Outcomes of stent retriever thrombectomy in basilar artery occlusion: an observational study and systematic review

Expanding indications for endovascular thrombectomy-how to leave no patient behind

Endovascular thrombectomy (EVT) has become standard of care for large vessel occlusion strokes but current guidelines exclude a large proportion of patients from this highly effective treatment. This review therefore focuses on expanding indications for EVT in several borderline indications such as patients in the extended time window, patients with extensive signs of infarction on admission imaging, elderly patients and patients with pre-existing deficits. It also discusses the current knowledge on intravenous thrombolysis as an adjunct to EVT and EVT as primary therapy for distal vessel occlusions, for tandem occlusions, for basilar artery occlusions and in pediatric patients. We provide clear recommendations based on current guidelines and further literature.

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.

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.

Age and discharge modified Rankin score are associated with 90-Day functional outcome after basilar artery occlusion treated with endovascular therapy

INTRODUCTION

Prognostic factors for functional outcome after basilar artery occlusion (BAO) treated with modern endovascular therapy (EVT) are sparse. We investigated the association between clinical characteristics, readily available imaging variables, and outcome in BAO patients treated with EVT.

METHODS

Retrospective analysis from a large healthcare system's prospectively collected code stroke registry of acute BAO patients treated with EVT between January 2017-January 2020. The primary outcome measure was a favorable 90-day modified Rankin score (mRS) of 0-2.

RESULTS

65 patients (median age 67 years, 57% male, median NIHSS 16) met the study inclusion criteria. Thrombolysis in Cerebral Infarction (TICI) 2 b-3 revascularization was achieved in 57/65 patients (88%) with a median time to revascularization of 445 minutes [IQR 302-840]. Ninety-day good outcome was seen in 35% (23/65) of patients. In a univariate analysis, age, history of ischemic stroke, baseline NIHSS, BAO site, and discharge mRS were associated with significant differences between the good and poor outcome groups. A multivariable logistic regression analysis demonstrated an independent association with 90-day good outcome and younger age (per 1-year, OR 0.79, 95% CI 0.64, 0.98) and good discharge mRS (0-2) (OR > 999.99, 95% CI 13.26, > 999.99).

CONCLUSIONS

Patients presenting with an acute BAO treated with modern EVT have a good 90-day outcome in over one-third of cases. Age and discharge mRS are independently associated with good 90-day outcome. Additional studies may focus on factors that can enhance discharge function after BAO, a novel prognostic indicator for favorable 90-day outcome in our study.

Acute ischemic stroke endovascular therapy

Endovascular therapy (EVT) has become the standard treatment for large-vessel occlusion (LVO) acute ischemic stroke (AIS). EVT is now indicated in patients up to 24h from their last known well, provided that the patient meets specific clinical and imaging criteria. Improvements in thrombectomy devices, techniques, and operator experience have allowed successful EVT of ICA terminus, M1-MCA occlusions as well as proximal M2-MCA, basilar artery occlusions, and revascularization of tandem lesions. Mechanical thrombectomy failures still occur due to several factors, however, highlighting the need for further device and technical improvements. An ongoing debate exists regarding the need for pre-EVT thrombolytic agents, thrombectomy techniques, distal occlusions, anesthesia methods, the role of advanced neuroimaging, the treatment of patients with larger infarct core, and those presenting with milder stroke symptoms. Many of these questions are the subject of current or upcoming clinical trials. This review aims to provide an outline and discussion about the established recommendations and emerging topics regarding EVT for LVO AIS.

Coronary stent implantation for acute basilar artery occlusion with underlying stenosis

AIMS

Our aim was to study the effectiveness of coronary stent implantation during the endovascular treatment (EVT) of acute basilar artery occlusion (BAO) with occlusion-underlying intracranial atherosclerotic stenosis (ICAS).

METHODS AND RESULTS

We retrospectively analysed 91 consecutive BAO patients who underwent EVT between February 2014 and January 2019 in a single, high-volume neurointerventional centre. We studied the effect of immediate coronary stent implantation on the clinical outcome of BAO with occlusion-underlying stenosis. BAO patients with underlying ICAS (n=41) were characterised by longer symptom-onset-to-reperfusion times (231 min vs 173 min, p=0.0020), lower TICI 2b-3 reperfusion rates (65.85% vs 90.00%, p=0.0084), and higher overall mortality (HR 2.021, p=0.0417) compared to the BAO cases without ICAS (n=50). The patients undergoing stenting (n=18) had lower residual basilar artery (BA) stenosis (14.7% vs 81.0%, p<0.0001), higher chance for functional recovery (OR 7.6, p=0.0250) and higher chance of survival (HR 4.163, p=0.0026) compared to the BAO-ICAS cases treated without coronary stents (n=21).

CONCLUSIONS

The immediate treatment of the occlusion-underlying stenosis with coronary stents and dual antiplatelet therapy (DAPT) in BAO was associated with improved overall survival and better functional outcomes.

Thrombectomy for Posterior Circulation Stroke: Predictors of Outcomes in a Brazilian Registry

BACKGROUND

Acute basilar artery occlusion is a devastating life-threatening condition. Early recanalization is the therapeutic goal in patients with acute ischemic stroke. Despite the high rates of recanalization achieved with modern devices for basilar occlusions, many patients have had poor clinical outcomes. This study aimed to assess the predictors of good and poor outcomes among patients with basilar artery occlusion treated with thrombectomy.

METHODS

A consecutive registry of 80 patients was included in this retrospective study. The primary end point was to access variables associated with neurologic outcomes defined by a modified Rankin Scale (mRS) score of 0-2, symptomatic intracranial hemorrhage (sICH), and mortality at 3 months follow-up.

RESULTS

Recanalization was achieved in 86.2%, and the sICH rate was 8.7%. A good neurologic outcome (mRS score 0-2) was observed in 26.2% and a moderate outcome (mRS score 0-3) in 32.5% of patients. The mortality was 38.7% at 3 months follow-up.

