Endovascular thrombectomy with versus without intravenous thrombolysis in patients with acute basilar artery occlusion: a systematic review and meta-analysis

BACKGROUND AND PURPOSE

The benefit and safety of intravenous thrombolysis before endovascular thrombectomy in patients with acute ischemic stroke caused by basilar artery occlusion (BAO) remains unclear. This article aims to investigate the clinical outcomes and safety of endovascular thrombectomy with versus without intravenous thrombolysis in acute BAO stroke patients.

METHODS

We conducted a comprehensive search of PubMed, Embase, Cochrane, and Web of Science databases to identify relevant literature pertaining to patients with acute BAO who underwent endovascular thrombectomy alone or intravenous thrombolysis bridging with endovascular thrombectomy (bridging therapy), until January 10, 2024. The primary outcome was functional independence, defined as a score of 0-2 on the modified Rankin Scale at 90 days. The safety outcome was mortality at 90 days and symptomatic intracranial hemorrhage within 48 h. Effect sizes were computed as risk ratio (RR) with random-effect models. This study was registered in PROSPERO (CRD42023462293).

RESULTS

A total of 528 articles were obtained through the search and articles that did not meet the inclusion criteria were excluded. Finally, 2 RCTs and 10 cohort studies met the inclusion criteria. The findings revealed that the endovascular thrombectomy alone group had a lower rate of functional independence compared to the bridging therapy group (29% vs 38%; RR 0.78, 95% CI 0.68-0.88, p < 0.001), lower independent ambulation (39% vs 45%; RR 0.89, 95% CI 0.82-0.98, p = 0.01), and higher mortality (36% vs 28%, RR 1.22, 95% CI 1.08-1.37, p = 0.001). However, no differences were detected in symptomatic intracranial hemorrhage between the two groups (6% vs 4%; RR 1.12, 95% CI 0.74-1.71, p = 0.58).

CONCLUSION

Intravenous thrombolysis plus endovascular thrombectomy seemed to led to better functional independence, independent ambulation, and lower risk of mortality without increasing the incidence of intracranial hemorrhage compared to endovascular thrombectomy alone. However, given the non-randomized nature of this study, further studies are needed to confirm these findings.

Influence of Bilateral Cerebellar Infarction on Functional Outcome After Endovascular Treatment for Basilar Artery Occlusion

BACKGROUND AND PURPOSE

To measure the magnitude of the effect of the infarct location measured using the posterior circulation Alberta Stroke Program Early Computed Tomographic Score (pc-ASPECTS) on the functional outcome at 90 days in patients with basilar artery (BA) occlusion undergoing endovascular therapy (EVT).

METHODS

Of the acute ischemic stroke patients undergoing EVT for acute posterior circulation large vessel occlusion enrolled in the multicenter observational registry from December 2013 to February 2021, patients with BA occlusion were included. A favorable outcome was defined as achieving a modified Rankin Scale score of 0-3 at 90 days. The effect of pc-ASPECTS including the distribution on favorable outcomes was evaluated.

RESULTS

One hundred patients were analyzed. Fifty-one patients (51%) achieved favorable outcome. Patients achieving a favorable outcome were younger, had a lower National Institutes of Health Stroke Scale score before EVT, and had a higher pc-ASPECTS before EVT than those not achieving a favorable outcome. Multivariable logistic analysis showed a significant association between higher pc-ASPECTS and a favorable outcome (odds ratio [OR] 1.24; 95% confidence interval [CI] 1.02-1.52; P = 0.028). Considering the infarct location, bilateral cerebellar infarction was significantly associated with a lower frequency of favorable outcomes than those without cerebellar infarction (OR 0.16; 95% CI 0.04-0.51; P = 0.002).

CONCLUSIONS

A higher pc-ASPECTS before EVT could be a predictor of a favorable outcome after EVT for BA occlusion. In particular, the presence of bilateral cerebellar infarction before EVT was significantly associated with a lower likelihood of a favorable outcome.

Endovascular treatment in patients with coma that developed secondary to acute basilar artery occlusion

OBJECTIVE

This study aimed to evaluate the efficacy of endovascular treatment (EVT) in patients with secondary coma following acute basilar artery occlusion (comatose patients) and to identify the impact of the Glasgow Coma Scale (GCS) score on medical decisions.

METHODS

Patients from the Endovascular Treatment for Acute Basilar Artery Occlusion study were divided into comatose and noncomatose cohorts. The primary outcome was favorable functional independence (modified Rankin Scale [mRS] scores 0-3). The safety outcome was 90-day mortality. Subgroup analysis was performed to identify populations best suited for EVT. Multivariate logistic regression was used to identify independent predictive factors of clinical outcomes.

