paresis, or functional disorders. Identification of medium-large vessel occlusions with CT or MR angiography triggers consideration of endovascular thrombectomy (EVT), with additional perfusion imaging help identify salvageable brain tissue in patients who are likely to benefit from reperfusion therapies, particularly in the ≥6 h window. We also review recent advances in neuroimaging and ongoing trials in key therapeutic areas and their imaging selection criteria to inform the readers on potential future transitions into use of neuroimaging for stroke diagnosis and treatment decision making. ANN NEUROL 2024;95:1017-1034.

Blood glucose to predict symptomatic intracranial hemorrhage after endovascular treatment of acute ischemic stroke with large infarct core: a prospective observational study

Introduction

Symptomatic intracranial hemorrhage (sICH) is a serious complication of acute ischemic stroke (AIS) after endovascular treatment (EVT). Limited data exist regarding predictors and clinical implications of sICH after EVT, underscoring the significance of identifying risk factors to enhance prevention strategies. Therefore, the main objective of this study was to evaluate the incidence of sICH and identify its predictors after EVT in patients with large infarct core-AIS in the pre-circulation stage.

Methods

Using data from the EVT for the Pre-circulation Large Infarct Core-AIS Study, we enrolled patients who were treated with EVT from the Prospective Multicenter Cohort Study of Early Treatment in Acute Stroke (MAGIC) registry. Baseline demographics, medical history, vascular risk factors, blood pressure, stroke severity, radiographic features, and EVT details were collected. The patients were classified into three groups: without intracranial hemorrhage (ICH), with asymptomatic intracranial hemorrhage (aICH), and sICH, based upon the occurrence of sICH. The main outcomes were the occurrence of sICH according to the Heidelberg Bleeding Classification and functional condition at 90 days. Multivariate logistic regression analysis and receiver operating characteristic (ROC) curves were used to identify independent predictors of sICH after EVT.

Results

The study recruited a total of 490 patients, of whom 13.3% (n = 65) developed sICH. Patients with sICH had less favorable outcomes than those without intracranial hemorrhage (ICH) and those with aICH (13.8% vs. 43.5% vs. 32.2%, respectively; p < 0.001). The overall mortality was 41.8% (n = 205) at 90 days post-EVT. The univariate analysis revealed significant differences among the three groups in terms of blood glucose levels at admission, probability of favorable outcomes, incidence of brain herniation, and 90-day mortality. The multifactorial logistic regression analysis revealed that the blood glucose level at admission [odds ratio (OR) 1.169, p < 0.001, confidence interval (CI) 1.076-1.269] was an independent predictor of sICH. A blood glucose level of 6.95 mmol/L at admission was the best predictor of sICH, with an area under the ROC curve (AUC) of 0.685 (95% CI: 0.616-0.754).

Discussion

The study findings demonstrated that the probability of sICH after EVT was 13.3% in patients with pre-circulation large infarct core-AIS, and sICH increased the risk of an unfavorable prognosis. Higher blood glucose levels at admission were associated with sICH after EVT in patients with pre-circulation large infarct core AIS. These findings underscore the importance of early management strategies to mitigate this risk.

Is time really brain in stroke therapy?: A meta-analysis of mechanical thrombectomy up to 155 h post ictus

BACKGROUND AND OBJECTIVES

Mechanical thrombectomy (MT) has been established as the gold standard of treatment for patients with Acute Ischemic Stroke (AIS) who present up to 6 h after the onset of the stroke. Recently, the DEFUSE-3 and DAWN trials established the safety of starting the MT procedure up to 16 and 24 h after the patient was last seen well, respectively. The purpose of this study is to assess the safety and functional effects of thrombectomy in individuals with AIS detected at a late stage (> 24 h).

MATERIALS AND METHODS

PubMed, Web of Science, Embase, and Cochrane databases were thoroughly searched for research on MT in patients in the extremely late time window after AIS. The primary outcomes were symptomatic cerebral hemorrhage, 90-day mortality, Thrombolysis in Cerebral Infarction (TICI) 2b-3, and Modified Rankin Scale (mRS) 0-2.

RESULTS

Our study included fifteen studies involving a total of 1,221 patients who presented with AIS and an extended time window. The primary outcome of interest was the favorable functional outcome, mRS 0-2 at 90 days. The pooled proportion for this outcome was 45% (95% confidence interval 34-58%). Other outcomes included the TICI 2b or 3 (successful recanalization), which was reported in 12 studies and had a 79% incidence in the study population (95% CI 68-87%). Complications included: symptomatic intracranial hemorrhage (sICH), which revealed an incidence of 7% in the study population (95% CI 5-10%); and 90-day mortality, which reported a 27% incidence (95% CI 24-31%). In addition, we conducted a comparative analysis between endovascular treatment and standard medical therapy.

CONCLUSION

Our meta-analysis provides evidence that supports the need of further randomized and prospective clinical trials to better assess the effectiveness and safety of MT in these patients.

The prognostic value of ASPECTS in specific regions following mechanical thrombectomy in patients with acute ischemic stroke from large-vessel occlusion

Objective

The aim of this study is to investigate the relationship between the volume of specific regional infarction and the prognosis of patients who undergo mechanical thrombectomy (MT) for acute large vessel occlusion.