CONCLUSIONS

After thrombectomy for posterior circulation strokes, young patients, V4-proximal basilar occlusion, (high) baseline posterior circulation Alberta Stroke Program Early CT Score, and complete recanalization were independent predictors of good neurologic outcomes. Failure to recanalize was strongly related to sICH and mortality. In addition, diabetes, atrial fibrillation, and baseline National Institutes of Health Stroke Scale scores ≥10 had an independent association with mortality. This study contributes to the knowledge required to optimize recanalization treatments for posterior circulation strokes and may help to improve future clinical studies.

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.

Diagnosis of Coma

The differential diagnosis for the comatose patient is includes structural abnormality, seizure, encephalitis, metabolic derangements, and toxicologic etiologies. Identifying and treating the underlying pathology in a timely manner is critical for the patient's outcome. We provide a structured approach to taking a history and performing a physical examination for this patient population. We discuss diagnostic testing and treatment methodologies for each of the common causes of coma. Our current understanding of the mechanisms of coma is insufficient to accurately predict the patient's clinical trajectory and more work needs to be done to investigate potential treatments for this often fatal disorder.

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.

Mechanical Thrombectomy in Patients With Acute Ischemic Stroke: A Comparison of Transradial Versus Transfemoral Cerebral Angiography

Stroke is the fourth leading cause of death in the United States and the primary reason for long-term disability. This debilitating condition can be divided into ischemic stroke and hemorrhagic stroke. The former occurs in almost 90% of all cases and arises from the occlusion of the supplying artery. Over the years, the management of stroke has developed from solely medical treatment to that which combines medical with mechanical treatment. Mechanical thrombectomy (MT) has drawn considerable interest in advanced medicine and is becoming more widely available. The two fundamental techniques in opening an occluded vessel are the transfemoral and transradial approaches. This literature review aims to compare the clinical implications, complication rate, and overall outcome between the transfemoral and transradial approaches in endovascular intervention in patients with acute ischemic stroke. We conducted a literature review on ischemic stroke and searched PubMed and Google Scholar for relevant articles published from January 2010 to March 2020. Mechanical thrombectomy has become the standard of care for patients with brain ischemia. The transradial approach exhibited superiority to the transfemoral route in resolving symptoms, decreased complication rates, and reduced healthcare costs in a subset of patients. In this literature review, the comparison between the two procedures reveals that the outcomes for anterior circulation stroke and posterior vascular system stroke may vary. Further research needs to be conducted to improve procedural skills and decrease technical difficulties, ultimately resulting in improved overall patient outcomes with respect to health and comfort. 

Outcome and recanalization rate of tandem basilar artery occlusion treated by mechanical thrombectomy

BACKGROUND

Tandem basilar artery occlusions (tBAO) are defined as concomitant basilar artery and extracranial dominant vertebral artery occlusions. The prognosis of such tBAO treated by mechanical thrombectomy (MT) has been scantly reported. The purpose of our study was to compare the safety and effectiveness of MT for patients with tBAO compared to those with non-tandem basilar artery occlusions (ntBAO).

PATIENTS AND METHODS

Retrospective analysis of a database of patients who underwent MT at two academic centres. All patients treated for BAO were retrieved. Patients with tBAO, defined as a concomitant BAO and extracranial vertebral artery (VA) occlusion or severe stenosis ≥70% (V1 or proximal V2 segment) were compared with patients with ntBAO.

RESULTS

A total of 15 patients with tBAO and 74 patients with ntBAO were enrolled. Successful reperfusion (modified thrombolysis in cerebral infarction score ≥2b) was obtained in 73.3% versus 90.5% (OR = 0.29, 95%CI: 0.07-1.15), good clinical outcome (3-months modified Rankin scale ≤2) was reached by 26.7% versus 32.4% (OR = 0.76; 95% CI: 0.24-2.63) and mortality at 3-months was 46.7% versus 31% (OR = 1.94; 95%CI: 0.63-6) of patients with tBAO versus ntBAO, respectively. Two patients (13.3%) with tBAO and three (4%) with ntBAO had symptomatic intracranial haemorrhage (OR = 3.64; 95% CI: 0.55-24).

CONCLUSION

Mechanical thrombectomy for patients with tandem basilar artery occlusion tends to be associated with lower rates of successful reperfusion and good clinical outcome, and higher rate of mortality. Larger multicentre studies are warranted to better precise the proper selection and management of such patients.

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.

Endovascular treatment combined with vertebral artery endarterectomy for patients with acute tandem vertebrobasilar artery occlusion

PURPOSE

To evaluate the safety and efficacy of endovascular treatment combined with vertebral artery endarterectomy in patients with acute tandem vertebrobasilar artery occlusion.

METHODS

From April 2017 to March 2019, three patients with acute basilar artery occlusion combined with ostial vertebral occlusion in our institution were enrolled in the study. They underwent endovascular treatment combined with vertebral artery endarterectomy. The clinical, technical and functional outcomes of the patients were retrospectively analysed.

RESULTS

All three patients in the study underwent complete recanalization. The modified Thrombolysis in Cerebral Infarction (mTICI) grade was 2b/3 in all patients. The modified Rankin Scale (mRS) score was 0-2 for the three patients at 3 months. Follow-up CT scans revealed no cerebral haemorrhage, and no patients died during follow-up. All patients achieved good clinical outcomes after the combined treatment.

CONCLUSION

Endovascular treatment combined with vertebral artery endarterectomy is a feasible method to treat patients with acute basilar artery occlusion combined with ostial vertebral occlusion, especially when the guidewire cannot pass through the ostium of the dominant vertebral artery occlusion.

Choice of ANaesthesia for EndoVAScular treatment of acute ischaemic stroke at posterior circulation (CANVAS II): protocol for an exploratory randomised controlled study

INTRODUCTION

Observational and interventional studies indicate that the type of anaesthesia may be associated with the postprocedural neurological function in patients with anterior circulation acute ischaemic stroke undergoing endovascular treatment. Patients with acute posterior circulation ischaemic stroke may experience different physiological changes and result in severe neurological outcome. However, the effect of the type of anaesthesia on postprocedure neurological function remained unclear in this population.

