Stent-retriever thrombectomy after intravenous t-PA vs. t-PA alone in stroke

Geographic Access to High-Volume Mechanical Thrombectomy Centers in Florida, 2019

Background and Objectives

Mechanical thrombectomy (MT) improves outcomes for acute ischemic stroke (AIS) due to large vessel occlusion, but is time sensitive and requires specialized infrastructure. Professional organizations and certification bodies have promulgated minimum procedural volume standards for centers and for individual proceduralists but it is unclear whether enforcing these requirements would decrease geographic access to MT. Therefore, we sought to evaluate the potential impact of applying a minimum procedural volume threshold on geographic access to MT.

Methods

We identified all hospital discharges for stroke where an MT procedure was performed at any nonfederal hospital in Florida in 2019 using statewide hospital discharge data. We then generated geographic service area maps based on prespecified ground transport distances for the subset of hospitals that performed at least 1 MT and for those that performed at least 15 MTs that year, the minimum volume threshold required for thrombectomy capable and comprehensive stroke centers by the Joint Commission. Then, using zip code centroids and patient-level discharge hospital data, we computed the proportion of patients with AIS who lived within each of the generated service areas.

Results

A total of 105 of 297 hospitals performed MT; of those, 51 (17%) were low-volume centers (1-14 MTs/year) and 54 (18%) were high-volume centers (≥15 MTs/year). High-volume centers accounted for nearly 95% of all MTs performed in the state. Most patients hospitalized with AIS (87%) lived within 20 miles (or an estimated as a 1-hour driving time) of a hospital that performed at least 1 MT, and all (100%) lived within 115 miles (or estimated as 3-hour driving time). Setting a minimum MT volume threshold of 15 would decrease the proportion of stroke patients living within 1-hour driving time of an MT center from 87% to 77%.

Discussion

In 2019, most Florida stroke patients lived within a 1-hour ground transport time to a center that performed at least 1 MT and all lived within 3-hour driving time of an MT center, irrespective of whether a minimum procedural volume threshold of 15 cases per year was applied or not.

Prognostic Value of Venous Outflow Profiles on Multiphase CT Angiography for the Patients with Acute Ischemic Stroke After Endovascular Thrombectomy

To evaluate the prognostic value of venous outflow (VO) profiles evaluated on multiphase CTA (mCTA) for the patients with acute ischemic stroke (AIS) after endovascular thrombectomy (EVT). We retrospectively collected 150 patients with AIS who underwent pre-treatment CT perfusion (CTP) evaluation and subsequent EVT from April 2018 to April 2022. Three-phases (peak arterial phase, peak venous phase, late venous phase) CTA was reconstructed from CTP raw data, and VO was evaluated on three-phases CTA, respectively. Favorable VO was regarded as a cortical vein opacification score of 3-6, and unfavorable VO as a score of 0-2. Good outcome was defined as modified Rankin Scale score of 0-2 at 90 days after EVT. Multivariate logistic regression analysis was performed to explore the predictors of good outcome. Prognostic value was assessed and compared using receiver operating characteristic (ROC) curves and Delong test. We found that good outcome was achieved in 85 (56.7%) patients. Among the mCTA-derived VO profiles, only favorable peak venous phase VO was found to be independently associated with good outcome (P < 0.001). After integrating favorable peak venous phase VO with lower post-treatment National Institute of Health Stroke Scale score at 24 hours, successful recanalization and favorable hypoperfusion intensity ratio, the predictive ability for a good outcome was significantly improved than before (area under the ROC curve; 0.947 vs 0.881; P = 0.002). This study supports that favorable peak venous VO profiles on mCTA might be a promising biomarker in predicting the good outcome in patients with AIS after EVT.

Higher baseline subcortical net water uptake in computed tomography predicts malignant middle cerebral artery infarction in patients with acute ischemic stroke

AIM

The objective of this study was to assess the predictive performance of net water uptake (NWU) based on the Alberta stroke program early CT score (ASPECTS) from different ASPECT regions in relation to the development of malignant middle cerebral artery (MCA) infarction.

MATERIAL AND METHODS

Patients with acute ischemic stroke (AIS) of the MCA territory were retrospectively enrolled between January 2019 and July 2022. Patients were divided into two groups according to the follow-up CT after 24-48 hours: malignant and nonmalignant infarction. NWUs were measured on diverse ASPECT regions on admission non-contrast CT, namely affected ASPECTS-NWU (af-ASPECTS-NWU), subcortical ASPECTS-NWU (sc-ASPECTS-NWU), and cortical ASPECTS-NWU (c-ASPECTS-NWU). Baseline characteristics were collected for univariate analyses and multivariate regression analyses to explore the independent risk factors for malignant infarction. Receiver operating characteristic (ROC) curves were plotted and compared.

RESULTS

patients were included in the final analysis. Malignant MCA infarction was achieved in 42 (27.45%) patients and nonmalignant was 111 (72.55%). Compared with the nonmalignant infarction group, higher baseline National Institute of Health stroke scale (NIHSS) score, af-ASPECTS-NWU, c-ASPECTS-NWU, sc-ASPECTS-NWU, and lower ASPECTS were noted in the malignant infarction group (all P < 0.001). Multivariate logistic regression showed that only baseline sc-ASPECTS-NWU (>3.6%) was a positive factor for malignant MCA infarction. The ROC analysis indicated the highest predictive value of sc-ASPECTS-NWU for indicating malignant infarction with the area under ROC curve (AUC) 0.91.

CONCLUSION

Higher baseline sc-ASPECTS-NWU was a quantitative predictor for malignant MCA infarction in patients with AIS, which could be helpful for treatment decisions.

A systematic review of the socioeconomic impact of mechanical thrombectomy for acute ischemic stroke

BACKGROUND

Mechanical Thrombectomy (MT) is an efficacious treatment for severe acute ischemic stroke patients. However, access to MT is limited in many parts of the world, partly due to economic barriers. The purpose of this systematic review is to provide an updated frame about the socioeconomic impact of MT.

METHODS

To carry out this systematic review we used the PRISMA guidelines. We included scientific articles analyzing the socioeconomic impact of MT for acute ischemic stroke, in which MT was compared to best medical therapy (BMT). The online databases of Pubmed, Scopus and Web of Science were used as main sources of information. To carry out the comparative analysis, the incremental cost-effectiveness ratio (ICER) was used, relating the cost to quality-adjusted life-year (QALY). Risk of bias was assessed with the Consensus Health Economic Criteria (CHEC) and the Consolidated Health Economic Evaluation Reporting Standards (CHEERS).

RESULTS

Eight hundred thirty-two studies were identified in this systematic review. As a result, studies that used cost-effectiveness analysis show that MT saves costs in the long term and cost-utility analysis show that the cost per QALY is reasonable with a mean ICER value of $14242.36/QALY.

CONCLUSIONS

MT has a favorable socioeconomic impact, as derived from cost-effectiveness and cost-utility analyses. Therefore, public policies should encourage the implementation of MT for stroke patients around the world.

Adaptive Clinical Trials in Stroke

Designing a clinical trial to evaluate the efficacy of an intervention is often complicated by uncertainty over aspects of the study population, potential treatment effects, most relevant outcomes, dropouts, and other factors. However, once participants begin to be enrolled and partial trial data become available, this level of uncertainty is reduced. Adaptive clinical trials are designed to take advantage of the accumulating data during the conduct of a trial to make changes according to prespecified decision rules to increase the likelihood of success or statistical efficiency. Common adaptive rules address early stopping for benefit or futility, sample size reestimation, adding or dropping treatment arms or altering randomization ratios, and changing the eligibility criteria to focus on responder patient subgroups. Adaptive clinical trials are gaining popularity for clinical stroke research. We provide an overview of the methods, practical considerations, challenges and limitations, and potential future role of adaptive clinical trials in advancing knowledge and practice in stroke.

Ischemic core volumes and collateral status have diurnal fluctuations - A retrospective cohort study of 18,137 patients

INTRODUCTION

Recent observations suggest that circadian rhythms are implicated in the timing of stroke onset and the speed of infarct progression. We aimed to replicate these observations in a large, multi-center, automated imaging database.

METHODS

The RAPID Insights database was queried from 02/01/2016 to 01/31/2022 for patients with perfusion imaging and automated detection of an ischemic stroke due to a presumed large vessel occlusion. Exclusion criteria included: patient age ≤25, mismatch volume of <0 cc, and failure to register a positive value on either relative cerebral blood flow (rCBF) reduction of 38% less than normal or total mismatch volume. Imaging time was subdivided into three epochs: Night: 23:00h-06:59h and Day: 07:00h-14:59h, and Evening: 15:00h-22:59h. Perfusion parameters were defined using standard conventions for core volume, penumbra, and collateral circulation (measured via the Hypoperfusion Intensity Ratio, HIR). Statistical significance was tested using a sinusoidal regression analysis.

RESULTS

A total of 18,137 cases were analyzed. The peak incidence of stroke imaging of patients with LVOs occurred around noon. A sinusoidal pattern was present, with larger ischemic core volumes and higher HIR during the night compared to the day: peak ischemic core volume of 23.4 cc occurred with imaging performed at 3:56 AM (p<0.001) and peak HIR of 0.35 at 3:40 AM (p<0.001).

CONCLUSION

We found that ischemic core volumes were larger and collateral status worse at nighttime compared to daytime in this large national database. These findings support prior data suggesting that poor collateral recruitment with subsequent larger ischemic stroke volumes may occur at night.

Intracranial artery calcification: Frequency, determinants, and modification of outcomes from endovascular thrombectomy

INTRODUCTION

Intracranial artery calcification (ICAC) is a common finding on computed tomography (CT) in patients presenting with large vessel occlusion acute ischemic stroke (LVO-AIS) and could serve as a useful biomarker of intracranial atherosclerosis and altered intracranial vessel pliability in patients undergoing endovascular thrombectomy (EVT).

METHODS

This was a retrospective cohort study analyzing consecutive patients undergoing CT head prior to EVT between 2016 and 2020. Extent of ICAC proximal to the target vessel was scored using a validated grading scale examining thickness and circumferential extent of calcifications. The relationship between 3 levels of ICAC burden and procedural, clinical, and safety outcomes was analyzed.

