The Basilar Artery International Cooperation Study (BASICS): study protocol for a randomised controlled trial

Endovascular Treatment for Basilar Artery Occlusion

Basilar artery occlusion (BAO) is a neurological emergency associated with a high risk for adverse outcomes. This review provides evidence on the therapeutic efficacy of intravenous thrombolysis (IVT) and endovascular therapy (EVT) in the treatment of BAO. Historically considered the primary intervention for acute ischemic stroke, IVT has been progressively combined with EVT, which has emerged from recent studies demonstrating clinical benefits, notably in patients presenting with severe stroke. Several randomised controlled trials have shown that EVT improves patient outcomes in select clinical contexts. Future research directions could address therapeutic treatment thresholds, combination strategies, and long-term outcomes.

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.

Platelet indices as prognostic markers of ischemic stroke and their correlation with lipid profile

OBJECTIVE

Stroke is the cause of one in eight deaths and adds a dreadful burden of disability for the patients. Ischemic stroke is caused by a loss of blood supply to brain due to sudden occlusion of the arterial system, caused by an emboli or thrombus. Our aim was to correlate platelet indices, total cholesterol ratio, and various comorbidities with stroke.

METHODS

A cross-sectional study was performed from 2020-2022 with 132 stroke patients admitted to the SRM Medical College Hospital and Research Center, India. Detailed clinical examination was performed. Venous blood samples were drawn at the time of admission to estimate platelet count, mean platelet volume (MPV), platelet distribution width (PDW), and platelet crit (PCT). Overnight fasting serum samples were obtained for lipid profiling.

RESULTS

Among the participants in our study, maximum belonged to the age group 50 to 59 years (34.1%) and majority were males (79.5%). In terms of comorbidities, 85.6% of the participants had diabetes, 42.4% had hypertension and 22% had dyslipaedemia. All platelet and lipid parameters were found to be similar between patients with and without comorbidities. While all platelet indices increased with the increase in severity of stroke, we found that PDW is most reliable in predicting stroke with an area under the receiver operator curve of 0.942, with a sensitivity and specificity of 92.1% at cut-off value 14. All platelet parameters also significantly increased in patients with severe lipid dysfuction, establishing a correlation between lipid profile, platelet indices and stroke.

CONCULSION

We found a significant relationship between all platelet parameters and stroke. Thus, we believe that patients with risk factors for atherosclerosis should have their platelet indices assessed periodically before the development of cerebrovascular events. Furthermore, dyslipidemia if properly treated, is a modifiable risk factor for stroke, which can decrease morbidity and mortality leading to a healthier society.

Outcome prediction value of critical area perfusion score for acute basilar artery occlusion

PURPOSE

To investigate the performance of the Critical Area Perfusion Score (CAPS), based on computed tomography perfusion (CTP) time to maximum (Tmax) > 10s maps, to predict the outcome in acute basilar artery occlusion (BAO) in patients undergoing endovascular treatment (EVT).

METHODS

We perform a retrospective analysis of a prospectively collected database of acute BAO treated with EVT in a comprehensive stroke center. The favorable outcome was defined as the 90-day modified Rankin Scale (mRS) ≤ 3. We performed the logistic regression analysis to find the independent predictors of the favorable outcome. Then, we used receiver operating characteristic analyses to assess the predictive value of the imaging parameters, including CAPS, Posterior Circulation Alberta Stroke Program Early CT Score (PC-ASPECTS), pons midbrain index (PMI), posterior circulation computed tomography angiography (PC-CTA) score, Basilar Artery on Computed Tomography Angiography (BATMAN) score, and CTP parameters. Finally, the Delong test was used to compare the area under the curve (AUC) of CAPS against the other imaging parameters.

RESULTS

Of the 65 enrolled patients, the incidence of the favorable outcome was 44.6% (29/65). Low CAPS (per 1- point increased odds ratio [OR], 0.43; 95% confidence interval [CI], 0.22-0.86; P = 0.017) and admission National Institutes of Health Stroke Scale (NIHSS) (per 1- point increased OR, 0.80; 95% CI, 0.70-0.91; P = 0.001) were independently associated with favorable outcome. The AUC of CAPS was 0.83 (95% CI, 0.74-0.93; P < 0.001) with ≤ 3 cut-off value, 89.66% sensitivity, 77.22% specificity, and 80.00% accuracy, which was greater than the other imaging parameters (All P for Delong test < 0.05).

CONCLUSIONS

CAPS was the most accurate imaging-based outcome predictor in acute BAO patients. Future large prospective multicenter studies are needed to verify these results.

Early Intubation in Endovascular Therapy for Basilar Artery Occlusion: A Post Hoc Analysis of the BASICS Trial

BACKGROUND

The optimal anesthetic management for endovascular therapy (EVT) in patients with posterior circulation stroke remains unclear. Our objective was to investigate the impact of early intubation in patients enrolled in the BASICS trial (Basilar Artery International Cooperation Study).

METHODS

BASICS was a multicenter, randomized, controlled trial that compared the efficacy of EVT compared with the best medical care alone in patients with basilar artery occlusion. In this post hoc analysis, early intubation within the first 24 hours of the estimated time of basilar artery occlusion was examined as an additional covariate using regression modeling. We estimated the adjusted relative risks (RRs) for favorable outcomes, defined as modified Rankin Scale scores of 0 to 3 at 90 days. An adjusted common odds ratio was estimated for a shift in the distribution of modified Rankin Scale scores at 90 days.

RESULTS

Of 300 patients in BASICS, 289 patients were eligible for analysis (151 in the EVT group and 138 in the best medical care group). compared with medical care alone, EVT was related to a higher risk of early intubation (RR, 1.29 [95% CI, 1.09-1.53]; P<0.01), and early intubation was negatively associated with favorable outcome (RR, 0.61 [95% CI, 0.45-0.84]; P=0.002). Whereas there was no overall treatment effect of EVT on favorable outcome (RR, 1.22 [95% CI, 0.95-1.55]; P=0.121), EVT was associated with favorable outcome (RR, 1.34 [95% CI, 1.05-1.71]; P=0.018) and a shift toward lower modified Rankin Scale scores (adjusted common odds ratio, 1.63 [95% CI, 1.04-2.57]; P=0.033) if adjusted for early intubation.

CONCLUSIONS

In this post hoc analysis of the neutral BASICS trial, early intubation was linked to unfavorable outcomes, which might mitigate a potential benefit from EVT by indirect effects due to an increased risk of early intubation. This relationship may be considered when assessing the efficacy of EVT in patients with basilar artery occlusion in future trials.

Exploring the Multifaceted Causes of Ischemic Stroke: A Narrative Review

Neurologists are well-versed with acute ischemic stroke, a serious public health concern. Effective acute stroke treatment is built on the rapid application of reperfusion therapy. This calls for prompt symptom recognition by the general population as well as emergency workers, proper referral to specialized stroke centers, and thorough examination and assessment by the on-site stroke team. The main goal of treatment for certain individuals is to restore blood flow to the ischemic penumbra by using intravenous thrombolysis and/or endovascular thrombectomy. Acute stroke patients must be hospitalized and continuously monitored for early neurological decline in order to avoid subsequent problems. After swiftly determining the stroke mechanism, patients can start the proper secondary preventative actions.

The Efficacy and Safety of Mechanical Thrombectomy in Posterior Circulation Large Vessel Occlusion as Compared to Anterior Circulation Large Vessel Occlusion: A Systematic Review

Mechanical thrombectomy (MT) has been established as a standard of care for patients with stroke due to anterior circulation large vessel occlusion (AC-LVO). Due to a lack of robust evidence for the effectiveness of mechanical thrombectomy, intravenous thrombolysis (IVT) is still the only approved first-line acute reperfusion strategy for posterior circulation large vessel occlusion (PC-LVO). This systematic review analyzes and reports on the effectiveness and safety of MT in PC-LVO. A literature review was performed to identify all studies of patients with acute ischemic stroke due to PC-LVO who underwent MT with second-generation devices (stent retrievers and/or aspiration devices) that were reported between January 2017 and January 2023. The primary outcome was functional independence at 90 days, defined as a modified Rankin (mRS) score of ≤2. Secondary outcomes were successful recanalization (modified treatment in cerebral infarction score (mTICI) 2b/3), symptomatic intracerebral hemorrhage (sICH), and mortality at 90 days post-procedure. We looked at 13 studies with a total of 30,407 participants in four meta-analyses and 5951 participants in nine observational studies. In most studies, patients in the PC-LVO group were male and younger than the AC-LVO group. Higher baseline National Institutes of Health Stroke Scale (NIHSS) score, lower rates of IVT, longer onset-to-groin puncture time, lower likelihood of sICH, higher 90-day mortality rates, and higher futile recanalization rates were frequently observed in the PC-LVO group with a large discrepancy in the likelihood of functional independence at 90 days with majority studies showing comparable rates. Hence, in patients with acute ischemic stroke caused by the PC-LVO, successful reperfusion can be achieved via MT, though at the cost of higher mortality rates. Such futile recanalization can be avoided with the refinement of procedures through technical improvements, skills training, and recognition of reliable predictors associated with it, which might help increase the efficacy of MT in PC-LVO. Additionally, future large-scale RCTs comparing patient selection and interventional strategies to avoid futile interventions are also needed.