METHODS AND ANALYSIS

This is an exploratory randomised controlled trial that will be carried out at Beijing Tiantan Hospital, Capital Medical University. Patients with acute posterior circulation ischaemic stroke and deemed suitable for emergency endovascular recanalisation will be recruited in this trial. Eighty-four patients will be randomised to receive either general anaesthesia or conscious sedation with 1:1 allocation ratio. The primary endpoint is the 90-day modified Rankin Scale.

ETHICS AND DISSEMINATION

The study has been reviewed by and approved by Ethics Committee of Beijing Tiantan Hospital of Capital Medical University (KY2017-074-02). If the results are positive, the study will indicate whether the type of anaesthesia affects neurological outcome after endovascular treatment of posterior stroke. The findings of the study will be published in peer-reviewed journals and presented at national or international conferences.

TRIAL REGISTRATION NUMBER

NCT03317535.

Predicting outcomes after acute reperfusion therapy for basilar artery occlusion

BACKGROUND AND PURPOSE

Basilar artery occlusion (BAO) leads to high rates of morbidity and mortality, despite successful recanalization. The discordance between flow restoration and long-term functional status clouds clinical decision-making regarding further aggressive care. We sought to develop and validate a practical, prognostic tool for the prediction of 3-month favorable outcome after acute reperfusion therapy for BAO.

METHODS

This retrospective, multicenter, observational study was conducted at four high-volume stroke centers in the USA and Europe. Multivariate regression analysis was performed to identify predictors of favorable outcome (90-day modified Rankin scale scores 0-2) and derive a clinically applicable prognostic model (the Pittsburgh Outcomes after Stroke Thrombectomy-Vertebrobasilar (POST-VB) score). The POST-VB score was evaluated and internally validated with regard to calibration and discriminatory ability. External validity was assessed in patient cohorts at three separate centers.

RESULTS

In the derivation cohort of 59 patients, independent predictors of favorable outcome included smaller brainstem infarct volume on post-procedure magnetic resonance imaging (P < 0.01) and younger age (P = 0.01). POST-VB score was calculated as: age + (10 × brainstem infarct volume). POST-VB score demonstrated excellent discriminatory ability [area under the receiver-operating characteristic curve (AUC) = 0.91] and adequate calibration (P = 0.88) in the derivation cohort (Center A). It performed equally well across the three external validation cohorts (Center B, AUC = 0.89; Center C, AUC = 0.78; Center D, AUC = 0.80). Overall, a POST-VB score < 49 was associated with an 88% likelihood of favorable outcome, as compared to 4% with a score ≥ 125.

CONCLUSIONS

The POST-VB score effectively predicts 3-month functional outcome following acute reperfusion therapy for BAO and may aid in guiding post-procedural care.

Thrombectomy Technique Predicts Outcome in Posterior Circulation Stroke—Insights from the STAR Collaboration

BACKGROUND

Randomized controlled trials evaluating mechanical thrombectomy (MT) for acute ischemic stroke predominantly studied anterior circulation patients. Both procedural and clinical predictors of outcome in posterior circulation patients have not been evaluated in large cohort studies.

OBJECTIVE

To investigate technical and clinical predictors of functional independence after posterior circulation MT while comparing different frontline thrombectomy techniques.

METHODS

In a retrospective multicenter international study of 3045 patients undergoing MT for stroke between 06/2014 and 12/2018, 345 patients had posterior circulation strokes. MT was performed using aspiration, stent retriever, or combined approach. Functional outcomes were assessed using the 90-d modified Rankin score dichotomized into good (0-2) and poor outcomes (3-6).

RESULTS

We included 2700 patients with anterior circulation and 345 patients with posterior circulation strokes. Posterior patients (age: 60 ± 14, 46% females) presented with mainly basilar occlusion (80%) and were treated using contact aspiration or ADAPT (39%), stent retriever (31%) or combined approach (19%). Compared to anterior strokes, posterior strokes had delayed treatment (500 vs 340 min, P &lt; .001), higher national institute of health stroke scale (NIHSS) (17.1 vs 15.7, P &lt; .01) and lower rates of good outcomes (31% vs 43%, P &lt; .01). In posterior MT, diabetes (OR = 0.28, 95%CI: 0.12-0.65), admission NIHSS (OR = 0.9, 95%CI: 0.86-0.94), and use of stent retriever (OR = 0.26, 95%CI: 0.11-0.62) or combined approach (OR = 0.35, 95%CI: 0.12-1.01) vs ADAPT were associated with lower odds of good outcome. Stent retriever use was associated with lower odds of good outcomes compared to ADAPT even when including patients with only basilar occlusion or with successful recanalization only.

CONCLUSION

Despite similar safety profiles, use of ADAPT is associated with higher rates of functional independence after posterior circulation thrombectomy compared to stent retriever or combined approach in large “real-world” retrospective study.

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.

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.

Glasgow Coma Scale on Presentation Predicts Outcome in Endovascular Treatment for Acute Posterior Large-Vessel Occlusion

Use of mechanical thrombectomy for stroke has increased since the publication of trials describing outcome improvement when used in the anterior circulation. These results, however, cannot be directly translated to the posterior circulation. While a high NIHSS score has demonstrated an association with poor outcomes in posterior stroke, the NIHSS is weighted toward hemispheric disease, and complex scores potentially delay definitive imaging diagnosis. We performed a retrospective analysis to ascertain whether any rapidly obtainable demographic or clinical and imaging data have a correlation with patient outcome postthrombectomy. Seventy-three cases were audited between September 2010 and October 2017. Presenting with a Glasgow Coma Scale score of >13 meant that the odds of reaching the primary end point of functional independence (defined as a 90-day modified Rankin Scale score of 0-2) were 5.70 times greater; similarly, presenting with a posterior circulation ASPECTS of  >9 resulted in the odds of reaching the primary end point being 4.03 times greater. Older age correlated to a lower odds of independence (0.97, p = .04).

Mechanical Thrombectomy for Posterior Circulation Occlusion: A Comparison of Outcomes with the Anterior Circulation Occlusion - A Meta-Analysis

Aim: There is no randomized controlled trial to compare the effectiveness and safety of mechanical thrombectomy (MT) to intravenous thrombolysis in patients with posterior circulation occlusion (PCO). Hence, we firstly performed a meta-analysis to investigate the outcomes of MT in PCO and then compared these outcomes to anterior circulation occlusion (ACO) to provide fundamental data to further studies.