RESULTS

Among 86 patients meeting inclusion criteria, ICAC of any degree was present in 72.1 %. Median ICAC score was 3 [IQR 0-4]. There was a U-shaped association between ICAC score and successful reperfusion: 90.9 %, 65.7 %, and 94.4 % in the low, intermediate, and high ICAC score groups, respectively (p = 0.008). Use of rescue intervention, most often angioplasty and stenting, was greatest in the high ICAC score group: 3.0 % vs. 5.7 % vs. 22.2 % (p = 0.05). Functional independence at 90 days did not differ significantly among groups (41.7 % vs. 31.0 % vs. 15.4 %, p = 0.26), nor did rates of symptomatic intracranial hemorrhage (15.2 % vs. 14.3 % vs. 16.7 %, p = 0.97).

CONCLUSIONS

ICAC is seen on CT in nearly three-quarters of patients with LVO-AIS. Extent of ICAC has a U-shaped association with successful reperfusion, in part due to more frequent use of rescue interventions in patients with extensive ICAC.

Clinical comparison of aspiration to stentriever-mediated aspiration thrombectomy for M2 occlusions

OBJECTIVE

While revascularization for M2 occlusions is generally recommended and considered beneficial, the optimal approach (aspiration vs stentriever/combined) is less well defined in the literature. We sought to compare outcomes after thrombectomy with manual aspiration thrombectomy alone (MAT) or stentriever-mediated aspiration thrombectomy (SMAT) MATERIALS AND METHODS: To circumvent inter-operator technical variability, patients underwent thrombectomy for M2 occlusions by a single operator and were stratified by first pass approach: manual aspiration thrombectomy (MAT/aspiration alone) and stentriever-mediated manual aspiration thrombectomy (SMAT/combination). Efficacy outcomes included good reperfusion (mTICI score ≥2b) and a favorable 90-day functional outcome (mRS score of ≤2). Safety outcomes included 90-day mortality and symptomatic intracranial hemorrhage.

RESULTS

One hundred three patients were identified: 57 underwent MAT whereas 46 underwent SMAT. Good reperfusion (TICI 2b or greater) was comparable between groups (93.5 % vs. 87.7 %, P=0.33). The intracranial hemorrhage rate was higher with SMAT compared to MAT (13 % vs. 1.8 %, P=0.04). Puncture-to-recanalization time was longer in SMAT (34.4 vs. 19.9 minutes, P<0.001). In multivariable analysis, complete or good reperfusion was associated with shorter puncture-recanalization time (adjusted odds ratio [aOR], 0.85) or less total passes (aOR, 0.58), respectively. In a propensity score matched analysis of 66 patients with comparable baseline and technical efficiency, the safety outcomes were not different between SMAT and MAT groups.

CONCLUSIONS

SMAT compared with MAT did not result in an improved revascularization rate or functional outcome, while it was related to more hemorrhagic complications and mortality. Given cost and time savings with manual aspiration alone, this approach may be optimal as first line for M2 occlusions.

Success with incrementally faster times to endovascular therapy (SWIFT-EVT): A systematic review and meta-analysis

BACKGROUND

A major systematic review and meta-analysis assessing trial data through 2014 (the Highly Effective Reperfusion Evaluated in Multiple Endovascular Stroke Trials, HERMES) demonstrated that particularly over the initial six hours of acute ischemic stroke (AIS), rapid performance of endovascular therapy (EVT) markedly improves outcomes. The current analysis, Success with Incrementally Faster Times to EVT (SWIFT-EVT), aimed to provide an updated metric summarizing latest estimates for modified Rankin Scale (mRS) improvements accrued by streamlining time to EVT.

METHODS

A systematic review and meta-analysis was conducted using electronic databases. Eligible studies reported a time-benefit slope with times from AIS onset (or time last known normal) to EVT commencement; the predictor was onset-to-groin (OTG) time. Primary and secondary outcomes were 90-day functional independence (mRS 0-2) and 90-day excellent function (mRS 0-1), respectively.

RESULTS

Five studies were included. Results showed increased change of good outcome with each hour of pre-EVT time savings for mRS 0-2 for 0-270' (OR 1.25, 95 % CI 1.16-1.35, I2 40 %) and 271-360' time frame (1.22, 95 % CI 1.12-1.33, I2 58 %). For the studies assessing mRS 0-1, estimates were found appropriate for both the 0-270' time frame (OR 1.34, 95 % CI 1.19-1.51, I2 27 %) and the 271-360' time frame (OR 1.20, 95 % CI 1.03-1.38, I2 60 %).

CONCLUSIONS

Each hour saved from AIS onset to EVT start is associated with a 22-25 % increased odds of achieving functional independence, a useful metric to inform patient-specific and systems planning decisions.

Longitudinal outcomes of ischemic versus hemorrhagic stroke: Differences may impact future trial design

OBJECTIVES

Patients with intracerebral hemorrhage (ICH) are more likely to present with severe symptoms than those with ischemic stroke (IS); however, the way in which long-term outcomes differ between groups is less clear. Given that the tissue surrounding ICH is not always irreversibly infarcted, it may have the potential to recover more fully over time. Understanding the differences in expected outcome severity is critical in order to prognosticate and to determine appropriate outcome measures when designing clinical trials.

MATERIALS AND METHODS

We used our prospectively collected stroke registry to identify and follow a cohort of 300 patients with ICH and 300 patients with IS, matched by age, sex, lesion size, location, and admission date. Paired t-tests were used to compare modified Rankin Scores (mRS) between groups at hospital discharge, 90-day, and >12-month follow-up time points.

RESULTS

Not surprisingly, patients with ICH had worse discharge mRS scores compared to individuals with IS (4.20 (SD 0.09) versus 3.42 (SD 0.08)). However, rather than improving, the long-term outcomes remained significantly worse for ICH patients compared to their IS matches (4.02 (SD 0.15) versus 2.89 (SD 0.14) at 90 days, and 4.32 (SD 0.20) versus 3.16 (SD 0.22) at >12 months (p < 0.001 for all analyses)).

CONCLUSIONS

This study longitudinally followed matched cohorts of patients with ICH and IS, confirming that outcomes for those with ICH remain significantly worse over time. Results allow for better long-term prognostication, illustrate the need for further intervention trials to improve outcomes, and inform the development of evidence-based endpoints.

The safety and efficacy of NeVa mechanical thrombectomy device in acute ischemic stroke: A systematic review and meta-analysis

BACKGROUND

Recent favorable cohort studies on endovascular therapy for ischemic stroke have predominantly utilized NeVa thrombectomy (NeVaTM) stent retrievers. We carried out a systematic review and meta-analysis to investigate the efficacy and safety of this second-generation stent retriever in acute ischemic stroke patients.

METHOD

We conducted the study according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The electronic databases of PubMed, Embase, and Scopus were searched until 26 November 2023 and was updated on August 1, 2024.

RESULTS

This meta-analysis systematically investigated 11 studies with a total of 805 patients suffering from ischemic stroke. The mean age of participants across the studies ranged from 65 to 77 years with a male preponderance of 50.16 %. While ten studies reported on the etiology of strokes, some studies reported the risk factors such as hypertension, dyslipidemia, diabetes, history of coronary artery disease, and previous stroke. The results of our study indicate that the all-hemorrhagic complications rate was 0.32 (95 %CI: 0.18-0.45), while the complete arterial recanalization rate was 0.76 [95 %CI: 0.49-1.04]. The overall recanalization rate was found to be 0.97 [95 %CI: 0.94-1.00]. Moreover, the postoperative hemorrhage rate was 0.28 [95 %CI: 0.14-0.41], while the repeated re-thrombosis rate was 0.01 [95 %CI: -0.01-0.03]. Lastly, the vasospasm rate was calculated to be 0.09 [95 %CI: -0.03-0.21].

CONCLUSION

NeVa™ is a safe option capable of achieving a high rate of recanalization and functional independence.

ABBREVIATIONS

PRISMA, Preferred Reporting Items for Systematic Reviews and Meta-Analyses; PROSPERO, International Prospective Register of Systematic Reviews; NeVa™, NeVa Thrombectomy; ICH, Intracranial Hemorrhage; mTICI, modified Thrombolysis in Cerebral Infarction; mRS, modified Rankin Scale; ACA, Anterior Cerebral Artery; MCA, Middle Cerebral Artery; PCA, Posterior Cerebral Artery; ICA, Internal Carotid Artery; NIHSS, National Institutes of Health Stroke Scale.

A retrospective analysis of a newly proposed imaging-etiologic classification for acute ischemic stroke with large vascular occlusion based on MRI and pathogenesis

Background

Endovascular treatment (EVT) has emerged as the preferred initial therapeutic option for acute ischemic stroke (AIS) with large vascular occlusion (LVO). To facilitate more targeted EVT interventions, we propose a novel imaging-etiologic classification system derived from a comprehensive analysis of preoperative MRI and pathogenesis in AIS patients.

Methods

From June 2020 to December 2021, a retrospective analysis was conducted on 184 consecutive AIS patients who underwent preoperative MRI and subsequent EVT at the Henan Provincial Cerebrovascular Hospital Stroke Center. Patients' medical histories were comprehensively reviewed. According to MRI, anterior circulation infarction (ACI) and posterior circulation infarction (PCI) were divided into four groups respectively (A-D & a-d). Three types (1-3) of etiology were identified based on pathogenesis. The types were respectively evaluated by screening test with intra-operative finding of EVT.

Results

Our imaging-etiologic classification achieved an overall positive rate of 90.2% (166/184) when compared to the gold standard. The screening test for each type demonstrated excellent validity (Youden's index ≥ 0.75) and reliability (Kappa ≥ 0.80).

Conclusion

The imaging-etiologic classification represents a simple yet comprehensive approach that can be readily applied in the management of AIS with LVO. It can rapidly and effectively locate the vascular occlusion, and reveal the pathogenesis.