RESULTS

Comatose patients who underwent EVT had more favorable functional outcomes and lower mortality compared with those who underwent standard medical treatment (functional outcomes: 15.98% vs 4.17%; mortality: 62.72% vs 82.29%). Moreover, EVT was associated with better outcomes in the cohort with GCS scores of 6-8 (mRS scores 0-3, 25.33% and mortality, 41.33%) than in the cohort with GCS scores of 3-5. Multivariate analysis indicated that EVT was an independent factor for favorable functional outcomes (adjusted OR 8.921, 95% CI 2.330-34.158) and mortality (adjusted OR 0.189, 95% CI 0.092-0.411) in comatose patients. The initial GCS score was an independent factor for favorable functional outcomes (adjusted OR 1.402, 95% CI 1.115-1.763) and mortality (adjusted OR 0.613, 95% CI 0.499-0.752) in comatose patients with EVT.

CONCLUSIONS

EVT significantly improved the prognosis of comatose patients, and patients with GCS scores of 6-8 were found to benefit more from EVT than those with GCS scores of 3-5. The initial GCS score was an independent predictive factor for prognosis in comatose patients.

Convulsive-like symptoms as initial indications of basilar artery occlusion: A case series study

Background:

There is little evidence regarding relevant clinical findings for the early diagnosis of basilar artery occlusion (BAO) in the prehospital setting. We focused on “convulsive-like symptoms”, including convulsive seizures and other convulsive-like movements, and examined the frequency and clinical characteristics of patients with BAO having these symptoms as an initial symptom.

Methods:

In this single-center case series from 2015 to 2020, we identified patients who underwent endovascular therapy (EVT) for BAO and presented with convulsive-like symptoms between the stroke onset and initiation of emergency medical care. The clinical course and neurological findings were evaluated by reviewing the run sheets of emergency medical services and medical records.

Results:

Among a total of 32 patients with BAO, 7 (21.9%) developed convulsive-like symptoms before EVT, of whom 6 were men and whose median age was 72 (interquartile range, 69–78) years. These 7 patients had no history of epilepsy or stroke, and the semiology of convulsive-like symptoms was generalized in 6 of them. In only 3 of the 7 cases, emergency medical services could consider the possibility of stroke on scene, and time from hospital arrival to groin puncture was longer in those who were transported without suspicion of stroke.

Conclusions:

21.9% of our patients who underwent EVT for BAO experienced convulsive-like symptoms initially. We should be vigilant in the possibility of BAO when managing the first-time generalized convulsive-like symptoms occurring in older patients, which may enable to adequate triage and better management for patients with acute BAO.

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Early diagnosis of basilar artery occlusion (BAO) is often challenging.

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In our analysis, 7 of 32 BAO patients developed “convulsive-like symptoms” initially.

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We outlined the clinical characteristics of these patients by chart review.

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First-time, and bilateral convulsive-like symptoms in elderly may predict BAO.

Acute Basilar Artery Occlusion Presenting With Convulsive Movements: A Systematic Review

Background and Purpose: Convulsive seizures related to posterior circulation stroke are considered rare. However, some patients with acute basilar artery occlusion (BAO) can present with convulsive movements. Misdiagnosed as seizures may delay the reperfusion therapy for acute BAO. In this study, we have summarized the clinical features and possible mechanisms of BAO presenting with convulsive movements.

Methods: We performed an Institutional Review Board-approved institutional database query from 2015 to 2020 and a literature search of the online database PubMed. Clinical data were collected and analyzed.

Results: In total, 14 patients with acute BAO presented with convulsions. There were 10 men and 4 women, with a mean age of 53 (range, 23–77) years. All of these patients had different degrees of impaired consciousness (100.0%, 14/14). Convulsive movements were the initial symptoms in 78.6% (11/14) of patients. Further, 64.3% (9/14) of patients presented with paralysis or cranial nerve abnormalities, and 85.7% (12/14) of patients were treated with reperfusion therapy (thrombolysis, 35.7% [5/14]; endovascular thrombectomy, 64.3% [9/14]). The BAO etiology and mechanism were related to embolism, vessel dissections, and severe stenosis of the right vertebral artery in 57.1% (8/14), 21.4% (3/14), and 7.1% (1/14) of patients, respectively; they were undefined in 14.3% (2/14) of patients. Moreover, 42.9% (6/14) of patients had a 90-day modified Rankin Scale score of 0–2, and the mortality rate was 21.4% (3/14).

Conclusions: Acute BAO, especially that related to embolism or vessel dissection, may present with convulsive movements. Acute BAO is a devastating, but treatable disease if diagnosed in time. Considering the possibility of BAO is important when dealing with patients presenting with acute-onset convulsive movements. Prompt diagnosis and reperfusion therapy may help achieve a better prognosis.

RAPID Software to the Clinical Application Value of Acute Basilar Artery Occlusion with Endovascular Treatment

OBJECTIVE

To investigate the clinical application value of RAPID software based on computed tomography perfusion imaging (CTP) in the endovascular treatment of acute basilar artery occlusion (BAO).