Methods: We searched the PubMed, EMBASE, and Cochrane Library from dates of inception to June 2019 for relevant studies. Outcomes including functional independence at 90 days, successful recanalization, mortality, symptomatic intracranial hemorrhage (sICH), and futile recanalization were extracted.

Results: Seven studies involving 474 patients with PCO thrombectomy were analyzed. There was a lower rate of functional independence at 90 days and a higher rate of mortality after thrombectomy in PCO versus ACO (odds ratios (OR) 0.72; 95% confidence interval (CI) 0.57–0.90; OR 2.03; 95% CI 1.30–3.18). Recanalization rates were comparable (OR 1.01; 95% CI 0.62–1.65), but a higher futile recanalization rate was found in basilar artery occlusion (BAO) (OR 1.75; 95% CI 1.30–2.37). There was a lower rate of sICH in MT for patients with PCO versus ACO (OR 0.54; 95% CI 0.29–0.99).

Conclusions: We found that the outcomes of MT for patients with PCO were poorer than with ACO. On the other hand, MT appears to have lower rates of sICH and to increase successful recanalization. Given the high recanalization rate, MT may serve as an adjunct to standard treatment. The key point to improve outcomes is recognizing reliable factors associated with futile recanalization and optimizing the results of MT. But in view of the different characteristics of posterior circulation stroke and anterior circulation stroke, the results are far from robust.

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.

Recanalization is the Key for Better Outcome of Thrombectomy in Basilar Artery Occlusion

PURPOSE

Patients with basilar artery occlusion (BAO) were excluded from previous randomized controlled trials (RCTs) of endovascular treatment (ET) for acute ischemic stroke, but are commonly treated in clinical practice. This study aimed at analyzing predictors of functional outcome of ET in patients with BAO to improve patient selection for ET.

METHODS

Consecutive patients with BAO who received ET over a 2-year time period were prospectively studied. Baseline characteristics, procedural and outcome data were evaluated. Outcome was assessed by the modified Rankin Scale (mRS) 90 days after stroke. Multivariate regression analyses were performed to identify predictors of outcome across the range of the mRS, of poor outcome (mRS 5-6) and independent outcome (mRS 0-2).

RESULTS

A total of 39 patients with BAO (median age: 75 years, 67% male) were included. Median baseline National Institutes of Health Stroke Scale (NIHSS) score was 24. Intravenous thrombolysis therapy (IVT) was administered in 56%. Successful recanalization assessed by a modified thrombolysis in cerebral infarction (TICI) score ≥2b was achieved in 82%. Independent outcome was observed in 30% of patients with successful recanalization, but in no patient with failed recanalization. Poor outcome was observed in 47% and 86%, respectively. Successful recanalization was associated with lower scores on the mRS at 90 days (p = 0.035), and failed recanalization was associated with an odds ratio of 13.6 for poor outcome (p = 0.036).

CONCLUSION

Reperfusion is the major predictor of functional outcome in BAO in clinical practice. Failed recanalization resulted in a 13-fold increase of the risk of poor outcome. Successful recanalization is crucial to achieve a better functional outcome in BAO.

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.

Endovascular treatment for acute basilar artery occlusion: a single center retrospective observational study

Background

Endovascular treatment (EVT) is now considered the gold standard for select patient populations with anterior circulation stroke; however, data on the treatment of posterior circulation stroke are less clear. This study aims to determine the characteristics and treatment outcomes of patients with acute basilar artery occlusion (BAO) and to evaluate the effectiveness and safety of EVT for patients with acute BAO in a high-volume stroke center.

Methods

This study included 187 consecutive patients with acute BAO who underwent EVT from January 2012 to July 2018 in the Beijing Tiantan Hospital. The baseline characteristics, procedure parameters, and functional outcome were assessed.

Results

Among the 187 patients, 138 (73.8%) underwent mechanical thrombectomy with a stent retriever, 33 (17.6%) underwent direct intracranial angioplasty (balloon dilation and/or stent implantation) for underlying severe intracranial atherosclerotic disease, and 91 (48.7%) underwent combined mechanical thrombectomy and angioplasty. Successful recanalization [modified Thrombolysis in Cerebral Infarction (mTICI) grade 2b-3] was achieved in 158 patients (84.5%). Overall, the rates of functional independence [modified Rankin Scale (mRS) 0–2] and favorable outcome (mRS 0–3) at 90 days were 36.4 and 49.2%, respectively, and 90-day all-cause mortality was 20.3%.

Conclusion

EVT was effective and safe for treating patients with acute BAO.

Mechanical Thrombectomy for Basilar Artery Occlusion Compared with Anterior Circulation Stroke

OBJECTIVE

To investigate the clinical effectiveness of mechanical thrombectomy (MT) for basilar artery occlusion (BAO) and to ascertain whether outcomes for patients with BAO were comparable to those with anterior circulation large vessel occlusion (ACS).

METHODS

A total of 345 patients who underwent MT between 2011 and 2018 were grouped by occlusion site (295 patients with ACS and 50 patients with BAO). Patients' baseline characteristics, procedural times, complications, symptomatic intracranial hemorrhage, modified Rankin Scale score, and mortality at 90 days were analyzed.

RESULTS

Male preponderance (66.0% vs. 48.8%; P = 0.0316), younger age (72.5 years [interquartile range (IQR), 64.75-78.5 years] vs. 77 years [IQR 69-84 years]; P = 0.0297), higher National Institutes of Health Stroke Scale score (24.5 [IQR, 13-32] vs. 18 [IQR 13-22]; P = 0.0015) and higher reperfusion rate (100% vs. 84.7%; P = 0.0010) were observed in patients with BAO. We found no significant difference in favorable outcomes (modified Rankin Scale score ≤2) between patients with BAO and patients with ACS (64.3% vs. 49.3%; P = 0.0914). In multivariate analysis, Alberta Stroke Program Early Computed Tomography Score (odds ratio [OR], 1.282; 95% confidence interval [CI], 1.090-1.524; P = 0.0024), time from onset to reperfusion (OTR) (OR, 0.9950; 95% CI, 0.992-0.998; P = 0.0008), successful reperfusion (OR, 6.953; 95% CI, 1.576-48.729; P = 0.0092), and hemorrhagic complication (OR, 0.352; 95% CI, 0.151-0.797; P = 0.0122) were associated with a favorable outcome at 90 days in patients with ACS. In patients with BAO, only OTR (OR, 0.9879; 95% CI, 0.974-0.999; P = 0.0314) was associated with a favorable outcome at 90 days.