Anticoagulation Therapy Timing in patients with Atrial Fibrillation after Acute and Chronic Subdural Haematoma (ATTAACH): a pilot randomised controlled trial

INTRODUCTION

Subdural haematomas (SDHs), acute or chronic, are common neurosurgical diagnoses. These problems can occur among patients requiring direct oral anticoagulation (DOAC) for atrial fibrillation. There are currently no guidelines regarding the optimal timing to resume anticoagulation for these patients after SDH. The objective of this study is to evaluate the feasibility of conducting a future large randomised controlled trial (RCT) evaluating the safety and efficacy of resuming DOACs early (ie, at 30 days) vs late (ie, at 3 months) for patients with atrial fibrillation following diagnosis of SDH.

METHODS AND ANALYSIS

This is a pilot, open-label, multicentre RCT that will enrol adults with newly diagnosed acute or chronic SDH with or without other intracranial bleeding who were receiving therapeutic anticoagulation with a DOAC as stroke prophylaxis for atrial fibrillation. Patients will be randomly allocated to resume a DOAC at standard dosing starting either days 30+7 or days 90±14. The primary outcomes for the pilot RCT are recruitment rate, protocol adherence and patient compliance with the randomly allocated interventions. Secondary outcomes are patient functional outcomes and safety and effectiveness outcomes, which will comprise key endpoints for the future planned RCT. This pilot RCT will provide important data to inform the feasibility of conducting a future, large RCT of early versus late resumption of DOACs for atrial fibrillation stroke prophylaxis in patients newly diagnosed with SDH. The future RCT will help inform management of a commonly encountered clinical dilemma with high associated morbidity and mortality.

ETHICS AND DISSEMINATION

This study has been approved by the research ethics board of record. It will be conducted in accordance with the Declaration of Helsinki, Good Clinical Practice guidelines and regulatory requirements. Informed consent will be obtained from eligible patients or substitute decision-makers. Data from this study will inform the design of future, larger RCTs.

TRIAL REGISTRATION NUMBER

NCT05472766.

Low body mass index patients have worse outcomes after mechanical thrombectomy

BACKGROUND

There is evidence that frailty is an independent predictor of worse outcomes after stroke. Similarly, although obesity is associated with a higher risk for stroke, there are multiple reports describing improved mortality and functional outcomes in higher body mass index (BMI) patients in a phenomenon known as the obesity paradox. We investigated the effect of low BMI on outcomes after mechanical thrombectomy (MT).

METHODS

We conducted a retrospective analysis of 231 stroke patients who underwent MT at an academic medical center between 2020-2022. The patients' BMI data were collected from admission records and coded based on the Centers for Disease Control and Prevention (CDC) obesity guidelines. Recursive partitioning analysis (RPA) in R software was employed to automatically detect a BMI threshold associated with a significant survival benefit. Frailty was quantified using the Modified Frailty Index 5 and 11.

RESULTS

In our dataset, by CDC classification, 2.6% of patients were underweight, 27.3% were normal BMI, 30.7% were overweight, 19.9% were class I obese, 9.5% were class II obese, and 10% were class III obese. There were no significant differences between these groups. RPA identified a clinically significant BMI threshold of 23.62 kg/m2. Independent of frailty, patients with a BMI ≤23.62 kg/m2 had significantly worse overall survival (P<0.001) and 90-day modified Rankin Scale (P=0.027) than patients above the threshold.

CONCLUSIONS

Underweight patients had worse survival and functional outcomes after MT. Further research should focus on the pathophysiology underlying poor prognosis in underweight MT patients, and whether optimizing nutritional status confers any neuroprotective benefit.

Tigertriever in the treatment of acute ischemic stroke with underlying intracranial atherosclerotic disease

BACKGROUND

The Tigertriever device offers a unique feature that enables gradual control of the radial expansion. We sought to evaluate the safety and efficacy of the Tigertriever device in patients with large vessel occlusion (LVO) and underlying intracranial atherosclerotic disease (ICAD). The patients were part of the TIGER trial.

METHODS

The presence of underlying ICAD was determined by a core imaging laboratory using CT angiography and digital subtraction angiography. The primary outcomes included successful reperfusion, puncture to reperfusion time, and complications associated with the use of the Tigertriever device. Patients underwent mechanical thrombectomy with the Tigertriever device for up to three passes, and alternative devices were employed for subsequent passes.

RESULTS

A total of 160 patients were enrolled in the TIGER trial, and 32 patients had ICAD. Among the patients with ICAD, 78% achieved successful reperfusion within three passes of the Tigertriever device, without requiring rescue therapy. Additionally, a first pass effect was observed in 46.8%. The median time from puncture to reperfusion was 22 minutes. There were no device-related complications. The National Institutes of Health Stroke Scale (NIHSS) score at 24 hours was significantly reduced, from an average of 17 at baseline to 8. At the 3 month follow-up, 50% of patients achieved a modified Rankin Scale score of ≤2.

CONCLUSION

Endovascular therapy (EVT) with the Tigertriever device for LVO in patients with underlying ICAD is effective and safe. When compared with historical data from other devices employed in similar cases, we observed a high rate of successful reperfusion, along with a shorter puncture to reperfusion time.

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.

The presence of a ghost infarct core is associated with fast core growth in acute ischemic stroke

INTRODUCTION

The overestimation of ischemic core volume by CT perfusion (CTP) is a critical concern in the selection of candidates for reperfusion therapy. This phenomenon is termed a ghost infarct core (GIC). Core growth rate (CGR) is an indicator of ischemic severity. We aimed to elucidate the association between GIC and CGR.

PATIENTS AND METHODS

Consecutive patients with acute ischemic stroke who underwent mechanical thrombectomy in our institute from March 2017 to July 2022 were enrolled. The initial ischemic core volume (IICV) was measured by pretreatment CTP, and the final infarct volume (FIV) was measured by diffusion-weighted imaging. A GIC was defined by IICV minus FIV > 10 ml. The CGR was calculated by dividing the IICV by the time from onset to CTP. Univariable analysis and a multivariable logistic regression model were used to evaluate the association between GIC-positive and CGR.

RESULTS

Of all 91 patients, 21 (23.1%) were GIC-positive. The GIC-positive group had higher CGR (14.2 [2.6-46.7] vs 4.8 [1.6-17.1] ml/h, p = 0.02) and complete recanalization (n = 15 (71.4%) vs 29 (41.4%), p = 0.02) compared to the GIC-negative group. On receiver-operating characteristic curve analysis, the optimal cutoff point of CGR to predict GIC-positive was 22 ml/h (sensitivity, 0.48; specificity, 0.85; AUC, 0.67). Multivariable logistic regression analysis showed that CGR ⩾ 22 ml/h (OR 6.44, 95% CI [1.59-26.10], p = 0.01) and complete recanalization (OR 3.72, 95% CI [1.14-12.08], p = 0.02) were independent predictors of GIC-positive.

CONCLUSIONS

A GIC was associated with fast CGR in acute ischemic stroke. Overestimation of the initial ischemic core may be determined by core growth speed.

Endovascular thrombectomy after anterior circulation large vessel ischemic stroke: an updated meta-analysis

BACKGROUND

Endovascular thrombectomy (EVT) has emerged as the established standard of care for the treatment of anterior circulation large-vessel occlusion (LVO). However, its benefits remain unclear in specific patient populations. Herein, we present an updated systematic review and meta-analysis aimed at thoroughly assessing the effectiveness and safety of combining EVT with medical treatment (MT) compared with MT alone.

METHODS

This systematic review was performed in accordance with the PRISMA guideline. The MEDLINE, Embase, and Cochrane databases were systematically searched to identify relevant articles published until December 30, 2023. The inclusion criteria restricted articles to randomized clinical trials (RCTs). We pooled odds ratios (OR) and their respective 95% confidence intervals (CIs).

RESULTS

Fifteen RCTs involving 3897 patients were included in the study. EVT plus MT was associated with a significant reduction in disability at 90 days (OR = 1.91, [1.61-2.26]), improved functional independence (modified Rankin Scale [mRS] 0-2) (OR = 2.19 [1.81-2.64]), excellent functional outcomes (mRS 0-1) (OR = 2.37, [1.45-3.87]), improved independent ambulation (mRS 0-3) (OR = 2.17, [1.75-2.69]), and higher rates of partial/complete recanalization (OR = 2.18, [1.66-2.87] compared with EVT. Efficacy outcomes for both large and small infarct cores were statistically favorable following EVT. Safety outcomes showed comparable rates, except for intracerebral and subarachnoid hemorrhage, which favored MT alone.

CONCLUSION

This meta-analysis supports the use of EVT plus MT as the standard of care for acute ischemic stroke patients with LVO of any infarct core size, as it offers substantial improvements in functional outcomes and recanalization. Safety considerations, particularly the risk of hemorrhage, warrant careful patient selection. These findings provide valuable insights for optimizing stroke management protocols and enhancing patient outcomes.

Minor strokes: Addressing the challenges of recanalization therapies and secondary prevention

Minor strokes, which account for about 50 % of all ischemic strokes are not necessarily benign and carry a substantial risk of long-term disability. Due to persisting uncertainties regarding optimal recanalization strategies mild strokes may represent a therapeutical challenge for clinicians. The aim of this review is to provide an overview of the current state of knowledge and questions remaining to be answered.

High Hypoperfusion Intensity Ratio Is Independently Associated with Very Poor Outcomes in Large Ischemic Core Stroke

BACKGROUND

Recent advances have highlighted the efficacy of endovascular thrombectomy (EVT) in patients with large ischemic core stroke, yet a significant portion still experience very poor outcomes, defined as a 90-day modified Rankin Score (mRS) of 5-6. This study aims to investigate the hypoperfusion intensity ratio (HIR) as a prognostic imaging parameter for these outcomes.

METHODS

In a multicenter retrospective cohort study, data from consecutive patients undergoing EVT for acute ischemic stroke with large vessel occlusion (AIS-LVO) at two comprehensive stroke centers were analyzed. The study included patients with an Alberta Stroke Program Early CT Score (ASPECTS) of 5 or less and utilized pretreatment perfusion imaging to calculate HIR. The primary outcome was very poor outcomes (90 days mRS 5-6).