MATERIALS AND METHODS

The data of patients with acute basilar artery occlusion who received endovascular treatment in Taizhou Hospital, Zhejiang Province, between January 2020 and April 2021 were retrospectively analysed. The patients were divided into a perfusion imaging and a no-perfusion imaging group based on whether the image analysis results were obtained by RAPID software. Age, preoperative National Institute of Health stroke scale (NIHSS) score, onset to puncture time (OPT), operation methods, good prognosis at 3 months after surgery (modified Rankin scale (mRS) score ≤3), symptomatic intracranial haemorrhage (sICH) and other clinical data were compared between the two groups. Multivariate logistic regression analysis was used to identify the independent factors affecting the prognosis of BAO patients.

RESULTS

In total, 61 patients with acute BAO were included: 31 patients in the perfusion imaging group and 30 patients in the no-perfusion imaging group. There were no statistically significant differences between the two groups in age, NIHSS score or operation methods (all P >0.05). However, OPT and the good prognosis rate were significantly higher in the perfusion imaging group than in the no-perfusion imaging group (χ²=8.176, 5.003, P < 0.05). SICH was significantly lower in the perfusion imaging group than in the no-perfusion imaging group (χ²=5.628, P < 0.05). Logistic regression analysis showed that the image analysis results of RAPID software influenced the prognosis of EVT in patients with acute BAO (OR=4.048, 95%CI: 1.276-12.840).

CONCLUSIONS

RAPID software based on CTP can be used for preoperative screening of patients with acute basilar artery occlusion to identify those suitable for endovascular treatment, which is worthy of clinical promotion.

Stroke Etiology and Outcomes after Endovascular Thrombectomy: Results from the SITS Registry and a Meta-Analysis

BACKGROUND AND PURPOSE

The influence of stroke etiology on outcomes after endovascular thrombectomy (EVT) is not well understood. We aimed to investigate whether stroke etiology subgrouped as large artery atherosclerosis (LAA) and cardiac embolism (CE) influences outcomes in large artery occlusion (LAO) treated by EVT.

METHODS

We included EVT treated LAO stroke patients registered in the Safe Implementation of Treatment in Stroke (SITS) thrombectomy register between January 1, 2014 and September 3, 2019. Primary outcome was successful reperfusion (modified Treatment in Cerebral Infarction 2b-3). Secondary outcomes were symptomatic intracranial hemorrhage (SICH), 3-month functional independence (modified Ranking Scale 0-2) and death. Multivariable logistic regression models were used for comparisons. In addition, a meta-analysis of aggregate data from the current literature was conducted (PROSPERO, ID 167447).

RESULTS

Of 7,543 patients, 1,903 (25.2%) had LAA, 3,214 (42.6%) CE, and 2,426 (32.2%) unknown, other, or multiple etiologies. LAA patients were younger (66 vs. 74, P<0.001) and had lower National Institutes of Health Stroke Scale score at baseline (15 vs. 16, P<0.001) than CE patients. Multivariable analyses showed that LAA patients had lower odds of successful reperfusion (odds ratio [OR], 0.70; 95% confidence interval [CI], 0.57 to 0.86) and functional independence (OR, 0.74; 95% CI, 0.63 to 0.85), higher risk of death (OR, 1.44; 95% CI, 1.21 to 1.71), but no difference in SICH (OR, 1.09; 95% CI, 0.71 to 1.66) compared to CE patients. The systematic review found 25 studies matching the criteria. The meta-analysis did not find any difference between etiologies.

CONCLUSIONS

From the SITS thrombectomy register, we observed a lower chance of reperfusion and worse outcomes after thrombectomy in patients with LAA compared to CE etiology, despite more favorable baseline characteristics. In contrast, the meta-analysis did not find any difference between etiologies with aggregate data.

First approach to distinguish between cardiac and arteriosclerotic emboli of individual stroke patients applying the histological THROMBEX-classification rule

Endovascular treatment of strokes caused by large vessel occlusion enables the histopathological investigation of the retrieved embolus, possibly providing a novel opportunity to contribute to the diagnostic workup of etiology and to define secondary prevention measures in strokes with uncertain genesis. We aimed to develop a classification rule based on pathophysiological considerations and adjustment to reference thrombi for distinction between cardiac and arteriosclerotic emboli and to validate this classification rule on a patient cohort. From 125 patients with stroke due to large vessel occlusion and thrombectomy, 82 patients with known etiology (55 cardioembolic and 27 arterioembolic strokes) were included. The corresponding emboli were histologically evaluated by two raters blinded to the etiology of stroke by means of a novel classification rule. Presumed etiology and classification results were compared. Agreement concerning cardiac emboli was 72.2% (95% CI: 58.4–83.5) for rater I and 78.2% (95% CI: 65.0–88.2) for rater II. Agreement concerning arteriosclerotic emboli was 70.4% (95% CI: 49.8–86.3) for rater I and 74.1% (95% CI: 53.7–88.9) for rater II. Overall agreement reached 71.6% (95% CI: 60.5–81.1) for rater I and 76.8% (95% CI: 66.2–85.4) for rater II. Within the limits of generally restricted accuracy of histological evaluations, the classification rule differentiates between cardiac and arteriosclerotic emboli of acute ischemic stroke patients. Further improvement is needed to provide valuable complementary data for stroke etiology workup.

