Mechanical Thrombectomy in Basilar Artery Occlusion

Successful mechanical thrombectomy with an aspiration catheter for fenestrated basilar artery occlusion guided by preoperative basi-parallel anatomical scanning

Basilar artery (BA) fenestration and its occlusion are relatively rare conditions. Mechanical thrombectomy for fenestrated BA occlusion has a high risk of complications. One limb occlusion or partial occlusion of fenestration mimics arterial stenosis or dissection. We present the case of a 75-year-old woman who presented with slight dysarthria, which subsequently worsened. Magnetic resonance imaging, magnetic resonance angiography, and basi-parallel anatomical scanning (BPAS) revealed BA fenestration and occlusion of the larger limb of the fenestrated BA, for which we performed thrombectomy with aspiration and achieved Thrombolysis in Cerebral Infarction Grade 3 flow restoration without procedure-related complications. If BA occlusion occurs at a site where a thrombus does not normally occur, confirming the anatomy of the BA before thrombectomy is desirable. As we obtained information on BA fenestration and occluded limb diameter using preoperative BPAS, we were able to safely achieve effective recanalization by guiding a relatively large-diameter aspiration catheter to the thrombus coaxially with a micro-guidewire and microcatheter.

Basilar artery occlusion location and clinical outcome: data from the ATTENTION multicenter registry

BACKGROUND

Acute basilar artery occlusion is a disabling and life-threatening condition. The purpose of this study was to evaluate the impact of occluded vessel location on the prognostic outcomes of patients who underwent endovascular treatment for acute basilar artery occlusion.

METHODS

Patient data for this study were obtained from the ATTENTION registry. Baseline data of the patients were described and compared across different occlusion locations. Univariable and multivariable regression analyses were performed to assess the effect of occluded vessel location on associated prognostic outcomes.

RESULTS

A total of 1672 patients were included in the analysis, with 583 having distal occlusion, 540 having middle occlusion, and 549 having proximal occlusion. Unlike distal occlusion, both proximal and middle occlusions were significantly and negatively associated with favorable clinical outcomes (for modified Rankin Scale score 0-3: adjusted odds ratio (aOR) 0.634, 95% confidence interval (95% CI) 0.493 to 0.816, P<0.001 in middle occlusion, and aOR 0.620, 95% CI 0.479 to 0.802, P<0.001 in proximal occlusion). Mortality was higher in patients with proximal and middle occlusions (aOR 1.461, 95% CI 1.123 to 1.902, P=0.005 in middle occlusion, and aOR 1.648, 95% CI 1.265 to 2.147, P<0.001 in proximal occlusion). The occluded vessel location was not associated with symptomatic intracranial hemorrhage.

CONCLUSIONS

Proximal and middle basilar artery occlusions were predominantly associated with poor clinical outcomes and increased risk of death following endovascular treatment.

Predictors of outcome and symptomatic intracranial hemorrhage in acute basilar artery occlusions: Analysis of the PC-SEARCH thrombectomy registry

INTRODUCTION

Recent randomized controlled trials demonstrated superiority of mechanical thrombectomy compared to medical therapy in acute basilar artery occlusions, however, little data is available to guide clinicians in functional prognosis and risk stratification.

PATIENTS AND METHODS

Data from the retrospectively established PC-SEARCH Thrombectomy registry, which included patients with basilar artery occlusion from eight sites from January 2015 to December 2021, was interrogated. Outcomes were dichotomized into 90-day favorable (mRS ⩽ 3) and unfavorable (mRS > 3). Multivariate logistic regression analysis was performed with respect to the outcome groups and were adjusted for potential confounding baseline characteristics.

RESULTS

Four-hundred-forty-four patients were included in this analysis. Mean age was 66 [SD 15], with 56% male, and comprised of 76% Caucasian. Patients presented with an initial median NIHSS of 18 and 199 patients (44.8%) achieved favorable 90-day functional outcomes. Independent predictors of favorable outcomes included younger age, pc-ASPECTS > 8 (OR 2.30 p < 0.001), and TICI ⩾ 2b (OR 7.56 p < 0.001). Unfavorable outcomes were associated with increasing number of passes (OR 1.29 p = 0.004) and sICH (OR 4.19 p = 0.015). IA-tPA was an independent risk factor for sICH (OR 7.15 p = 0.002) without improving favorable functional outcomes.

CONCLUSION AND DISCUSSION

PC-ASPECTS > 8, successful recanalization (TICI ⩾ 2b), first-pass recanalization, and younger age are independent predictors of favorable 90-day functional outcome in thrombectomy treated patients with acute basilar artery occlusion. Conversely, sICH were independent predictors of unfavorable outcomes. IA-tPA and unsuccessful recanalization are independently associated with sICH.

Effect of Stroke Etiology on Endovascular Treatment for Acute Basilar-Artery Occlusion: A Post Hoc Analysis of the ATTENTION Randomized Trial

BACKGROUND

Stroke etiology could influence the outcomes in patients with basilar-artery occlusion (BAO). This study aimed to evaluate the differences in efficacy and safety of best medical treatment (BMT) plus endovascular treatment (EVT) versus BMT alone in acute BAO across different stroke etiologies.

METHODS

The study was a post hoc analysis of the ATTENTION trial (Trial of Endovascular Treatment of Acute Basilar-Artery Occlusion), which was a multicenter, randomized trial at 36 centers in China from February 2021 to September 2022. Patients with acute BAO were classified into 3 groups according to stroke etiology (large-artery atherosclerosis [LAA], cardioembolism, and undetermined cause/other determined cause [UC/ODC]). The primary outcome was a favorable outcome (modified Rankin Scale score of 0-3) at 90 days. Safety outcomes included symptomatic intracranial hemorrhage and 90-day mortality.

RESULTS

A total of 340 patients with BAO were included, 150 (44.1%) had LAA, 72 (21.2%) had cardioembolism, and 118 (34.7%) had UC/ODC. For patients treated with BMT plus EVT and BMT alone, respectively, the rate of favorable outcome at 90 days was 49.1% and 23.8% in the LAA group (odds ratio, 3.08 [95% CI, 1.38-6.89]); 52.2% and 30.8% in the cardioembolism group (odds ratio, 2.45 [95% CI, 0.89-6.77]); and 37.5% and 17.4% in the UC/ODC group (odds ratio, 2.85 [95% CI, 1.16-7.01]), with P=0.89 for the stroke etiology×treatment interaction. The rate of symptomatic intracranial hemorrhage in EVT-treated patients with LAA, cardioembolism, and UC/ODC was 8.3%, 2.2%, and 3.2%, respectively, and none of the BMT-treated patients. Lower 90-day mortality was observed in patients with EVT compared with BMT alone across 3 etiology groups.

CONCLUSIONS

Among patients with acute BAO, EVT compared with BMT alone might be associated with favorable outcomes and lower 90-day mortality, regardless of cardioembolism, LAA, or UC/ODC etiologies. The influence of stroke etiology on the benefit of EVT should be explored by further trials.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT04751708.

Posterior circulation collaterals as predictors of outcome in basilar artery occlusion: a sub-analysis of the BASICS randomized trial

Introduction and purpose

Basilar artery occlusion (BAO) is still one of the most devastating neurological conditions associated with high morbidity and mortality. In the present study, we aimed to assess the role of posterior circulation collaterals as predictors of outcome in the BASICS trial and to compare two grading systems (BATMAN score and PC-CS) in terms of prognostic value.

Methods

We performed a sub-analysis of the BASICS trial. Baseline clinical and imaging variables were analyzed. For the imaging analysis, baseline CT and CTA were analyzed by a central core lab. Only those patients with good or moderate quality of baseline CTA and with confirmed BAO were included. Multivariable binary logistic regression analysis was used to test the independent association of clinical and imaging characteristics with a favorable outcome at 3 months (defined as a modified Rankin Score of ≤3). ROC curve analysis was used to assess and compare accuracy between the two collateral grading systems.

Results

The mean age was 67.0 (±12.5) years, 196 (65.3%) patients were males and the median NIHSS was 21.5 (IQR 11-35). Median NCCT pc-ASPECTS was 10 (IQR10-10) and median collateral scores for BATMAN and PC-CS were 8 (IQR 7-9) and 7 (IQR 6-8) respectively. Collateral scores were associated with favorable outcome at 3 months for both BATMAN and PC-CS but only with a modest accuracy on ROC curve analysis (AUC 0.62, 95% CI [0.55-0.69] and 0.67, 95% CI [0.60-0.74] respectively). Age (OR 0.97, 95% CI [0.95-1.00]), NIHSS (OR 0.91, 95% CI [0.89-0.94]) and collateral score (PC-CS - OR 1.2495% CI [1.02-1.51]) were independently associated with clinical outcome.

Conclusion

The two collateral grading systems presented modest prognostic accuracy. Only the PC-CS was independently associated with a favorable outcome at 3 months.

Technical Risk Stratification Nomogram Model for 90-Day Mortality Prediction in Patients With Acute Basilar Artery Occlusion Undergoing Endovascular Thrombectomy: A Multicenter Cohort Study

BACKGROUND

This study aimed to establish and validate a nomogram model for predicting 90-day mortality in patients with acute basilar artery occlusion receiving endovascular thrombectomy.

METHODS AND RESULTS

A total of 242 patients with basilar artery occlusion undergoing endovascular thrombectomy were enrolled in our study, in which 172 patients from 3 stroke centers were assigned to the training cohort, and 70 patients from another center were assigned to the validation cohort. Univariate and multivariate logistic regression analyses were adopted to screen prognostic predictors, and those with significance were subjected to establish a nomogram model in the training cohort. The discriminative accuracy, calibration, and clinical usefulness of the nomogram model was verified in the internal and external cohorts. Six variables, including age, baseline National Institutes of Health Stroke Scale score, Posterior Circulation-Alberta Stroke Program Early CT (Computed Tomography) score, Basilar Artery on Computed Tomography Angiography score, recanalization failure, and symptomatic intracranial hemorrhage, were identified as independent predictors of 90-day mortality of patients with basilar artery occlusion and were subjected to develop a nomogram model. The nomogram model exhibited good discrimination, calibration, and clinical usefulness in both the internal and the external cohorts. Additionally, patients were divided into low-, moderate-, and high-risk groups based on the risk-stratified nomogram model.