RESULTS

Among 102 patients included, 59 (57.8%) had very poor outcome (90 days mRS 5-6). Multivariable logistic regression analysis adjusting for multiple covariates including admission National Institutes of Health Stroke Scale (NIHSS) and EVT revealed that higher admission NIHSS (adjusted odds ratio [aOR] 1.224, 95% CI 1.089-1.374, p = 0.001) and HIR (aOR per 0.1 incremental change, 1.34, 95% CI 1.02-1.82, P = 0.042) were independently associated with very poor outcomes.

CONCLUSION

This study demonstrates that admission NIHSS and HIR are independently associated with very poor outcome (90 days mRS 5-6) in patients with large ischemic core strokes. These findings highlight the importance of collateral status and perfusion imaging in predicting outcomes in this patient population, suggesting a potential role for HIR in the triage and management of large core stroke patients.

Utility of automated CT perfusion software in acute ischemic stroke with large and medium vessel occlusion

BACKGROUND

Early diagnosis of large vessel occlusion (LVO) in acute stroke often requires CT angiography (CTA). Automated CT perfusion (CTP) software, which identifies blood flow abnormalities, enhances LVO diagnosis and patient selection for endovascular thrombectomy (EVT). This study evaluates the sensitivity of automated CTP images in detecting perfusion abnormalities in patients with acute ischemic stroke (AIS) and LVO or medium vessel occlusion (MeVO), compared to CTA.

METHODS

We screened acute ischemic stroke patients presenting within 24 h who underwent CT, CTA, and CTP as per institutional protocol. RAPID AI software processed CTP images, while neuroradiologists reviewed CTA for intracranial arterial occlusions. Sensitivity, specificity, and accuracy of automated CTP maps in detecting occlusions were assessed.

RESULTS

Of 790 screened patients, 31 were excluded due to lack of RAPID CTP data or poor-quality scans, leaving 759 for analysis. The median age was 71 years (IQR: 61-81), with 47% female. Among them, 678 had AIS, and 81 had AIS ruled out. CTA identified arterial occlusion in 562 patients (74%), with corresponding CTP abnormalities in 537 patients (Tmax > 6 sec). In the 197 without occlusion, CTP was negative in 161. Automated CTP maps had a sensitivity of 95.55% (CI 95: 93.50-97.10%), specificity of 81.73% (CI 95: 75.61-86.86%), negative predictive value of 98.22% (CI 95: 97.39-98.79%), positive predictive value of 63.54% (CI 95: 56.46-70.09%), and overall accuracy of 85.18% (CI 95: 82.45-87.64%).

CONCLUSIONS

Automated CTP maps demonstrated high sensitivity and negative predictive value for LVOs and MeVOs, suggesting their usefulness as a rapid diagnostic tool, especially in settings without expert neuroradiologists.

Validation of Prognostic Scales for Functional Outcome in Ischemic Stroke Patients Treated with Intravenous Thrombolysis in a Rural Setting

INTRODUCTION

Early prediction of functional outcome after rtPA helps clinicians in prognostic conversations with stroke patients and their families. Three prognostic tools have been developed in this regard: DRAGON, MRI-DRAGON, and S-TPI scales. These tools, all performing with comparable accuracy, have been internally and externally validated in tertiary care centers. However, their performance in rural areas remains uncertain. This study addresses this gap in the literature by evaluating the effectiveness of those prognostic tools in stroke patients treated in a rural area of the Midwest.

METHODS

We conducted a retrospective study of stroke patients treated with thrombolytics at Southern Illinois Healthcare Stroke Network from July 2017 to June 2024. Data on demographics, clinical presentations, laboratory values, neuroimaging, and stroke metrics were collected. Modified Rankin Scale (mRS) at 1 month, classified into good (mRS ≤2) and poor (mRS ≥5) outcomes were noted. DRAGON and MRI-DRAGON scores were calculated. S-TPI model was built. Area under the receiver operating characteristic curve (AUC) with its 95% confidence interval was calculated for each prognostic model.

RESULTS

A total of 279 patients were included in this study. Of those, 43% (n = 119) were male. Median age (interquartile range [IQR]) was 69 (57-80) years. NIHSS at presentation (IQR) was 7 (4-13). 12% of the cohort (n = 34) had posterior circulation stroke. At 1 month, 66% of patients (n = 185) had mRS ≤2, whereas 14% of patients (n = 39) had mRS ≥5. MRI-DRAGON showed the highest accuracy in predicting both good (AUC = 0.86, 95% CI: 0.81-0.90) and poor outcomes (AUC = 0.84, 95% CI: 0.76-0.91). DRAGON also demonstrated high accuracy for good (AUC = 0.85, 95% CI: 0.80-0.89) and poor (AUC = 0.82, 95% CI: 0.75-0.90) outcomes. Conversely, in our population, the S-TPI model had the lowest accuracy for good (AUC = 0.56, 95% CI: 0.49-0.63) and poor (AUC = 0.68, 95% CI: 0.61-0.76) outcomes.

CONCLUSION

Among the available grading scores, MRI-DRAGON score can be considered the more accurate short-term prognostic tool for stroke patients treated with rtPA in the rural setting.

Cerebral blood flow from arterial spin labeling as an imaging biomarker of outcome after endovascular therapy for ischemic stroke

Arterial spin labeling (ASL) is a contrast agent-free magnetic resonance imaging (MRI) technique to measure cerebral blood flow (CBF). We sought to investigate effects of CBF within the infarct on outcome and risk of hemorrhagic transformation (HT). In 111 patients (median age: 74 years, 50 men) who had undergone mechanical thrombectomy (MT) for ischemic stroke of the anterior circulation (median interval: 4 days between MT and MRI), post-stroke %CBF difference from pseudo-continuous ASL was calculated within the diffusion-weighted imaging (DWI)-positive infarct territory following lesion segmentation in relationship to the unaffected contralateral side. Functional independence was defined as a modified Rankin Scale (mRS) of 0-2 at 90 days post-stroke. %CBF difference, pre-stroke mRS, and infarct volume were independently associated with functional independence in a multivariate regression model. %CBF difference was comparable between patients with and without HT. A subcohort of 10 patients with decreased infarct-CBF despite expanded Treatment in Cerebral Infarction (eTICI) 2c or 3 recanalization was identified (likely related to the no-reflow phenomenon). Outcome was significantly worse in this group compared to the remaining cohort. In conclusion, ASL-derived %CBF difference from the DWI-positive infarct territory independently predicted functional independence, but %CBF difference was not significantly associated with an increased risk of HT.

Deep Learning Denoising Improves CT Perfusion Image Quality in the Setting of Lower Contrast Dosing: A Feasibility Study

BACKGROUND AND PURPOSE

Considering recent iodinated contrast shortages and a focus on reducing waste, developing protocols with lower contrast dosing while maintaining image quality through artificial intelligence is needed. This study compared reduced iodinated contrast media and standard dose CTP acquisitions, and the impact of deep learning denoising on CTP image quality in preclinical and clinical studies. The effect of reduced X-ray mAs dose was also investigated in preclinical studies.

MATERIALS AND METHODS

Twelve swine underwent 9 CTP examinations each, performed at combinations of 3 different x-ray (37, 67, and 127 mAs) and iodinated contrast media doses (10, 15, and 20 mL). Clinical CTP acquisitions performed before and during the iodinated contrast media shortage and protocol change (from 40 to 30 mL) were retrospectively included. Eleven patients with reduced iodinated contrast media dosages and 11 propensity-score-matched controls with the standard iodinated contrast media dosages were included. A residual encoder-decoder convolutional neural network (RED-CNN) was trained for CTP denoising using k-space-weighted image average filtered CTP images as the target. The standard, RED-CNN-denoised, and k-space-weighted image average noise-filtered images for animal and human studies were compared for quantitative SNR and qualitative image evaluation.

RESULTS

The SNR of animal CTP images decreased with reductions in iodinated contrast media and milliampere-second doses. Contrast dose reduction had a greater effect on SNR than milliampere-second reduction. Noise-filtering by k-space-weighted image average and RED-CNN denoising progressively improved the SNR of CTP maps, with RED-CNN resulting in the highest SNR. The SNR of clinical CTP images was generally lower with a reduced iodinated contrast media dose, which was improved by the k-space-weighted image average and RED-CNN denoising (P < .05). Qualitative readings consistently rated RED-CNN denoised CTP as the best quality, followed by k-space-weighted image average and then standard CTP images.

CONCLUSIONS

Deep learning-denoising can improve image quality for low iodinated contrast media CTP protocols, and could approximate standard iodinated contrast media dose CTP, in addition to potentially improving image quality for low milliampere-second acquisitions.

Early access programs for medical devices in France: Overview of recent reforms and outcomes (2015-2022)

The medical technology sector is characterised by a constant influx of innovations with the potential to revolutionise patient care. In France, there are several pathways for medical devices to enter the market, from diagnosis-related group tariffs to reimbursement lists. However, traditional regulatory pathways can delay market access for innovative technologies. In response, France has established Early Access Programs to expedite patient access to medical devices. This paper looks at three of these Early Access Programs for medical devices. Innovation Funding, introduced in its final version in 2015, provides temporary coverage for innovative devices and facilitates data collection for informed funding decisions. Transitional Coverage (PECT), established in 2021, targets CE-marked devices for rare or serious conditions. Transitional coverage for digital health applications (PECAN), introduced in 2022, covers digital medical devices, either therapeutic or for patient monitoring. Innovation funding has been granted to 16 technologies out of 35 applications (46%) since 2015. 6 technologies out of 11 (64%) applications benefit from PECT. PECAN, in its first year, has granted a telemonitoring solution with a favourable opinion. The French experience could provide valuable lessons for the development of a harmonised European framework to ensure that innovative medical technologies benefit those who need them, while maintaining high safety standards.

Optimal Catheter Selection for Patients with Acute Stroke with Type III Aortic Arch Based on Magnetic Resonance Angiography Road Mapping of the Para-Aortic Transfemoral Access Route Before Mechanical Thrombectomy

BACKGROUND

Although mechanical thrombectomy for acute ischemic stroke has a high recanalization rate, procedurally challenging lesions remain in approximately 10% of the cases. Type III aortic arches, due to their anatomical configuration, are a fundamental problem impacting this procedure. This study aimed to determine whether optimal catheter selection for type III aortic arches, using magnetic resonance angiography (MRA)-based road mapping of the para-aortic transfemoral access route, reduces the time required for mechanical thrombectomy.