Methods

In this study, we collected the clinical and imaging features of patients with unilateral acute anterior circulation ischemic stroke from January 2021 to June 2023 in the Second Affiliated Hospital of Nanchang University. All patients underwent CT perfusion and non-contrast CT scan before MT. The ASPECTS was assessed based on imaging data, and artificial intelligence was used to obtain the percentage of infarction in each of the 10 regions of ASPECTS. According to the modified Rankin Scale, the patients were divided into the good prognosis group and poor prognosis group at the 90-day follow-up. Various indicators in the two groups were compared. Multivariable logistic regression was used to assess the risk factors for poor prognosis. The relationship between core infarction volume and the probability of poor prognosis was plotted to analyze the trend of poor prognosis with changes in the proportion of infarction volume. Finally, a receiver operating characteristic curve was constructed to analyze the predictive ability on poor prognosis.

Results

A total of 91 patients were included, with 58 patients having a good prognosis (mRS ≤ 2) and 33 patients having a poor prognosis (mRS ≥ 3). Multivariate analysis showed that NIHSS score and core infarction involving the internal capsule and M6 region were independent risk factors for poor prognosis. According to the linear correlation, a higher ratio of core infarction volume in the internal capsule or M6 region was linked to an increased risk of a poor prognosis. However, the non-linear analysis revealed that the prognostic impact of core infarction volume was significant when the ratio was greater than 69.7%. The ROC curve indicated that the combination of NIHSS score, infarct location, and the ratio of infarct volume has an AUC of 0.87, with a sensitivity of 84.8% and a specificity of 84.5%.

Conclusion

It is important to examine the location and volume of the infarct in the internal capsule and M6 when deciding whether to do a MT.

Stroke in the Time of Circadian Medicine

Time-of-day significantly influences the severity and incidence of stroke. Evidence has emerged not only for circadian governance over stroke risk factors, but also for important determinants of clinical outcome. In this review, we provide a comprehensive overview of the interplay between chronobiology and cerebrovascular disease. We discuss circadian regulation of pathophysiological mechanisms underlying stroke onset or tolerance as well as in vascular dementia. This includes cell death mechanisms, metabolism, mitochondrial function, and inflammation/immunity. Furthermore, we present clinical evidence supporting the link between disrupted circadian rhythms and increased susceptibility to stroke and dementia. We propose that circadian regulation of biochemical and physiological pathways in the brain increase susceptibility to damage after stroke in sleep and attenuate treatment effectiveness during the active phase. This review underscores the importance of considering circadian biology for understanding the pathology and treatment choice for stroke and vascular dementia and speculates that considering a patient's chronotype may be an important factor in developing precision treatment following stroke.

Intensive Blood Pressure Control After Endovascular Thrombectomy for Acute Ischemic Stroke: a Systematic Review and Meta-Analysis

BACKGROUND AND PURPOSE

Optimal clinical outcome with successful recanalization from endovascular thrombectomy (EVT) requires optimal blood pressure (BP) management. We aimed to evaluate the efficacy and safety of the intensive BP target (< 140 mm Hg) versus the standard BP target (< 180 mm Hg) after EVT for acute ischemic stroke.

METHODS

We conducted a systematic review and meta-analysis synthesizing evidence from randomized controlled trials (RCTs) obtained from PubMed, Embase Cochrane, Scopus, and WOS until September 7th, 2023. We used the fixed-effect model to report dichotomous outcomes using risk ratio (RR) and continuous outcomes using mean difference (MD), with a 95% confidence interval (CI).

PROSPERO ID

CRD42023463206.

RESULTS

We included four RCTs with 1559 patients. There was no difference between intensive BP and standard BP targets regarding the National Institutes of Health Stroke Scale (NIHSS) change after 24 h [MD: 0.44 with 95% CI (0.0, 0.87), P = 0.05]. However, the intensive BP target was significantly associated with a decreased risk of excellent neurological recovery (mRS ≤ 1) [RR: 0.87 with 95% CI (0.76, 0.99), P = 0.03], functional independence (mRS ≤ 2) [RR: 0.81 with 95% CI (0.73, 0.90), P = 0.0001] and independent ambulation (mRS ≤ 3) [RR: 0.85 with 95% CI (0.79, 0.92), P < 0.0001].

CONCLUSIONS

An intensive BP target after EVT is associated with worse neurological recovery and significantly decreased rates of functional independence and independent ambulation compared to the standard BP target. Therefore, the intensive BP target should be avoided after EVT for acute ischemic stroke.

Cost-effectiveness of endovascular treatment versus best medical management in basilar artery occlusion stroke: A U.S. healthcare perspective

INTRODUCTION

Two recent studies showed clinical benefit for endovascular treatment (EVT) in basilar artery occlusion (BAO) stroke up to 12 h (ATTENTION) and between 6 and 24 h from onset (BAOCHE). Our aim was to investigate the cost-effectiveness of EVT from a U.S. healthcare perspective.

MATERIALS AND METHODS

Clinical input data were available for both trials, which were analyzed separately. A decision model was built consisting of a short-run model to analyze costs and functional outcomes within 90 days after the index stroke and a long-run Markov state transition model (cycle length of 12 months) to estimate expected lifetime costs and outcomes from a healthcare and a societal perspective. Incremental cost-effectiveness ratios (ICER) were calculated, deterministic (DSA) and probabilistic (PSA) sensitivity analyses were performed.

RESULTS

EVT in addition to best medical management (BMM) resulted in additional lifetime costs of $32,063 in the ATTENTION trial and lifetime cost savings of $7690 in the BAOCHE trial (societal perspective). From a healthcare perspective, EVT led to incremental costs and effectiveness of $37,389 and 2.0 QALYs (ATTENTION) as well as $3516 and 1.9 QALYs (BAOCHE), compared to BMM alone. The ICER values were $-4052/QALY (BAOCHE) and $15,867/QALY (ATTENTION) from a societal perspective. In each trial, PSA showed EVT to be cost-effective in most calculations (99.9%) for a willingness-to-pay threshold of $100,000/QALY. Cost of EVT and age at stroke represented the greatest impact on the ICER.