Endovascular intervention for basilar artery occlusion in the elderly

Background:

To date, few data have been reported on clinical outcomes following interventions in elderly populations with acute basilar artery occlusion. Using data from the Endovascular Treatment for Acute Basilar Artery Occlusion Study (BASILAR), we evaluated the efficacy and safety of intervention and determined predictors of outcomes among elderly patients in China.

Methods:

Patients from January 2014 to May 2019 were dichotomized into elderly (75 years or older) and nonelderly patients (under 75 years). Pearson’s Chi-square test and multivariate logistic regression were performed to assess 90-day favorable functional outcome (defined as a modified Rankin scale score of 0–3), mortality and symptomatic intracranial hemorrhage between intervention and conservative cohorts in elderly patients.

Results:

Among the 829 patients in the BASILAR, 182 patients aged 75 years or older were analyzed. These patients were divided into intervention (127 patients) and conservative (55 patients) cohorts. Compared with the conservative cohort, the intervention cohort presented more frequently with a favorable functional outcome (28.3% versus 12.7%; p = 0.023) and with a decreased mortality (54.3% versus 76.4%; p = 0.005). There was no difference in symptomatic intracranial hemorrhage (4.7% versus 0, p = 0.235). Multivariate analysis indicated that intervention was associated with favorable functional outcome (adjusted odds ratio, 0.262; 95% confidence interval, 0.088–0.778, p = 0.016) and lower mortality (adjusted odds ratio, 0.257; 95% confidence interval, 0.109–0.606, p = 0.002). In the intervention cohort, initial National Institutes of Health Stroke Scale (NIHSS) score and occlusion site were associated with functional outcome, and initial NIHSS score and recanalization were associated with mortality.

Conclusions:

Although the overall outcome following intervention was worse with age, intervention was more effective and safer than conservative treatment for elderly Chinese patients with basilar artery occlusion. Predictors of desirable outcome in elderly patients undergoing intervention included lower initial NIHSS score, occlusion site and successful recanalization.

Clinical Trial Registration-URL: http://www.chictr.org. Unique identifier: ChiCTR-1800014759

Endovascular treatment of acute basilar artery occlusion: Outcomes, influencing factors and imaging characteristics from the Tama-REgistry of acute thrombectomy (TREAT) study

OBJECTIVE

The effectiveness of mechanical thrombectomy (MT) for acute basilar artery occlusion (ABAO) remains unknown. We evaluated the feasibility, safety, and efficacy of endovascular treatment for ABAO.

METHODS

We retrospectively investigated patients with ABAO who underwent MT using modern stent retrievers and an aspiration device between January 2015 and March 2019 at 12 comprehensive stroke centers. Functional outcomes and 90-day mortality rates were analyzed as primary outcomes. Factors influencing outcomes were analyzed as secondary outcomes. Relationships between outcome and affected area of infarction on arrival were also analyzed.

RESULTS

Seventy-three patients were included. Good outcome (modified Rankin Scale (mRS) score 0-2) was achieved in 25/73 patients (34.2%) and the all-cause 90-day mortality rate was 23.3% (17/73). Successful recanalization (modified Thrombolysis In Cerebral Infarction grade 2b and 3) was achieved in 70/73 patients (95.9%). In univariate analyses, age, National Institutes of Health Stroke Scale score, and posterior circulation Alberta Stroke Program Early CT Score (pc-ASPECTS) differed significantly between good and poor functional outcome groups. Age and pc-ASPECTS were significantly associated with functional outcomes in the logistic regression model. Positive findings for the midbrain on diffusion-weighted imaging on pc-ASPECTS and brainstem score were significantly associated with poor outcomes.

CONCLUSION

MT with modern devices for ABAO resulted in highly successful recanalization and good outcomes. A positive finding for the midbrain on initial imaging might predict poor outcomes. Further studies are required to confirm our results.

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.

Similarities and Differences Between Primary Percutaneous Coronary Intervention and Mechanical Thrombectomy

Acute ischemic stroke is among the leading causes of mortality and disability worldwide. Since 2015, as was the case for primary percutaneous coronary intervention for acute myocardial infarction, catheter-based reperfusion via mechanical thrombectomy (MT) has become the gold-standard treatment for acute ischemic stroke caused by large-vessel occlusion. Despite that, only a fraction of the world's population currently would be able to undergo MT in time, mostly because of the scarcity of 24/7 coverage by neurointerventionalists to deal with this enormous burden. Interventional cardiologists have thus been considered a logical option to aid in combating this vast demand to diminish the burden of acute ischemic stroke. However, despite some seemingly evident similarities between primary percutaneous coronary intervention and MT, for interventional cardiologists to enter this new field, they must be well trained and fully aware of all the clinical, technical, and environmental differences between these two scenarios. The main objective of this state-of-the-art paper is to serve as an introductory and comprehensive guide to familiarize the interventional cardiology community with the most critical technical aspects of MT.