METHODS

We retrospectively evaluated 203 consecutive patients who underwent mechanical thrombectomy at multiple centers between April 2018 and July 2022. 23 patients were diagnosed with a type III aortic arch using MRA-based road mapping performed to visualize the para-aortic access route before neuro-interventional procedures. Among the 23 patients with type III aortic arches, 10 received a Simmons-type catheter (initial Simmons group) and 13 received a JB-2-type catheter (initial JB-2 group) as their first inner catheter. The time required for mechanical thrombectomy was compared between the groups.

RESULTS

Compared with the initial JB-2 group, the initial Simmons group exhibited a significantly shorter "puncture-to-recanalization time" (105 vs. 53 minutes, P = 0.009) and "door-to-recanalization time" (164 vs. 129 minutes, P = 0.032).

CONCLUSIONS

Optimal catheter selection by identifying the aortic arch before mechanical thrombectomy using MRA-based road mapping effectively reduced the mechanical thrombectomy time. This suggests that even in type III aorta cases, appropriate catheter selection may shorten the mechanical thrombectomy time and improve acute ischemic stroke prognosis.

Energy barriers govern catheter herniation during endovascular procedures: a 2.5D vascular flow model analysis

Endovascular procedures rely on navigating guidewires, catheters and other devices through tortuous vasculature to treat disease. A critical challenge in these procedures is catheter herniation, in which the device deviates from its intended path, often irrecoverably. To elucidate the mechanics of herniation, we developed a physical flow model of the aortic arch that enables direct measurement of device curvature during experimentally simulated neuroendovascular procedures conducted from an upper arterial access. Combined with measurements of initial, unstressed device shapes and flexural rigidities, the method enables the experimental estimation of the device bending energies during these simulated procedures. Characteristic energy profiles revealed distinct stages in both herniation and successful navigation, governed by the interplay between device properties and vascular anatomy. A deterministic progression from successful navigation to herniation was identified, with catheter systems following paths determined by measurable energy barriers. Increasing guidewire stiffness or decreasing catheter stiffness reduced the energy barrier for successful navigation while increasing that for herniation. This framework enables the prediction of endovascular herniation risk and offers unique insight into improved device design and clinical decision-making.

Association of Systemic Inflammatory Response Index and Neutrophil-to-Lymphocyte Ratio on Unfavorable Functional Outcomes in Acute Ischemic Stroke Patients After Endovascular Therapy

BACKGROUND

Inflammatory markers for the prognosis of acute ischemic stroke (AIS) with endovascular therapy remain unclear. The purpose of this study was to investigate the association between the systemic inflammatory response index (SIRI) and neutrophil-to-lymphocyte ratio (NLR) with unfavorable functional outcomes at 90-day in individuals of AIS who underwent endovascular therapy.

METHODS

A total of 128 AIS patients who had endovascular therapy were enrolled from the Nanjing Stroke Registry between September 2019 and November 2022. Peripheral venous blood was collected from patients within 24 h of admission for information on the following parameters: neutrophil count, lymphocyte count, and monocyte count. Then, the SIRI and NLR values were calculated and the association among SIRI, NLR, and modifled Rankin Scale scores 90 days after endovascular therapy was examined via univariate and multivariate logistic analyses. Receiver operating characteristic curves were utilized to determine the best threshold for SIRI and NLR in predicting negative neurological outcomes following endovascular treatment for patients with AIS.

RESULTS

A total of 128 participants were evaluated, among which 50% had unfavorable outcomes. Linear regression analysis showed that the best threshold for SIRI was >1.407 (odds ratio = 1.265; 95% confidence interval, 1.071-1.493; P = 0.006), and for NLR it was >5.347 (odds ratio = 1.088; 95% confidence interval, 1.007-1.175; P = 0.033). These results revealed NLR and SIRI as significant predictors of unfavorable outcomes at 90 days. The area under the curve for SIRI and NLR in predicting 90-day adverse outcomes was 0.643 and 0.609, respectively.

CONCLUSIONS

Higher SIRI and NLR levels at admission may lead to unfavorable outcomes at 90 days for AIS patients with endovascular therapy.

A Narrative Review of Interhospital Transfers for Intracerebral Hemorrhage

Of the 750,000 strokes in the United States every year, 15% patients suffer from hemorrhagic stroke. Intracerebral hemorrhage (ICH) is a subtype of hemorrhagic stroke. Despite advances in acute management, patients with hemorrhagic stroke continue to suffer from high mortality and survivors suffer from multidomain impairments in the physical, cognitive, and mental health domains which could last for months to years from their index stroke. Long-term prognosis after ICH is critically dependent on the quality and efficacy of care a patient receives during the acute phase of care. With ongoing care consolidation in stroke systems of care, the number of ICH patients who need to undergo interhospital transfers (IHTs) is increasing. However, the associations between IHT and ICH outcomes have not been well described in literature. In this review, we describe the epidemiology of IHT for ICH, the relationship between IHT and ICH patient outcomes, and proposed improvements to the IHT process to ensure better long-term patient outcomes. Our review indicates that evidence regarding the safety and benefit of IHT for ICH patients is conflicting, with some studies reporting poorer outcomes for transferred patients compared to direct admissions via emergency rooms and other studies showing no effect on outcomes. The American Heart Association guidelines for ICH provide recommendations for timely blood pressure control and anticoagulation reversal to improve patient outcomes. The American Heart Association stroke systems of care guidelines provide recommendations for transfer agreements and but do not provide details on how patients should be managed while undergoing IHT. Large, prospective, and multicenter studies comparing outcomes of IHT patients to direct admissions are necessary to provide more definitive guidance to optimize IHT protocols and aid clinical decision-making.

Temporal trends of sex differences in acute reperfusion therapy and early outcomes of acute ischemic stroke in South Korea: 10-year analysis of the nationwide stroke registry

BACKGROUND

Sex differences in stroke outcomes are notable, with women experiencing higher incidence rates, greater disability-adjusted life years, and poorer recovery compared to men, even after adjusting for age and comorbidities. Despite the disproportionate burden in women, studies have reported that women are less likely to receive appropriate stroke treatment than men.

AIM

This study investigated temporal trends of sex differences in acute reperfusion therapy and early outcomes in patients with acute ischemic stroke over 10 years in South Korea.

METHODS

A retrospective analysis of Korean Stroke Registry included patients with acute ischemic stroke from 2012 to 2021. The study outcomes were the temporal trends of acute reperfusion therapy and early outcomes over 10 years in men and women, respectively. In addition, this study analyzed the temporal trends of sex differences in these parameters during the same period. Early outcomes include the proportions of favorable functional outcomes at discharge, discharge patterns, and in-hospital mortality.

RESULTS

A total of 93,692 patients (68.4 years, 40.1% women) with acute ischemic stroke were finally enrolled. Women had a higher age at stroke onset, a higher prevalence of atrial fibrillation, and more severe strokes than men. Women had lower proportion of favorable functional outcomes at discharge and higher proportion of in-hospital mortality compared to men each year. The proportion of patients who received intravenous thrombolysis was lower or similar in women compared to men in most years, and the proportion of patients who received endovascular thrombectomy did not significantly differ between sexes annually. Sex differences in acute reperfusion therapy remained unchanged over 10 years.

CONCLUSION

Women have received acute reperfusion therapy at similar or lower rates than men and experienced poorer outcomes, despite having more stroke risk factors and often more severe strokes.

Is Thrombectomy Effective for Large Vessel Occlusion Stroke Patients with Mild Symptoms? Meta-Analysis and Trial Sequential Analysis

BACKGROUND

Endovascular treatment (EVT) is an established method for managing large vessel occlusion (LVO), but its efficacy in patients with mild stroke (National Institutes of Health Stroke Scale [NIHSS] score < 6) remains debated. Given the clinical problem of early neurological deterioration in approximately 10% of mild stroke patients, understanding the role of EVT in managing these patients is crucial. Our objective was to perform a meta-analysis with trial sequential analysis (TSA) focusing on mild stroke patients with LVO to determine whether EVT offers better outcomes than best medical therapy alone.

METHODS

A comprehensive search of PubMed, Cochrane, and Embase databases up to 12 December 2023 identified 14 retrospective and prospective cohort studies, including a total of 4436 patients with NIHSS scores less than 6 and presenting with LVO. Studies were categorized into crossover and non-crossover groups to prevent overestimation of the treatment effect. In the crossover group, patients initially treated with BMT were moved to EVT upon clinical deterioration. In the non-crossover group, patients remained in their initially assigned treatment. Meta-analysis and data extraction followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The primary outcome was achieving an excellent functional outcome, defined as a modified Rankin scale (mRS) score of 0-1 at 3 months. Secondary outcomes included good (mRS 0-2) and favorable (mRS 0-3) functional outcomes. Safety outcomes were symptomatic intracerebral hemorrhage (sICH) and mortality at 3 months.

RESULTS

In the crossover group, EVT did not significantly improve excellent functional outcomes, and TSA results were inconclusive. Conversely, in the non-crossover group, EVT significantly improved the excellent functional outcome rates at 3 months (65.0% vs. 53.7%; OR 1.62; 95% CI 1.13 to 2.32), supported by TSA. EVT increased the risk of sICH in both crossover and non-crossover groups, while mortality rates did not significantly differ between EVT and BMT groups.

CONCLUSIONS

Our research indicates that thrombectomy may not significantly help mild stroke patients in recovering functional status and could increase the risk of sICH. The disparity in results between crossover and non-crossover studies highlights the critical need for the prompt identification of patients at risk of early neurological deterioration to minimize negative outcomes. Additional randomized controlled trials are essential to optimize the application of EVT in this patient population.