DISCUSSION

From an economic standpoint with a lifetime horizon, EVT in addition to BMM is estimated to be highly effective and cost-effective in BAO stroke.

Endovascular treatment for acute ischemic stroke beyond the 24-h time window: Selection by target mismatch profile

INTRODUCTION

Endovascular treatment for acute ischemic stroke patients with large vessel occlusion (LVO) has been established as a promising clinical intervention within a late time window of 6-24 h after symptom onset. Patients with slow progression, however, may still benefit from endovascular treatment beyond the 24-h time window (very late window).

AIM

The aim of this study is to report insight into the potential clinical benefits of endovascular treatment for acute ischemic stroke beyond 24 h from symptom onset.

METHODS

A retrospective analysis was performed on consecutive patients undergoing endovascular treatment for acute anterior circulation LVO ischemic stroke beyond 24 h. Participants were recruited between July 2019 and November 2020. Patients were selected based on the DAWN/DEFUSE 3 criteria (Perfusion-RAPID, iSchemaView) and patients receiving treatment beyond 24 h were compared to a group of patients receiving endovascular treatment between 6 and 24 h after symptom onset. The primary outcome was the proportion of patients with functional independence at 90 days (modified Rankin Scale score of 0-2). The secondary outcomes were shift modified Rankin Scale (mRS) analysis and successful reperfusion was defined by thrombolysis in cerebral infarction (TICI) 2b-3 on the final procedure. Safety outcomes were symptomatic intracranial hemorrhage and death at the 90-day follow-up. Propensity score (PS)-matched analyses were employed to rectify the imbalanced baseline characteristics between the two groups.

RESULTS

A total of 166 patients were recruited with a median age of 63.0 (56.0-69.0) and 28.9% of all patients were females. Patients in the beyond 24-h group had a longer onset-to-groin time (median = 27.2 vs 14.3 h, p < 0.001) than those in the 6- to 24-h group. There were no statistically significant differences between the two groups in National Institutes of Health Stroke Scale (NIHSS) (median = 12.0 vs 15.0, p = 0.37), perfusion imaging characteristics (core: median = 11.0 vs 9.0 mL, p = 0.86; mismatch volume: median = 106.0 vs 96.0, p = 0.44; mismatch ratio = 6.46 vs 7.24, p = 0.91), and perfusion-to-groin time (median = 72.5 vs 76.0 min, p = 0.77). No significant differences were noted among patients between the two groups in the primary endpoint functional independence analysis (50.0% vs 46.6%, p = 0.77) and in the safety endpoint analysis: mortality (15.0% vs 11.0%, p = 0.71) or symptomatic hemorrhage (0% vs 3.42%, p > 0.999). In PS-matched analyses, there were no significant differences among patients between the two groups in functional independence (50.0% vs 54.8%, p = 0.74), mortality (16.7% vs 9.68%, p = 0.50), or symptomatic hemorrhage (0% vs 6.45%, p = 0.53).

CONCLUSION

Endovascular treatment can be performed safely and effectively in LVO patients beyond 24 h from symptom onset when selected by target mismatch profile. The clinical outcome of these patients was comparable to those treated in the 6- to 24-h window. Larger studies are needed to confirm these findings.

Association Between Hypoperfusion Intensity Ratio and Postthrombectomy Malignant Brain Edema for Acute Ischemic Stroke

BACKGROUND

Malignant brain edema (MBE) is a life-threatening complication that can occur after mechanical thrombectomy (MT) for acute ischemic stroke. The hypoperfusion intensity ratio (HIR) reflects the tissue-level perfusion status within the ischemic territory. This study investigated the association between HIR and MBE occurrence after MT in patients with anterior circulation large artery occlusion.

METHODS

We conducted a retrospective cohort study of patients who received MT at a comprehensive stroke center from February 2020 to June 2022. Using computed tomography perfusion, the HIR was derived from the ratio of tissue volume with a time to maximum (Tmax) > 10 s to that with a Tmax > 6 s. We dichotomized patients based on the occurrence of MBE following MT. The primary outcome, assessed using a multivariable logistic regression model, was the MBE occurrence post MT. The secondary outcome focused on favorable outcomes, defined as achieving a modified Rankin Scale score of 0-2 at 90 days.

RESULTS

Of the 603 included patients, 90 (14.9%) developed MBE after MT. The median HIR exhibited a significantly higher value in the MBE group compared with the non-MBE group (0.5 vs. 0.3; P < 0.001). Multivariable logistic regression analysis indicated that a higher HIR (adjusted odds ratio [aOR] 8.98; 95% confidence interval [CI] 2.85-28.25; P < 0.001), baseline large infarction (Alberta Stroke Program Early Computed Tomography Score < 6; aOR 1.77; 95% CI 1.04-3.01; P = 0.035), internal carotid artery occlusion (aOR 1.80; 95% CI 1.07-3.01; P = 0.028), and unsuccessful recanalization (aOR 8.45; 95% CI 4.75-15.03; P < 0.001) were independently associated with MBE post MT. Among those with successful recanalization, a higher HIR (P = 0.017) and baseline large infarction (P = 0.032) remained as predictors of MBE occurrence. Furthermore, a higher HIR (P = 0.001) and the occurrence of MBE (P < 0.001) both correlated with reduced odds of achieving favorable outcomes.