CONCLUSIONS

MT may be considered the standard care for patients with BAO. OTR was the only common significant predictor for favorable outcomes in both patient cohorts.

Mechanical thrombectomy in basilar artery occlusion: influence of reperfusion on clinical outcome and impact of the first-line strategy (ADAPT vs stent retriever)

OBJECTIVESeveral randomized trials have been focused on patients with anterior circulation stroke, whereas few data on posterior circulation stroke are available. Thus, new mechanical thrombectomy (MT) strategies, including a direct-aspiration first-pass technique (ADAPT), remain to be evaluated in basilar artery occlusion (BAO) patients. The authors here assessed the influence of reperfusion on outcome in BAO patients and examined whether ADAPT improves the reperfusion rate compared with stent retriever devices.METHODSThree comprehensive stroke centers prospectively collected individual data from BAO patients treated with MT. Baseline characteristics as well as radiographic and clinical outcomes were compared between the 2 MT strategies. The primary outcome measure was the rate of successful reperfusion, defined as a modified Thrombolysis in Cerebral Infarction (mTICI) grade of 2b-3. Favorable outcome was defined as a 90-day modified Rankin Scale score of 0-2.RESULTSAmong the 100 adult patients included in the study, 46 were treated with first-line ADAPT (median age 61 years, IQR 53-71 years; stent-retriever rescue therapy was secondarily used in 12 [26.1%]) and 54 were treated with a primary stent retriever (median age 67 years, IQR 53-78 years). There was no difference in baseline characteristics between the 2 treatment groups, except for the rate of diabetes (19.6% vs 5.7%, respectively, p = 0.035). Successful reperfusion was achieved in 79% of the overall study sample. Overall, the rate of favorable outcome was 36.8% and 90-day all-cause mortality was 44.2%. Successful reperfusion positively impacted favorable outcome (OR 4.57, 95% CI 1.24-16.87, p = 0.023). A nonsignificant trend toward a higher successful reperfusion rate (unadjusted OR 2.56, 95% CI 0.90-7.29, p = 0.071) and a significantly higher rate of complete reperfusion (mTICI grade 3; unadjusted OR 2.59, 95% CI 1.14-5.86, p = 0.021) was found in the ADAPT group. The procedure duration was also significantly lower in the ADAPT group (median 45 minutes, IQR 34 to 62 minutes vs 56 minutes, IQR 40 to 90 minutes; p = 0.05), as was the rate of periprocedural complications (4.3% vs 25.9%, p = 0.003). Symptomatic intracranial hemorrhage (0.0% vs 4.0%, p = 0.51) and 90-day all-cause mortality (46.7% vs 42.0%, p = 0.65) were similar in the 2 groups.CONCLUSIONSAmong BAO patients, successful reperfusion is a strong predictor of a 90-day favorable outcome, and the choice of ADAPT as the first-line strategy achieves a significantly higher rate of complete reperfusion with a shorter procedure duration.

Predictive value of the THRIVE score for outcome in patients with acute basilar artery occlusion treated with thrombectomy

BACKGROUND AND PURPOSE

A higher Totaled Health Risks in Vascular Events (THRIVE) score has been shown to predict poor functional outcome in patients with acute ischemic stroke (AIS) and anterior circulation large vessel occlusions undergoing thrombectomy treatment. We attempted to evaluate the value of the THRIVE score in predicting the outcome of thrombectomy treatment in AIS patients with basilar artery occlusion (BAO).

METHODS

A total of 68 AIS patients with BAO who underwent thrombectomy treatment from May 2014 to August 2018 were included in the present study. Multivariable logistic regression was performed to determine the predictive value of the THRIVE score for poor functional outcome (defined as modified Rankin Scale score ≥ 3), all-cause mortality, and hemorrhage transformation (HT) at 3 months.

RESULTS

A total of 42 (61.8%) participants experienced poor functional outcomes, 25 (36.8%) patients died from all causes, and 21 (30.9%) patients had HT during the 3-month follow-up. Multivariable logistic regression showed that a higher THRIVE score was significantly associated with poor functional outcome (odds ratio [OR] 5.86, 95% confidence interval [CI], 2.28-14.91, p < .001) as well as all-cause mortality (OR 2.40, 95% CI, 1.32-4.34, p = .004) but not HT (p = .607). The C-statistic of the THRIVE score was significantly larger than that of the NIHSS score for predicting poor functional outcome (AUC = 0.913; cutoff > 5; sensitivity, 88.5%; specificity, 83.3%, p = .007) and all-cause mortality (AUC = 0.768; cutoff > 5; sensitivity, 92.0%; specificity, 65.1%, p = .018).

CONCLUSIONS

A high THRIVE score was independently associated with an increased risk of poor functional outcome and all-cause mortality in AIS patients with BAO who underwent thrombectomy treatment. Moreover, the THRIVE score appeared to be a better predictor of clinical outcome than the NIHSS score.

Predictors of Outcome After Endovascular Thrombectomy in Acute Basilar Artery Occlusion and the 6hr Time Window to Recanalization

Background and Purpose: Decision algorithms for large vessel occlusions in the anterior circulation remain unconfirmed for acute basilar artery occlusion (aBAO). The aim of this study was to investigate procedural parameters, patient characteristics, functional outcome, and survival in dependency of the time window to recanalization from symptom onset. Furthermore predictors of outcome were identified.