Early dual antiplatelet therapy in patients with minor ischemic stroke after intravenous thrombolysis

OBJECTIVES

Minor stroke is defined by a score of 5 or less on the National Institutes of Health Stroke Scale (NIHSS). Prior trials have shown efficacy of short term dual antiplatelet therapy (DAPT) in secondary prevention of stroke among patients with transient ischemic attack (TIA) or minor ischemic stroke, but no randomized clinical trials have studied this benefit after intravenous thrombolysis (IVT). Our aim was to investigate the safety of DAPT within 90 days after IVT in patients with acute minor ischemic stroke.

PATIENTS AND METHODS

We reviewed medical records of patients older than 18 years that received IVT between January 2015 and December 2022. Patients had a diagnosis of acute minor stroke or averted stroke (complete recovery and negative image on follow-up). Single or dual antiplatelet treatment was started 24 hours after thrombolysis according to the physician's judgment. Patients were divided in two groups: single and dual antiplatelet therapy. We assessed clinical outcome using the modified Rankin scale (mRS), symptomatic intracranial hemorrhage (SICH) and mortality at 90 days.

RESULTS

Fifty-three patients met the inclusion criteria, 68% men aged 64±16,5 years. Seventy five percent had an ischemic stroke and 25% had an averted stroke. Median door-to-needle time was 50 minutes. Fifty one percent were in the single antiplatelet group and 49% in the dual antiplatelet therapy group. There were no differences in demographic and clinical characteristics between groups. The 90-day mRS did not show significant difference between groups. No patients had SICH nor died during follow-up. One patient in the single antiplatelet group had stroke recurrence.

CONCLUSIONS

Dual antiplatelet therapy after IVT with rtPA for acute minor ischemic stroke appears not to increase the risk of bleeding and mortality compared to single antiplatelet therapy in the first three months after the event. This is the first study to assess this subject in a Latin American population.

Big data analysis of endovascular treatment for acute ischemic stroke: a study based on bibliometric analysis

BACKGROUND

 While bibliometric analyses are prevalent in the medical field, few have focused on ther endovascular treatment for acute ischemic stroke (AIS).

OBJECTIVE

 To employ big data analysis to examine the research status, trends, and hotspots in endovascular treatment for AIS.

METHODS

 We conducted a comprehensive search using the Web of Science (WOS) database to identify relevant articles on the endovascular treatment for AIS from 1980 to the present. We used various tools for data analysis, including an online platform (https://bibliometric.com/app), the Citespace software, the Vosviewer software, and the ArcMap software, version 10.8. A number of bibliometric indicators were collected and analyzed, such as publication date, country where the studies were conducted, institutions to which the authors were affiliated, authors, high-frequency keywords, cooperative relationship etc. RESULTS:  A total of 5,576 articles were retrieved. A substantial increase in the number of articles occurred after 2010. High-frequency keywords included terms such as large vessel occlusion, reperfusion, outcome, and basilar artery occlusion. Among the top 10 most productive authors, Raul G. Nogueira ranked first, with 136 published articles. Among the journals, The New England Journal of Medicine ranked first, with 5,631 citations. The United States has the closest collaborative ties with other nations.

CONCLUSION

 In the present study, we found that the reports of endovascular treatment for AIS gradually increased after 2010. Among them, Raul G. Nogueira was the most productive author in this field. The New England Journal of Medicine was the most cited, and it had the greatest impact. The Multicenter Randomized Clinical Trial of Endovascular Treatment of Acute Ischemic Stroke in the Netherlands (MR CLEAN) trial study was the most cited, and it was a landmark study. There are many interesting studies on endovascular treatment for AIS, such as ischemic penumbra, collateral circulation, bridging therapy etc.

Infarct density defined by ADC threshold is associated with long-term functional outcome after endovascular thrombectomy

OBJECTIVES

Endovascular thrombectomy (EVT) dramatically improves clinical outcomes, but the reduction in final infarct volume only accounts for 10-15 % of the treatment benefit. We aimed to develop a novel MRI-ADC-based metric that quantify the degree of tissue injury to test the hypothesis that it outperforms infarct volume in predicting long-term outcome.

MATERIALS AND METHODS

A single-center cohort consisted of consecutive acute stroke patients with anterior circulation large vessel occlusion, successful recanalization via EVT (mTICI ≥2b), and MRI of the brain between 12 h and 7 days post-EVT. Imaging was processed via RAPID software. Final infarct volume was based on the traditional ADC <620 threshold. Logistic regression quantified the association of lesion volumes and good outcome (90-day modified Rankin Scale ≤2) at a range of lower ADC thresholds (<570, <520, and <470). Infarct density was calculated as the percentage of the final infarct volume below the ADC threshold with the greatest effect size. Univariate and multivariate logistic regression quantified the association between imaging/clinical metrics and functional outcome.

RESULTS

120 patients underwent MRI after successful EVT. Lesion volume based on the ADC threshold <470 had the strongest association with good outcome (OR: 0.81 per 10 mL; 95 % CI: 0.66-0.99). In a multivariate model, infarct density (<470/<620 * 100) was independently associated with good outcome (aOR 0.68 per 10 %; 95 % CI: 0.49-0.95), but final infarct volume was not (aOR 0.98 per 10 mL; 95 % CI: 0.85-1.14).

CONCLUSIONS

Infarct density after EVT is more strongly associated with long-term clinical outcome than infarct volume.

Adjunctive intra-arterial tenecteplase after successful endovascular thrombectomy in patients with large vessel occlusion stroke (POST-TNK): Study rationale and design

RATIONALE

Adjunct intra-arterial alteplase has been shown to potentially improve clinical outcomes in patients with large vessel occlusion (LVO) stroke who have undergone successful endovascular thrombectomy. Tenecteplase, known for its enhanced fibrin specificity and extended activity duration, could potentially enhance outcomes in stroke patients after successful reperfusion when used as an adjunct intra-arterial therapy.

AIM

To explore the safety and efficacy of intra-arterial tenecteplase after successful endovascular thrombectomy in patients with LVO stroke.

SAMPLE SIZE

To randomize 498 participants 1:1 to receive intra-arterial tenecteplase or no intra-arterial adjunctive thrombolysis therapy.

METHODS AND DESIGN

An investigator-initiated, prospective, randomized, open-label, blind-endpoint multicenter clinical trial. Eligible patients with anterior circulation LVO stroke presenting within 24 h from symptom onset (time last known well) and excellent to complete reperfusion (expanded Thrombolysis In Cerebral Infarction (eTICI) scale 2c-3) at endovascular thrombectomy are planned to be randomized.

OUTCOMES

The primary outcome is freedom from disability (modified Rankin Scale, mRS, of 0-1) at 90 days. The primary safety outcomes are mortality through 90 days and symptomatic intracranial hemorrhage within 48 h.

DISCUSSION

The POST-TNK trial will evaluate the efficacy and safety of intra-arterial tenecteplase in patients with LVO stroke and excellent to complete reperfusion.

Value of the red blood cell distribution width (RDW) and neutrophil lymphocyte ratio (NLR) in the prediction of functional recovery and 3-month mortality following endovascular treatment for acute anterior circulation ischemic stroke

Objectives

The red blood cell distribution width (RDW) and neutrophil to lymphocyte ratio (NLR) have been linked to poor prognosis in patients with ischaemic stroke. However, no study has yet evaluated the prognostic role of RDW and NLR, or their combined effect on reperfusion in patients with endovascularly-treated acute ischaemic stroke. This study therefore aimed to analyse the impact of RDW and NLR on poor functional outcomes and failed reperfusion following endovascular treatment in patients with acute anterior circulation ischaemic stroke.

Methods

A total of 275 patients with acute anterior circulation ischaemic stroke treated endovascularly between 2015 and 2018 were enrolled in this study. The relationships between RDW, NLR, and poor outcomes were analysed using univariate and multivariate logistic regression models and receiver operating characteristic (ROC) curve analysis. The Youden Index was applied to determine the cut-off value.

Results

Multivariate logistic regression analysis identified RDW (p = 0.015) and NLR (p = 0.015) as independent predictors of mortality at the 3rd month. ROC curve analysis of RDW revealed a cutoff value of 14.25 (p = 0.009) for poor clinical outcomes (modified Rankin scale [mRS] 3-6). Similarly, a cutoff value of 14.25 was found for mortality prediction (p = 0.003). The cutoff value for poor clinical outcome (mRS 3-6) in the NLR was determined as 5.93 (p = 0.003), whereas the cutoff value for mortality was set at 5.17 (p = 0.028). RDW also predicted failed reperfusion, with a cutoff value of 17.75 (p = 0.048).

Conclusions

High RDW and NLR upon admission were identified as independent indicators of mortality in endovascularly treated acute anterior circulation ischemic stroke patients. Furthermore, the RDW could potentially predict failed reperfusion.

Endovascular management of acute stroke

Stroke related to large vessel occlusion is a leading cause of disability and death worldwide. Advances in endovascular therapy to reopen occluded arteries have been shown to reduce patient disability and mortality. Expanded indications to treat patients with large vessel occlusion in the late window (>6 h from symptom onset), with basilar artery occlusion, and with large ischaemic core at presentation have enabled treatment of more patients with simplified imaging methods. Ongoing knowledge gaps include an understanding of which patients with large ischaemic infarct are more likely to benefit from endovascular therapy, the role of endovascular therapy in patients who present with low National Institutes of Health Stroke Scale scores or medium or distal vessel occlusion, and optimal management of patients with underlying intracranial atherosclerotic disease. As reperfusion can now be facilitated by intravenous thrombolysis, mechanical thrombectomy, or both, the development of cytoprotective or adjunctive drugs to slow infarct growth, enhance reperfusion, or decrease haemorrhagic risk has gained renewed interest with the hope to improve patient outcomes.

Cerebral perfusion in patients with unilateral internal carotid artery occlusion by dual post-labeling delays arterial spin labeling imaging

BACKGROUND

Global and regional cerebral blood flow (CBF) changes in patients with unilateral internal carotid artery occlusion (ICAO) are unclear when the dual post-labeling delays (PLD) arterial spin labeling (ASL) magnetic resonance imaging (MRI) technique is used. Manual delineation of regions of interest for CBF measurement is time-consuming and laborious.

AIM

To assess global and regional CBF changes in patients with unilateral ICAO with the ASL-MRI perfusion technique.