CONCLUSIONS

Our study proposed a novel nomogram model that could effectively predict 90-day mortality of patients with basilar artery occlusion after endovascular thrombectomy and stratify patients with high, moderate, or low risk, which has a potential to facilitate prognostic judgment and clinical management of stroke.

Development and validation of a novel scoring system for acute ischemic stroke

BACKGROUND

This study aimed to assess the clinical application of the Artery Occlusion Image Score (AOIS), a new metric based on computed tomographic angiography (CTA) that reflects the severity of occlusive changes in the main intracranial arteries.

MATERIALS AND METHODS

Patients diagnosed with acute ischemic stroke (AIS) were divided into three groups: anterior circulation infarcts (ACI group), posterior circulation infarcts (PCI group), and both anterior and posterior circulation infarcts (ACI + PCI group). The sensitivity and specificity of AOIS were evaluated using the Basilar Artery on Computed Tomography Angiography (BATMAN) score, the Clot Burden Score (CBS), and the National Institutes of Health Stroke Scale (NIHSS) as comparators through receiver-operating characteristic (ROC) curve analysis.

RESULTS

The final analysis included 439 consecutive patients. In the ACI group, AOIS demonstrated high sensitivity (86.3%) and specificity (85.0%) and outperformed CBS in predicting patient prognosis. In the PCI group, AOIS also showed high sensitivity (88.9%) and specificity (90.0%) and outperformed BATMAN in predicting patient prognosis. In the ACI + PCI group, AOIS positively correlated with the NIHSS score (Spearman's ρ = 0.602, P < .001). Additionally, the scoring time of AOIS did not significantly differ from CBS and BATMAN.

CONCLUSION

AOIS is a convenient and reliable method for guiding treatment and predicting outcomes in patients with ACI or/and PCI. Furthermore, AOIS is the first CTA-based scoring system that covers both the anterior and posterior circulation, providing a convenient and reliable evaluation for patients with concurrent acute ischemic stroke in both circulations.

Endovascular therapy of acute vertebrobasilar occlusions: influence of first-line strategy in the Endovascular Treatment in Ischemic Stroke (ETIS) Registry

BACKGROUND

The choice of the first-line technique in vertebrobasilar occlusions (VBOs) remains challenging. We aimed to report outcomes in a large cohort of patients and to compare the efficacy and safety of contact aspiration (CA) and combined technique (CoT) as a first-line endovascular technique in patients with acute VBOs.

METHODS

We retrospectively analyzed clinical and neuroradiological data of patients with VBOs from the prospective, multicenter, observational Endovascular Treatment in Ischemic Stroke (ETIS) Registry in France between January 2015 and August 2023. The primary outcome was the first pass effect (FPE) rate, whereas modified Thrombolysis In Cerebral Infarction (mTICI) 2b-3 and 2c-3, number of passes, need for rescue strategy, modified Rankin Scale (mRS) 0-2, mortality, and symptomatic intracranial hemorrhage (sICH) were secondary outcomes. We performed univariate and multivariate analyses to investigate differences between the two groups.

RESULTS

Among the 583 included patients (mean age 66.2 years, median National Institutes of Health Stroke Scale (NIHSS) 13, median posterior circulation Alberta Stroke Program Early CT Score (pc-ASPECTS) 8), 393 were treated with CA alone and 190 with CoT. Procedures performed with CA were shorter compared with CoT (28 vs 47 min, P<0.0001); however, no differences were observed in terms of FPE (CA 43.3% vs CoT 38.4%, P=0.99), and successful final recanalization (mTICI 2b-3, CA 92.4% vs CoT 91.8%, P=0.74) did not differ between the two groups. Functional independence and sICH rates were also similar, whereas mortality was significantly lower in the CA group (34.5% vs 42.9%; OR 1.79, 95% CI 1.03 to 3.11).

CONCLUSIONS

We observed no differences in FPE, mTICI 2b-3, sICH, and functional independence between the two study groups. First-line CA was associated with shorter procedures and lower mortality rates than CoT.

Endovascular Therapy for Basilar Artery Occlusion in Sudden Onset to Maximal Deficit Ischemic Events

BACKGROUND

The presence of sudden onset to maximal deficit (SOTMD) in patients with acute basilar artery occlusion often results in more severe outcomes. However, the effect of endovascular therapy on SOTMD and whether the outcome is affected by onset-to-puncture time remain unclear.

METHODS AND RESULTS

This retrospective analysis was conducted using data from the prospective BASILAR (Endovascular Treatment for Acute Basilar Artery Occlusion Study Registry). Consecutive patients with basilar artery occlusion receiving endovascular therapy were dichotomized into SOTMD and non-SOTMD cohorts. The primary outcomes included a favorable outcome (modified Rankin scale 0-3), recanalization, and mortality at 90 days. The outcomes of patients with SOTMD were analyzed using multivariable logistic regression. In the multivariate analysis, a favorable outcome was similar between the two cohorts (odds ratio [OR], 0.88 [95% CI, 0.58-1.34]; P=0.5), although the mortality of patients with SOTMD was higher than that of patients with non-SOTMD (OR, 1.67 [95% CI, 1.14-2.44]; P=0.008). The probability of mortality increased from 40.0% at 1 hour to 70.0% at 6 hours in the SOTMD cohort, and favorable outcomes of patients with non-SOTMD declined from 38.0% at 1 hour to 18.0% at 8 hours.

CONCLUSIONS

No significant difference was observed in favorable outcomes between the SOTMD and non-SOTMD groups, although mortality was higher in the SOTMD cohort. The patients with SOTMD had a stronger time dependence for endovascular therapy in terms of mortality, while the time dependency regarding favorable outcome in the NSOTMD group was even higher.

REGISTRATION

URL: https://www.chictr.org.cn; Unique identifier: ChiCTR1800014759.

Development and validation of machine learning-based model for mortality prediction in patients with acute basilar artery occlusion receiving endovascular treatment: multicentric cohort analysis

BACKGROUND

Predicting mortality in stroke patients using information available before endovascular treatment (EVT) is an essential component for supporting clinical decision-making. Although the mortality rate of acute basilar artery occlusion (ABAO) after EVT has reached 40%, few studies have focused on predicting mortality in these individuals. Thus, we aimed to develop and validate a machine learning-based mortality prediction tool based on preoperative information for ABAO patients receiving EVT.

METHODS

The derivation cohort comprised patients from southern provinces of China in the BASILAR registry. The model (POSITIVE: Predicting mOrtality of baSilar artery occlusion patIents Treated wIth EVT) was trained and optimized using a fivefold cross-validation method in which hyperparameters were selected and fine-tuned. This model was retrospectively tested in patients from the northern provinces of China from the BASILAR registry. A prospective test of POSITIVE was performed on consecutive patients from two hospitals between January 2020 and June 2022.

RESULTS

Extreme gradient boosting was employed to construct the POSITIVE model, which achieved the best predictive performance among the eight machine learning algorithms and showed excellent discrimination (area under the curve (AUC) 0.83, 95% confidence interval (95% CI) 0.80 to 0.87) and calibration (Hosmer-Lemeshow test, P>0.05) in the development cohort. AUC yielded by the POSITIVE model for the retrospective test was 0.79 (95% CI 0.71 to 0.85), higher than that obtained by traditional models. Prospective comparisons showed that the POSITIVE model achieved the highest AUC (0.82, 95% CI 0.74 to 0.90) among all prediction models.

CONCLUSION

We developed a machine learning algorithm and retrospective and prospective testing with multicentric cohorts, which exhibited a solid predictive performance and may act as a convenient reference to guide decision-making for ABAO patients. The POSITIVE model is presented online for user-friendly access.

Dynamic and visual nomograms to online predict unfavorable outcome of mechanical thrombectomy for acute basilar artery occlusion

BACKGROUND

The evidence of mechanical thrombectomy (MT) in basilar artery occlusion (BAO) was limited. This study aimed to develop dynamic and visual nomogram models to predict the unfavorable outcome of MT in BAO online.

METHODS

BAO patients treated with MT were screened. Preoperative and postoperative nomogram models were developed based on clinical parameters and imaging features. An independent dataset was collected to perform external validation. Web-based calculators were constructed to provide convenient access.

RESULTS

A total of 127 patients were included in the study, and 117 of them were eventually included in the analysis. The nomogram models showed robust discrimination, with an area under the receiver operating characteristic (ROC) of 0.841 (preoperative) and 0.916 (postoperative). The calibration curves showed good agreement. The preoperative predictors of an unfavorable outcome were previous stroke, the National Institutes of Health Stroke Scale (NIHSS) at admission, and the posterior circulation Alberta Stroke Program Early Computed Tomography Score (pc-ASPECTS). The postoperative predictors were previous stroke, NIHSS at 24 h, and pc-ASPECTS.

CONCLUSION

Dynamic and visual nomograms were constructed and validated for the first time for BAO patients treated with MT, which provided precise predictions for the risk of an unfavorable outcome. The preoperative model may assist clinicians in selecting eligible patients, and the postoperative model may facilitate individualized poststroke management.

Basilar artery bifurcation anatomy as a determinant of recanalization and stroke outcome: Basilar artery bifurcation anatomy and stroke outcome

OBJECTIVES

Thrombectomy improves outcomes in patients with basilar artery (BA) occlusion. We hypothesized that the anatomic configuration of the BA bifurcation, classified as T- or Y-shaped, may impact the outcome as a T-shaped BA would involve more deep penetrating arteries of the midbrain and thalamus.

MATERIALS AND METHODS

In this 2-center retrospective cohort study, we included patients with stroke due to distal BA occlusion and performed blinded classification of their BA distal bifurcation as either T- or Y-shaped. The primary outcomes were favorable outcome at 90-days (modified Rankin Scale 0 - 2) and successful recanalization (TICI scores 2B or 3).

RESULTS

70 patients (mean age 66 years, 36% women) were included. 38 had T- and 32 had Y-shaped bifurcations. Baseline characteristics were similar for both groups, including demographics, onset to arterial puncture time, baseline NIHSS, THRIVE score, posterior circulation collateral score, and presence of tandem occlusion. Comparing the T- to the Y- shape, there was no difference in the likelihood of successful recanalization (RR: 1.02, CI: [0.86-1.21], p=1.00) nor 90-day favorable mRS (0-2) score (RR: 0.58, CI: [0.25-1.32]; p=0.18). Similarly, mortality at 30 and 90-days were not significantly affected by the type of bifurcation.

CONCLUSIONS

The configuration of the basilar artery does not significantly impact on recanalization success or stroke outcome in our study. Further studies are needed to confirm our observations.