Effect of massive cerebellar infarction on the outcomes of patients with acute basilar artery occlusion during hospitalization after endovascular treatment: A retrospective study

Acute basilar artery occlusion (ABAO) after endovascular treatment (EVT) is often associated with a poor prognosis, particularly in patients with cerebellar infarction who may develop malignant cerebellar edema. The present study aimed to investigate how massive cerebellar infarction (MCI) affects hospitalization outcomes in ABVO patients who undergo EVT. We conducted a retrospective study of ABVO patients who underwent EVT at our hospital between September 2017 and September 2022. MCI was diagnosed using imaging techniques, and various prognostic scores were assessed during hospitalization to examine the relationship between MCI and these outcomes. We identified 42 ABAO patients, of whom 22 (52.4%) had MCI. Patients with MCI had a higher modified Rankin Scale (mRS) score at discharge compared to those without MCI (4.36 ± 1.14 vs 3.05 ± 1.85, P = .042, odds ratio [OR] (95% confidence interval [CI]) = 1.093 (0.083, 2.103)), and a lower Glasgow Coma Scale score (6.59 ± 4.0 vs 10.10 ± 5.07, P = .036, OR (95% CI) = -3.444 (-6.518, -0.369)). MCI was identified as an independent risk factor for an extremely poor prognosis (mRS ≥ 5) at discharge (P = .036, OR (95% CI) = 15.531 (1.603, 313.026)) and for no improvement in mRS score compared to onset (P = .013, OR (95% CI) = 0.025 (0.001, 0.274)). Additionally, an extremely poor prognosis was independently associated with stent implantation, EVT duration, and body mass index, while mRS score improvement was correlated with EVT duration and pulmonary infection. MCI in ABAO patients is a significant independent risk factor for a poor prognosis at discharge and no improvement in function score compared to onset. Early diagnosis and intervention are necessary to improve outcomes, particularly in high-risk populations.

Single-center experience of endovascular treatment for patients with progressive posterior circulation cerebral infarction exceeding 24 h

Background

Evidence of endovascular treatment (ET) for patients with progressive infarction of the posterior circulation exceeding 24 h is lacking.

Objective

To evaluate the efficacy and safety of ET for progressive posterior circulation cerebral infarction.

Methods

This retrospective study evaluated the ET for 18 patients with posterior circulation infarction caused by vertebrobasilar artery occlusion from July 2017 to November 2018. The conditions of patients worsened despite receiving intravenous thrombolysis or combination therapy with clopidogrel and aspirin. The time from the onset of cerebral infarction to puncture was >24 h. The preoperative National Institutes of Health Stroke Scale (NIHSS), modified Rankin Scale (mRS), and related risk factors of patients at 3 months were analyzed postoperatively.

Results

The preoperative NIHSS score was 10.6 (IQR: 6.5), and the time from onset to puncture was 163.5 ± 144.7 h. Postoperative blood flow was modified thrombolysis in cerebral infarction (mTICI) grade 2b or above. During the follow-up period, 1 patient died of basilar artery re-occlusion and pulmonary infection, and 1 died of postoperative hyperperfusion hemorrhage, with a mortality rate of 11.1% (2/18). No recurrent ischemic events were observed in any of the 16 patients during the 3-month follow-up period. The mean mRS score was 1.3 (IQR: 2.3), and 75% patients (12/16) had an mRS score of 0-2. There were no significant differences in age, gender, clinical characteristics, and stroke subtype between patients with mRS scores ≤2 and >2.

Conclusion

In patients with progressive posterior circulation cerebral infarction caused by vertebral basilar artery occlusion, ET is effective and safe even if the time from onset to puncture exceeds 24 h.

Functional recovery continues beyond 3 months post-basilar artery thrombectomy: A retrospective cohort study

INTRODUCTION

Untreated basilar artery occlusion (BAO) carries 70% mortality. Guidelines recommend thrombectomy with or without thrombolysis.

AIM

We compared Modified Rankin Scores (mRS) at 3 and 12 months post thrombectomy to determine benefit of long-term follow up.

METHODS

Retrospective, single centre analysis of BAO thrombectomies between 2015 and 2019. Inclusion criteria were symptomatic BAO on CT angiography, absent early ischemic changes, premorbid independence and intervention within 24 h. All received stroke ward care. Results were analysed with simple statistics and binary logistic regression as appropriate.

RESULTS

Of 82 patients: most were male (61%, 50/82) with median age 68 years (IQR 17 years) and median NIHSS 14 (IQR 15). Median door-to-puncture time was 42 min (IQR 72 min). Total deaths were 34.1% (28/82) at 3 months, and 37.8% (31/82) at 12 months. Of 51 patients alive at 12 months: 41% (21/51) had improved mRS, 16% (8/51) had worse mRS and 43% (22/51) had unchanged mRS, compared to 3 months. Improvements to mRS were: one point in 57.1% (14/21), two points in 28.9% (6/21) and three points in 4.8% (1/21). Nursing home admission was avoided in 11.8% (6/51) who improved from mRS4. Increased age was associated with decreased likelihood of reaching the primary outcome OR 0.87, 95% CI 0.76-0.99 (p value = 0.03).

CONCLUSION

Over a quarter of patients improved beyond 3 months. Future studies should adopt long-term follow up as primary outcome.

Prognostic value of pretreatment diffusion-weighted imaging score for acute basilar artery occlusion with successful endovascular recanalization

PURPOSE

The aim of this study is to test the prognostic value of a diffusion-weighted imaging (DWI) score in acute basilar artery occlusion (ABAO) with successful recanalization.

METHODS

The DWI-based pons-midbrain and thalamus (PMT) score was developed to assess posterior circulation infarcts. We test its prognostic value and compare it with other two established scales, the DWI-based posterior circulation acute stroke prognosis Early CT score (PC-ASPECTS) and brain stem score (BSS). A retrospective cohort of consecutive ABAO patients with pretreatment magnetic resonance imaging and successful recanalization (defined as modified Thrombolysis in Cerebral Infarction 2b-3) were analyzed. A favorable outcome was defined as a 90-day modified Rankin Scale (mRS) score of 2 or less. The prognostic performance of three scales was estimated by receiver operating characteristic (ROC) curve analyses.

RESULTS

One hundred and sixteen eligible patients (mean age, 59.1 ± 11.7 [standard deviation]; 96 [82.8%] man) were included and evaluated. Between favorable (mRS ≤ 2) and unfavorable groups, the baseline PMT score (median [interquartile range], 3 [1-4] versus 6 [5-8]; P < 0.001) differs significantly. ROC curve analyses showed the PMT score had the best prognostic value for favorable outcome (area under the curve, PMT versus BSS versus PC-ASPECTS = 0.80 versus 0.72 versus 0.68, P = 0.010). Multivariate logistic regression analyses showed baseline National Institute of Health stroke scale (OR, 0.90 [95%CI, 0.86-0.95], P = 0.004) and PMT score < 5 (OR, 17.83 [95%CI, 3.91-81.19], P < 0.001) were independent prognostic factors of favorable outcome.

CONCLUSIONS

The PMT score seems to predict clinical outcome of ABAO patients with successful recanalization.

Endovascular thrombectomy for basilar artery occlusion stroke: Analysis of the German Stroke Registry-Endovascular Treatment

BACKGROUND AND PURPOSE

Acute ischemic stroke due to basilar artery occlusion (BAO) causes the most severe strokes and has a poor prognosis. Data regarding efficacy of endovascular thrombectomy in BAO are sparse. Therefore, in this study, we performed an analysis of the therapy of patients with BAO in routine clinical practice.

METHODS

Patients enrolled between June 2015 and December 2019 in the German Stroke Registry-Endovascular Treatment (GSR-ET) were analyzed. Primary outcomes were successful reperfusion (modified Thrombolysis in Cerebral Infarction [mTICI] score of 2b-3), substantial neurological improvement (≥8-point National Institute of Health Stroke Scale [NIHSS] score reduction from admission to discharge or NIHSS score at discharge ≤1), and good functional outcome at 3 months (modified Rankin Scale [mRS] score of 0-2).

RESULTS

Out of 6635 GSR-ET patients, 640 (9.6%) patients (age 72.2 ± 13.3, 43.3% female) experienced BAO (median [interquartile range] NIHSS score 17 [8, 27]). Successful reperfusion was achieved in 88.4%. Substantial neurological improvement at discharge was reached by 45.5%. At 3-month follow-up, good clinical outcome was observed in 31.1% of patients and the mortality rate was 39.2%. Analysis of mTICI3 versus mTICI2b groups showed considerable better outcome in those with mTICI3 (38.9% vs. 24.4%; p = 0.005). The strongest predictors of good functional outcome were intravenous thrombolysis (IVT) treatment (odds ratio [OR] 3.04, 95% confidence interval [CI] 1.76-5.23) and successful reperfusion (OR 4.92, 95% CI 1.15-21.11), while the effect of time between symptom onset and reperfusion seemed to be small.