METHODS

Twenty hospitalized patients with ICAO and sex- and age-matched controls were included in the study. Regional CBF was measured by Dr. Brain's ASL software. The present study evaluated differences in global, middle cerebral artery (MCA) territory, anterior cerebral artery territory, and Alberta Stroke Program Early Computed Tomography Score (ASPECTS) regions (including the caudate nucleus, lentiform nucleus, insula ribbon, internal capsule, and M1-M6) and brain lobes (including frontal, parietal, temporal, and insular lobes) between ICAO patients and controls at PLD 1.5 s and PLD 2.5 s.

RESULTS

When comparing CBF between ICAO patients and controls, the global CBF in ICAO patients was lower at both PLD 1.5 s and PLD 2.5 s; the CBF on the occluded side was lower in 15 brain regions at PLD 1.5 s, and it was lower in 9 brain regions at PLD 2.5 s; the CBF in the contralateral hemisphere was lower in the caudate nucleus and internal capsule at PLD 1.5 s and in M6 at PLD 2.5 s. The global CBF in ICAO patients was lower at PLD 1.5 s than at PLD 2.5 s. The ipsilateral CBF at PLD 1.5 s was lower than that at PLD 2.5 s in 15 regions, whereas the contralateral CBF was lower at PLD 1.5 s than at PLD 2.5 s in 12 regions. The ipsilateral CBF was lower than the contralateral CBF in 15 regions at PLD 1.5 s, and in M6 at PLD 2.5 s.

CONCLUSION

Unilateral ICAO results in hypoperfusion in the global and MCA territories, especially in the ASPECTS area. Dual PLD settings prove more suitable for accurate CBF quantification in ICAO.

Spontaneous recanalization in acute large core ischemic stroke due to large vessel occlusion: a post-hoc analysis of the ANGEL-ASPECT trial

BACKGROUND

Previous studies have indicated that a subset of patients with acute ischemic stroke (AIS) due to large vessel occlusion (LVO) experience spontaneous recanalization (SR), but the prognosis and factors associated with SR in these individuals are not well characterized.

METHODS

We conducted a post hoc secondary analysis of the Study of Endovascular Therapy in Acute Anterior Circulation Large Vessel Occlusive Patients with a Large Infarct Core (ANGEL-ASPECT) trial. SR in the medical management group was defined as a modified arterial occlusive lesion (AOL) grade of 2 or 3 on computed tomography angiography (CTA) or magnetic resonance angiography (MRA) at 36 hours (±12 hours).

RESULTS

SR was detected in 67 out of 184 patients (36.4%) in the medical management (MM) group. The median age of patients was 67 years (interquartile range (IQR) 58-72), and 48 (71.6%) were male. The adjusted odds ratio (aOR) for 90-day modified Rankin Scale (mRS) score shift toward better outcomes of the MM with SR group vs the MM without SR group was 1.83, with marginally significant difference (95% confidence interval (CI) 0.992 to 3.36; P=0.053). No significant difference was found between the MM with SR group and EVT recanalization group (aOR 1.45; 95% CI 0.86 to 2.43; P=0.16) with similar findings in the inverse probability treatment weighting analysis (OR 0.85; 95% CI 0.49 to 1.48; P=0.57). Multivariable regression analysis showed that hypertension, atherothrombotic stroke and higher clot burden score were factors associated with SR.

CONCLUSIONS

SR in medically managed patients with acute large ischemic stroke caused by LVO was associated with good functional outcome. An improved understanding of SR patients may be helpful to develop therapeutic strategy in patients with large infarct due to LVO in anterior circulation.

TRIAL REGISTRATION NUMBER

NCT04551664.

pRESET thrombectomy device outcomes in patients with acute ischemic stroke: A systematic review and meta-analysis

BACKGROUND

Many devices are used to perform mechanical thrombectomy in the setting of large vessel occlusion acute ischemic stroke. We sought to evaluate the efficacy and safety of pRESET stent-retriever systems.

METHODS

We conducted a comprehensive systematic review and meta-analysis following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Relevant studies up to March 2024 were retrieved from PubMed, Scopus, Web of Science, and Embase databases.

RESULTS

A total of 8 papers met the inclusion/exclusion criteria comprising a total of 1140 participants (average age 72.4 ± 11.9, female percentage (50%). Preintervention intravenous thrombolysis was utilized in 46.5% (range 32.9-65.4) of patients, with a median National Institute of Health Stroke Scale at presentation of 15 (range 0-38). The middle cerebral artery was the most commonly affected artery, with a prevalence of 76.4% (range 62.8-100). The pRESET stent-retriever systems demonstrated a first-passing effect rate of 53.4% [95% confidence interval [CI] 44.8; 61.7] and a final thrombolysis in cerebral infarction 2b-3 grade rate of 90.41% [95% CI 82.13; 95.08]. Ninety-day modified Rankin Scale (0-2) rate was 42.2% [95% CI 27.6; 58.4], and 90-day mortality rate was 15.1% [95% CI 9.8; 22.6]. Postintervention hemorrhage occurred at a rate of 28.6% [CI 17.2; 43.6].

CONCLUSION

Our systematic review and meta-analysis describes the efficacy of the pRESET stent retriever system in managing acute ischemic stroke patients. The pRESET device was found to have a similar safety and efficacy profile to other mechanical thrombectomy devices currently in use.

Association of Admission Hyperglycemia with Clinical Outcomes in Patients with Symptomatic Intracranial Hemorrhage After Endovascular Treatment for Large Vessel Occlusive Stroke

Background

Symptomatic intracranial hemorrhage (sICH) is a fatal complication after endovascular treatment (EVT) for acute large vessel occlusive (LVO) stroke. The aim of this study was to investigate the association between hyperglycemia and outcomes in patients with postprocedural sICH.

Methods

Of the 2567 patients with AIS who underwent EVT from two large multicenter randomized trials and two prospective multicenter registry studies, 324 patients occurred sICH with documented admission glucose were included in this study. The primary outcome was functional independence (defined as a modified Rankin Scale score of 0 to 2) at 90 days. Secondary outcomes included mRS score of 0 to 3, 0 to 1, and mRS score at 90 days. Safety outcome was the mortality within 90 days. Admission hyperglycemia was defined as a plasma blood glucose ≥7.8 mmol/L (140 mg/dL) in our analysis.

Results

Of 324 eligible participants included in this study, hyperglycemia was observed in 130 (40.1%) patients. The median age was 67 (IQR, 58-75) years, and median blood glucose level was 7.1 (IQR, 6.0-9.3) mmol/L. After adjusting for confounding variables, admission hyperglycemia was associated with decreased odds of functional independence (adjusted odds ratio[OR] 0.34; 95% CI 0.17-0.68; P= 0.003), decreased odds of favorable outcome (adjusted OR 0.31; 95% CI 0.16-0.58; P < 0.001) and increased odds of mortality (adjusted OR 2.56; 95% CI 1.47-4.45; P = 0.001) at 90 days. After 1:1 propensity score matching analysis, the results were consistent with multivariable logistic regression analysis.

Conclusion

In patients who suffered sICH after EVT for acute large vessel occlusive stroke, hyperglycemia is a strong predictor of poor clinical outcome and mortality at 90 days.

Improved technical outcomes with converting thrombectomy techniques after failed first pass recanalization

BACKGROUND

A higher number of recanalization attempts reduces the efficacy of endovascular thrombectomy (EVT) for acute ischemic stroke secondary to large vessel occlusion (LVO). We assessed the impact of switching EVT techniques after a failed first pass on procedural and clinical outcomes.

METHODS

This multicenter international study, conducted between January 2013 and December 2022, included patients undergoing EVT for anterior circulation LVO (internal carotid artery or M1 segments) with failed first pass recanalization. Propensity score matching identified a 1:1 matched cohort of patients in whom EVT technique was changed after a failed first pass and those with the same technique repeated. The primary outcome was successful recanalization at second attempt defined as Thrombolysis in Cerebral Ischemia (TICI) score of 2B or higher. Secondary outcomes were 90-day modified Rankin Score (mRS) and postprocedural hemorrhage.

RESULTS

Among 2167 patients, converting to an alternative technique after a failed first pass was associated with higher odds of successful recanalization (adjusted OR (aOR)=1.5, p=0.041), and higher odds of mRS 0-2 at 90 days (aOR=1.6, p=0.005) without additional risk of symptomatic hemorrhage (p=0.379). Using a propensity score matched cohort of 490 patients, technique conversion at second attempt increased odds of successful recanalization at second attempt (aOR=1.32, p=0.006) and 90-day mRS 0-2 (aOR=1.38, p=0.008).

CONCLUSIONS

Early conversion to an alternative EVT technique after a failed first pass recanalization in patients with AIS is associated with better technical success and clinical outcomes.

Multi-Target and Multi-Phase Adjunctive Cerebral Protection for Acute Ischemic Stroke in the Reperfusion Era

Stroke remains the leading cause of death and disability in some countries, predominantly attributed to acute ischemic stroke (AIS). While intravenous thrombolysis and endovascular thrombectomy are widely acknowledged as effective treatments for AIS, boasting a high recanalization rate, there is a significant discrepancy between the success of revascularization and the mediocre clinical outcomes observed among patients with AIS. It is now increasingly understood that the implementation of effective cerebral protection strategies, serving as adjunctive treatments to reperfusion, can potentially improve the outcomes of AIS patients following recanalization therapy. Herein, we reviewed several promising cerebral protective methods that have the potential to slow down infarct growth and protect ischemic penumbra. We dissect the underlying reasons for the mismatch between high recanalization rates and moderate prognosis and introduce a novel concept of "multi-target and multi-phase adjunctive cerebral protection" to guide our search for neuroprotective agents that can be administered alongside recanalization therapy.

Selective intra-arterial hypothermia combined with endovascular thrombectomy for large vessel occlusion: A systematic review and meta-analysis

BACKGROUND

Systemic therapeutic hypothermia may improve outcomes after acute ischemic stroke but increases complications. Selective intra-arterial hypothermia at the ischemic site during endovascular thrombectomy (EVT) theoretically offers benefits with fewer risks. However, there is little clinical evidence to support this approach.