A Meta-Analysis of Prognostic Factors in Patients with Posterior Circulation Stroke after Mechanical Thrombectomy

BACKGROUND

Posterior circulation stroke is characterized by poor prognosis because its optimal thrombolysis "time window" is always missed. After mechanical thrombectomy (MT), the recanalization rate of posterior circulation obstruction is significantly increased, but prognosis remains poor. To best manage patients, prognostic factors are needed to inform MT triaging after posterior circulation stroke.

METHODS

A systematic literature search was done for the period through April 2020. Studies included those with posterior circulation stroke cases that underwent MT. The primary outcome measure in this study was the modified Rankin Scale on day 90.

RESULTS

No outcome differences were found in gender, atrial fibrillation, smoking, and coronary artery disease (OR = 1.07, 95% CI: 0.90-1.28; OR = 1.02, 95% CI: 0.82-1.26; OR = 1.26, 95% CI: 0.94-1.68; and OR = 0.84, 95% CI: 0.58-1.22, respectively). Hypertension, diabetes mellitus, and previous stroke correlated with poorer prognosis (OR = 0.61, 95% CI: 0.48-0.77; OR = 0.60, 95% CI: 0.50-0.73; and OR = 0.74, 95% CI: 0.55-0.99, respectively). However, hyperlipidemia correlated with better prognosis (OR = 1.28, 95% CI: 1.04-1.58).

CONCLUSION

Our analysis indicates that hypertension, diabetes mellitus, or previous stroke correlate with poorer outcomes. Intriguingly, hyperlipidemia correlates with better prognosis. These factors may help inform triage decisions when considering MT for posterior circulation stroke patients. However, large, multicenter, randomized controlled trials are needed to validate these observations.

Outcomes and long-term mortality after basilar artery occlusion-A cohort with up to 20 years' follow-up

BACKGROUND

The data on long-term outcome after basilar artery occlusion (BAO) are scarce. Little is known about BAO survivors´ outcome over decades.

AIM

We set out to investigate long-term survival and causes of death in BAO patients with up to two decades of follow-up. We also evaluated differences in outcome trends.

METHODS

Two hundred and seven BAO patients treated with intravenous thrombolysis (IVT) at the Department of Neurology, Helsinki University Hospital, between 1995 and 2016, were analyzed. Short-term outcome was assessed by modified Rankin Scale (mRS) at 3 months. Long-term cumulative survival rate was analyzed using Kaplan-Meier analysis. Factors associated with mortality were analyzed with Cox regression.

RESULTS

Moderate outcome (mRS 0-3) was achieved in 41.1% and good outcome (mRS 0-2) in 30.4% of patients at 3 months. Three-month mortality was 39.6%, of which 89% died within the first month. The median follow-up time in 3-month survivors was 8.9 years (maximum 21.8 years). Total mortality during follow-up was 52.2%. Cumulative mortality rate was 25.7%. Older age, coronary artery disease and more extensive ischemic changes on admission brain imaging were independently associated with long-term mortality. After the acute phase, the rate of other vascular causes of death increased in relation to stroke.

CONCLUSIONS

The described evolution of a large, single-center BAO cohort shows a trend towards a higher rate of good and/or moderate outcome during later years in IVT-treated patients. Survivors showed relative longevity, and the rate of cardiac and other vascular causes of death increased in relation to stroke sequelae over the long term.

Outcomes and Complications of Endovascular Mechanical Thrombectomy in the Treatment of Acute Posterior Circulation Occlusions: A Systematic Review

BACKGROUND

The use of thrombectomy in the treatment for acute ischemic stroke (AIS) affecting the anterior circulation is well established. Comparatively, fewer data exist on the effectiveness of these techniques in treating posterior circulation occlusions. This review analyzes and reports on the usefulness and outcomes of emergent thrombectomy in large-vessel occlusions affecting the posterior circulation.

METHODS

A literature review was performed to identify all studies of patients with AIS in the posterior circulation who underwent endovascular mechanical thrombectomy (EMT) with stent retrievers and/or aspiration devices that were reported between January 1, 2015 and February 12, 2019. Favorable outcomes were defined as a modified Rankin Scale (mRS) score 0-2 at 3 months follow-up. Successful reperfusion was defined as modified Thrombolysis in Cerebral Infarction score of 2b-3.

RESULTS

Twenty-five studies, comprising 1612 EMT-treated patients with posterior circulation AIS, were included in this analysis. The median presenting National Institutes of Health Stroke Scale score was 20.9 (range, 10.5-34). Favorable outcomes at 3 months follow-up were observed in 38% of patients (range, 16%-75%) and a mortality of 30% (range, 4%-64%). Successful reperfusion was achieved in 86% of cases (range, 62%-100%).

CONCLUSIONS

In patients with AIS caused by large-vessel occlusion of the posterior circulation, successful reperfusion can be achieved via EMT, with approximately a third of these patients achieving a good functional outcome. However, with similar proportions of treated patients experiencing significant morbidity or mortality, respectively, there is urgent need for additional studies to identify predictive or modifiable factors for a positive outcome.