CONCLUSIONS

The presence of a higher HIR on pretreatment perfusion imaging serves as a robust predictor for MBE occurrence after MT, irrespective of successful recanalization.

Is thrombectomy indicated in all ischemic stroke with large vessel occlusion?

PURPOSE OF REVIEW

Purpose of this topical review is to examine the current randomized and nonrandomized evidence evaluating endovascular thrombectomy (EVT) in selected patient populations with acute ischemic stroke due to large vessel occlusions.

RECENT FINDINGS

After establishing EVT as the first-line treatment in patients with large vessel occlusions and limited ischemic changes on neuroimaging, recent trials successfully demonstrated efficacy and safety in patients with large core strokes and those with basilar occlusions up to 24 h of last known well. Nonrandomized evidence in patients with mild stroke severity, baseline disability, medium and distal vessel occlusions and time from last known well >24 h also suggested potential benefit of EVT in selected patients. Further randomized evidence will help establish EVT efficacy and safety in these populations.

SUMMARY

EVT is established as the de-facto treatment of choice in a significant proportion of patients presenting with acute ischemic stroke due to a large vessel occlusion and has shown potential benefits in additional patient subgroups. A rigorous risk-benefit assessment and discussions with patients and their families in the absence of randomized evidence should help facilitate an informed, individualized decision-making process for this revolutionary treatment in peripheral patient subgroups with limited evidence.

Is endovascular treatment still good for acute ischemic stroke in the elderly? A meta-analysis of observational studies in the last decade

Background

The lack of randomized evidence makes it difficult to establish reliable treatment recommendations for endovascular treatment (EVT) in elderly patients. This meta-analysis aims to evaluate the therapeutic effects of endovascular treatment for acute ischemic stroke in the elderly compared with younger patients.

Methods

Comprehensive literature retrieval was conducted to identify studies that directly compared the outcomes of EVT in elderly patients and those aged <80 years. The primary outcome was functional independence, defined as mRS 0-2 at 90 days after EVT. The secondary outcomes were the rate of successful recanalization, symptomatic intracranial hemorrhage (sICH) and mortality. Odds ratios (ORs) were estimated using a random effects model.

Results

In total, twenty-six studies with 9,492 enrolled participants were identified. Our results showed that, compared with patients aged <80 years undergoing EVT, EVT was associated with a lower rate of functional independence at 90 days (OR = 0.38; 95% CI, 0.33-0.45; p < 0.00001) and a higher mortality rate (OR = 2.51; 95% CI, 1.98-3.18; p < 0.00001) in the elderly. Furthermore, even without a significantly observed increase in sICH (OR = 1.19; 95% CI, 0.96-1.47; p = 0.11), EVT appeared to be associated with a lower rate of successful recanalization (OR = 0.81; 95% CI, 0.68-0.96; p = 0.02).

Conclusion

Evidence from observational studies revealed that EVT has less functional outcomes in elderly patients with acute ischemic stroke. Further studies are needed to better identify patients aged ≥80 years who could potentially benefit from EVT.

Atrial Fibrillation and Clinical Outcomes of Endovascular Thrombectomy for Acute Ischemic Stroke: A Meta-Analysis of Adjusted Effect Estimates

BACKGROUND

The impact of atrial fibrillation (AF) on the clinical outcomes in patients with acute ischemic stroke (AIS) who received endovascular thrombectomy remains unclear. We aimed to perform a meta-analysis of adjusted effect estimates to examine the association between the presence of AF and the clinical outcomes in patients with AIS who received endovascular thrombectomy.

METHODS AND RESULTS

We searched PubMed, Embase, and the Cochrane database between January 1, 2013 and July 10, 2023. Data were meta-analyzed to compare the outcomes among patients with AIS with and without AF who received endovascular thrombectomy. Our primary outcome was 90-day functional independence defined as a modified Rankin Scale score of 0 to 2. Secondary outcomes included excellent independence (90-day modified Rankin Scale score of 0-1), 90-day mortality, symptomatic intracranial hemorrhage, and any intracranial hemorrhage. Eighteen observational studies comprising 16 096 patients with AIS (mean age, 70.1 years; women, 48.2%; 6862 with AF versus 9234 without AF) were included. There were no statistically significant differences for modified Rankin Scale score of 0 to 2 (pooled odds ratio [OR], 1.14 [95% CI, 0.95-1.37]; [95% prediction interval [PI], 0.72-1.80]), mortality (OR, 0.92 [95% CI, 0.79-1.08]; [95% PI, 0.77-1.11]), symptomatic intracranial hemorrhage (OR, 0.97 [95% CI, 0.71-1.32]; [95% PI, 0.43-2.17]), and any intracranial hemorrhage (OR, 1.08 [95% CI, 0.91-1.28]; [95% PI, 0.74-1.58]) among patients with AIS with and without AF.

CONCLUSIONS

This meta-analysis detected no significant differences in 90-day functional outcomes, mortality, and intracerebral hemorrhage risk after endovascular thrombectomy in patients with AIS with and without AF.

REGISTRATION

URL: https://www.crd.york.ac.uk/prospero; Unique identifier: CRD 42021293511.

Endovascular therapy beyond 24 hours for anterior circulation large vessel occlusion or stenosis in acute ischemic stroke: a retrospective study

Background

To assess the clinical and safety outcomes of endovascular treatment (EVT) administered more than 24 h after the onset of symptoms in patients with acute ischemic stroke resulting from anterior circulation large-vessel occlusion or stenosis (AIS-ACLVO/S).