Predictors of Angiographic Outcome After Failed Thrombectomy for Large Vessel Occlusion: Insights from the Stroke Thrombectomy and Aneurysm Registry

BACKGROUND

Mechanical thrombectomy failure (MTF) occurs in approximately 15% of cases.

OBJECTIVE

To investigate factors that predict MTF.

METHODS

This was a retrospective review of prospectively collected data from the Stroke Thrombectomy and Aneurysm Registry. Patients who underwent mechanical thrombectomy (MT) for large vessel occlusion (LVO) were included. Patients were categorized by mechanical thrombectomy success (MTS) (≥mTICI 2b) or MTF (

RESULTS

A total of 6780 patients were included, and 1001 experienced anterior circulation MTF. Patients in the MTF group were older (73 vs 72, P = .044) and had higher poor premorbid modified Rankin Scale (mRS) (10.8% vs 8.4%, P = .017). Onset to puncture time was greater in the MTF group (273 vs 260 min, P = .08). No significant differences were found between the access site, use of balloon guide catheter, frontline technique, or first-pass devices between the MTF and MTS groups. More complications occurred in the MTF group (14% vs 5.8%), including symptomatic intracerebral hemorrhage (9.4% vs 6.1%) and craniectomies (10% vs 2.8%) ( P < .001). On UVA, age, poor pretreatment mRS, increased number of passes, and increased procedure time were associated with MTF. Internal carotid artery, M1, and M2 occlusions had decreased odds of MTF. Poor preprocedure mRS, number of passes, and procedure time remained significant on MVA. A subgroup analysis of posterior circulation LVO revealed that number of passes and total procedure time correlated with increased odds of MTF ( P < .001) while rescue stenting was associated with less odds of MTF (odds ratio 0.20, 95% CI 0.06-0.63). Number of passes remained significant on MVA of posterior circulation occlusion subgroup analysis.

CONCLUSION

Anterior circulation MTF is associated with more complications and worse outcomes. No differences were found between techniques or devises used for the first pass during MT. Rescue intracranial stenting may decrease the likelihood of MTF for posterior circulation MT.

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Key Words Collapse

MESH Headings

• Humans
• Stroke/surgery
• Thrombectomy/methods
• Cerebral Hemorrhage
• Retrospective Studies
• Aneurysm
• Registries
• Treatment Outcome
• Brain Ischemia/therapy

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Affiliation(s)

Matthew Webb Department of Neurosurgery, University of Texas Health Science Center San Antonio, San Antonio , Texas , USA
Muhammed Amir Essibayi Medical University of South Carolina, Charleston , South Carolina , USA
Sami Al Kasab Medical University of South Carolina, Charleston , South Carolina , USA
Ilko L Maier University Medical Center Göttingen, Göttingen , Germany
Marios-Nikos Psychogios University Hospital Basel, Basel , Switzerland
Jonathan A Grossberg Emory University, Atlanta , Georgia , USA
Ali Alawieh Emory University, Atlanta , Georgia , USA
Stacey Quintero Wolfe Wake Forest University, Winston-Salem , North Carolina , USA
Adam Arthur University of Tennessee Health Science Center, Memphis , Tennessee , USA
Travis Dumont Bannner University of Arizona Medical Center, Tucson , Arizona , USA
Peter Kan University of Texas Medical Branch, Galveston , Texas , USA
Joon-Tae Kim Chonnam National University Hospital, Gwangju , South Korea
Reade De Leacy Mount Sinai Health System, New York , New York , USA
Joshua Osbun Washington University in St. Louis, St. Louis , Missouri , USA
Ansaar Rai Department of Neuroradiology, School of Medicine, West Virginia University, Morgantown, West Virginia, USA
Pascal Jabbour Department of Neuroradiology, School of Medicine, West Virginia University, Morgantown, West Virginia, USA
Min S Park Thomas Jefferson University Hospital, Philadelphia , Pennsylvania , USA
Roberto Crosa University of Virginia, Charlottesville , Virginia , USA
Michael R Levitt Centro Endovascular Neurológico, Médica Uruguaya, Montevideo , Uruguay
Adam Polifka University of Washington, Seattle , Washington , USA
Shinichi Yoshimura University of Florida, Gainesville , Florida , USA
Charles Matouk Hyogo College of Medicine, Nishinomiya , Japan
Richard W Williamson Yale School of Medicine, New Haven , Connecticut , USA
Isabel Fragata Allegheny General Hospital, Pittsburgh , Pennsylvania , USA
Shakeel A Chowdhry Centro Hospitalar Universitário de Lisboa Central, Lisboa , Portugal
Robert M Starke NorthShore University Health System, Evanston , Illinois , USA
Edgar A Samaniego University of Miami Health System, Miami , Florida , USA
Hugo Cuellar University of Iowa, Iowa City , Iowa , USA
Alejandro Spiotta Medical University of South Carolina, Charleston , South Carolina , USA
Justin Mascitelli Department of Neurosurgery, University of Texas Health Science Center San Antonio, San Antonio , Texas , USA

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Prognostic factors for acute vertebrobasilar artery occlusion-reperfusion: a multicenter retrospective cohort study

BACKGROUND

This study aimed to analyze the long-term prognostic factors in acute vertebrobasilar artery occlusion (VBAO) patients treated with endovascular treatment (EVT).

METHODS

This study was performed using the acute posterior circulation ischemic stroke registry database from 21 stroke centers in 18 cities in China and retrospectively included consecutive patients aged 18 years or older with an acute, symptomatic, radiologically confirmed VBAO who were treated with EVT between December 2015 and December 2018. Favorable clinical outcomes were evaluated by machine-learning methods. A clinical signature was constructed in the training cohort using the least absolute shrinkage and selection operator regression and was validated in the validation cohort.

RESULTS

From 28 potential factors, 7 variables were independent prognostic factors and were included in the model: Modified Thrombolysis in Cerebral Infarction (M) [odds ratio (OR): 2.900; 95% confidence interval [CI]: 1.566-5.370], age (A) (OR, 0.977; 95% CI: 0.961-0.993), National Institutes of Health Stroke Scale (N) (13-27 vs. ≤12: OR, 0.491; 95% CI: 0.275-0.876; ≥28 vs. ≤12: OR, 0.148; 95% CI: 0.076-0.289), atrial fibrillation (A) (OR, 2.383; 95% CI: 1.444-3.933), Glasgow Coma Scale (G) (OR, 2.339; 95% CI: 1.383-3.957), endovascular stent-retriever thrombectomy (E) (stent-retriever vs. aspiration: OR, 0.375; 95% CI: 0.156-0.902), and estimated time of onset of the occlusion to groin puncture (Time) (OR, 0.950; 95% CI: 0.909-0.993) (abbreviated as MANAGE Time). In the internal validation set, this model was well calibrated with good discrimination [C-index (95% CI)=0.790 (0.755-0.826)]. A calculator based on the model can be found online ( http://ody-wong.shinyapps.io/1yearFCO/ ).

CONCLUSION

Our results indicate that optimizing for EVT, along with specific risk stratification, may improve long-term prognosis. However, a larger prospective study is needed to confirm the findings.

Imaging predictors of clinical outcomes after endovascular treatment in MRI-selected patients with acute basilar artery occlusion

PURPOSE

We aimed to investigate the impact of baseline infarct area and collateral status (CS), which are imaging predictors of clinical outcome following stroke, after endovascular treatment (EVT) in MRI-selected patients with acute basilar artery occlusion (BAO).

METHODS

Patients with acute BAO who underwent EVT within 24 h after stroke from December 2013 to February 2021 were included in this retrospective, multicenter, observational study. The baseline infarct area was evaluated by the posterior circulation of Acute Stroke Prognosis Early Computed Tomography Score (pc-ASPECTS) using diffuse-weighted imaging (DWI), and CS was assessed by measuring the computed tomography angiography of the basilar artery (BATMAN) score and the posterior circulation collateral score (PC-CS) using magnetic resonance angiography (MRA). A Good outcome was defined as a modified Rankin scale score ≤ 3 at 3 months. For each imaging predictor, a multivariate logistic regression analysis was performed to evaluate its impact on good outcomes.

RESULTS

A total of 86 patients were analyzed, and 37 (43.0%) had a good outcome. The latter showed significantly higher pc-ASPECTS than those without good outcomes. In multivariate analyses, a pc-ASPECTS ≥ 7 was significantly associated with good outcomes (OR, 2.98 [95% CI, 1.10-8.13], P = 0.032), while PC-CS ≥ 4 (OR, 2.49 [95% CI, 0.92-6.74], P = 0.073) and BATMAN score ≥ 5 (OR, 1.51 [95% CI, 0.58-3.98], P = 0.401) were not.

CONCLUSIONS

In MRI-selected patients with acute BAO, pc-ASPECTS on DWI was an independent predictor of clinical outcomes after EVT, while the MRA-based CS assessments were not.

What Is the Evidence for Endovascular Thrombectomy in Posterior Circulation Stroke?

Posterior circulation infarcts comprise approximately 25% of ischemic strokes but are less often treated with recanalization therapy and have longer treatment delays compared with anterior circulation strokes. Among posterior circulation strokes, basilar artery occlusion is associated with the most severe deficits and the worst prognosis. Endovascular thrombectomy is a standard of care for patients with anterior circulation large vessel occlusion, but not until recently were the first randomized controlled trials on endovascular thrombectomy in basilar artery occlusion published. Two of the trials were neutral, whereas two others showed better functional outcome after thrombectomy up to 24 hours of symptom onset compared with best medical treatment, which in most cases had low rates of intravenous thrombolysis. According to observational data, thrombectomy seems to be safe also in isolated posterior cerebral artery occlusions and might be an option for selected patients, even if its outcome benefit is yet to be demonstrated.

Mechanical Thrombectomy for Basilar Artery Occlusion with a Type 1 Persistent Proatlantal Artery: A Case Report and Literature Review

Objective

Persistent proatlantal artery (PPA) is a primitive carotid-vertebrobasilar anastomosis (CVA); acute ischemic stroke due to basilar artery (BA) occlusion via a PPA is extremely rare.