CONCLUSIONS

Acute reperfusion strategies in BAO are common in daily practice and can achieve good rates of successful reperfusion, neurological improvement and good functional outcome. Our data suggest that, in addition to IVT treatment, successful and, in particular, complete reperfusion (mTICI3) strongly predicts good outcome, while time from symptom onset seemed to have a lower impact.

Outcome of endovascular treatment in acute basilar artery occlusion with National Institutes of Health Stroke Scale score 10-19

OBJECTIVE

Authors of this study aimed to investigate the efficacy and safety of endovascular treatment (EVT) versus standard medical treatment (SMT) alone in patients with acute basilar artery occlusion (BAO) and moderate deficit (National Institutes of Health Stroke Scale [NIHSS] score 10-19).

METHODS

Patients with moderate deficit caused by acute BAO in the period from January 2014 to May 2019 were included in the study. The patients were divided into groups based on treatment: EVT plus SMT group or SMT-alone group. The primary outcome was favorable functional outcome (modified Rankin Scale score 0-3) at 90 days, and safety outcomes were symptomatic intracerebral hemorrhage (sICH) and mortality at 90 days.

RESULTS

A total of 173 patients had moderate deficits, 128 of whom had been treated with EVT and 45 with SMT alone. EVT was associated with a significant higher proportion of 90-day favorable outcomes compared with SMT (adjusted odds ratio [aOR] 4.09, 95% CI 1.39-12.04, p = 0.011). Younger age (aOR 0.96, 95% CI 0.92-0.99, p = 0.017), absence of diabetes mellitus (aOR 0.35, 95% CI 0.12-0.99, p = 0.048), higher baseline posterior circulation Acute Stroke Prognosis Early Computed Tomography Score (pc-ASPECTS; aOR 1.48, 95% CI 1.07-2.05, p = 0.018), and modified Thrombolysis in Cerebral Infarction (mTICI) score of 2b-3 (aOR 15.15, 95% CI 3.07-74.72, p = 0.001) were independent factors for a favorable outcome in the EVT group. Rates of mortality and sICH were comparable in the EVT and SMT groups.

CONCLUSIONS

EVT leads to improved outcomes compared to those with SMT alone. Younger age, absence of diabetes mellitus, higher baseline pc-ASPECTSs, and mTICI score of 2b-3 were associated with better functional outcome in the EVT group.

Machine Learning-Based Identification of Target Groups for Thrombectomy in Acute Stroke

Whether endovascular thrombectomy (EVT) improves functional outcome in patients with large-vessel occlusion (LVO) stroke that do not comply with inclusion criteria of randomized controlled trials (RCTs) but that are considered for EVT in clinical practice is uncertain. We aimed to systematically identify patients with LVO stroke underrepresented in RCTs who might benefit from EVT. Following the premises that (i) patients without reperfusion after EVT represent a non-treated control group and (ii) the level of reperfusion affects outcome in patients with benefit from EVT but not in patients without treatment benefit, we systematically assessed the importance of reperfusion level on functional outcome prediction using machine learning in patients with LVO stroke treated with EVT in clinical practice (N = 5235, German-Stroke-Registry) and in patients treated with EVT or best medical management from RCTs (N = 1488, Virtual-International-Stroke-Trials-Archive). The importance of reperfusion level on outcome prediction in an RCT-like real-world cohort equaled the importance of EVT treatment allocation for outcome prediction in RCT data and was higher compared to an unselected real-world population. The importance of reperfusion level was magnified in patient groups underrepresented in RCTs, including patients with lower NIHSS scores (0-10), M2 occlusions, and lower ASPECTS (0-5 and 6-8). Reperfusion level was equally important in patients with vertebrobasilar as with anterior LVO stroke. The importance of reperfusion level for outcome prediction identifies patient target groups who likely benefit from EVT, including vertebrobasilar stroke patients and among patients underrepresented in RCT patients with low NIHSS scores, low ASPECTS, and M2 occlusions.

Thrombectomy of symptomatic isolated occlusions of posterior cerebral arteries in segment P1 and P2 in acute stroke treatment

BACKGROUND

Interventional stroke treatments for occlusions of the posterior circulation are established procedures. However, there are limited data on the treatment of isolated symptomatic P1 and P2 occlusions, which we have examined in this study.

PURPOSE

To investigate the mechanical thrombectomy of distal posterior occlusions.

MATERIAL AND METHODS

Retrospectively, data from patients with isolated P1 and P2 occlusions treated with MT were evaluated. Successful reperfusions have been defined as modified thrombolysis in cerebral infarct (mTICI) Grade 2b-3. A good clinical outcome was defined as a 90-day modified Rankin score 0-2.

RESULTS

All 79 treated patients were primarily aspirated. Stent retrievers were used secondarily in nine patients. Successful reperfusion was achieved in 95% of patients. Of the patients, 57% had a favorable clinical outcome after 90 days.

CONCLUSION

Mechanical thrombectomy with first line aspiration of symptomatic P1 and P2 occlusions is a safe and effective procedure.

Accuracy of CTA evaluations in daily clinical practice for large and medium vessel occlusion detection in suspected stroke patients

INTRODUCTION

Early detection of large vessel occlusion (LVO) is essential to facilitate fast endovascular treatment. CT angiography (CTA) is used to detect LVO in suspected stroke patients. We aimed to assess the accuracy of CTA evaluations in daily clinical practice in a large cohort of suspected stroke patients.

PATIENTS AND METHODS

We used data from the PRESTO study, a multicenter prospective observational cohort study that included suspected stroke patients between August 2018 and September 2019. Baseline CTAs were re-evaluated by an imaging core laboratory and compared to the local assessment. LVO was defined as an occlusion of the intracranial internal carotid artery, M1 segment, or basilar artery. Medium vessel occlusion (MeVO) was defined as an A1, A2, or M2 occlusion. We calculated the accuracy, sensitivity, and specificity to detect LVO and LVO+MeVO, using the core laboratory evaluation as reference standard.

RESULTS

We included 656 patients. The core laboratory detected 89 LVOs and 74 MeVOs in 155 patients. Local observers missed 6 LVOs (7%) and 28 MeVOs (38%), of which 23 M2 occlusions. Accuracy of LVO detection was 99% (95% CI: 98-100%), sensitivity 93% (95% CI: 86-97%), and specificity 100% (95% CI: 99-100%). Accuracy of LVO+MeVO detection was 95% (95% CI: 93-96%), sensitivity 79% (95% CI: 72-85%), and specificity 99% (95% CI: 98-100%).

DISCUSSION AND CONCLUSION

CTA evaluations in daily clinical practice are highly accurate and LVOs are adequately recognized. The detection of MeVOs seems more challenging. The evolving EVT possibilities emphasize the need to improve CTA evaluations in the acute setting.

Clinical protocol of the ischemic stroke patients treatment

Today in Ukraine there is no single standardized protocol for the treatment of patients in the acute period of ischemic stroke using modern methods of diagnosis and treatment, which include thrombolytic therapy and endovascular treatment. This protocol was created and implemented in Scientific-practical Center of endovascular neuroradiology, NAMS of Ukraine and is based on the latest recommendations of AHA/ASA and ESO, as well as registers of patients with ischemic stroke. The main purpose of this publication is the creation and implementation of «instructions» for the diagnosis and selection of objective tactics for treating patients in the acute period of ischemic stroke.

Endovascular treatment for acute Basilar Artery Occlusion - a multicenter randomized controlled trial (ATTENTION)

BACKGROUND AND HYPOTHESIS

Recently, two multicenter randomized controlled trials (RCT) failed to show a significantly beneficial effect of endovascular treatment (EVT) in patients with acute basilar artery occlusion (BAO). However, both trials suffered from equipoise issues which may have hindered the validity of the trial results. Therefore, additional RCT studies are needed to explore the potential benefit of EVT in patients presenting with BAO.

STUDY DESIGN

ATTENTION is an investigator-initiated, multicenter, prospective, randomized, controlled clinical trial with open-label treatment and blinded outcome assessment (PROBE) of EVT versus best medical management (BMM). The primary effect parameter is a modified Rankin Score of 0-3 at day 90.

DISCUSSION

ATTENTION will provide evidence for the efficacy and safety of EVT in stroke patients within 12 hours after BAO.

Sedation Mode During Endovascular Stroke Treatment in the Posterior Circulation-Is Conscious Sedation for Eligible Patients Feasible?

Background and Purpose: To compare safety and efficacy of conscious sedation (CS) vs. general anesthesia (GA) in endovascular stroke treatment (EST) of the posterior circulation (PC). Methods: Retrospective single-center analysis of patients receiving EST for large-vessel occlusion (LVO) in PC between January 2015 and November 2020. Exclusion criteria were severe stroke syndromes (NIHSS > 20), decreased level of consciousness, intubation for transport, and second stroke within 3 months of follow-up. The primary endpoint was a favorable clinical outcome 90 days after stroke onset (mRS 0-2 or 3 if pre-stroke mRS 3). Secondary endpoints were the rate of EST failure and procedural complications. Results: Of 111 included patients, 45/111 patients (40.5%) were treated under CS and 60/111 (54.0%) under GA. In 6/111 cases (5.4%), sedation mode was changed from CS to GA during EST. Patients treated under CS showed a lower mRS 90 days after stroke onset [mRS, median (IQR): 2.5 (1-4) CS vs. 3 (2-6) GA, p = 0.036] and a comparable rate of good outcome [good outcome, n (%): 19 (42.2) CS vs. 15 (32.6) GA, p = 0.311]. There was no difference in complication rates during EST (6.7% CS vs. 8.3% GA) or intracranial bleeding in follow-up imaging [n (%): 4 (8.9) CS vs. 7 (11.7) GA), p = 0.705]. The rate of successful target vessel recanalization did not differ (84.4% CS vs. 85.0 % GA). Conclusions: In this retrospective study, EST of the posterior circulation under conscious sedation was for eligible patients comparably safe and effective to patients treated under general anesthesia.