Methods

We enrolled consecutive AIS-ACLVO/S patients who received EVT in our hospital between January 2019 and February 2022 and divided them into two groups based on the time from AIS onset to EVT: EVT < 24 h group and EVT >24 h group. The successful reperfusion (modified thrombolysis in cerebral infarction, [mTICI] ≥2b), 90-day modified Rankin Scale score (mRS), intracranial hemorrhage (ICH), and symptomatic ICH (sICH), as well as mortality, were analyzed in the two groups of patients.

Results

A total of 239 patients were included in the study, with 214 patients in the EVT < 24 h group (67.8 ± 0.8 years, 126 males) and 25 patients in the EVT > 24 h group (62.80 ± 2.0 years, 22 males). Both groups were similar in terms of hypertension, diabetes history, responsible vessels, and Alberta stroke program early computed tomography scores (p > 0.05). However, the EVT < 24 h group had significantly higher age, history of atrial fibrillation, proportion of patients receiving intravenous thrombolysis, and NIHSS scores before EVT than the EVT > 24 h group. AIS etiology differed between the groups, with more cases of large artery atherosclerosis in the EVT > 24-h group and more cases of cardioembolism in the EVT < 24-h group. Successful reperfusion (mTICI ≥2b), ICH, and sICH were similar between the groups. The 90-day functional independence rate (mRS ≤ 2) was significantly higher in the EVT > 24-h than in the EVT < 24-h group (80% vs. 39.7%, p < 0.001), while the 90-day mortality rate was lower in the EVT > 24-h group (0% vs. 24.8%, p < 0.001).

Conclusion

In our study, we found that EVT beyond 24 h of symptom onset in patients selected with multimodal MR screening, was associated with high functional independence rates and low mortality. Larger or randomized studies are needed to confirm these findings.

Brain-derived Tau for Monitoring Brain Injury in Acute Ischemic Stroke

The evolution of infarcts varies widely among patients with acute ischemic stroke (IS) and influences treatment decisions. Neuroimaging is not applicable for frequent monitoring and there is no blood-based biomarker to track ongoing brain injury in acute IS. Here, we examined the utility of plasma brain-derived tau (BD-tau) as a biomarker for brain injury in acute IS. We conducted the prospective, observational Precision Medicine in Stroke [PROMISE] study with serial blood sampling upon hospital admission and at days 2, 3, and 7 in patients with acute ischemic stroke (IS) and for comparison, in patients with stroke mimics (SM). We determined the temporal course of plasma BD-tau, its relation to infarct size and admission imaging-based metrics of brain injury, and its value to predict functional outcome. Upon admission (median time-from-onset, 4.4h), BD-tau levels in IS patients correlated with ASPECTS (ρ=-0.21, P<.0001) and were predictive of final infarct volume (ρ=0.26, P<.0001). In contrast to SM patients, BD-tau levels in IS patients increased from admission (median, 2.9 pg/ml [IQR, 1.8-4.8]) to day 2 (median time-from-onset, 22.7h; median BD-tau, 5.0 pg/ml [IQR, 2.6-10.3]; P<.0001). The rate of change of BD-tau from admission to day 2 was significantly associated with collateral supply (R2=0.10, P<.0001) and infarct progression (ρ=0.58, P<.0001). At day 2, BD-tau was predictive of final infarct volume (ρ=0.59, P<.0001) and showed superior value for predicting the 90-day mRS score compared with final infarct volume. In conclusion, in 502 patients with acute IS, plasma BD-tau was associated with imaging-based metrics of brain injury upon admission, increased within the first 24 hours in correlation with infarct progression, and at 24 hours was superior to final infarct volume in predicting 90-day functional outcome. Further research is needed to determine whether BD-tau assessments can inform decision-making in stroke care.

Comprehensive analysis of the impact of procedure time and the 'golden hour' in subpopulations of stroke thrombectomy patients

OBJECTIVE

To evaluate the effect of procedure time on thrombectomy outcomes in different subpopulations of patients undergoing endovascular thrombectomy (EVT), given the recently expanded indications for EVT.

METHODS

This multicenter study included patients undergoing EVT for acute ischemic stroke at 35 centers globally. Procedure time was defined as time from groin puncture to successful recanalization (Thrombolysis in Cerebral Infarction score ≥2b) or abortion of procedure. Patients were stratified based on stroke location, use of IV tissue plasminogen activator (tPA), Alberta Stroke Program Early CT score, age group, and onset-to-groin time. Primary outcome was the 90-day modified Rankin Scale (mRS) score, with scores 0-2 designating good outcome. Secondary outcome was postprocedural symptomatic intracranial hemorrhage (sICH). Multivariate analyses were performed using generalized linear models to study the impact of procedure time on outcomes in each subpopulation.

RESULTS

Among 8961 patients included in the study, a longer procedure time was associated with higher odds of poor outcome (mRS score 3-6), with 10% increase in odds for each 10 min increment. When procedure time exceeded the 'golden hour', poor outcome was twice as likely. The golden hour effect was consistent in patients with anterior and posterior circulation strokes, proximal or distal occlusions, in patients with large core infarcts, with or without IV tPA treatment, and across age groups. Procedures exceeding 1 hour were associated with a 40% higher sICH rate. Posterior circulation strokes, delayed presentation, and old age were the variables most sensitive to procedure time.