METHODS

We searched Medline/PubMed, Embase and Cochrane electronic databases for studies evaluating the safety and feasibility of selective intra-arterial hypothermia as an adjunct to EVT for large vessel occlusion (LVO). Effect sizes with 95% confidence intervals (CIs) were pooled using the fixed-effect model. Odds ratios (ORs) were computed for binary variables, while the mean differences (MDs) were pooled for continuous data.

RESULTS

Of identified records, five clinical studies involving 463 LVO patients (62.9% male) were included. Of those, 224 (48.4%) patients received adjuvant selective intra-arterial hypothermia, while 239 (51.6%) received EVT alone. Selective intra-arterial hypothermia resulted in higher rates of good functional outcome (modified Rankin scale [mRS] 0-2 at 90-days) (OR 2.07, [95% CI, 1.36 to 3.16]), and lower final infarct volume (MD, -20.96 ml [95% CI, -26.17 to -15.75]) and lower rates of severe disability (mRS 3-5 at 90 days) (OR 0.44 [95% CI, 0.26 to 0.75]). Safety parameters including rates of symptomatic intracerebral hemorrhage, mortality, pneumonia, coagulation abnormalities, and arterial spasm were comparable between groups.

CONCLUSIONS

The initial evidence supports the safety and feasibility of selective intra-arterial hypothermia when combined with EVT for LVO. This approach shows promise for advancing research on neuroprotective strategies for ischemic stroke.

Derivation and validation of a predictive scale to expedite endovascular intervention for acute stroke patients with an intervenable vessel occlusion

BACKGROUND

Early endovascular intervention team mobilization may reduce reperfusion times and improve clinical outcomes for patients with acute ischemic stroke (AIS) with a possible intervenable vessel occlusion (IVO). In an emergency department or mobile stroke unit, incorporating rapidly available non-contrast CT (NCCT) information with examination findings may improve the accuracy of arterial occlusion prediction scales. For this purpose, we developed a rapid and straightforward IVO predictive instrument-the T3AM2PA1 scale.

METHODS

The T3AM2PA1 scale was retrospectively derived from our 'Get with the Guidelines' database. We included all patients with acute stroke alert between January 2017 and August 2018 with a National Institutes of Health Stroke Scale (NIHSS) score between 5 and 25 inclusive. Different pre-intervention variables were collected, including itemized NIHSS and NCCT information. The T3AM2PA1 scale was also compared with other commonly used scales and was validated in a separate sequential retrospective cohort of patients with a full range of NIHSS scores.

RESULTS

574 eligible patients from 2115 acute stroke alerts were identified. The scale was established with five items (CT hyperdense sign, parenchymal hypodensity, lateralizing hemiparesis, gaze deviation, and language disturbance), with a total score of 9. To minimize unnecessary angiography, a cut-off of ≥5 for IVO detection yielded a sensitivity of 52%, a specificity of 90%, and a positive predictive value of 76%.

CONCLUSIONS

The T3AM2PA1 scale accurately predicts the presence of clinical IVO in patients with AIS. Adopting the T3AM2PA1 scale could reduce revascularization times, improve treatment outcomes, and potentially reduce disability.

Trial selection criteria should not be used for clinical decisions and recommendations: the thrombectomy trials example

BACKGROUND

Despite multiple calls for more inclusive studies, most clinical trial eligibility criteria remain too restrictive. Thrombectomy trials have been no exception.

METHODS

We review the landmark trials that have shown the benefits of thrombectomy, their eligibility criteria, and consequences on clinical practice. We discuss the rationale behind various reasons for exclusions. We also examine the logical problem involved in using eligibility criteria as indications for treatment.

RESULTS

Most thrombectomy trials have been too restrictive. This has been shown by a plethora of follow-up studies that have refuted most of the previously recommended trial eligibility restrictions. Meanwhile, the effect of clinical recommendations based on restrictive eligibility criteria is that treatment has been denied to the majority of patients who could have benefitted. Trial eligibility criteria cannot be used to make clinical decisions or recommendations unless, like any other medical diagnosis, they have been shown capable of reliably differentiating patients into those that will, and those that will not benefit from treatment. This goal can only be achieved with all-inclusive pragmatic trials.

CONCLUSION

Restrictive eligibility criteria render clinical trials incapable of guiding medical decisions or recommendations.

Vertebrobasilar Artery Occlusion Treatment Outcomes Within 24 hours of Estimated Occlusion Time

BACKGROUND AND OBJECTIVES

The aim of this study was to investigate the efficacy and safety of endovascular treatment (EVT) in patients with acute vertebrobasilar artery occlusion (VBAO) within 24 hours of estimated occlusion time (EOT) and to evaluate the effect of early and late time window in a cohort of patients with VBAO treated with EVT.

METHODS

Retrospective analysis was conducted on patients within 24 hours of the EOT in 65 stroke centers in China. Favorable outcome was defined as modified Rankin Scale ≤3 at 90 days. Patients were divided into the medical management (MM) group and the EVT group. Times were dichotomized into early (EOT ≤6 hours) and late (>6 hours) time windows. Multivariate logical regression models were used to evaluate the efficacy and safety of EVT and the effect of time windows on outcomes in EVT patients.

RESULTS

Among 4124 patients, 2473 and 1651 patients were included in the early and late windows, respectively. 1702 patients received MM and 2422 were treated with EVT. EVT was associated with a higher rate of a favorable outcome at 90 days both in early (odds ratio [OR] 2.16, 95% CI 1.94-2.41) and late (OR 1.89, 95% CI 1.65-2.17) time windows. No differences were found regarding favorable outcome (OR 0.95, 95% CI 0.87-1.03) between VBAO patients treated with EVT within and beyond 6 hours.

CONCLUSION

Patients with acute VBAO who received EVT within 24 hours were associated with improved favorable outcome compared with patients who received MM. EVT beyond 6 hours is feasible and safe with no increase in symptomatic intracranial hemorrhage.

Iatrogenic arterial vasospasm during mechanical thrombectomy requiring treatment with intra-arterial nimodipine might be associated with worse outcomes

BACKGROUND AND PURPOSE

Vasospasm is a common iatrogenic event during mechanical thrombectomy (MT). In such circumstances, intra-arterial nimodipine administration is occasionally considered. However, its use in the treatment of iatrogenic vasospasm during MT has been poorly studied. We investigated the impact of iatrogenic vasospasm treated with intra-arterial nimodipine on outcomes after MT for large vessel occlusion stroke.

METHODS

We conducted a retrospective analysis of the multicenter observational registry Endovascular Treatment in Ischemic Stroke (ETIS). Consecutive patients treated with MT between January 2015 and December 2022 were included. Patients treated with medical treatment alone, without MT, were excluded. We also excluded patients who received another in situ vasodilator molecule during the procedure. Outcomes were compared according to the occurrence of cervical and/or intracranial arterial vasospasm requiring intraoperative use of in situ nimodipine based on operator's decision, using a propensity score approach. The primary outcome was a modified Rankin Scale (mRS) score of 0-2 at 90 days. Secondary outcomes included excellent outcome (mRS score 0-1), final recanalization, mortality, intracranial hemorrhage and procedural complications. Secondary analyses were performed according to the vasospasm location (intracranial or cervical).

RESULTS

Among 13,678 patients in the registry during the study period, 434 received intra-arterial nimodipine for the treatment of MT-related vasospasm. In the main analysis, comparable odds of favorable outcome were observed, whereas excellent outcome was significantly less frequent in the group with vasospasm requiring nimodipine (adjusted odds ratio [aOR] 0.78, 95% confidence interval [CI] 0.63-0.97). Perfect recanalization, defined as a final modified Thrombolysis In Cerebral Infarction score of 3 (aOR 0.63, 95% CI 0.42-0.93), was also rarer in the vasospasm group. Intracranial vasospasm treated with nimodipine was significantly associated with worse clinical outcome (aOR 0.64, 95% CI 0.45-0.92), in contrast to the cervical location (aOR 1.37, 95% CI 0.54-3.08).

CONCLUSION

Arterial vasospasm occurring during the MT procedure and requiring intra-arterial nimodipine administration was associated with worse outcomes, especially in case of intracranial vasospasm. Although this study cannot formally differentiate whether the negative consequences were due to the vasospasm itself, or nimodipine administration or both, there might be an important signal toward a substantial clinical impact of iatrogenic vasospasm during MT.

Effect of MR-guided perfusion imaging mismatch profiles within 6 h on endovascular thrombectomy outcomes

BACKGROUND

The treatment of acute ischemic stroke (AIS) aims to achieve early vascular recanalization and reperfusion of the penumbra. However, the effect of early penumbral imaging within 6 h on clinical outcomes remains unclear. The objective of this study was to determine the effect of magnetic resonance-guided (MR-guided) perfusion imaging within 6 h after symptom onset on endovascular thrombectomy outcomes in AIS patients.

METHODS

We prospectively collected the clinical information of consecutive AIS patients undergoing endovascular thrombectomy based on MR-guided perfusion imaging within 6 h after symptom onset from AISRNA and EVTRNA studies. The primary outcome was defined as the poor outcome (mRS > 2 within 90 days). The perfusion-weighted imaging/diffusion-weighted imaging (PWI/DWI) mismatch was assessed by an automated software.

RESULTS

We enrolled 84 patients (25 in the mismatch ≤ 1.8 group and 59 in the mismatch > 1.8 group). Significant difference was found between the mismatch > 1.8 group and the mismatch ≤ 1.8 group for the incidence of disabling stroke (mRS > 2) within 90 days (40.7% vs. 68.0%, OR: 3.099, 95% CI: 1.154-8.323, P = 0.025). Intracranial hemorrhage occurred in 8 patients (13.6%) in the mismatch > 1.8 group and 10 patients in the mismatch ≤ 1.8 group (40.0%) (P = 0.010). The risk of severe cerebral edema was 2/59 (3.4%) vs. 7/25 (28.0%) (P = 0.004). These findings remained stable after adjustment.

CONCLUSIONS

MR-guided perfusion imaging mismatch profiles within 6 h after symptom onset may be feasible to predictclinical outcomes and reduce clinically ineffective reperfusion after endovascular thrombectomy.