Materials and Methods: Retrospectively 231 patients with aBAO treated with endovascular treatment (EVT) between November 2008 and February 2019 were identified in a prospectively maintained single center stroke database. Baseline characteristics such as age, cardiovascular risk factors, NIHSS at admission, pre-interventional PC-ASPECTS, periprocedural parameters such as time to recanalization, duration of treatment, extent of reperfusion, collateral status, and occlusion patterns, as well as post-interventional 24 h NIHSS and post-interventional ICH were evaluated. Target variables were mRS at 90 days and mortality over 90 days.

Results: Good outcome (mRS 0–2) was attained in 29.5% (n = 68) of patients, overall mortality was 36.8% (n = 85). In mulitivariate analyses patients with time to reperfusion beyond 6 h had a more than half fold decreased chance of good outcome [OR 0.47 95% CI (0.23–0.95) p < 0.05]. The odds for good outcome were reduced by almost 2/3 if post-interventional imaging revealed intracerebral hemorrhage [OR 0.28 95% CI (0.08–0.98)]. Unfavorable outcome was noted in 100% (n = 14) of patients with symptomatic ICH. Risk for death was reduced by more than 80% if collaterals were present [0.16 95% CI (0.03–0.87)] and if recanalization was successful (TICI 2b-3) [OR 0.19 95% CI (0.05–0.78)]. The odds for survival were 5-fold higher in patients with no post-interventional hemorrhages present [OR 5.35 95% CI (2.2–1.58)].

Conclusion: This study might contribute to explaining the ambiguous findings regarding the validity of the 6 h time window in aBAO, suggesting that collateral status impacts the odds of survival in the time window to recanalization beyond 6 h. In our study recanalization within 6 h from symptom onset was associated with good outcome. Successful recanalization (TICI 2b-3a) was necessary for good outcome and survival, post-interventional ICH was highly associated with unfavorable outcome. This might ease the decision making for EVT.

Treatment of posterior circulation strokes by mechanical thrombectomy with a stent-retriever: a retrospective observational study at a single center

OBJECTIVES

To determine the rate of recanalization, functional outcome at three months, and independent prognostic factors in patients with posterior circulation strokes treated with stent-retrievers and to compare these results with those of patients in an earlier series treated with "classical methods".

MATERIAL AND METHODS

This was a retrospective study of consecutive patients with posterior circulation strokes treated with stent-retrievers at our center between December 1, 2011 and May 1, 2018. The main outcome variables were the rate of recanalization according to the Thrombosis in Cerebral Infarction (TICI) scale and functional independence score 90 days after treatment according to the modified Rankin Scale (mRS). We analyzed demographics, cerebrovascular risk factors, clinical findings, and probable origin. Descriptive statistics and a binary logistic regression model were used to analyze the data.

RESULTS

We included 75 patients: 27 treated with "classical methods" and 48 treated with stent-retrievers (10 women; mean age, 63.9 years; median National Institute of Health Stroke Score, 15.8 (IQR 9-25); median Glasgow Coma Scale (GCS), 9.1 (IQR 6-14,5). TICI 2b-3 recanalization was achieved in 46 (95.8%) patients treated with stent-retrievers and in 15 (55.6%) patients treated with "classical methods" (p<0.0001). No significant differences were observed in the rate of patients achieving mRS 0-2 at 90 days (19 (39.6%) of those treated with stent-retrievers vs. 6 (22.2%) of those treated with "classical methods"). Mortality was lower among patients treated with stent-retrievers (14 (29.2% vs. 15 (55.6%) in those treated with "classical methods", p=0.024). GCS score was independently associated with mRS at 90 days (OR:0.67; 95%CI:0.5-0.91; p=0.01).

CONCLUSIONS

In patients with posterior circulation infarcts, treatment with stent-retrievers achieved high rates of recanalization and functional independence at 90 days. The rate of complications was similar to those reported in other studies. GCS is an independent predictor of functional independence at 90 days.

Intracranial mechanical thrombectomy of large vessel occlusions in the posterior circulation using SAVE

Background

Mechanical thrombectomy (MT) using stent retriever assisted vacuum-locked extraction (SAVE) is a promising method for anterior circulation strokes. We present our experience with SAVE for large vessel occlusions (LVO) of the posterior circulation.

Methods

We retrospectively analyzed 66 consecutive MT patients suffering from LVO of the posterior circulation. Primary endpoints were first-pass and overall complete/near complete reperfusion, defined as a modified thrombolysis in cerebral infarction (mTICI) score of 2c and 3. Secondary endpoints contained number of passes, time interval from groin puncture to reperfusion and rate of postinterventional symptomatic intracranial hemorrhage (sICH).

Results

Median age was 75 years (interquartile range (IQR) 54–81 years). Baseline median National Institutes of Health stroke scale (NIHSS) was 13 (IQR 8–21). Fifty-five (83%) patients had LVO of the basilar artery and 11 (17%) of the posterior cerebral artery. Eighteen (27%) patients were treated with SAVE and 21 (32%) with aspiration only. First pass mTICI2c or 3 and overall mTICI2c or 3 were documented in 11/18 (61%) and 14/18 (78%) with SAVE and in 4/21 (19%) and 13/21 (33%) with aspiration only. Median attempt was 1 (IQR 1–2) with SAVE and 2 (IQR 1–4) with aspiration (p = 0.0249). Median groin to reperfusion time did not differ significantly between groups. The rate of sICH was 5% without any complications in the SAVE cohort.

Conclusion

Mechanical thrombectomy of posterior large vessel occlusions with SAVE is feasible, safe, and effective with high rates of near-complete and complete reperfusion.

Mechanical thrombectomy for basilar artery occlusion: efficacy, outcomes, and futile recanalization in comparison with the anterior circulation

BACKGROUND

Performing mechanical thrombectomy (MT) in patients with basilar artery occlusion (BAO) is currently not evidence-based.

OBJECTIVE

To compare patients' outcome, relative merits of achieving recanalization, and predictors of futile recanalization (FR) between BAO and anterior circulation large vessel occlusion (ACLVO) MT.