CONCLUSIONS

In this work we demonstrate the universality of the golden hour effect, in which procedures lasting more than 1 hour are associated with worse clinical outcomes and higher rates of sICH across different subpopulations of patients undergoing EVT.

Ultra-early rt-PA administration should improve patient outcome on mechanical thrombectomy: Post hoc analysis of SKIP

BACKGROUND

To investigate whether ultra-early recombinant tissue-plasminogen activator (rt-PA) administration can improve patient outcomes on mechanical thrombectomy (MT) in patients with large vessel occlusion (LVO).

METHODS

Participants comprised rt-PA-eligible 204 patients with internal carotid artery or middle cerebral artery occlusion in the SKIP trial, who were randomly assigned to receive mechanical thrombectomy alone or combined intravenous thrombolysis (rt-PA: alteplase at 0.6 mg/kg) plus mechanical thrombectomy. We assessed associations between onset-to-puncture time and onset-to-rt-PA administration time and frequency of favorable outcome at 90 days and any intracerebral hemorrhage (ICH) at 36 h after onset.

RESULTS

As a cut-off onset-to-puncture time for favorable outcome, receiver operating characteristic curves defined 2.5 h (57% sensitivity, 62% specificity). For onset-to-puncture times ≤2.5 h and > 2.5 h, frequencies of favorable outcomes were 72% and 63% (p = 0.402) in patients with rt-PA therapy and 44% and 58% (p = 0.212) in patients without rt-PA therapy, respectively. In terms of onset-to-rt-PA administration time, frequencies of favorable outcomes among patients with ultra-early rt-PA administration at ≤100, >100 min after onset, and without rt-PA therapy with onset-to-puncture time ≤ 2.5 h, and with and without rt-PA therapy with onset-to-puncture time > 2.5 h were 84% and 64%, 63%, and 44% and 58%, respectively (p = 0.025). Frequencies of any ICH among those patients were 37% and 32%, 32%, and 63% and 40%, respectively (p = 0.006).

CONCLUSION

Ultra-early rt-PA administration should improve patient outcomes on mechanical thrombectomy among patients with LVO. Relatively late rt-PA administration might increase the frequency of any ICH.

Association of the time of day of EVT with clinical outcomes and benefit from successful recanalization after stroke

Experimental and neuroimaging studies suggest an influence of the time of day on acute infarct growth, but whether this could inform patient selection for acute treatments is uncertain. In a multicenter cohort of 9357 stroke patients undergoing endovascular treatment, morning treatment (05:00-10:59) was associated with lowest 90-day mRS scores (adjusted odds ratio, 1.27 [95% CI, 1.08-1.47]; p = 0.004). The association between successful recanalization and outcome was stronger in morning compared to evening-treated patients (pia  = 0.046) with treatment benefit persisting until 24 h for morning-treated compared to 11.5 h for evening-treated patients suggesting that the time of day might inform patient selection for EVT.

Mechanical thrombectomy beyond 24 hours from last known well in tandem lesions: A multicenter cohort study

BACKGROUND

While recent studies suggest a benefit of mechanical thrombectomy (MT) for the treatment of patients with isolated large vessel occlusions presenting after 24 hours from the last known well (LKW), the effect of MT for acute cervical tandem lesions (TLs) beyond 24 hours remains unknown. We aimed to evaluate the safety and effectiveness of MT beyond 24 hours of LKW in patients with TLs.

METHODS

We conducted a subanalysis study of patients with anterior circulation TL enrolled in a large, multicenter registry between January 2015 and December 2020. Patients were divided into 2 groups: MT beyond 24 hours versus MT 0-24-hour window. Outcomes of interest were functional independence (90-day modified Rankin scale 0-2), complete reperfusion (modified thrombolysis in cerebral infarction 3), delta NIH Stroke Scale (NIHSS), symptomatic intracranial hemorrhage (sICH), parenchymal hematoma 2 (PH2), in-hospital mortality, and 90-day mortality. Inverse probability of treatment weighting (IPTW) was used to balance the groups.

RESULTS

Overall, 589 participants were included, with 33 treated beyond 24 hours and 556 treated in the 0-24-hour window. After IPTW, we found no significant difference in the rates of achieving functional independence (odds ratio (OR) = 0.51; 95% confidence interval (CI) 0.22-1.16; p = 0.108), complete reperfusion (OR = 1.35; 95% CI 0.60-3.05; p = 0.464), sICH (OR = 1.96; 95% CI 0.37-10.5; p = 0.429), delta NIHSS (β = -3.61; 95% CI -8.11 to 0.87; p = 0.114), PH2 (OR = 1.46; 95% CI 0.29-7.27; p = 0.642), in-hospital mortality (OR = 1.74; 95% CI 0.52-5.86; p = 0.370), or 90-day mortality (OR = 1.37; 95% CI 0.49-3.83; p = 0.544) across both time windows.

CONCLUSIONS

Our results suggest that MT appears to benefit patients with TLs beyond 24 hours from LKW. Future prospective studies are warranted.

Treatment with intravenous alteplase in ischaemic stroke patients with onset time between 4.5 and 24 hours (HOPE): protocol for a randomised, controlled, multicentre study

BACKGROUND

While intravenous thrombolysis is recommended for patients who had an acute ischaemic stroke (AIS) within 4.5 hours of symptom onset, there are few randomised trials investigating the benefits of thrombolysis beyond this therapeutic window.