Presenting NIHSS predicts 90-day functional outcome after mechanical thrombectomy for basilar artery occlusion: A systematic review and meta-analysis

The prediction of outcome after mechanical thrombectomy (MT) of basilar artery occlusion (BAO) remains an area of investigation. The objective of this study was to evaluate the prognostic role of presenting National Institute Health of Stroke Scale (NIHSS) scores in predicting favorable 90-day functional outcome. A survey of 7 electronic databases from inception to May 2020 was conducted following PRISMA guidelines. Articles were screened against pre-specified criteria. Multivariate odds ratios (ORs) for favorable 90-day function outcome (modified Rankin Score 0-2) were extracted and pooled by meta-analysis of proportions with random effects modeling. A total of 10 individual studies satisfied criteria for selection and described a total of 941 BAO patients managed by MT. Analysis revealed 590 (63%) males with a mean age of 66.6 years. The median presenting NIHSS was 19, and 316 (34%) patients were reported to have a favorable functional status 90-days after treatment. Lower presenting NIHSS scores independently and significantly predicted favorable 90-day functional outcome in BAO patients with a pooled OR of 0.89 (95% CI, 0.87-0.92; I² = 18%; P-heterogeneity = 0.28). Meta-regression did not detect any clinical parameter that influenced this trend direction or its significance, and bias assessments were unremarkable. We confirm in this study via a consensus within the literature that the presenting NIHSS score predicts 90-day functional outcome in BAO patients treated by MT. Further, its standardized use allows more meaningful comparisons between interventions and anatomical locations.

Aspiration Thrombectomy for Posterior Circulation Stroke: A Systematic Review and Meta-Analysis

PURPOSE

This study aims to analyze the efficacy of aspiration thrombectomy for large vessel occlusion of the posterior circulation, with an emphasis on comparison with stent retriever thrombectomy.

METHODS

A systematic review and meta-analysis were performed to analyze the outcomes of aspiration thrombectomy for acute posterior circulation stroke. For those studies that included data for both aspiration and stent-retriever thrombectomy, we additionally performed a second meta-analysis comparing their outcomes against each other.

RESULTS

A total of 17 articles were included. For the primary outcomes, the weighted pooled rate of mortality was 26.71% (95% confidence interval [CI] 19.35%-34.71%), modified Ranking Score (mRS) 0-2 at 3 months was 36.71 (95% CI 32.02%-41.52%), and successful recanalization 89.26% (95% CI 83.12%-94.31%). Primary stent retriever thrombectomy was inferior to primary aspiration thrombectomy for the outcomes of successful recanalization (odds ratio [OR] 0.57, 95% CI 0.36-0.91, P = 0.018), complete recanalization (OR 0.65, 95% CI 0.42-0.1.00, P = 0.048), procedure time (mean difference 28.17, 95% CI 9.47-46.87), and rate of embolization to new territory (OR 5.01, 95% CI 1.20-20.87, P = 0.027). No significant difference was seen for other outcomes. Further subgroup analysis suggests that for the outcome of recanalization, this may be dependent on the availability of second-line stent retriever thrombectomy.

LIMITATIONS

The included studies were observational in nature. There was unresolved heterogeneity in some of the outcomes.

CONCLUSIONS

There was no statistically significant difference seen for the primary outcomes of mortality and favorable outcome (mRS score 0-2) at 3 months. While superior rates of successful recanalization, complete recanalization, faster procedural time, and improved safety profile for primary aspiration thrombectomy were seen compared to primary stent retriever thrombectomy, this did not translate into superior clinical outcomes.

A Primer on Computed Tomography Perfusion Imaging for the Emergency Physician

BACKGROUND

Brain noncontrast computed tomography (CT), CT angiography, and magnetic resonance imaging have been used clinically for decades, and emergency physicians have a good understanding of their indications, the meaning of their results, and some facility with the interpretation of CT. However, brain CT perfusion (CTP) is relatively new and emergency physicians are less familiar with its basic concepts, indications, and role in managing patients with neurological emergencies.

OBJECTIVE

We will review the parameters of clinical interest on a CTP report, and how to incorporate them into clinical decision-making.

DISCUSSION

Endovascular therapies paired with CTP have opened up a new frontier in stroke management for severely debilitated stroke patients. It is important for emergency physicians to have an understanding of CTP and how to use it clinically.

CONCLUSION

Taking care of patients with large-vessel occlusions is multidisciplinary, and emergency physicians need to understand CTP imaging and its clinical utility.

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.

Avoiding Misdiagnosis in Patients With Posterior Circulation Ischemia: A Narrative Review

Posterior circulation strokes represent 20% of all acute ischemic strokes. Posterior circulation stroke patients are misdiagnosed twice as often compared to those with anterior events. Misdiagnosed patients likely have worse outcomes than correctly diagnosed patients because they are at risk for complications of the initial stroke as well as recurrent events due to lack of secondary stroke prevention and failure to treat the underlying vascular pathology. Understanding important anatomic variants, the clinical presentations, relevant physical examination findings, and the limitations of acute brain imaging may help reduce misdiagnosis. We present a symptom-based review of posterior circulation ischemia focusing on the subtler presentations with a brief discussion of basilar stroke, both of which can be missed by the emergency physician. Strategies to avoid misdiagnosis include establishing an abrupt onset of symptoms, awareness of the nonspecific presentations, consideration of basilar stroke in altered patients and using a modern approach to diagnosis of the acutely dizzy patient.