Endovascular Therapy for Stroke due to Basilar Artery Occlusion: A BASIC Challenge at BEST

Basilar artery occlusion stroke is known to have poor outcome with a high rate of morbidity and mortality despite best medical therapy. Since the original report of intra-arterial therapy for basilar artery occlusion in 1983, two recent randomized trials comparing endovascular therapy versus best medical management were completed on a large scale, BASICS (Basilar Artery International Cooperation Study) and the BEST trial (Basilar Artery Occlusion Endovascular Intervention Versus Standard Medical Treatment), both of which demonstrated equivocal benefit of the two modalities. In this commentary, we comment and highlight important lessons related to basilar occlusion stroke as learned from the BASICS and BEST randomized trials.

Automated Final Lesion Segmentation in Posterior Circulation Acute Ischemic Stroke Using Deep Learning

Final lesion volume (FLV) is a surrogate outcome measure in anterior circulation stroke (ACS). In posterior circulation stroke (PCS), this relation is plausibly understudied due to a lack of methods that automatically quantify FLV. The applicability of deep learning approaches to PCS is limited due to its lower incidence compared to ACS. We evaluated strategies to develop a convolutional neural network (CNN) for PCS lesion segmentation by using image data from both ACS and PCS patients. We included follow-up non-contrast computed tomography scans of 1018 patients with ACS and 107 patients with PCS. To assess whether an ACS lesion segmentation generalizes to PCS, a CNN was trained on ACS data (ACS-CNN). Second, to evaluate the performance of only including PCS patients, a CNN was trained on PCS data. Third, to evaluate the performance when combining the datasets, a CNN was trained on both datasets. Finally, to evaluate the performance of transfer learning, the ACS-CNN was fine-tuned using PCS patients. The transfer learning strategy outperformed the other strategies in volume agreement with an intra-class correlation of 0.88 (95% CI: 0.83-0.92) vs. 0.55 to 0.83 and a lesion detection rate of 87% vs. 41-77 for the other strategies. Hence, transfer learning improved the FLV quantification and detection rate of PCS lesions compared to the other strategies.

A Direct Aspiration First Pass Technique for Vertebra-Basilar Occlusion: A Retrospective Comparison to Stent Retriever

OBJECTIVES

This study aimed to assess the clinical usefulness of a direct aspiration first pass technique as a first-line strategy for mechanical thrombectomy in posterior circulation.

MATERIALS AND METHODS

We examined 34 consecutive patients treated with mechanical thrombectomy for acute vertebrobasilar artery occlusion. Procedural and clinical outcomes were assessed and compared between patients treated with a direct aspiration first pass technique first-line strategy (ADAPT group) and stent retriever system first-line strategy (stent retriever group).

RESULTS

Overall, successful reperfusion, complete reperfusion, and first-pass effects were achieved in 94.1%, 61.8%, and 50% of patients with acute ischemic stroke in vertebra-basilar artery occlusion treated with mechanical thrombectomy, respectively. The ADAPT group required a significantly shorter procedural time (p=.015) and fewer attempts (p=.0498) to achieve successful recanalization than the stent retriever group. The ADAPT group also tended to show better recanalization rates and first-pass effects than the stent retriever group. The rates of favorable outcomes seemed to be better, although insignificant, in the ADAPT group than in the stent retriever group (52.2% vs. 27.3%, p=.217). However, a significant correlation between the time required for reperfusion and clinical outcome was detected, and this will serve as the rationale for encouraging a direct aspiration first pass technique as a first-line strategy in the acute vertebra-basilar artery.

CONCLUSIONS

The a direct aspiration first pass technique first-line strategy for mechanical thrombectomy in posterior circulation may achieve successful recanalization with fewer attempts and shorter durations than the stent retriever first-line strategy.

EndoVAscular treatment and ThRombolysis for Ischemic Stroke Patients (EVA-TRISP) registry: basis and methodology of a pan-European prospective ischaemic stroke revascularisation treatment registry

PURPOSE

The Thrombolysis in Ischemic Stroke Patients (TRISP) collaboration was a concerted effort initiated in 2010 with the purpose to address relevant research questions about the effectiveness and safety of intravenous thrombolysis (IVT). The collaboration also aims to prospectively collect data on patients undergoing endovascular treatment (EVT) and hence the name of the collaboration was changed from TRISP to EVA-TRISP. The methodology of the former TRISP registry for patients treated with IVT has already been published. This paper focuses on describing the EVT part of the registry.

PARTICIPANTS

All centres committed to collecting predefined variables on consecutive patients prospectively. We aim for accuracy and completeness of the data and to adapt local databases to investigate novel research questions. Herein, we introduce the methodology of a recently constructed academic investigator-initiated open collaboration EVT registry built as an extension of an existing IVT registry in patients with acute ischaemic stroke (AIS).

FINDINGS TO DATE

Currently, the EVA-TRISP network includes 20 stroke centres with considerable expertise in EVT and maintenance of high-quality hospital-based registries. Following several successful randomised controlled trials (RCTs), many important clinical questions remain unanswered in the (EVT) field and some of them will unlikely be investigated in future RCTs. Prospective registries with high-quality data on EVT-treated patients may help answering some of these unanswered issues, especially on safety and efficacy of EVT in specific patient subgroups.

FUTURE PLANS

This collaborative effort aims at addressing clinically important questions on safety and efficacy of EVT in conditions not covered by RCTs. The TRISP registry generated substantial novel data supporting stroke physicians in their daily decision making considering IVT candidate patients. While providing observational data on EVT in daily clinical practice, our future findings may likewise be hypothesis generating for future research as well as for quality improvement (on EVT). The collaboration welcomes participation of further centres willing to fulfill the commitment and the outlined requirements.

Diagnostic and prognostic computed tomography imaging markers in basilar artery occlusion (Review)

Acute ischemic stroke treatment has been revolutionized by the addition of mechanical and aspiration thrombectomy. Randomized controlled trials have proven beyond doubt, the substantial clinical impact of endovascular interventions in anterior circulation territory strokes. Unfortunately, patients with vertebrobasilar ischemic stroke could not be included in these early trials due to inherent clinical, radiological, and prognostic particularities of posterior circulation ischemia; thus, indications for the treatment of posterior fossa strokes and basilar artery occlusion (BAO) are mainly based on retrospective studies and registries. BAO carries high morbidity and mortality, despite the new improvements in endovascular therapy. Identifying patients who will likely benefit from invasive treatment and have a good clinical outcome resides in discovering clinical, biological, or imaging markers, that have prognostic implications. Such imaging markers have been described, especially in the last decade. Hyperdense Basilar Artery Sign (HDBA), Posterior Circulations-Alberta Stroke Program Early CT Score (pc-ASPECTS), Pons-Midbrain Index (PMI), Posterior Circulation Collateral Score (pc-CS), Posterior Circulation CT Angiography Score (pc-CTA), and Basilar Artery on CT Prognostic Score (BATMAN), are computed tomography (CT) markers with properties that can aid the diagnosis of BAO and can independently predict clinical outcome. This paper aims to present a comprehensive review of these imaging signs to have a thorough understanding of their diagnostic and prognostic attributes.