AIM

To determine whether patients who had an AIS selected with the presence of potentially salvageable tissue on CT perfusion at 4.5-24 hours after stroke onset (for stroke with unknown onset time, the midpoint of the time last known to be well and symptom recognition time; for wake-up stroke, the midpoint of the time last known to be well or sleep onset and wake up time) will benefit from intravenous thrombolysis.

DESIGN

HOPE is a prospective, multicentre, randomised, open-label blinded endpoint trial with the stage of phase III. The treatment allocation employs 1:1 randomisation. The treatment arm under investigation is alteplase with standard therapy, the control arm is standard therapy. Eligibility imaging criteria include ischaemic core volume ≤70 mL, penumbra ≥10 mL and mismatch ≥20%.

STUDY OUTCOMES

The primary outcome is non-disabled functional outcome (assessed as modified Rankin Scale score of 0-1 at 90 days).

DISCUSSION

HOPE is the first trial to investigate whether intravenous thrombolysis with alteplase offers benefits in patients who had an AIS presenting within 4.5-24 hours, which has the potential to extend time window and expand eligible population for thrombolysis therapy.

Safety and efficacy of endovascular recanalization in patients with mild anterior stroke due to large-vessel occlusion exceeding 24 hours

BACKGROUND

Endovascular recanalization (ER) has demonstrated efficacy as a treatment modality for patients presenting with acute ischemic stroke (AIS) caused by large-vessel occlusion (LVO) within a 24-hour timeframe. Nevertheless, the safety and effectiveness of ER in patients with a time of onset exceeding 24 h remain uncertain.

OBJECTIVE

To evaluate the safety and efficacy of ER treatment for mild ischemic stroke beyond 24-h from symptom onset.

METHODS

A retrospectively maintained database of mild AIS due to LVO from March2018 to September 2022 at a comprehensive stroke center was screened.Patients received ER or standard medical therapies (SMT) for anterior circulation AIS due to LVO > 24-h were selected.

RESULTS

We included 47 LVO patients with mild AIS beyond 24-h who suffered neurological deterioration (ND). 34 of these patients underwent ER, the other 13 received SMT. The technical success rate of recanalization was 82.4% (28/34). Patients received ER had significantly lower NIHSS score at discharge and 90-day mRS score (p = 0.028, p = 0.037, respectively) compared to SMT. In addition, they had significantly lower 90-day recurrence of ischemic stroke and lower incidence of moderate-severe stroke (with a NIHSS score at least 5) (p = 0.037, p = 0.033). There were 4 patients (11.7%) had perioperative complications, and no symptomatic intracranial hemorrhage occurred.

CONCLUSION

ER treatment for mild AIS due to LVO encountered ND was generally safe and effective, even beyond 24-h, and resulted in a good prognosis and lower 90-day recurrence compared to SMT.

Endovascular thrombectomy beyond 24 hours from last known well: a systematic review with meta-analysis

BACKGROUND

Different studies have demonstrated the benefit of endovascular treatment (EVT) up to 24 hours after acute ischemic stroke (AIS) onset. Recent cohort observational studies suggest that patients with large vessel occlusion AIS may benefit from EVT beyond 24 hours from the last known well (LKW) when adequately selected. We aimed to examine the safety and efficacy of EVT beyond 24 hours from LKW using a meta-analysis of all the literature available.

METHODS

A systematic search from inception to April 2023 was conducted for studies including AIS patients with EVT beyond 24 hours from LKW in Medline, Embase, Scopus, and Web of Science. Outcomes of interest included favorable functional outcome (90-day modified Rankin scale (mRS) 0-2), successful reperfusion (modified Thrombolysis in Cerebral Infarction (mTICI) 2b-3), symptomatic intracerebral hemorrhage (sICH), and 90-day mortality. Data were pooled using a random-effects model.

RESULTS

Twelve studies with 894 patients were included. The rate of favorable functional outcome was 40% (95% CI 31% to 49%; I²=76%). The rate of successful reperfusion was 83% (95% CI 80% to 85%; I²=0%). The sICH rate was 7% (95% CI 5% to 9%; I²=0%) and the 90-day mortality rate was 28% (95% CI 24% to 33%; I²=0%). There was no significant difference in favorable outcomes (OR=0.69; 95% CI 0.41 to 1.14) and 90-day mortality (OR=1.35; 95% CI 0.90 to 2.00) among patients who underwent EVT <24 hours versus >24 hours.

CONCLUSIONS

EVT beyond 24 hours from LKW may achieve favorable clinical outcomes and high reperfusion rates, with acceptable intracranial hemorrhage rates in selected patients. Considering the current certainty of the evidence and heterogenous individual study results, larger prospective trials are warranted.

Endovascular Thrombectomy for Anterior Circulation Large Vessel Occlusion Stroke: An Evolution of Trials

The last decade's progress in demonstrating the clinical benefit of endovascular thrombectomy (EVT) in patients with large vessel occlusion stroke has transformed the paradigm of care for these patients. This review presents the milestones in implementing EVT as standard of care, demonstrates the current state of evidence, provides guidance for identifying the candidate patient for EVT, and highlights unsolved and controversial issues. Ongoing trials investigate broadening of EVT indications for patients who present with large core infarction, adjunctive intra-arterial thrombolysis, medium vessel occlusion, low NIHSS, and tandem occlusion.

Quantification of Penumbral Volume in Association With Time From Stroke Onset in Acute Ischemic Stroke With Large Vessel Occlusion

Importance

The benefit of reperfusion therapies for acute ischemic stroke decreases over time. This decreasing benefit is presumably due to the disappearance of salvageable ischemic brain tissue (ie, the penumbra).