METHODS

In the multicenter BEYOND-SWIFT registry (NCT03496064), univariate and multivariate (displayed as adjusted Odds Ratios, aOR and 95% confidence intervals, 95%-CI) outcome comparisons between BAO (N=165) and ACLVO (N=1574) were performed. The primary outcome was favorable outcome at 90 days (modified Rankin Scale, mRS 0-2). Secondary outcome included mortality, symptomatic intracranial hemorrhage (sICH) and FR. The relative merits of achieving successful recanalization between ACLVO and BAO were evaluated with interaction terms.

RESULTS

MT in BAO was more often technically effective and equally safe in regards to mortality and sICH when compared to ACLVO. When adjusting for baseline differences, there was no significant difference between BAO vs ACLVO regarding rates of favorable outcome (aOR 0.986, 95%-CI 0.553 - 1.758). However, BAO were associated with increased rates of FR (aOR 2.146, 95%-CI 1.267 - 3.633). Predictors for FR were age, stroke severity, maneuver count and intracranial stenting. No significant heterogeneity on the relative merits of achieving successful recanalization on several outcome parameters were observed when comparing BAO and ACLVO.

CONCLUSIONS

In selected patients, similar outcomes can be achieved in BAO and ACLVO patients treated with MT. Randomized controlled trials comparing patient selection and interventional strategies seem warranted to avoid FR.

TRIAL REGISTRATION NUMBER

NCT03496064.

Stent Retriever Thrombectomy Potentially Increases the Recanalization Rate, Improves Clinical Outcome, and Decreases Mortality in Acute Basilar Occlusion: A Systematic Review and Meta-Analysis

BACKGROUND

Acute basilar artery occlusion (BAO) is a devastating condition if untreated. The optimal treatment strategy, however, is unknown. Historically, interventional approaches have been favored over intravenous thrombolysis (IVT), although this is not supported by good evidence. The aim of this systematic review and meta-analysis was to summarize and compare the results for treatment modalities of BAO, namely, IVT and interventional stent retriever thrombectomy (SRT).

METHODS

Studies on IVT and SRT in BAO were systematically searched. Successful recanalization (TICI ≥2b), favorable clinical outcome (modified Rankin Scale score ≤2), mortality, and the rate of symptomatic intracranial hemorrhage (SICH) were the target parameters. Only studies with ≥15 patients were included. IVT prior to SRT was allowed. Studies were excluded (1) if >1 thrombectomy device was used in >50% of the patients and (2) when data on outcome or treatment could not be parsed (e.g. registries). Odds ratios (ORs) were calculated using Mantel-Haenszel risk ratio estimation. Results are given as OR and the 95% confidence interval (95% CI). The χ2 test was used to compare the outcome parameters clinical outcome, recanalization, mortality, and SICH.

RESULTS

A total of 17 studies (4 on IVT and 13 on SRT) with a total of 672 patients (IVT, n = 314; SRT, n = 358) were identified. Cumulatively, we found a highly significantly improved clinical outcome (43 vs. 31%, p = 0.004, OR [95% CI] = 1.66 [1.21, 2.76]), increased recanalization rate (88 vs. 60%, p < 0.00001, OR [95% CI] = 3.99 [2.73, 5.84]), and decreased mortality (26 vs. 41%, p = 0.0004, OR [95% CI] = 1.86 [1.33, 2.61]), as well as an equal rate of SICH (5 vs. 7%, p = 0.15, OR [95% CI] = 1.68 [0.82, 3.43]), in patients treated with SRT compared to those treated with IVT alone.

CONCLUSIONS

The data from this meta-analysis suggest a possible superiority of SRT over IVT, pending positive results of randomized controlled trials. According to international recommendations, patients with BAO should preferentially be treated with SRT; if no contraindications exist, IVT should not be withheld.

Posterior circulation ischemic stroke-a review part II: imaging and acute treatment

Posterior circulation strokes affect the vertebrobasilar arterial system, account for about 20-25% of all ischemic strokes, and are a significant cause of patient disability and mortality. Diagnosis can be challenging; clinical presentation and common pitfalls facing posterior circulation stroke have been discussed elsewhere. In the first part of the review, we focus on the imaging, discussing the information that can be gathered through a correct selection and interpretation of different possible studies helping to achieve an early diagnosis and to select the best medical treatment. In the second part of the review, we will discuss the best therapeutic treatments available at the moment for posterior circulation ischemia.

Endovascular treatment of tandem occlusions in vertebrobasilar stroke: technical aspects and outcome compared with isolated basilar artery occlusion

Background and purpose

Acute basilar artery occlusion (BAO) is a devastating disease with a high rate of mortality and morbidity, and early recanalization is crucial to achieve a good prognosis. The best treatment strategy for BAO combined with a proximal stenosis (tandem occlusion) is not yet clear. Our study aimed to evaluate whether and how vertebrobasilar tandem occlusions can be treated effectively and safely compared with isolated BAO.

Materials and methods

Fifty-two patients with acute vertebrobasilar occlusive stroke treated with mechanical thrombectomy were identified in a prospective database from March 2010 to September 2016. We retrospectively analysed the clinical, technical, and functional outcomes of the patients.

Results

Of the 52 patients, 15 presented with a tandem occlusion, 14 with a single intracranial occlusion due to an underlying stenosis, and 23 with a single embolic BAO. Successful recanalization was achieved in all of the patients with tandem occlusions (modified Thrombolysis in Cranial Infarction 2b/3) and in 35 of 37 patients with a single BAO (with and without stenosis). A favourable outcome was achieved (modified Rankin Scale ≤2) in 8 of the 15 patients with a tandem occlusion compared with 4 of the 14 patients with a single BAO with underlying stenosis and 5 of the 23 patients with isolated embolic BAO (p=0.18).

Conclusions

We suggest that endovascular treatment of vertebrobasilar tandem occlusions is safe and feasible, with a high rate of good outcome.

Conveniently-Grasped Field Assessment Stroke Triage (CG-FAST): A Modified Scale to Detect Large Vessel Occlusion Stroke

Background and Purpose: Patients with large vessel occlusion stroke (LVOS) need to be rapidly identified and transferred to comprehensive stroke centers (CSC). However, previous pre-hospital strategy remains challenging. We aimed to develop a modified scale to better predict LVOS.