Comparison of Risk Factors, Safety, and Efficacy Outcomes of Mechanical Thrombectomy in Posterior vs. Anterior Circulation Large Vessel Occlusion

Background and Purpose: It is believed that stroke occurring due to posterior circulation large vessel occlusion (PCLVO) and that occurring due to anterior circulation large vessel occlusion (ACLVO) differ in terms of their pathophysiology and the outcome of their acute management in relation to endovascular mechanical thrombectomy (MT). Limited sample size and few randomized controlled trials (RCTs) with respect to PCLVO make the safety and efficacy of MT, which has been confirmed in ACLVO, difficult to assess in the posterior circulation. We therefore conducted a meta-analysis to study to which extent MT in PCLVO differs from ACLVO. Materials and Methods: We searched the databases PubMed, Cochrane, and EMBASE for studies published between 2010 and January 2021, with information on risk factors, safety, and efficacy outcomes of MT in PCLVO vs. ACLVO and conducted a systematic review and meta-analysis; we compared baseline characteristics, reperfusion treatment profiles [including rates of intravenous thrombolysis (IVT) and onset-to-IVT and onset-to-groin puncture times], recanalization success [Thrombolysis In Cerebral Infarction scale (TICI) 2b/3], symptomatic intracranial hemorrhage (sICH), and favorable functional outcome [modified Rankin Score (mRS) 0-2] and mortality at 90 days. Results: Sixteen studies with MT PCLVO (1,172 patients) and ACLVO (7,726 patients) were obtained from the search. The pooled estimates showed higher baseline National Institutes of Health Stroke Scale (NIHSS) score (SMD 0.32, 95% CI 0.15-0.48) in the PCLVO group. PCLVO patients received less often IVT (OR 0.65, 95% CI 0.53-0.79). Onset-to-IVT time (SMD 0.86, 95% CI 0.45-1.26) and onset-to-groin puncture time (SMD 0.59, 95% CI 0.33-0.85) were longer in the PCLVO group. The likelihood of obtaining successful recanalization and favorable functional outcome at 90 days was comparable between the two groups. PCLVO was, however, associated with less sICH (OR 0.56, 95% CI 0.37-0.85) but higher mortality (OR 1.92, 95% CI 1.46-2.53). Conclusions: This meta-analysis indicates that MT in PCLVO may be comparably efficient in obtaining successful recanalization and 90 day favorable functional outcome just as in ACLVO. Less sICH in MT-treated PCLVO patients might be the result of the lower IVT rate in this group. Higher baseline NIHSS and longer onset-to-IVT and onset-to-groin puncture times may have contributed to a higher 90 day mortality in PCLVO patients.

Diagnostic and prognostic utility of computed tomography perfusion imaging in posterior circulation acute ischemic stroke: A systematic review and meta-analysis

BACKGROUND

Computed tomography perfusion (CTP) imaging could be useful in the diagnosis of posterior circulation stroke (PCS) and in identifying patients who are likely to experience favorable outcomes following reperfusion therapy. The current study sought to investigate the diagnostic and prognostic capability of CTP in acute ischemic PCS by performing a systematic review and meta-analysis.

METHODS

Medline/PubMed and the Cochrane Library were searched using the terms: "posterior circulation", "CT perfusion", "acute stroke", and "reperfusion therapy". The following studies were included: (1) patients aged 18 years or above; (2) patients diagnosed with PCS; and (3) studies with good methodological design. Pooled sensitivity (SENS), specificity (SPEC), and area under the curve (AUC), computed using the summary receiver operating characteristic (SROC) curves, were used to determine diagnostic/prognostic capability.

RESULTS

Out of 14 studies included, a meta-analysis investigating diagnostic accuracy of CTP was performed on nine studies. Meta-analysis demonstrated comparable diagnostic accuracy of CTP to non-contrast computed tomography (NCCT) (AUC_CTP : 0.90 [95% CI 0.87-0.92] vs. AUC_NCCT : 0.96 [95% CI 0.94-0.97]); however, with higher pooled sensitivity (SENS_CTP : 72% [95% CI 57%-83%] vs. SENS_NCCT : 25% [95% CI 17%-35%]) and lower specificity (SPEC_CTP : 90% [95% CI 83%-94%] vs. SPEC_NCCT : 96% [95% CI 95%-98%]) than NCCT. Meta-analysis to determine prognostic capability of CTP could not be performed.

CONCLUSIONS

CTP has limited diagnostic utility in acute ischemic PCS, albeit with superior diagnostic sensitivity and inferior diagnostic specificity to NCCT. Further prospective trials are required to validate the prognostic capability of CTP-derived parameters in PCS.

Endovascular Therapy for Stroke Due to Basilar-Artery Occlusion

BACKGROUND

The effectiveness of endovascular therapy in patients with stroke caused by basilar-artery occlusion has not been well studied.

METHODS

We randomly assigned patients within 6 hours after the estimated time of onset of a stroke due to basilar-artery occlusion, in a 1:1 ratio, to receive endovascular therapy or standard medical care. The primary outcome was a favorable functional outcome, defined as a score of 0 to 3 on the modified Rankin scale (range, 0 to 6, with 0 indicating no disability, 3 indicating moderate disability, and 6 indicating death) at 90 days. The primary safety outcomes were symptomatic intracranial hemorrhage within 3 days after the initiation of treatment and mortality at 90 days.

RESULTS

A total of 300 patients were enrolled (154 in the endovascular therapy group and 146 in the medical care group). Intravenous thrombolysis was used in 78.6% of the patients in the endovascular group and in 79.5% of those in the medical group. Endovascular treatment was initiated at a median of 4.4 hours after stroke onset. A favorable functional outcome occurred in 68 of 154 patients (44.2%) in the endovascular group and 55 of 146 patients (37.7%) in the medical care group (risk ratio, 1.18; 95% confidence interval [CI], 0.92 to 1.50). Symptomatic intracranial hemorrhage occurred in 4.5% of the patients after endovascular therapy and in 0.7% of those after medical therapy (risk ratio, 6.9; 95% CI, 0.9 to 53.0); mortality at 90 days was 38.3% and 43.2%, respectively (risk ratio, 0.87; 95% CI, 0.68 to 1.12).

CONCLUSIONS

Among patients with stroke from basilar-artery occlusion, endovascular therapy and medical therapy did not differ significantly with respect to a favorable functional outcome, but, as reflected by the wide confidence interval for the primary outcome, the results of this trial may not exclude a substantial benefit of endovascular therapy. Larger trials are needed to determine the efficacy and safety of endovascular therapy for basilar-artery occlusion. (Funded by the Dutch Heart Foundation and others; BASICS ClinicalTrials.gov number, NCT01717755; Netherlands Trial Register number, NL2500.).

A Pre-Interventional Scale to Predict in situ Atherosclerotic Thrombosis in Acute Vertebrobasilar Artery Occlusion Patients

Background and Purpose: Determining the occlusion mechanism before endovascular treatment (EVT) is of great significance for acute large vessel occlusion patients. We aimed to develop and validate a simple pre-EVT scale with readily available variables for predicting in situ atherosclerotic thrombosis (ISAT) in acute vertebrobasilar artery occlusion (VBAO) patients.

Materials and Methods: Consecutive patients were retrieved from Nanjing Stroke Registry Program between January 2014 and December 2019 as a derivation cohort. Anonymous data of consecutive patients between January 2014 and December 2019 were collected from another comprehensive stroke center as an external validation cohort. Demographics, medical histories, and clinical characteristics were collected. ISAT was defined according to the following criteria: (a) detection of moderate to severe (≥50%) stenosis or stenosis with significant distal flow impairment at the occluded segment when successful reperfusion was achieved; (b) transient visualization of eccentric plaque contour or a recurrent re-occlusion tendency when reperfusion was unsuccessful. Logistic regression was taken to develop a predictive scale. The performance of the scale was assessed by area under the receiver operating characteristic curve (AUC) and Hosmer–Lemeshow test.

Results: ISAT was observed in 41 of 95 (43.2%) patients included in the derivation cohort. The ISAT predictive scale consisted of three pre-interventional predictors, including the history of hypertension, atrial fibrillation rhythm, and baseline serum glucose level ≥7.55 mmol/L. The model depicted acceptable calibration (Hosmer–Lemeshow test, P = 0.554) and good discrimination (AUC, 0.853; 95% confidence interval, 0.775–0.930). The optimal cutoff value of the ISAT scale was 1 point with 95.1% sensitivity, 64.8% specificity, and 77.9% accuracy. In the validation cohort, the discrimination ability was still promising with an AUC value of 0.800 (0.682–0.918).

Conclusion: The three-item scale comprised of the history of hypertension, atrial fibrillation rhythm, and dichotomous serum glucose level had a promising predictive value for ISAT before EVT in acute VBAO patients.

Joint European and World Stroke Organisation (ESO-WSO) conference highlights-2020

Despite a difficult year focusing on the COVID-19 pandemic, from 7 November to 8 November, stroke clinicians and researchers experienced a great opportunity to learn about the latest research results and developments across the entire care spectrum. This year’s European and World Stroke Organisation Conference was not only the first joint conference but also the first virtual experience of this magnitude in the field. More than 5000 participants were registered worldwide. Many interesting studies and impactful large trial results were presented giving rise to lively controversies (live sessions and chats). This article will focus on a few selected studies that were presented at the conference, ranging from insights into pre-hospital triage, acute interventions, to secondary prevention, rehabilitation and the impact of the current pandemic on stroke care.

Thrombectomy for Comatose Patients with Basilar Artery Occlusion : A Multicenter Study

PURPOSE

Acute ischemic stroke (AIS) secondary to a basilar artery occlusion (BAO) carries a poor prognosis, especially in cases of severe symptoms, such as coma at presentation. Despite a lack of evidence, mechanical thrombectomy (MT) is often performed as the procedural risks are felt to be minimal compared to the natural history. We sought to evaluate MT efficacy and safety in comatose BAO patients.

METHODS

We performed a retrospective analysis of a multicenter prospective cohort of consecutive AIS patients with BAO who underwent MT. We compared baseline characteristics between comatose and noncomatose BAO patients, as well as clinical outcomes (modified Rankin scale, mRS 0-3 at 3 months). Using a multivariate logistic regression, we examined the population of comatose patients for baseline predictive factors of mortality.