Case Presentation

An 84-year-old female developed disturbance of consciousness (Glasgow Coma Scale E2V1M5) and quadriparesis with a National Institutes of Health Stroke Scale score of 35. Head CT revealed early ischemic changes in the right temporal lobe, and a hyperdense vessel sign in the BA. Cerebral angiography showed that the left vertebral artery (VA) did not originate from the left subclavian artery or aortic arch. A left common carotid artery angiogram showed the presence of the left PPA originating from the left external carotid artery. Mechanical thrombectomy (MT) with contact aspiration using a Penumbra 5MAX ACE 60 aspiration catheter was performed, and successful recanalization was achieved after clot retrieval in the first attempt (thrombolysis in cerebral infarction scale 2b). MRI performed the following day, however, revealed a newly developed large hemorrhagic infarction in the pons, with no improvement in her symptoms (modified Rankin Scale score of 5 at 90 days).

Conclusion

Although MT achieved successful recanalization of the BA via the PPA, her clinical symptoms did not improve, probably because of poor collateral circulation or the long length of the occlusion. In patients with acute vertebro-BA occlusion, if the VA does not originate from the subclavian artery or aortic arch, the presence of a primitive CVA should be considered.

Mechanical Thrombectomy for Stroke Due to Acute Basilar Artery Occlusion, a Safety and Efficacy Analysis

BACKGROUND

Acute basilar artery occlusion accounts for 1% of all ischemic strokes but often leads to devastating neurological injury and mortality. Many institutions still opt for best medical therapy for these patients; however, there is increasing evidence that mechanical thrombectomy (MT) for these patients leads to better outcomes.

OBJECTIVE

To assess the safety and efficacy of MT for patients presenting with acute basilar artery occlusion (BAO).

METHODS

This study was a retrospective chart review of a prospectively maintained database for patients with acute BAO treated with MT from January 2014 through March 2022.

RESULTS

Our study included a total of 74 patients. The mean age was 62.7 years, and 55.4% were male. The most common comorbidity was hypertension (73%). The mean door to puncture time was 75 minutes, and the mean procedure time was 54 minutes. 86.5% of patients had a good modified treatment in cerebral ischemia score (≥2b). There were 4 patients who had procedural complications and 3 who had symptomatic intracerebral hemorrhage. At 90 days, 62.5% of patients had a modified Rankin Scale, 0 to 3. The mortality rate was 32.4% and 2% during hospital admission and 90 days, respectively. On univariate analysis, adjunctive angioplasty/stenting and higher presenting National Institutes of Health Stroke Scale score were associated with modified Rankin Scale 4 to 6 at 90 days ( P -value, .03 and <.001, respectively). Shorter procedure time was associated with modified treatment in cerebral ischemia score ≥ 2b ( P -value, .0015).

CONCLUSION

Our findings showed that MT is safe and effective for patients presenting with acute BAO and is in conjunction with previous literature. The results from upcoming trials should hopefully establish MT as gold standard for these patients.

Time-Dependent Endovascular Treatment Effect According to Collateral Status in Basilar Artery Occlusion

Prior studies on anterior circulation stroke have demonstrated that the benefits of endovascular treatment (EVT) may be absent in patients with poor collaterals. Our study focused on patients with basilar artery occlusion (BAO) to investigate time-dependent EVT effects according to the posterior circulation collateral score (PC-CS). The BASILAR study was a nationwide prospective Chinese registry of consecutive BAO patients. Patients were divided into groups receiving standard medical therapy alone (SMT group) or SMT plus EVT (EVT group). Restricted cubic spline analyses (RCSA) were performed to explore the nonlinear and linear relationships between EVT time and outcomes for different PC-CS. We included 828 patients with acute BAO. Compared with the poor collateral (PC-CS 0-3), the adjusted odds ratio of favorable outcome was 1.311 in patients with moderate (PC-CS 4-5) (95% CI, 0.781-2.201) and 1.899 with good (PC-CS 6-10) collateral (1.125-3.207) for EVT. RCSA revealed that in patients with PC-CS 0-3, the favorable outcome probability after EVT significantly decreased to 10% within 6 h and stabilized thereafter (Pnonlinearity = 0.035), while in patients with moderate and good collateral, the probability was maintained at approximately 30% and 40% respectively, even beyond 6 h (all Pnonlinearity > 0.05). Among patients with BAO, good collateral circulation was independently associated with improved outcomes along with the usage of thrombectomy. Patients with poor collaterals should receive EVT as early as possible, especially within 6 h of symptom onset, while the time window may be extended in patients with moderate and good collaterals. Unique identifier: ChiCTR1800014759.

Comparison between collateral status and DEFUSE 3 or DAWN criteria in patient selection for endovascular thrombectomy within 6-24 hours after stroke: a protocol for meta-analysis

INTRODUCTION

Perfusion imaging according to the DEFUSE 3 or DAWN criteria has been applied to select patients with large vascular occlusive stroke undergo endovascular therapy (EVT) in the extended time window. Emerging studies have shown that collateral blood flow-based criteria may be as effective as DEFUSE 3 and DAWN criteria for the evaluation of EVT eligibility beyond 6 hours. We will conduct a meta-analysis to compare collateral status-based criteria with DEFUSE 3 or DAWN criteria.

METHODS AND ANALYSIS

We will conduct a search for the studies comparing collateral blood flow-based imaging with CT perfusion using the DEFUSE 3 or DAWN criteria in selecting patients with acute ischaemic stroke undergo EVT in the Web of Science, PubMed, EMBASE and the Cochrane Library databases between November 2017 and November 2021. We will also search the sources of grey literature, the reference lists of included studies and the newly published studies during the review period. Two investigators will independently screen the eligible studies and extract data. The study quality will be assessed by using the Newcastle-Ottawa Scale or the Cochrane risk bias tool. Stata V.17 will be used to conduct data analysis.

ETHICS AND DISSEMINATION

Patient informed consent and ethics approval are not necessary as this study uses only published studies. The finding of this meta-analysis will be propagated through committee conferences or peer-reviewed journals.

PROSPERO REGISTRATION NUMBER

CRD42021281928.

Effect of vertebrobasilar dolichoectasia on endovascular therapy in acute posterior circulation infarction

Background and purpose

This study aimed to analyze the feasibility and safety of endovascular therapy (EVT) in patients with acute posterior circulation stroke and vertebrobasilar dolichoectasia (VBD).

Materials and methods

BASILAR was a national prospective registry of consecutive patients with symptomatic and imaging-confirmed acute stroke in the posterior circulation within 24 h of symptom onset. We evaluated EVT feasibility and safety in patients with VBD. Primary outcomes included improvement in modified Rankin Scale scores (mRS) at 90 days and mortality within 90 days. The secondary outcome was the rate of favorable functional outcome, defined as mRS ≤ 3 (indicating independent ambulation) at 90 days. Safety outcomes included surgery-related complications and other serious adverse events.

Results

A total of 534 cases were included: 159 with VBD and 375 controls. No significant difference in mRS at 90 days was found between groups, but patients with VBD had a higher baseline National Institutes of Health Stroke Scale (NIHSS) score [30 (19–33) vs. 25 (15–32)] and were older [65 (59–74) vs. 63 (55–72) year]. After propensity score matching, there were no significant differences in baseline NIHSS score between the two groups, and the efficacy and safety of EVT were similar between patients with or without VBD. Furthermore, the prognostic effect of puncture-to-recanalization time on the probability of mortality within 90 days in EVT-treated patients with VBD was significant {adjusted odds ratio, 1.008 [95% confidence interval (1.001–1.015)]}.

Conclusion

Endovascular therapy is safe and feasible in patients with acute posterior circulation stroke and VBD. The puncture-to-recanalization time is important for predicting the prognosis of EVT-treated patients with VBD.

Evaluation of collateral status and outcome in patients with middle cerebral artery stenosis in late time window by CT perfusion imaging

Objectives

Collateral status (CS) is a crucial determinant of outcome in patients with ischemic stroke. We aimed to test whether the cerebral blood volume (CBV) and cerebral blood flow (CBF) based on computed tomography perfusion (CTP) measurements can quantitatively evaluate CS and explore the predictive ability of CTP parameters in determining clinical outcomes in patients with MCA severe stenosis or occlusion presenting beyond 24 h.

Materials and methods

In this retrospective study, data obtained from September 2018 to March 2022 in consecutive stroke patients caused by isolated middle cerebral artery severe stenosis or occlusion were reviewed within 24–72 h after onset. Correlation between the collateral score systems assessed with CT angiography (CTA) and CTP parameters was calculated using the Spearman correlation. The optimal threshold of the CBV ratio for predicting a good outcome was determined using receiver operating characteristic curve (ROC) analysis.

Results

A total of 69 patients met inclusion criteria. Both the CBV ratio and the CBF ratio had significant correlation with collateral score systems assessed with CTA [CBV ratio and Tan score: rs = 0.702, P &lt; 0.0001; CBV ratio and regional leptomeningeal collateral (rLMC) score: rs = 0.705, P &lt; 0.0001; CBV ratio and Miteff score: rs = 0.625, P &lt; 0.0001. CBF ratio and Tan score: rs= 0.671, P &lt; 0.0001; CBF ratio and rLMC score: rs = 0.715, P &lt; 0.0001; CBF ratio and Miteff score: rs = 0.535, P &lt; 0.0001]. ROC analysis revealed the CBV ratio performed better than the qualitative collateral assessments and the CBF ratio in the prediction of a favorable 90-day modified Rankin scale score. The CBV ratio was a useful parameter that predicted a good functional outcome [area under the curve (AUC), 0.922; 95% CI, 0.862 ± 0.982].

Conclusions

In late time window stroke patients, the CBV and CBF ratio on CTP may be valuable parameters for quantitatively revealing the collateral status after stroke. In addition, the CBV ratio was the predictor of clinical outcomes in patients with MCA severe stenosis or occlusion.

Basilar Artery Thrombectomy Between Evidence-Based Medicine and the Real-World Practice: A Single-Center Experience

BACKGROUND AND AIM

Basilar artery occlusion (BAO) is known for its catastrophic outcomes, whether death or disability, in approximately 70% of patients. Mechanical thrombectomy (MT) has been approved as an intervention in large vessel occlusion of anterior circulation, based on multiple randomized controlled trials (RCTs) and meta-analyses. Even though two RCTs appeared recently, there is still uncertainty about the effect of MT in BAO. Our study aims to report the outcome of MT in BAO and the variables affecting good outcomes and mortality rate.