Objective

To study the association between stroke onset-to-imaging time and penumbral volume in patients with acute ischemic stroke with a large vessel occlusion.

Design, Setting, and Participants

A retrospective, multicenter, cross-sectional study was conducted from January 1, 2015, to June 30, 2022. To limit selection bias, patients were selected from (1) the prospective registries of 2 comprehensive centers with systematic use of magnetic resonance imaging (MRI) with perfusion, including both thrombectomy-treated and untreated patients, and (2) 1 prospective thrombectomy study in which MRI with perfusion was acquired per protocol but treatment decisions were made with clinicians blinded to the results. Consecutive patients with acute stroke with intracranial internal carotid artery or first segment of middle cerebral artery occlusion and adequate quality MRI, including perfusion, performed within 24 hours from known symptoms onset were included in the analysis.

Exposures

Time from stroke symptom onset to baseline MRI.

Main Outcomes and Measures

Penumbral volume, measured using automated software, was defined as the volume of tissue with critical hypoperfusion (time to maximum >6 seconds) minus the volume of the ischemic core. Substantial penumbra was defined as greater than or equal to 15 mL and a mismatch ratio (time to maximum >6-second volume/core volume) greater than or equal to 1.8.

Results

Of 940 patients screened, 516 were excluded (no MRI, n = 19; no perfusion imaging, n = 59; technically inadequate perfusion imaging, n = 75; second segment of the middle cerebral artery occlusion, n = 156; unwitnessed stroke onset, n = 207). Of 424 included patients, 226 (53.3%) were men, and mean (SD) age was 68.9 (15.1) years. Median onset-to-imaging time was 3.8 (IQR, 2.4-5.5) hours. Only 16 patients were admitted beyond 10 hours from symptom onset. Median core volume was 24 (IQR, 8-76) mL and median penumbral volume was 58 (IQR, 29-91) mL. An increment in onset-to-imaging time by 1 hour resulted in a decrease of 3.1 mL of penumbral volume (β coefficient = -3.1; 95% CI, -4.6 to -1.5; P < .001) and an increase of 3.0 mL of core volume (β coefficient = 3.0; 95% CI, 1.3-4.7; P < .001) after adjustment for confounders. The presence of a substantial penumbra ranged from approximately 80% in patients imaged at 1 hour to 70% at 5 hours, 60% at 10 hours, and 40% at 15 hours.

Conclusions and Relevance

Time is associated with increasing core and decreasing penumbral volumes. Despite this, a substantial percentage of patients have notable penumbra in extended time windows; the findings of this study suggest that a large proportion of patients with large vessel occlusion may benefit from therapeutic interventions.

Endovascular Therapy for Stroke Presenting Beyond 24 Hours: A Systematic Review and Meta-analysis

Importance

Previous randomized clinical trials (RCTs) have supported the use of endovascular therapy (EVT) in late-window acute ischemic stroke (AIS; 6-24 hours). However, little is known about the use of EVT in very late-window AIS (>24 hours).

Objective

To examine outcomes following EVT for very late-window AIS.

Data Sources

A systematic review of the English language literature was conducted using Web of Science, Embase, Scopus, and PubMed to search for articles published from database inception until December 13, 2022.

Study Selection

This systematic review and meta-analysis included published studies regarding very late-window AIS treated with EVT. Multiple reviewers screened studies, and an extensive manual search of the references of included articles was performed to identify any missed articles. Of the 1754 initially retrieved studies, 7 published between 2018 and 2023 were ultimately included.

Data Extraction and Synthesis

Data were extracted independently by multiple authors and evaluated for consensus. Data were pooled using a random-effects model. This study is reported per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guideline, and the protocol was prospectively registered with PROSPERO.

Main Outcomes and Measures

The primary outcome of interest was functional independence, as assessed with 90-day modified Rankin Scale (mRS) scores (0-2). Secondary outcomes included thrombolysis in cerebral infarction (TICI) scores (2b-3 or 3), symptomatic intracranial hemorrhage (sICH), 90-day mortality, early neurological improvement (ENI), and early neurological deterioration (END). Frequencies and means were pooled with the corresponding 95% CIs.

Results

This review included 7 studies involving a total of 569 patients. The mean baseline National Institutes of Health Stroke Scale score was 13.6 (95% CI, 11.9-15.5), and the mean Alberta Stroke Program Early CT Score was 7.9 (95% CI, 7.2-8.7). The mean time from last known well and/or onset to puncture was 46.2 hours (95% CI, 32.4-65.9 hours). Frequencies for the primary and secondary outcomes were 32.0% (95% CI, 24.7%-40.2%) for functional independence (90-day mRS scores of 0-2) and 81.9% (95% CI, 78.5%-84.9%) for TICI scores of 2b to 3, 45.3% (95% CI, 36.6%-54.4%) for TICI scores of 3, 6.8% (95% CI, 4.3%-10.7%) for sICH, and 27.2% (95% CI, 22.9%-31.9%) for 90-day mortality. In addition, frequencies were 36.9% (95% CI, 26.4%-48.9%) for ENI and 14.3% (95% CI, 7.1%-26.7%) for END.

Conclusions and Relevance

In this review, EVT for very late-window AIS was associated with favorable frequencies of 90-day mRS scores of 0 to 2 and TICI scores of 2b to 3 and with low frequencies of 90-day mortality and sICH. These results suggest that EVT may be safe and associated with improved outcomes for very late-window AIS, although RCTs and prospective, comparative studies are needed to determine which patients may benefit from very late intervention.