RESULTS

We included 269 patients, 72 (27%) comatose and 197 (73%) non-comatose. Despite similar recanalization rates between comatose and non-comatose patients (83% vs. 90% p = 0.221), comatose patient long-term outcomes were dramatically worse (11% mRS 0-3 vs. 54%, p < 0.0001) and mortality was higher (64% vs. 34%, p < 0.0001). Baseline predictors of mortality at 3 months among comatose BAO patients after multivariate analysis were the following: male sex (odds ratio, OR 31.20, 2.57-378.52, p = 0.007), older age (OR 1.13, 1.04-1.24, p = 0.007) and higher serum glucose levels (OR 1.54, 1.07-2.21, p = 0.019).

CONCLUSION

Thrombectomy is technically effective for BAO patients presenting with coma; however, the long-term favorable outcome remains poor. Male sex, old age and hyperglycemia were predictors of mortality in these patients.

Posterior Circulation Endovascular Thrombectomy for Large-Vessel Occlusion: Predictors of Favorable Clinical Outcome and Analysis of First-Pass Effect

BACKGROUND AND PURPOSE

Successful vessel recanalization in posterior circulation large-vessel occlusion is considered crucial, though the evidence of clinical usefulness, compared with the anterior circulation, is not still determined. The aim of this study was to evaluate predictors of favorable clinical outcome and to analyze the effect of first-pass thrombectomy.

MATERIALS AND METHODS

A retrospective, multicenter, observational study was conducted in 10 high-volume stroke centers in Europe, including the period from January 2016 to July 2019. Only patients with an acute basilar artery occlusion or a single, dominant vertebral artery occlusion ("functional" basilar artery occlusion) who had a 3-month mRS were included. Clinical, procedural, and radiologic data were evaluated, and the association between these parameters and both the functional outcome and the first-pass effect was assessed.

RESULTS

A total of 191 patients were included. A lower baseline NIHSS score (adjusted OR, 0.77; 95% CI, 0.61-0.96; P = .025) and higher baseline MR imaging posterior circulation ASPECTS (adjusted OR, 3.01; 95% CI, 1.03-8.76; P = .043) were predictors of better outcomes. The use of large-bore catheters (adjusted OR, 2.25; 95% CI, 1.08-4.67; P = .030) was a positive predictor of successful reperfusion at first-pass, while the use of a combined technique was a negative predictor (adjusted OR, 0.26; 95% CI, 0.09-0.76; P = .014).

CONCLUSIONS

The analysis of our retrospective series demonstrates that a lower baseline NIHSS score and a higher MR imaging posterior circulation ASPECTS were predictors of good clinical outcome. The use of large-bore catheters was a positive predictor of first-pass modified TICI 2b/3; the use of a combined technique was a negative predictor.

Assessment of Endovascular Treatment for Acute Basilar Artery Occlusion via a Nationwide Prospective Registry

Importance

Several randomized clinical trials have recently established the safety and efficacy of endovascular treatment (EVT) of acute ischemic stroke in the anterior circulation. However, it remains uncertain whether patients with acute basilar artery occlusion (BAO) benefit from EVT.

Objective

To evaluate the association between EVT and clinical outcomes of patients with acute BAO.

Design, Setting, and Participants

This nonrandomized cohort study, the EVT for Acute Basilar Artery Occlusion Study (BASILAR) study, was a nationwide prospective registry of consecutive patients presenting with an acute, symptomatic, radiologically confirmed BAO to 47 comprehensive stroke centers across 15 provinces in China between January 2014 and May 2019. Patients with acute BAO within 24 hours of estimated occlusion time were divided into groups receiving standard medical treatment plus EVT or standard medical treatment alone.

Main Outcomes and Measures

The primary outcome was the improvement in modified Rankin Scale scores (range, 0 to 6 points, with higher scores indicating greater disability) at 90 days across the 2 groups assessed as a common odds ratio using ordinal logistic regression shift analysis, adjusted for prespecified prognostic factors. The secondary efficacy outcome was the rate of favorable functional outcomes defined as modified Rankin Scale scores of 3 or less (indicating an ability to walk unassisted) at 90 days. Safety outcomes included symptomatic intracerebral hemorrhage and 90-day mortality.

Results

A total of 1254 patients were assessed, and 829 patients (of whom 612 were men [73.8%]; median [interquartile] age, 65 [57-74] years) were recruited into the study. Of these, 647 were treated with standard medical treatment plus EVT and 182 with standard medical treatment alone. Ninety-day functional outcomes were substantially improved by EVT (adjusted common odds ratio, 3.08 [95% CI, 2.09-4.55]; P < .001). Moreover, EVT was associated with a significantly higher rate of 90-day modified Rankin Scale scores of 3 or less (adjusted odds ratio, 4.70 [95% CI, 2.53-8.75]; P < .001) and a lower rate of 90-day mortality (adjusted odds ratio, 2.93 [95% CI, 1.95-4.40]; P < .001) despite an increase in symptomatic intracerebral hemorrhage (45 of 636 patients [7.1%] vs 1 of 182 patients [0.5%]; P < .001).

Conclusions and Relevance

Among patients with acute BAO, EVT administered within 24 hours of estimated occlusion time is associated with better functional outcomes and reduced mortality.

Intervention for symptomatic vertebrobasilar disease

Disease of the vertebral (VA) and basilar arteries (BA) can lead to stroke of the posterior circulation and may warrant management strategies which differ from the anterior circulation. The mechanism and location of the disease determine its natural history and therefore affect the relative risks and benefits of the possible treatment options. Vertebrobasilar (VB) atherosclerotic disease is a source of both hemodynamic and embolic posterior circulation stroke. Advances in medical therapy have decreased the rate of stroke after initial symptomatic presentation. Antiplatelet therapy, blood pressure control, and optimization of secondary risk factors can reduce recurrent stroke risk in both intracranial and extracranial VB disease. However, symptomatic intracranial disease is still associated with a high risk of subsequent stroke, particularly those with hemodynamic compromise who represent a higher risk population. Patients with hemodynamic impairment may benefit from judicious application of endovascular and microsurgical interventions to augment blood flow. Stenting, angioplasty alone, bypass surgery, and endarterectomy, represent endovascular and surgical tools available to address medically refractory VB disease. Apart from atherosclerotic disease, dissection is another etiology of VB stroke, most frequently affecting the extracranial VA. Treatment is predominantly antithrombotic therapy although surgical or endovascular intervention can be required in rare cases of persistent embolism or hemodynamic compromise. In contrast, extrinsic compromise of the VA represents a separate extracranial pathology and is best treated with mechanistically targeted surgeries or extracranial bypass.

Basilar Artery Occlusion and Emerging Treatments

Basilar artery occlusion is a relatively uncommon but neurologically devastating condition. If revascularization is not achieved, the potential for death and disability is substantial. During the last several years, there have been positive endovascular stroke trials for the treatment of large vessel occlusion; however, all of them excluded patients with basilar artery occlusion. The current treatment of basilar artery occlusion is still founded on small observational studies or meta-analyses. As case selection for revascularization and treatment protocols often vary widely across institutions, sample sizes remain limited. In this article, we aim to review some of the larger observational studies in stroke due to basilar artery occlusion, considering potential treatment strategies and resultant outcomes.

Predictors of favorable outcomes for vertebrobasilar artery occlusion after endovascular therapy within 24 hours of symptom onset

OBJECTIVE

The aim of the present study was to describe our results of endovascular therapy (EVT) for vertebrobasilar artery occlusion (VBAO) within 24 h of symptom onset, and to evaluate prognostic factors associated with favorable outcomes.

METHODS

The present study enrolled patients who underwent EVT for acute ischemic stroke (AIS) caused by VBAO. Inclusion criteria for EVT to treat VBAO were as follows: (1) computed tomography angiography (CTA) or magnetic resonance angiography (MRA) confirmed acute VBAO; (2) baseline National Institutes of Health Stroke Scale (NIHSS) score ≥2; (3) premorbid modified Rankin scale (mRS) score ≤2; (4) onset or last known time to puncture within 24 h; and (5) posterior-circulation Acute Stroke Prognosis Early CT score (pc-ASPECTS) ≥6. Favorable outcomes were defined as mRS scores of 0-3 at three months following EVT. The associations among baseline parameters, procedural parameters, and favorable outcomes were assessed.

RESULTS

A total of 67 patients were recruited in this study, of which 40 patients (59.7 %) had favorable outcomes. Of the 50 patients with a late-window (6-24 h), 29 patients (58 %) had favorable outcomes. Univariate analysis revealed significant associations of the following parameters with favorable outcomes in the enrolled patients: age, sex, smoking status, baseline NIHSS score, baseline Glasgow coma scale (GCS) score, Pons-midbrain index (PMI), and intracranial atherosclerosis (ICAS). Multivariate logistic regression indicated that only age (OR 0.914, 95 % CI: 0.849 to 0.984; p = 0.017), baseline GCS score (OR 1.234, 95 % CI: 1.061-1.435; p = 0.006), and PMI (OR 0.448, 95 % CI: 0.252 to 0.798; p = 0.006) were independently associated with favorable outcomes at three months following EVT. After adjustments for confounding factors in patients with a late-window, only age (OR 0.879, 95 % CI: 0.799 to 0.967; p = 0.008) was associated with favorable outcomes.