MATERIALS AND METHODS

We retrospectively collected the clinical and radiological data of 30 BAO patients treated in our center by MT between July 2016 and July 2021. A favorable clinical outcome was considered if mRS was ≤2. A favorable radiological result was considered if modified Thrombolysis in Cerebral Infarction (mTICI) was ≥2b at the end of the intervention. Multiple variables were tested for their effects on favorable clinical outcomes and mortality.

RESULTS

The mean age of the 30 patients was 61.23 ± 16.81 years; 20/30 (66.7%) were male. A favorable functional outcome was achieved in 40.7%. Successful revascularization was achieved in 26 patients (86.7%). Mortality at 90 days was observed in 11 patients (36.7%). The presenting National Institute of Health and Stroke Scale (NIHSS) was the only predictor of mortality, and the optimal cut-off value for death was 15 with area under the curve (AUC) = 0.758 (sensitivity 91% and specificity 59%) and P value = 0.02.

CONCLUSION

Thrombectomy is an effective procedure in BAO which has naturally a bad outcome. The presenting NIHSS might be the only predictor of mortality in our study.

Endovascular treatment for distal basilar artery occlusion stroke

Background

This study aimed to investigate the clinical outcomes of endovascular treatment (EVT) for distal basilar artery occlusion (BAO) and compare them with the outcomes of standard medical treatment (SMT) in daily clinical practice.

Methods

Patients with distal BAO enrolled in the BASILAR study from January 2014 to May 2019 were included. Differences in clinical outcomes were analyzed using Pearson's chi-square test and multivariable logistic regression. Clinical outcomes were evaluated using the modified Rankin Scale (mRS) score at 90 days, the mortality at 90 days, and the occurrence of symptomatic intracranial hemorrhage within 48 h.

Results

Among the 267 patients with distal BAO (222 patients in the EVT group and 45 patients in the SMT group), compared with the SMT group, the EVT group was associated with a favorable outcome (mRS 0–3; 40.1 vs. 15.6%; aOR 5.44; 95% CI, 1.68–17.66; P = 0.005) and decreased mortality (44.6 vs. 71.1%, aOR 0.32, 95% CI, 0.13–0.77; P = 0.012). In the EVT group, multivariable analysis showed that the initial National Institutes of Health Stroke Scale (NIHSS) score and posterior circulation-Alberta Stroke Program Early CT Score (pc-ASPECTS) were associated with favorable functional outcomes and mortality.

Conclusion

Our study suggests that, compared with SMT, EVT is technically feasible and safe for patients with distal BAO.

Endovascular Treatment for Posterior Circulation Stroke: Ways to Maximize Therapeutic Efficacy

The efficacy of endovascular treatment (EVT) in patients with posterior circulation stroke has not been proven. Two recent randomized controlled trials failed to show improved functional outcomes after EVT for posterior circulation stroke (PC-EVT). However, promising results for two additional randomized controlled trials have also been presented at a recent conference. Studies have shown that patients undergoing PC-EVT had a higher rate of futile recanalization than those undergoing EVT for anterior circulation stroke. These findings call for further identification of prognostic factors beyond recanalization. The significance of baseline clinical severity, infarct volume, collaterals, time metrics, core-penumbra mismatch, and methods to accurately measure these parameters are discussed. Furthermore, their interplay on EVT outcomes and the potential to individualize patient selection for PC-EVT are reviewed. We also discuss technical considerations for improving the treatment efficacy of PC-EVT.

Case Report: Stent Retriever Thrombectomy of Acute Basilar Artery Occlusion via the Type 1 Proatlantal Intersegmental Artery

Stent retriever thrombectomy (SRT) is one of the most effective methods for the recanalization of acute basilar artery occlusion (ABAO). The proatlantal intersegmental artery (PIA) is a rare carotid-vertebrobasilar anastomosis. Recognition of this rare form of anastomosis is particularly important for the rapid establishment of positive blood flow in patients with ABAO. In this case, the patient had a rare, left type 1 PIA. The right vertebral artery (VA) was tenuous and did not enter the cranium. We performed a thrombectomy of the ABAO by inserting a catheter via the type 1 PIA. The complete recanalization of basilar artery (BA) flow was achieved following two stent retractions; however, the patient eventually died of brain stem hemorrhage.

Tmax profile in computed tomography perfusion-based RAPID software maps influences outcome after mechanical thrombectomy in patients with basilar artery occlusion

BACKGROUND

Computed tomography perfusion (CTP) parameters have been shown to have predictive value for functional outcomes of patients with basilar artery occlusion (BAO). We report the predictive value of CTP-based software (CTP-Rapid Processing of Perfusion and Diffusion (RAPID); iSchemia View) for functional outcomes of patients with BAO after endovascular therapy (EVT).

METHODS

Patients with BAO who underwent EVT were retrospectively analyzed in our center from December 2019 to July 2021. Baseline characteristics and imaging parameters from non-contrast CT, CT angiography (CTA), and CTP-RAPID were collected for analysis.

RESULTS

Among the 55 patients enrolled in this study, 22 (40.0%) achieved a good functional outcome (modified Rankin Scale score ≤3 at 90 days). In the univariate analysis, posterior circulation Alberta Stroke Program Early CT Score, Basilar Artery on CT Angiography score, posterior circulation CTA score, posterior communicating artery deficiency, perfusion deficit volume in time to maximum (Tmax) >4 s, Tmax >6 s, and mismatch volume were associated with functional outcomes (all p<0.05). In the multivariate analysis, perfusion deficit volume in Tmax >6 s (OR 1.011 (95% CI 1.001 to 1.020)) and posterior circulation CTA score (OR 0.435 (95% CI 0.225 to 0.840)) remained independent outcome predictors (all p<0.05).

CONCLUSIONS

Perfusion deficit volume in Tmax >6 s on CTP-RAPID imaging maps and basilar artery on CTA score have potential as functional outcome predictors in patients with BAO after EVT.

Convulsive-like movements as the first symptom of basilar artery occlusive brainstem infarction: A case report

BACKGROUND

Convulsive-like movements are rare in basilar artery occlusive cerebral infarction (BAOCI). These manifestations may easily be mistaken for epileptic seizures caused by compromised anterior circulation or by cortical lesions. Delayed diagnosis of this condition affects its subsequent treatment and prognosis. Therefore, it is critical to recognize this type of phenomenon in the early stage.

CASE SUMMARY

A 55-year-old male patient presented with unconsciousness, rigidity, and a paroxysmal twitch in both lower limbs. These conditions lasted for nearly 2 h and resembled status epilepticus. After the initial conditions subsided, hemiplegia occurred and then subsided rapidly. The family refused thrombolytic therapy because the symptoms were similar to Todd paralysis after epilepsy. However, magnetic resonance imaging showed left pontine infarction. No abnormality was observed in a video electroencephalogram during the interictal period. Digital subtraction angiography revealed that the basilar artery was occluded and that the posterior communicating arteries were patent. Fortunately, the patient received a good prognosis after antiplatelet therapy, lipid regulation, balloon dilatation of the basilar artery, and rehabilitation.

CONCLUSION

Convulsive-like movements may be an early sign of basilar artery occlusive brainstem infarction. It is important to identify this phenomenon in a timely manner.

Thrombectomy in basilar artery occlusions: impact of number of passes and futile reperfusion

BACKGROUND

The number of mechanical thrombectomy (MT) passes is strongly associated with angiographic reperfusion as well as clinical outcomes in patients with anterior circulation ischemic stroke. However, these associations have not been analyzed in patients with basilar artery occlusion (BAO). We investigated the influence of the number of MT passes on the degree of reperfusion and clinical outcomes, and compared outcome after ≤3 passes versus >3 passes.

METHODS

We used data from the prospective multicentric Endovascular Treatment in Ischemic Stroke (ETIS) Registry at 18 sites in France. Patients with BAO treated with MT were included. The primary outcome was a favorable outcome, defined as a modified Rankin Scale score of 0-3 at 90 days. We fit mixed multiple regression models, with center as a random effect.

RESULTS

We included 275 patients. Successful recanalization (modified Thrombolysis In Cerebral Infarction (mTICI) 2b-3) was achieved in 88.4%, and 41.8% had a favorable outcome. The odds ratio for favorable outcome with each pass above 1 was 0.41 (95% CI 0.23 to 0.73) and for recanalization (mTICI 2b-3) it was 0.70 (95% CI 0.57 to 0.87). In patients with ≤3 passes, the rate of favorable outcome in recanalized versus non-recanalized patients was 50.5% versus 10.0% (p=0.001), while in those with >3 passes it was 16.7% versus 15.2% (p=0.901).

CONCLUSIONS

We found that BAO patients had a significant relationship between the number of MT passes and both recanalization and favorable functional outcome. We further found that the benefit of recanalization in BAO patients was significant only when recanalization was achieved within three passes, encouraging at least three passes before stopping the procedure.

Basilar Artery Occlusion (BAO) revascularization after more than 12 hours from the onset of symptoms with excellent outcome: Report of a case

This paper reports a case of basilar artery occlusion (BAO), a relatively rare event associated with high mortality rate and high risk of disability. A 77-year-old man arrived at our Stroke Unit approximately 14 hours after the onset of symptoms (dysarthria and complete left hemiparesis) with progressive worsening up to coma and with a National Institute Health Stroke Scale (NIHSS) of 22.

The patient was treated and, at discharge, the modified Rankin scale and NIHSS were 2 and 5, respectively. The aim of this paper is to illustrate how revascularization treatment, also after 12 hours, could be a viable option to ensure survival and a good life quality for the patient. Furthermore, it is essential to encourage the publication of a greater number of trials about the posterior circulation emphasizing how many favorable prognosis indicators are now recognized.

Posterior Circulation ASPECTS on CT Angiography Predicts Futile Recanalization of Endovascular Thrombectomy for Acute Basilar Artery Occlusion

Background

Acute basilar artery occlusion (BAO) is the most potentially disastrous outcome and has a high risk of recurrence stroke in posterior circulation infarction (PCI). However, the rate of futile recanalization remains high despite successful recanalization. The objective of this study was to investigate 90 days functional outcomes among patients with BAO who underwent endovascular thrombectomy (EVT) and to identify the risk factors associated with futile recanalization.

Methods

We retrospectively analyzed 72 patients with acute BAO who received EVT from January 2018 to June 2021. CT angiography source images posterior circulation Acute Stroke Prognosis Early CT Score (CTA-SI pc-ASPECTS) evaluated the extensive hypoattenuation in patients with BAO. Futile recanalization defined an modified Rankin Scale (mRS) of 3-6 at 90 days despite a successful recanalization. Logistic regression analysis was performed to investigate the predictors of futile recanalization.