Mechanical thrombectomy in pediatric stroke: systematic review, individual patient data meta-analysis, and case series

OBJECTIVE

The role of mechanical thrombectomy in pediatric acute ischemic stroke is uncertain, despite extensive evidence of benefit in adults. The existing literature consists of several recent small single-arm cohort studies, as well as multiple prior small case series and case reports. Published reports of pediatric cases have increased markedly since 2015, after the publication of the positive trials in adults. The recent AHA/ASA Scientific Statement on this issue was informed predominantly by pre-2015 case reports and identified several knowledge gaps, including how young a child may undergo thrombectomy. A repeat systematic review and meta-analysis is warranted to help guide therapeutic decisions and address gaps in knowledge.

METHODS

Using PRISMA-IPD guidelines, the authors performed a systematic review of the literature from 1999 to April 2019 and individual patient data meta-analysis, with 2 independent reviewers. An additional series of 3 cases in adolescent males from one of the authors' centers was also included. The primary outcomes were the rate of good long-term (mRS score 0-2 at final follow-up) and short-term (reduction in NIHSS score by ≥ 8 points or NIHSS score 0-1 at up to 24 hours post-thrombectomy) neurological outcomes following mechanical thrombectomy for acute ischemic stroke in patients < 18 years of age. The secondary outcome was the rate of successful angiographic recanalization (mTICI score 2b/3).

RESULTS

The authors' review yielded 113 cases of mechanical thrombectomy in 110 pediatric patients. Although complete follow-up data are not available for all patients, 87 of 96 (90.6%) had good long-term neurological outcomes (mRS score 0-2), 55 of 79 (69.6%) had good short-term neurological outcomes, and 86 of 98 (87.8%) had successful angiographic recanalization (mTICI score 2b/3). Death occurred in 2 patients and symptomatic intracranial hemorrhage in 1 patient. Sixteen published thrombectomy cases were identified in children < 5 years of age.

CONCLUSIONS

Mechanical thrombectomy may be considered for acute ischemic stroke due to large vessel occlusion (ICA terminus, M1, basilar artery) in patients aged 1-18 years (Level C evidence; Class IIb recommendation). The existing evidence base is likely affected by selection and publication bias. A prospective multinational registry is recommended as the next investigative step.

Endovascular treatment of acute basilar artery occlusion: Tama-REgistry of Acute Thrombectomy (TREAT) study

OBJECTIVE

The effectiveness of mechanical thrombectomy (MT) for acute basilar artery occlusion (ABAO) remains unknown. We evaluated the feasibility, safety, and efficacy of endovascular treatment for ABAO.

METHODS

We retrospectively investigated patients with ABAO who underwent MT, using modern stent retrievers and an aspiration device, between January 2015 and December 2017 at 12 comprehensive stroke centers. Functional outcomes and 90-day mortality were analyzed as primary outcomes.

RESULTS

Forty-eight patients were included. Good outcome (modified Rankin Scale mRS 0-2) was achieved in 20/48 patients and the all-cause 90-day mortality rate was 25%. Successful recanalization (modified Thrombolysis In Cerebral Infarction [mTICI] grade 2b and 3) was achieved in 47/48 patients. National Institutes of Health Stroke Scale, posterior circulation Alberta Stroke Program Early CT Score (pc-ASPECTS), DWI Brain Stem Score, mTICI (3 > 2b), and intracranial hemorrhage were significantly different between good and poor functional outcome groups. The occlusion site of BA was significantly different between patients with moderate outcome (mRS 0-3) versus others. We found that age, pc-ASPECTS and mTICI were significantly associated with functional outcomes in the logistic regression model.

CONCLUSION

MT with stent retrievers and an aspiration device for ABAO results in high successful recanalization and good outcomes. Further studies are required to confirm our results.

Vertebral Artery Patency and Thrombectomy in Basilar Artery Occlusions

Background and Purpose—

Factors influencing recanalization success in basilar artery occlusions are largely unknown. Preliminary evidence has suggested that flow arrest in the vertebral artery contralateral to the catheter bearing vertebral artery may facilitate recanalization. The aim of this analysis was to assess the impact of anatomic variations and flow conditions on recanalization success in basilar artery occlusion treated with mechanical thrombectomy.