CONCLUSIONS

Younger age, lower PMI, and higher GCS scores in patients with VBAO-induced AIS were associated with more favorable outcomes. In late-window (6-24 h) patients, younger age associated to favorable outcomes, and lower NIHSS scores and lower PMI each also had a tendency to associated with favorable outcomes.

Acute ischemic stroke management: concepts and controversies.A narrative review

INTRODUCTION

Amongst the 25.7 million survivors and 6.5 million deaths from stroke between 1990 and 2013, ischemic strokes accounted for approximately 70% and 50% of the cases, respectively. With patients still suffering from complications and stroke recurrence, more questions have been raised as to how we can better improve patient management.

AREAS COVERED

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement and Newcastle-Ottawa Scale (NOS) were adopted to ensure a comprehensive inclusion of quality literature from various sources. PubMed and Embase were searched for evidence on thrombolysis, mechanical thrombectomy, artificial intelligence (AI), antiplatelet therapy, anticoagulation and hypertension management.

EXPERT OPINION

The directions of future research in these areas are dependent on the current level of validation. Endovascular therapy and applications of AI are relatively new compared to the other areas discussed in this review. As such, future studies need to focus on validating their efficacy. As for thrombolysis, antiplatelet and anticoagulation therapy, their efficacy has been well-established and future research efforts should be directed toward adjusting its use according to patient-specific factors, starting with factors with the most clinical relevance and prevalence.

Rapid Successful Reperfusion of Basilar Artery Occlusion Strokes With Pretreatment Diffusion-Weighted Imaging Posterior-Circulation ASPECTS <8 Is Associated With Good Outcome

Background

The association between time to reperfusion and clinical outcome is well known in anterior circulation strokes, whereas the impact of main time metrics remains unknown in posterior circulation strokes. We investigated the clinical effect of different time intervals from symptom onset to reperfusion on the 90‐day clinical outcome in acute ischemic stroke patients with basilar artery occlusion, and especially in the subset population presenting a low stroke volume on baseline diffusion‐weighted imaging.

Methods and Results

We studied patients included in the prospective, multicenter, observational ETIS (Endovascular Treatment in Ischemic Stroke) registry who had had basal artery occlusion and had achieved successful reperfusion (modified Thrombolysis In Cerebral Infarction 2b‐3). Three time intervals (onset to reperfusion, onset to imaging, and imaging to reperfusion) were considered in all patients and separately in patients with pc‐ASPECTS (posterior‐circulation Alberta Stroke Program Early Computed Tomography Score) <8 and ≥8 on baseline diffusion‐weighted imaging. The primary end point was good outcome defined as 90‐day modified Rankin Scale scores of 0 to 2. Among the 95 included patients, 38 (40%) achieved a good outcome. In all patients, no significant association was found between the different time intervals and outcome. In patients evaluated with diffusion‐weighted imaging (n=61) at baseline, a significant negative association was found between imaging‐to‐reperfusion time for patients with pc‐ASPECTS <8 (adjusted odds ratio=0.4 per 30‐minute increase; 95% CI 0.18‐0.85; P=0.02) compared with those with pc‐ASPECTS ≥8.

Conclusions

In patients with basilar artery occlusion and pc‐ASPECTS <8 at baseline diffusion‐weighted imaging, clinical outcome is highly dependent on the time from imaging to reperfusion, which suggests that rapid endovascular reperfusion should be performed after imaging in these patients.

Predictors of Favorable Outcome after Endovascular Thrombectomy in MRI: Selected Patients with Acute Basilar Artery Occlusion

BACKGROUND AND PURPOSE

Clinical outcomes after endovascular treatment for acute basilar artery occlusions need further investigation. Our aim was to analyze predictors of a 90-day good functional outcome defined as mRS 0-2 after endovascular treatment in MR imaging-selected patients with acute basilar artery occlusions.

MATERIALS AND METHODS

We analyzed consecutive MR imaging-selected patients with acute basilar artery occlusions endovascularly treated within the first 24 hours after symptom onset. Successful and complete reperfusion was defined as modified TICI scores 2b-3 and 3, respectively. Outcome at 90 days was analyzed in univariate and multivariate analysis regarding baseline patient treatment characteristics and periprocedural outcomes.

RESULTS

One hundred ten patients were included. In 10 patients, endovascular treatment was aborted for failed proximal/distal access. Overall, successful reperfusion was achieved in 81.8% of cases (n = 90; 95% CI, 73.3%-88.6%). At 90 days, favorable outcome was 31.8%, with a mortality rate of 40.9%; the prevalence of symptomatic intracranial hemorrhage within 24 hours was 2.7%. The median time from symptom onset to groin puncture was 410 minutes (interquartile range, 280-540 minutes). In multivariable analysis, complete reperfusion (OR = 6.59; 95% CI, 2.17-20.03), lower pretreatment NIHSS (OR = 0.77; 95% CI, 0.64-0.94), the presence of posterior communicating artery collateral flow (OR = 2.87; 95% CI, 1.05-7.84), the absence of atrial fibrillation (OR = 0.18; 95% CI, 0.03-0.99), and intravenous thrombolysis administration (OR = 2.75; 95% CI, 1.04-7.04) were associated with 90-day favorable outcome.

CONCLUSIONS

In our series of MR imaging-selected patients with acute basilar artery occlusions, complete reperfusion was the strongest predictor of a good outcome. Lower pretreatment NIHSS, the presence of posterior communicating artery collateral flow, the absence of atrial fibrillation, and intravenous thrombolysis administration were associated with favorable outcome.

Diagnosis and management of acute ischaemic stroke

Acute ischaemic stroke is a major public health priority and will become increasingly relevant to neurologists of the future. The cornerstone of effective stroke care continues to be timely reperfusion treatment. This requires early recognition of symptoms by the public and first responders, triage to an appropriate stroke centre and efficient assessment and investigation by the attending stroke team. The aim of treatment is to achieve recanalisation and reperfusion of the ischaemic penumbra with intravenous thrombolysis and/or endovascular thrombectomy in appropriately selected patients. All patients should be admitted directly to an acute stroke unit for close monitoring for early neurological deterioration and prevention of secondary complications. Prompt investigation of the mechanism of stroke allows patients to start appropriate secondary preventative treatment. Future objectives include improving accessibility to endovascular thrombectomy, using advanced imaging to extend therapeutic windows and developing neuroprotective agents to prevent secondary neuronal damage.

Effects of Periprocedural Tirofiban vs. Oral Antiplatelet Drug Therapy on Posterior Circulation Infarction in Patients With Acute Intracranial Atherosclerosis-Related Vertebrobasilar Artery Occlusion

Background and purpose: Tirofiban and oral antiplatelet drugs can be used to inhibit reocclusion and restore microvascular reperfusion during endovascular treatment (EVT). This study compared recanalization rates, symptomatic intracranial hemorrhage (SICH), 90 day mortality, and functional outcomes between periprocedural tirofiban and antiplatelet therapy in patients with acute intracranial atherosclerosis-related vertebrobasilar artery occlusion.

Methods: A total of 105 consecutive patients with acute intracranial atherosclerosis-related vertebrobasilar artery occlusion who underwent EVT + tirofiban + oral antiplatelet or EVT + oral antiplatelet therapy at the Beijing Tiantan Hospital between January 2012 and July 2018 were included. Baseline characteristics, procedural parameters, and functional outcomes were assessed.

Results: Among the 105 patients, 74 underwent EVT + tirofiban + oral antiplatelet therapy, while 31 underwent EVT + oral antiplatelet drug therapy. EVT + tirofiban + oral antiplatelet therapy resulted in higher recanalization rates compared to EVT + oral antiplatelet drug therapy (93.24% vs. 77.42%; p = 0.038), whereas the risk for SICH, 90 day mortality, and functional independence outcomes did not differ between the groups. Logistic regression analysis revealed that EVT + tirofiban + oral antiplatelet therapy had an increased probability of higher recanalization rates (OR 0.18 [95% confidence interval (CI) 1.24–24.39]; p = 0.025). There were no differences in SICH (OR 0.00 [95% CI 0.00–Inf]; p = 0.998), 90 day mortality (OR 1.19 [95% CI 0.17–4.05]; p = 0.826), or functional independence (modified Rankin score 0 to ≤ 2) (OR 1.43 [95% CI 0.23–2.17]; p = 0.538) between the groups.

Conclusions: Ninety day functional outcomes of EVT + tirofiban + oral antiplatelet therapy were not superior to those of EVT + oral antiplatelet drug therapy; however, the recanalization rate was higher and the risks for SICH and 90 day mortality were lower.