Results

Our sample included a total of 55 eligible patients. Patients with poor outcomes showed that the pc-ASPECTS score was lower in patients with poor outcomes than that in patients with good outcomes (P = 0.017). Longer time from symptoms onset-to-the puncture (P = 0.014) and elevation of leucocytes (P = 0.012) were associated with poor outcomes. The multivariable logistic analysis showed that pc-ASPECTS and onset-to-puncture time (OPT) were independent predictors of futile recanalization.

Conclusions

This study suggested that pc-ASPECTS and OPT are independent predictors of futile recanalization after EVT in patients with BAO. The lower pc-ASPECTS score and longer puncture time will have a poor clinical outcome.

Imaging-based outcome prediction in posterior circulation stroke

BACKGROUND AND PURPOSE

We developed a machine learning model to allow early functional outcome prediction for patients presenting with posterior circulation (pc)-stroke based on CT-imaging and clinical data at admission. The proposed algorithm utilizes quantitative information from automated multidimensional assessments of posterior circulation Acute Stroke Prognosis Early CT-Score (pc-ASPECTS) regions. Discriminatory power was compared to predictions based on conventional pc-ASPECTS ratings.

METHODS

We retrospectively analyzed non-contrast CTs and clinical data of 172 pc-stroke patients. 90 days outcome was dichotomized into good and poor using modified Rankin Scale (mRS) cut-offs. Predictive performance was assessed for outcome differentiation at mRS 2, 3, 4 and survival prediction (mRS ≤ 5) using random forest algorithms. Results were compared to conventional pc-ASPECTS and clinical parameters. Models were evaluated in a nested fivefold cross-validation approach.

RESULTS

Receiver operating characteristic areas under the curves (ROC-AUCs) of the test sets using conventionally rated pc-ASPECTS reached 0.63 for mRS ≤ 4 to 0.68 for mRS ≤ 5 and 0.73 for mRS ≤ 5 to 0.85 for mRS ≤ 2 if clinical data were considered. Pure imaging-based machine learning classifier ROC-AUCs were lowest for mRS ≤ 4 (0.81) and highest for mRS ≤ 5 (0.87). The combined clinical data and machine learning-based model had the highest predictive performance with ROC-AUCs reaching 0.90 for mRS ≤ 2.

CONCLUSION

Machine learning-based evaluation of pc-ASPECTS regions predicts functional outcome of pc-stroke patients with higher accuracy than conventional assessments. This could optimize triage for additional diagnostics and allocation of best possible medical care and might allow required arrangements of the social environment at an early point of time.

Endovascular thrombectomy for acute ischemic stroke

This review describes the evolution of endovascular treatment for acute ischemic stroke, current state of the art, and the challenges for the next decade. The rapid development of endovascular thrombectomy (EVT), from the first attempts into standard of care on a global scale, is one of the major achievements in modern medicine. It was possible thanks to the establishment of a scientific framework for patient selection, assessment of stroke severity and outcome, technical development by dedicated physicians and the MedTech industry, including noninvasive imaging for patient selection, and radiological outcome evaluation. A series of randomized controlled trials on EVT in addition to intravenous thrombolytics, with overwhelmingly positive results for anterior circulation stroke within 6 h of onset regardless of patient characteristics with a number needed to treat of less than 3 for any positive shift in outcome, paved the way for a rapid introduction of EVT into clinical practice. Within the "extended" time window of 6-24 h, the effect has been even greater for patients with salvageable brain tissue according to perfusion imaging with a number needed to treat below 2. Even so, EVT is only available for a small portion of stroke patients, and successfully recanalized EVT patients do not always achieve excellent functional outcome. The major challenges in the years to come include rapid prehospital detection of stroke symptoms, adequate clinical and radiological diagnosis of severe ischemic stroke cases, enabling effective recanalization by EVT in dedicated angiosuites, followed by personalized post-EVT stroke care.

Comparative Studies of Cerebral Reperfusion Injury in the Posterior and Anterior Circulations After Mechanical Thrombectomy

Cerebral reperfusion injury is the major complication of mechanical thrombectomy (MT) for acute ischemic stroke (AIS). Contrast extravasation (CE) and intracranial hemorrhage (ICH) are the key radiographical features of cerebral reperfusion injury. The aim of this study was to investigate CE and ICH after MT in the anterior and posterior circulation, and their effect on functional outcome. This is a retrospective study of all consecutive patients who were treated with MT for AIS at University of California Irvine Medical Center between January 1, 2014, and December 31, 2017. Patient characteristics, clinical features, procedural variables, contrast extravasation, ICH, and outcomes after MT were analyzed. A total of 131 patients with anterior circulation (AC) stroke and 25 patients with posterior circulation (PC) stroke underwent MT during the study period. There was no statistically significant difference in admission NIHSS score, blood pressure, rate of receiving intravenous tPA, procedural variables, contrast extravasation, and symptomatic ICH between the 2 groups. Patients with PC stroke had a similar rate of favorable outcome (mRS 0–2) but significantly higher mortality (40.0% vs. 10.7%, p < 0.01) than patients with AC stroke. Multivariate regression analysis identified initial NIHSS score (OR 1.1, CI 1.0–1.2, p = 0.01), number of passes with stent retriever (OR 2.1, CI 1.3–3.6, p < 0.01), and PC stroke (OR 9.3, CI 2.5–35.1, p < 0.01) as independent risk factors for death. There was no significant difference in functional outcomes between patients with and without evidence of cerebral reperfusion injury after MT. We demonstrated that AC and PC stroke had similar rates of cerebral reperfusion injury and favorable outcome after MT. Cerebral reperfusion injury is not a significant independent risk factor for poor functional outcome.

Safety and Efficacy of Endovascular Treatment for Progressive Stroke in Patients With Acute Basilar Artery Occlusion

Background and Purpose: It is unknown the benefit of endovascular therapy (EVT) for progressive stroke in patients with basilar artery occlusion (BAO). The aim of this study was to compare the efficacy and safety of EVT with standard medical therapy (SMT) in a population of BAO patients with progressive stroke.

Methods: The EVT for Acute Basilar Artery Occlusion Study (BASILAR) is a national prospective registry of consecutive patients with acute BAO within 24 h of symptom onset. According to the applied therapy, all patients were divided into SMT and EVT groups. Subsequently, the EVT group was divided into early (≤6 h) and late groups (>6 h) according to the time window. The efficacy outcome was favorable functional outcomes (modified Rankin Scale score ≤ 3) at 90 days. The safety outcomes included mortality within 90 days and symptomatic intracerebral hemorrhage (sICH) after EVT.

Results: The EVT cohort presented more frequently with a favorable functional outcome (adjusted odds ratio, 5.49; 95% confidence interval, 2.06–14.61, p = 0.01) and with a decreased mortality (adjusted odds ratio, 0.3; 95% confidence interval, 0.17–0.54, p < 0.001). What's more, EVT still safe (P = 0.584, P = 0.492, respectively) and effective (P = 0.05) in patients with progressive stroke when the treatment time window exceeds 6 h.

Conclusions: EVT was more effective and safer than SMT for progressive stroke in patients with BAO. Besides, EVT remains safe and effective in patients with progressive stroke when the treatment time window exceeds 6 h. Predictors of desirable outcome in progressive stroke patients undergoing EVT included lower baseline NIHSS score, higher baseline pc-ASPECTs, successful recanalization and shorter puncture to recanalization time.

Endovascular treatment with or without intravenous alteplase for acute ischaemic stroke due to basilar artery occlusion

Background and purpose

It remains controversial if endovascular treatment (EVT) can improve the outcome of patients with acute basilar artery occlusion (BAO). This study aims to compare the functional outcomes between EVT with and without intravenous thrombolysis (IVT) first in patients who had acute ischaemic stroke (AIS) due to BAO.

Methods

Patients who had AIS with BAO who underwent EVT within 24 hours of onset were enrolled in this multicentre cohort study, and the efficacy and safety were compared between IVT+EVT and direct EVT. The primary outcome was 90-day functional independence. All outcomes were assessed with adjusted OR (aOR) from the multivariable logistic regression. In addition, a meta-analysis was performed on all recently published pivotal studies on functional independence after EVT in patients with BAO.

Results

Of 310 enrolled patients with BAO, 241 (78%) were treated with direct EVT and 69 (22%) with IVT+EVT. Direct EVT was associated with a worse functional outcome (aOR, 0.46 (95% CI 0.24 to 0.85), p=0.01). IVT+EVT was associated with a lower percentage of patients who needed ≥3 passes of stent retriever (10.14% vs 20.75%). The meta-analysis regression revealed a potential positive correlation between bridging with IVT first and functional independence (r=0.14 (95% CI 0.05 to 0.24), p<0.01).

Conclusions

This study showed that compared with direct EVT, EVT with IVT first was associated with better functional outcomes in patients with BAO treated within 24 hours of onset. The meta-analysis demonstrated similar favourable efficacy of IVT first followed by EVT in patients with BAO.

Outcomes of Endovascular Therapy in Acute Basilar Artery Occlusion With Severe Symptoms

IMPORTANCE

Endovascular therapy (EVT) has been reported to be safe and effective in improving clinical outcomes among patients with acute basilar artery occlusion (ABAO). The benefits associated with EVT remain uncertain for patients with ABAO with severe symptoms (ie, National Institutes of Health Stroke Scale [NIHSS] score ≥ 21).

OBJECTIVES

To assess the outcomes associated with EVT and identify factors associated with outcomes among patients with ABAO and severe symptoms.

DESIGN, SETTING, AND PARTICIPANTS

This prospective, nationwide cohort study was conducted using data from January 2014 to May 2019 in China from the Endovascular Treatment for Acute Basilar Artery Occlusion Study Registry (BASILAR). Included patients had ABAO and underwent EVT or standard medical treatment (SMT) alone in routine clinical practice. Patients were dichotomized into severe symptoms (ie, NIHSS score ≥ 21) and minor to moderate symptoms (NIHSS score < 21) groups. Patients were followed up for 90 days. Data were analyzed from December 2020 through June 2021.

EXPOSURES

EVT with SMT vs SMT alone.

MAIN OUTCOMES AND MEASURES

The primary outcome was improvement in modified Rankin Scale (mRS) score at 90 days, defined as a decrease by 1 grade in mRS score. Secondary outcomes included favorable functional outcome (ie, mRS score, 0-3) and mortality.