Methods—

Consecutive basilar artery occlusions treated with second-generation thrombectomy devices at a single-center were retrospectively analyzed. Baseline patients’ characteristics, occlusion length, collateral circulation, underlying stenosis, incomplete occlusions, and patency of the vertebral arteries were analyzed with regards to recanalization success. Aplastic or hypoplastic vertebral artery contralateral to the catheter position was defined as contralateral low flow condition. Logistic regression analysis was used to examine the association between anatomic variations and flow conditions in relation to complete recanalization and the modified Rankin Scale score while controlling for several potentially confounding variables. Clinical impact was evaluated using the modified Rankin Scale score of ≤3.

Results—

One hundred fifteen patients were included (mean age 71.5±12.8, m:f=2:1, median National Institutes of Health Stroke Scale =15, interquartile range =10–22). Complete recanalization was more often observed in patients with contralateral low flow conditions (80.6% versus 50.0%), which remained an independent predictor of complete recanalization in multivariable analysis (adjusted odds ratio, 5.81; 95% CI, 1.97–17.19). Patients with complete posterior recanalization had lower in-hospital mortality (16.4% versus 41.7%) and more often achieved modified Rankin Scale score of ≤3 (49.4% versus 8.3%), even after adjusting for potential confounders (adjusted odds ratio, 15.93; 95% CI, 1.42–179.00).

Conclusions—

Contralateral low flow condition (vertebral artery aplasia or hypoplasia) seems to be an independent factor for fewer distal emboli and complete recanalization in basilar artery occlusion patients treated by modern endovascular devices. Complete recanalization reflecting the absence of peri-interventional clot fragmentation brings clear clinical benefit. Further studies are warranted to evaluate the need for contralateral flow modulation or ipsilateral balloon guide catheter during posterior circulation thrombectomy in patients with bilaterally patent vertebral arteries.

Basilar Artery Occlusion with "Seizures" as a Presenting Symptom: Three Cases Treated Using Mechanical Thrombectomy

BACKGROUND

Basilar artery occlusion (BAO) is a rare, potentially fatal cause of ischemic stroke. It is often challenging to diagnose, especially when the presenting symptom is "seizures". We present 3 cases of patients with BAO presenting with seizures.

CASE DESCRIPTION

The first patient was a 53-year-old man with clonic convulsions. On angiography, BAO was detected and mechanical thrombectomy (MT) was performed. The modified Rankin Scale score at 3 months after treatment was 1. The second patient was a 64-year-old man with generalized convulsions. He was diagnosed with BAO and vertebral artery dissection and was treated with MT, percutaneous transluminal angioplasty, and stenting. The modified Rankin Scale score at 3 months after treatment was 3. The third patient was a 77-year-old man with tonic convulsions. He was diagnosed with BAO and treated with MT. However, he did not survive.

CONCLUSIONS

BAO is devastating; however, it is a treatable disease. Our report suggests that BAO should be suspected in patients presenting with initial convulsive seizures.

Diagnosis of Hyperacute and Acute Ischaemic Stroke: The Potential Utility of Exosomal MicroRNA-21-5p and MicroRNA-30a-5p

BACKGROUND

Early and accurate diagnosis of ischaemic stroke (IS) requires the use of an optimized biomarker. Exosomal microRNAs have the potential to serve as biomarkers owing to their stability and specificity. We investigated the expression levels of plasma-derived exosomal microRNA-21-5p and microRNA-30a-5p in the different phases of IS.

METHODS

One hundred forty-three patients with IS and 24 non-stroke controls were enrolled. The patients were divided into the following 5 groups: 1 group for the hyperacute phase IS (HIS, within 6 h); two for the acute phase IS (AIS, including days 1-3 and days 4-7); one for the subacute phase IS (SIS, days 8-14); and one for the recovery phase IS (RIS, days >14). Plasma exosomes were isolated using a QIAGEN exoRNeasy kit and examined by transmission electron -microscopy, nanoparticle tracking, and flow cytometry. The expression levels of miRNA-21-5p and miRNA-30a-5p were detected by quantitative real-time polymerase chain reaction.

RESULTS

The plasma exosomal miR-21-5p levels in SIS and RIS were significantly higher than that in controls (p < 0.05 and p < 0.01 respectively). The levels of miR-30a-5p in HIS were significantly higher (p < 0.05) and in AIS (days 1-3) were lower than that in controls (p < 0.05). In AIS (days 1-3), both miRNAs were decreased compared with the HIS group (p = 0.053 and 0.001, respectively). The area under the curve (AUC) of the miR-21-5p was 0.714 for SIS (95% CI 0.570-0.859, p = 0.007), 0.734 for RIS (95% CI 0.596-0.871, p = 0.003); the AUC of the miR-30a-5p was 0.826 for HIS (95% CI 0.665-0.988, p = 0.001), 0.438 for AIS (days 1-3; 95% CI 0.240-0.635, p = 0.516).

CONCLUSIONS

The plasma-derived exosomal miR-21-5p and miRNA-30a-5p in combination are promising biomarkers for diagnosing IS and distinguishing among HIS, SIS, and RIS, especially miRNA-30a-5p for the diagnosis of the HIS phase. Our results provide a new reference for clinicians to apply in early-stage diagnosis and identifies the possible value of biomarkers for IS thrombolysis therapy.