Safety of inter-hospital transfer of patients with acute ischemic stroke for evaluation of endovascular thrombectomy

Stroke networks facilitate access to endovascular treatment (EVT) for patients with ischemic stroke due to large vessel occlusion. In this study we aimed to determine the safety of inter-hospital transfer and included all patients with acute ischemic stroke who were transferred within our stroke network for evaluation of EVT between 06/2016 and 12/2018. Data were derived from our prospective EVT database and transfer protocols. We analyzed major complications and medical interventions associated with inter-hospital transfer. Among 615 transferred patients, 377 patients (61.3%) were transferred within our telestroke network and had transfer protocols available (median age 76 years [interquartile range, IQR 17], 190 [50.4%] male, median baseline NIHSS score 17 [IQR 8], 246 [65.3%] drip-and-ship i.v.-thrombolysis). No patient suffered from cardio-respiratory failure or required emergency intubation or cardiopulmonary resuscitation during the transfer. Among 343 patients who were not intubated prior departure, 35 patients (10.2%) required medical interventions during the transfer. The performance of medical interventions was associated with a lower EVT rate and higher mortality at three months. In conclusion, the transfer of acute stroke patients for evaluation of EVT was not associated with major complications and transfer-related medical interventions were required in a minority of patients.

Outcomes of Endovascular Thrombectomy for Basilar Artery Occlusion

Background and Purpose:

Large prospective observational studies have cast doubt on the common assumption that endovascular thrombectomy (EVT) is superior to intravenous thrombolysis for patients with acute basilar artery occlusion (BAO). The purpose of this study was to retrospectively review our experience for patients with BAO undergoing EVT with modern endovascular devices.

Methods:

All consecutive patients undergoing EVT with either a second-generation stent retriever or direct aspiration thrombectomy for BAO at our regional stroke center from January 1, 2013 to March 1, 2019 were included. The primary outcome measure was functional outcome at 1 month using the modified Rankin Scale (mRS) score. Multivariable logistic regression was used to assess the association between patient characteristics and dichotomized mRS.

Results:

A total of 43 consecutive patients underwent EVT for BAO. The average age was 67 years with 61% male patients. Overall, 37% (16/43) of patients achieved good functional outcome. Successful reperfusion was achieved in 72% (31/43) of cases. The median (interquartile range) stroke onset to treatment time was 420 (270–639) minutes (7 hours) for all patients. The procedure-related complication rate was 9% (4/43). On multivariate analysis, posterior circulation Alberta stroke program early computed tomography score and Basilar Artery on Computed Tomography Angiography score were associated with improved functional outcome.

Conclusion:

EVT appears to be safe and feasible in patients with BAO. Our finding that time to treatment and successful reperfusion were not associated with improved outcome is likely due to including patients with established infarcts. Given the variability of collaterals in the posterior circulation, the paradigm of utilizing a tissue window may assist in patient selection for EVT. Magnetic resonance imaging may be a reasonable option to determine the extent of ischemia in certain situations.

Do thrombolysis outcomes differ between anterior circulation stroke and posterior circulation stroke? A systematic review and meta-analysis

BACKGROUND

It remains unclear whether thrombolysis outcomes can be influenced by the affected vascular territory (i.e. anterior circulation stroke vs. posterior circulation stroke) in stroke patients owing to the lack of randomized controlled trials.

AIMS

Using multiple comprehensive databases, we searched for observational studies of the safety and efficacy of intravenous thrombolytics and intra-arterial treatment with or without intravenous thrombolytics in accordance with the affected vascular territory. We performed a systematic review and meta-analysis. We evaluated symptomatic intracerebral hemorrhage, all-type intracerebral hemorrhage, mortality, and functional outcomes at three months. The recanalization rate was assessed in the intra-arterial treatment group.

SUMMARY OF REVIEW

Twenty-one studies including a report from our own stroke registry were included through quantitative synthesis. Compared with the anterior circulation stroke group, the posterior circulation stroke group had a lower risk of ICH, including symptomatic intracerebral hemorrhage and all-type intracerebral hemorrhage, after intravenous thrombolytics and tended to have favorable functional outcomes at three months. Mortality was similar between the two groups. Regarding intra-arterial treatment, the symptomatic intracerebral hemorrhage and post-procedural recanalization rates were comparable between the two groups, although the posterior circulation stroke group had a higher mortality risk and lower tendency for a favorable functional outcome.

CONCLUSIONS

Safety and efficacy of thrombolysis in posterior circulation stroke depends on involvement of large vessel occlusion and reperfusion modality such that intravenous thrombolytics is more effective and safer than in anterior circulation stroke; the safety and efficacy of intra-arterial treatment is comparable or lower than anterior circulation stroke. Considering the limitations of our meta-analysis, further studies are needed to provide high level evidence of a beneficial effect of intra-arterial treatment, and to identify patients' profiles associated with benefit of treatment.

Endovascular treatment versus standard medical treatment for vertebrobasilar artery occlusion (BEST): an open-label, randomised controlled trial

BACKGROUND

Previous randomised trials have shown an overwhelming benefit of mechanical thrombectomy for treating patients with stroke caused by large vessel occlusion of the anterior circulation. Whether endovascular treatment is beneficial for vertebrobasilar artery occlusion remains unknown. In this study, we aimed to investigate the safety and efficacy of endovascular treatment of acute strokes due to vertebrobasilar artery occlusion.

METHODS

We did a multicentre, randomised, open-label trial, with blinded outcome assessment of thrombectomy in patients presenting within 8 h of vertebrobasilar occlusion at 28 centres in China. Patients were randomly assigned (1:1) to endovascular therapy plus standard medical therapy (intervention group) or standard medical therapy alone (control group). The randomisation sequence was computer-generated and stratified by participating centres. Allocation concealment was implemented by use of sealed envelopes. The primary outcome was a modified Rankin scale (mRS) score of 3 or lower (indicating ability to walk unassisted) at 90 days, assessed on an intention-to-treat basis. The primary safety outcome was mortality at 90 days. Secondary safety endpoints included the rates of symptomatic intracranial haemorrhage, device-related complications, and other severe adverse events. The BEST trial is registered with ClinicalTrials.gov, NCT02441556.

FINDINGS

Between April 27, 2015, and Sept 27, 2017, we assessed 288 patients for eligibility. The trial was terminated early after 131 patients had been randomly assigned (66 patients to the intervention group and 65 to the control group) because of high crossover rate and poor recruitment. In the intention-to-treat analysis, there was no evidence of a difference in the proportion of participants with mRS 0-3 at 90 days according to treatment (28 [42%] of 66 patients in the intervention group vs 21 [32%] of 65 in the control group; adjusted odds ratio [OR] 1·74, 95% CI 0·81-3·74). Secondary prespecified analyses of the primary outcome, done to assess the effect of crossovers, showed higher rates of mRS 0-3 at 90 days in patients who actually received the intervention compared with those who received standard medical therapy alone in both per-protocol (28 [44%] of 63 patients with intervention vs 13 [25%] of 51 with standard therapy; adjusted OR 2·90, 95% CI 1·20-7·03) and as-treated (36 [47%] of 77 patients with intervention vs 13 [24%] of 54 with standard therapy; 3·02, 1·31-7·00) populations. The 90-day mortality was similar between groups (22 [33%] of 66 patients in the intervention vs 25 [38%] of 65 in the control group; p=0·54) despite a numerically higher prevalence of symptomatic intracranial haemorrhage in the intervention group.

INTERPRETATION

There was no evidence of a difference in favourable outcomes of patients receiving endovascular therapy compared with those receiving standard medical therapy alone. Results might have been confounded by loss of equipoise over the course of the trial, resulting in poor adherence to the assigned study treatment and a reduced sample size due to the early termination of the study.

FUNDING

Jiangsu Provincial Special Program of Medical Science.

Anesthetic Management of Emergency Endovascular Thrombectomy for Acute Ischemic Stroke, Part 1: Patient Characteristics, Determinants of Effectiveness, and Effect of Blood Pressure on Outcome

In the United States, stroke ranks fifth among all causes of death and is the leading cause of serious long-term disability. The 2018 American Heart Association stroke care guidelines consider endovascular thrombectomy to be the standard of care for patients who have acute ischemic stroke in the anterior circulation when arterial puncture can be made within 6 hours of symptom onset or within 6-24 hours of symptom onset when specific eligibility criteria are satisfied. The aim of this 2-part review is to provide practical perspective on the clinical literature regarding anesthesia care of patients treated with endovascular thrombectomy. Part 1 (this article) reviews the development of endovascular thrombectomy and the determinants of endovascular thrombectomy effectiveness irrespective of method of anesthesia. The first aim of part 1 is to explain why rapid workflow and maintenance of blood pressure are necessary to help support the ischemic brain until, as a result of endovascular thrombectomy, reperfusion is accomplished. The second aim of part 1, understanding the nonanesthesia factors determining endovascular thrombectomy effectiveness, is necessary to identify numerous biases present in observational reports regarding anesthesia for endovascular thrombectomy. With this background, in part 2 (the companion to this article), the observational literature is briefly summarized, largely to identify its weaknesses, but also to develop hypotheses derived from it that have been recently tested in 3 randomized clinical trials of sedation versus general anesthesia for endovascular thrombectomy. In part 2, these 3 trials are reviewed both from a functional outcomes perspective (meta-analysis) and a methodological perspective, providing specifics regarding anesthesia and hemodynamic management. Part 2 concludes with a pragmatic approach to anesthesia decision making (sedation versus general anesthesia) and acute phase anesthesia management of patients treated with endovascular thrombectomy.