RESULTS

Among 542 patients with ABAO and severe symptoms (median [IQR] age, 65 [57-74] years; 147 [27.1%] women), 431 patients (79.5%) received EVT and 111 patients (20.5%) received SMT. Compared with SMT, EVT was associated with increased odds of improved mRS score (adjusted common odds ratio [OR], 3.44 [95% CI, 2.05-5.78]; P < .001), with increased odds of a favorable functional outcome (ie, mRS score, 0-3; adjusted OR, 4.52 [95% CI, 1.64-12.43]; P = .004) and decreased odds of mortality (adjusted OR, 0.27 [95% CI, 0.15-0.50]; P < .001). Among patients receiving EVT, baseline NIHSS score was associated with decreased odds of a favorable functional outcome (adjusted OR per 1-point increase in score, 0.90 [95% CI, 0.85-0.95]; P < .001) and increased odds of mortality (adjusted OR per 1-point increase in score, 1.13 [95% CI, 1.07-1.19]; P < .001), while posterior circulation Acute Stroke Prognosis Early Computed Tomography Score (pc-ASPECTS) was associated with increased odds of a favorable functional outcome (adjusted OR per 1-point increase in score, 1.71 [95% CI, 1.41-2.07]; P < .001) and decreased odds of mortality (adjusted OR per 1-point increase in score, 0.74 [95% CI, 0.64-0.85]; P < .001). Different occlusion sites, compared with distal basilar artery, were associated with decreased odds of favorable functional outcome (eg, middle basilar artery: adjusted OR vs distal basilar artery, 0.36 [95% CI, 0.17-0.80]; P = .01).

CONCLUSIONS AND RELEVANCE

This study found that EVT was associated with increased odds of functional favorable outcomes among patients with ABAO and severe symptoms. Baseline NIHSS score, pc-ASPECTS, and occlusion site were independent factors associated with clinical outcomes.

Association Between Time to Endovascular Therapy and Outcomes in Patients With Acute Basilar Artery Occlusion

OBJECTIVE

To characterize the association of onset to puncture time (OPT) with clinical outcomes among patients with acute basilar artery occlusion receiving endovascular therapy (EVT) in clinical practice.

METHODS

Using the EVT for Acute Basilar Artery Occlusion (BASILAR) study, we identified consecutive patients with acute basilar artery occlusion receiving EVT in 47 comprehensive stroke centers in China from January 2014 to May 2019. The primary outcome was favorable functional outcome (defined as modified Rankin Scale score [mRS] 0-3) at 90 days. Secondary outcomes included function independence (mRS 0-2), mortality, and symptomatic intracerebral hemorrhage. The associations of OPT with clinical outcomes were analyzed using multivariable logistic regression (OPT as a categorical variable) and restricted cubic spline regression (OPT as a continuous variable).

RESULTS

Among 639 eligible patients, the median age was 64 years, and median OPT was 328 minutes (interquartile range 220-490). Treatment within 4-8 hours and 8-12 hours was associated with lower rates of favorable outcome (adjusted odds ratio, 0.63 [95% confidence interval (CI), 0.40-0.98] and 0.47 [95% CI, 0.23-0.93], respectively) compared with treatment within 4 hours. Restricted cubic spline regression analysis showed that the OPT had L-shaped associations with favorable outcome (p _nonlinearity = 0.028) and functional independence (p _nonlinearity = 0.025), with significant benefit loss throughout the first 9 hours, but then appeared relatively flat. The odds of mortality increased relatively for OPT up to 9 hours, but then leveled off (p _nonlinearity = 0.042). The association between symptomatic intracerebral hemorrhage and OPT was not significant.

CONCLUSION

Among patients with acute basilar artery occlusion in routine practice, earlier treatment with EVT was associated with better outcomes throughout the first 9 hours after onset, but benefit may sustain unchanged afterwards.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that for patients with acute ischemic stroke due to basilar artery occlusion, earlier EVT is associated with better outcomes.

Perfusion Imaging Predicts Favorable Outcomes after Basilar Artery Thrombectomy

OBJECTIVE

Perfusion imaging identifies anterior circulation stroke patients who respond favorably to endovascular thrombectomy (ET), but its role in basilar artery occlusion (BAO) is unknown. We hypothesized that BAO patients with limited regions of severe hypoperfusion (time to reach maximum concentration in seconds [Tmax] > 10) would have a favorable response to ET compared to patients with more extensive regions involved.

METHODS

We performed a multicenter retrospective cohort study of BAO patients with perfusion imaging prior to ET. We prespecified a Critical Area Perfusion Score (CAPS; 0-6 points), which quantified severe hypoperfusion (Tmax > 10) in cerebellum (1 point/hemisphere), pons (2 points), and midbrain and/or thalamus (2 points). Patients were dichotomized into favorable (CAPS ≤ 3) and unfavorable (CAPS > 3) groups. The primary outcome was a favorable functional outcome 90 days after ET (modified Rankin Scale = 0-3).

RESULTS

One hundred three patients were included. CAPS ≤ 3 patients (87%) had a lower median National Institutes of Health Stroke Scale score (NIHSS; 12.5, interquartile range [IQR] = 7-22) compared to CAPS > 3 patients (13%; 23, IQR = 19-36; p = 0.01). Reperfusion was achieved in 84% of all patients, with no difference between CAPS groups (p = 0.42). Sixty-four percent of reperfused CAPS ≤ 3 patients had a favorable outcome compared to 8% of nonreperfused CAPS ≤ 3 patients (odds ratio [OR] = 21.0, 95% confidence interval [CI] = 2.6-170; p < 0.001). No CAPS > 3 patients had a favorable outcome, regardless of reperfusion. In a multivariate regression analysis, CAPS ≤ 3 was a robust independent predictor of favorable outcome after adjustment for reperfusion, age, and pre-ET NIHSS (OR = 39.25, 95% CI = 1.34->999, p = 0.04).

INTERPRETATION

BAO patients with limited regions of severe hypoperfusion had a favorable response to reperfusion following ET. However, patients with more extensive regions of hypoperfusion in critical brain regions did not benefit from endovascular reperfusion. ANN NEUROL 2021.

Mechanical Thrombectomy for Anterior versus Posterior Circulation Large Vessel Occlusion Stroke with Emphasis on Posterior Circulation Outcomes

PURPOSE

Although there is class I evidence for mechanical thrombectomy (MT) for anterior circulation large vessel occlusion (LVO) stroke, no high-class evidence exists for the posterior circulation. Here, we sought to compare clinical features of anterior versus posterior LVO as well as predictors of a posterior LVO MT outcome.

METHODS

Patients with acute ischemic stroke who underwent MT for anterior and posterior LVO stroke between February 2016 and August 2020 from 2 comprehensive stroke centers were reviewed. Anterior and posterior LVO strokes were compared. In addition, predictors for a favorable outcome (modified Rankin scale [mRS] 0-3), death (mRS 6), and futile revascularization (mRS 4-6 despite TICI 2b/3 revascularization) for posterior LVO were analyzed.

RESULTS

Collectively, 813 LVO thrombectomy cases were analyzed, and 77 of 813 cases (9.5%) were located in the posterior circulation. Although favorable 90-day functional outcome rates did not differ between anterior and posterior LVO (P = 0.093), death was significantly more frequent among posterior LVO cases (P = 0.013). In the posterior LVO subgroup, a primary aspiration technique and successful revascularization TICI 2b/3 irrespective of time to the intervention were independently associated with achieving a favorable outcome. Primary aspiration was identified to inversely associate with futile revascularization.

CONCLUSION

Anterior and posterior circulation MT patients have distinct clinical profiles. The use of primary aspiration appears fundamental for beneficial outcomes in posterior circulation MT.

Cerebral blood volume index as a predictor of functional independence after basilar artery thrombectomy

BACKGROUND AND PURPOSE

The role of CT perfusion (CTP)in the evaluation of acute basilar artery occlusion (aBAO) patients undergoing endovascular thrombectomy (EVT) is unclear. We investigated the association of individual CTP parameters with functional outcomes in aBAO patients undergoing EVT.

METHODS

A health system's prospectively collected code stroke registry was used in this retrospective analysis of aBAO patients treated with EVT presenting between January 2017 and February 2021 with pre-EVT CTP. The primary outcome measure was modified Rankin Scale (mRS) score 0-2 at 90 days. Factors with a univariate association (p < .05) with mRS 0-2 were combined in a multivariable regression model to determine independent predictors of 90-day favorable functional outcome.

RESULTS

Forty-six subjects, with median age 67 years and median National Institutes of Health Stroke Scale 16, were included, of whom 17 (37%) achieved mRS 0-2 at 90 days. In the multivariable logistic regression model, CTP cerebral blood volume (CBV) index (per 0.1-point increase, odds ratio = 1.843; 95% confidence interval: 1.039, 3.268; p-value .0365) was independently associated with a favorable 90-day outcome.

CONCLUSIONS

CBV index was independently associated with a favorable 90-day outcome in aBAO patients treated with EVT, a novel finding in this patient population. CBV index may assist in treatment and prognosis discussions and inform future studies investigating the role of CTP in aBAO.

Stent Retriever Thrombectomy for Anterior vs. Posterior Circulation Ischemic Stroke: Analysis of the STRATIS Registry

Background and Purpose: The benefits of mechanical thrombectomy (MT) in vertebrobasilar artery occlusions have not been well-studied. We compared clinical, procedural, and safety outcomes of MT for posterior circulation (PC) vs. anterior circulation (AC) occlusions among patients in the STRATIS registry.

Methods: Data from STRATIS including patient demographics, procedural characteristics, and outcomes including symptomatic intracranial hemorrhage (sICH) at 24 h, serious adverse events (SAE), substantial reperfusion [modified thrombolysis in cerebral infarction (mTICI) 2b/3], 90-day functional independence [modified Rankin Scale (mRS) 0–2], and 90-day mortality were analyzed. Univariate logistic regression was used to calculate predictors of good clinical outcome.

Results: Of 984 STRATIS patients, 43 (4.4%) patients with PC occlusions [mean age 63.0 ± 13.6, 25.6% (11/43) female] and 932 (94.7%) with AC occlusions [mean age 68.5 ± 14.8, 46.9% (437/932) female] were included for analysis. Median National Institutes of Health Stroke Scale (NIHSS) scores at baseline were 17.0 (13.0, 12.0) for the AC group and 12.0 (11.0, 24.0) for the PC group. Time from onset to procedure end was longer for the PC group [median (IQR): 322.0 min (255.0–421.0) vs. 271.0 min (207.0–360.0); p = 0.007]. PC and AC groups had similar rates of substantial reperfusion [89.2% (33/37) vs. 87.7% (684/780)], procedure-related SAE [0.0% (0/43) vs. 1.7% (16/932)], sICH [0.0% (0/38) vs. 1.5% (12/795)], 90-day functional independence [66.7% (26/39) vs. 55.9% (480/858)] and mortality [12.8% (5/39) vs. 15.8% (136/861)]. National Institutes of Health Stroke Scale score and patient sex were significant univariate predictors of good clinical outcome (p < 0.05).

Conclusions: Despite longer reperfusion times, MT in PC stroke has similar rates of 90-day functional independence with no significant difference in procedure-related SAE, sICH, or mortality, supporting the use of MT in PC acute ischemic stroke (AIS).

Clinical Trial Registration:https://www.clinicaltrials.gov, Identifier: NCT02239640.

Endovascular Thrombectomy Treatment: Beyond Early Time Windows and Small Core

ABSTRACT

Tremendous advancements in the treatment of acute ischemic stroke in the last 25 years have been based on the principle of reperfusion in early time windows and identification of small core infarct for intravenous thrombolysis and mechanical thrombectomy. Advances in neuroimaging have made possible the safe treatment of patients with acute ischemic stroke in longer time windows and with more specific selection of patients with salvageable brain tissue. In this review, we discuss the history of endovascular stroke thrombectomy trials and highlight the neuroimaging-based trials that validated mechanical thrombectomy techniques in the extended time window with assessment of penumbral tissue. We conclude with a survey of currently open trials that seek to safely expand eligibility for this highly efficacious treatment.

Endovascular treatment for basilar artery occlusion: A systematic review and meta-analysis

BACKGROUND AND PURPOSE

Independent randomized controlled clinical trials (RCTs) have provided robust evidence for endovascular treatment (EVT) as the standard of care treatment for acute large vessel occlusions in the anterior circulation. We examined available studies specific to posterior cerebral circulation ischemic strokes to see if any conclusions can be drawn regarding EVT options.

METHODS

We performed a systematic literature search to identify studies evaluating the safety and efficacy of EVT versus standard medical treatment for patients with acute basilar artery occlusion (BAO). We extracted data for outcomes of interest and presented associations between the two groups with the use of risk ratios (RRs) or odds ratios (ORs), with corresponding 95% confidence intervals (CIs). We used a random-effects model to pool the effect estimates.

RESULTS

We identified five studies (two RCTs, three observational cohorts) including a total of 1098 patients. Patients receiving EVT had a higher risk of symptomatic intracranial hemorrhage (sICH) compared to those receiving non-interventional medical management (RR 5.42, 95% CI 2.74-10.71). Nonsignificant trends towards modified Rankin Scale (mRS) scores 0-2 (RR 1.02, 95% CI 0.74-1.41), mRS scores 0-3 (RR = 0.97, 95% CI 0.64-1.47), overall functional improvement (OR 0.93, 95% CI 0.57-1.51), and all-cause mortality (RR 1.03, 95% CI 0.78-1.35) at 3 months were seen.

CONCLUSION

Although EVT increases the probability of sICH, the available data do not exclude the possibility of improved functional outcomes over standard therapy. As larger studies are challenged by the perceived lack of equipoise in this vulnerable patient population, results of ongoing RCTs are expected to provide substantial input for future meta-analyses.

Comparisons of Characteristics and Outcomes after Mechanical Thrombectomy for Vertebrobasilar Occlusion with Cardioembolism or Atherosclerotic Brain Infarction: Data from the Tokyo-Tama-Registry of Acute Endovascular Thrombectomy (TREAT)

BACKGROUND

Some reports suggest the efficacy of mechanical thrombectomy (MT) for acute vertebrobasilar artery (VBA) occlusion. The major causes of VBA occlusion include cardioembolism (CE) and large-artery atherosclerosis (LAA). However, the clinical characteristics of each cause remain unclear, and they might be important for decision making related to the indications and strategy of MT.

OBJECTIVE

This study aimed to compare functional outcomes and factors affecting outcomes between patients with CE and LAA with acute VBA occlusion.

METHODS

This was a retrospective and prospective observational study using data from TREAT (Tokyo-Tama-Registry of Acute Endovascular Thrombectomy), a multicenter registry of MT for acute large-vessel occlusion in the Tokyo metropolitan area. Patients with VBA occlusion classified into CE and LAA groups were analyzed. The primary outcome was a modified Rankin Scale score of 0-2 at 90 days.

RESULTS

Seventy-nine patients (57 with CE and 22 with LAA) were eligible from January 2015 to March 2020. Despite significantly shorter puncture-to-recanalization and onset-or-last-well-known-to-recanalization times in the CE group, the primary outcome was not significantly different between the 2 groups (CE, 31.6% vs. LAA, 45.5%; P = 0.248). In the subgroup analysis, patients with CE had worse clinical outcomes in the onset-or-last-well-known-to-door time ≥180 minutes, onset-or-last-well-known-to-door time ≥300 minutes, and low posterior circulation Alberta Stroke Program Early CT Score (≤7) subgroups.

CONCLUSIONS

Functional outcomes of VBA occlusion were not significantly different between CE and LAA. Based on the subgroup analysis, patients with CE might have poorer collateral status than do patients with LAA, and earlier recanalization might therefore be desired.

Endovascular Mechanical Thrombectomy for Basilar Artery Occlusion Caused by Thrombosis as an Initial Manifestation of Acute Myelogenous Leukemia: A Case Report

We report a rare case of a basilar artery occlusion (BAO) caused by thrombosis as an initial magnification of acute myelogenous leukemia (AML) and performed mechanical thrombectomy (MT) to treat it. A 67-year-old female presented left hemiparalysis of her arm and right-sided blindness. Magnetic resonance imaging (MRI) and magnetic resonance angiography revealed acute infarction in the left occipital and anterior lobes of the cerebellum and incomplete BAO. Her blood test showed hyperleukocytosis with precursor cells and high levels of C-reactive protein, and we diagnosed AML and disseminated intravascular coagulation (DIC). We decided to treat conservatively with rapid rehydration and heparin, but three hours after admission, she suddenly lost consciousness. We performed acute MT with a direct aspiration first-pass technique (ADAPT). A white elastic embolus was aspirated, and DSA showed successful recanalization of the basilar artery. The next day, MRI revealed acute infarction in the midbrain and bilateral thalamus. The patient remained unconscious after MT and so chemotherapy to treat the acute leukemia could not be performed. The patient died of the primary disease 14 days after BAO. Thrombosis in association with AML is very rare disease and could occur in arterial vessels because of hypercoagulation, and this tendency may not respond to anticoagulation therapy. Although ADAPT might be performed safety without complications even in cases of DIC, indications for treatment with MT should be carefully considered in patients in whom hemorrhage is a possibility.

A New Angiographic Collateral Grading System for Acute Basilar Artery Occlusion Treated with Endovascular Therapy

Poor clinical outcomes despite endovascular therapy (EVT) are common in patients with acute basilar artery occlusion (BAO). We aimed to develop a new angiographic collateral grading system for predicting 90-day functional outcomes of acute BAO after EVT. A prospectively registered consecutive cohort of acute BAO patients treated with EVT in our center during a 6-year period was reviewed. The angiographic collateral grading system for BAO (ACGS-BAO) included 4 grades for poor (grade 1-2), intermediate (grade 3), and good (grade 4) collateral statuses. First, the independent association of ACGS-BAO with 90-day functional independence (mRS ≤ 2), favorable outcome (mRS ≤ 3), and death was evaluated by multivariable logistic regression model; then, the heterogeneity in the effects of ACGS-BAO on 90-day outcomes was explored among the subgroups stratified by age, time window, stroke severity, and etiology. Finally, the interobserver agreement of ACGS-BAO was assessed by weighted kappa statistic. Of 173 patients included in this study, 62 (35.8%), 83 (48.0%), and 36 (20.8%) achieved 90-day functional independence, favorable outcome, and death, respectively. Multivariable logistic analyses showed that ACGS-BAO was independently associated with functional independence (OR = 2.07, 95% CI = 1.05-4.07) and favorable outcome (OR = 1.84, 95% CI = 1.02-3.43) but not related to death (OR = 0.78, 95% CI = 0.37-1.64). Similar effects of ACGS-BAO on 90-day outcomes were seen across all subgroups (P > 0.10 for all interactions). The interobserver agreement of ACGS-BAO was very high (weighted kappa = 0.96, 95% CI = 0.93-0.99). The ACGS-BAO is an angiographic tool with excellent interobserver reliability that can be used to predict the 90-day outcome of acute BAO treated by EVT. Nevertheless, our findings are still needed to be confirmed in a prospective multicenter study before clinical application.

Cerebral collaterals in acute ischaemia: Implications for acute ischaemic stroke patients receiving reperfusion therapy

The cerebral collaterals play an important role in penumbral tissue sustenance after an acute ischaemic stroke. Recent studies have demonstrated the potential role of collaterals in the selection of acute ischaemic stroke patients eligible for reperfusion therapy. However, the understanding of the significance and evidence around the role of collateral status in predicting outcomes in acute ischaemic stroke patients treated with reperfusion therapy is still unclear. Moreover, the use of pre-treatment collaterals in patient selection and prognosis is relatively underappreciated in clinical settings. A focused review of the literature was performed on the various methods of collateral evaluation and the role of collateral status in acute ischaemic stroke patients receiving reperfusion therapy. We discuss the methods of evaluating pre-treatment collaterals in clinical settings. The patient selection based on collateral status as well as the prognostic and therapeutic value of collaterals in acute ischaemic stroke, in settings of intravenous thrombolysis or endovascular therapy alone, and bridge therapy, are summarized. Recommendations for future research and possible pharmacological intervention strategies aimed at collateral enhancement are also discussed. Collaterals may play an important role in identifying acute ischaemic stroke patients who are likely to benefit from endovascular treatment in an extended time window. Future neuroscientific efforts to better improve our understanding of the role of collaterals in acute ischaemia as well as clinical studies to delineate its role in patient selection and acute stroke prognosis are warranted.