Methods: We retrospectively reviewed our prospectively collected database for acute ischemic stroke (AIS) patients who underwent CT angiography (CTA) or time of flight MR angiography (TOF-MRA) and had a detailed National Institutes of Health Stroke Scale (NIHSS) score at admission. Large vessel occlusion (LVO) was defined as the complete occlusion of large vessels, including the intracranial internal carotid artery (ICA), M1, and M2 segments of the middle cerebral artery (MCA), and basilar artery (BA). The Conveniently-Grasped Field Assessment Stroke Triage (CG-FAST) scale consisted of Level of Consciousness (LOC) questions, Gaze deviation, Facial palsy, Arm weakness, and Speech changes. Receiver Operating Characteristic (ROC) analysis was used to obtain the Area Under the Curve (AUC) of CG-FAST and previously established pre-hospital prediction scales.

Results: Finally, 1,355 patients were included in the analysis. LVOS was detected in 664 (49.0%) patients. The sensitivity, specificity, positive predictive value, and negative predictive value of CG-FAST were 0.617, 0.810, 0.785, and 0.692 respectively, at the optimal cutoff (≥4). The AUC, Youden index and accuracy of the CG-FAST scale (0.758, 0.428, and 0.728) were all higher than other pre-hospital prediction scales.

Conclusions: CG-FAST scale could be an effective and simple scale for accurate identification of LVOS among AIS patients.

Mechanical Thrombectomy in Subtypes of Basilar Artery Occlusion: Relationship to Recanalization Rate and Clinical Outcome

Background Acute stroke because of basilar artery occlusion (BAO) represents 1% of all ischemic strokes. However, recanalization rates and treatment outcome for the different pathologic subtypes of BAO stroke are not fully understood. Purpose To compare the recanalization rate and clinical outcomes of mechanical thrombectomy in different subtypes of BAO. Materials and Methods Eighty-two patients (46 men and 36 women; mean age, 73 years; age range, 20-90 years; mean age in men, 70 years [age range, 20-90 years]; mean age in women, 75 years [age range; 61-90 years]) with acute BAO who underwent mechanical thrombectomy between March 2010 and December 2017 were retrospectively analyzed. Patients were classified into three groups: embolism without vertebral artery (VA) steno-occlusion (group 1), embolism from tandem VA steno-occlusion (group 2), and in situ atherosclerotic thrombosis (group 3). Clinical and angiographic characteristics, recanalization rate, procedure times, and clinical outcomes were compared between groups by using the Kruskal-Wallis, Pearson χ², and Fisher exact tests. Results The incidence of BAO according to stroke mechanism were as follows: group 1, n = 34 (41%); group 2, n = 28 (34%), group 3, n = 20 (24%). Overall, successful recanalization (modified Thrombolysis in Cerebral Infarction grade 2b or 3) was achieved in 78% (64 of 82) and favorable outcome (90-day modified Rankin Scale score, 0-2) in 37% (30 of 82) of the patients. The procedure time was shorter in group 1 than in group 2 (49 vs 66 minutes, respectively; P = .01). Group 1 showed a higher successful recanalization rate than group 3 (29 of 34 [85%] vs 11 of 20 [55%], respectively; P = .01). Good clinical outcome rate was higher in group 1 than in group 3 (18 of 34 [53%] vs four of 20 [20%], respectively; P = .02). Conclusion The outcome of mechanical thrombectomy for basilar artery occlusion differs according to the pathologic mechanism of stroke; the best outcomes and recanalization rate occurred in patients with embolism without vertebral artery steno-occlusion. © RSNA, 2019 See also the editorial by Hetts in this issue.

Firstline a direct aspiration first pass technique versus firstline stent retriever for acute basilar artery occlusion: a systematic review and meta-analysis

INTRODUCTION

Acute basilar artery occlusion (BAO) can result in extremely high disability and mortality. Stent retrievers (SRs) can achieve a high recanalization rate for BAO, therefore improving favorable outcomes. However, the efficacy of a direct aspiration first pass technique (ADAPT) to treat BAO is unclear. Our aim was to compare the efficacy and safety of firstline ADAPT with that of firstline SR for patients with acute BAO.

METHODS

Three databases were systematically searched for literature reporting outcomes on thrombectomy for acute BAO with both firstline ADAPT and firstline SR. The modified Newcastle-Ottawa scale was applied to assess bias risk. The random effects model was used.

RESULTS

Of 50 articles, 5 cohort studies (2 prospective and 3 retrospective) were included in our research. 193 cases were treated with firstline ADAPT and 283 cases received firstline SR. Successful recanalization rate was significantly higher in the firstline ADAPT group (OR=2.0, 95% CI 1.1 to 3.5). Procedure time (mean difference=-27.6 min, 95% CI -51.0 to -4.3) and the incidence of new territory embolic event (OR=0.2, 95% CI 0.05 to 0.83) was significantly less in the firstline ADAPT group. No significant difference was observed between the firstline ADAPT and firstline SR groups for rate of complete recanalization, rescue therapy, any hemorrhagic complication, favorable outcomes, or mortality at 90 days.

CONCLUSIONS

Our meta-analysis suggested that for patients with acute BAO, firstline ADAPT might achieve higher and faster recanalization, comparable neurological improvement and safety compared with firstline SR. Further studies are needed to confirm these results.

Endovascular Treatment of Atherosclerotic Tandem Occlusions in Anterior Circulation Stroke: Technical Aspects and Complications Compared to Isolated Intracranial Occlusions

Background and Purpose: Endovascular treatment of tandem occlusions is an emerging option. We describe our multicenter experience with endovascular management of atherosclerotic tandem occlusions in the anterior circulation, particularly the technical aspects and complications in comparison to isolated intracranial occlusions.

Materials and Methods: Consecutive patients with tandem occlusions due to atherosclerotic causes who underwent mechanical thrombectomy at two major stroke centers between January 2010 and September 2015 were reviewed. Clinical data, procedural aspects, recanalization rates, complication rates, and clinical outcome were analyzed and compared to findings in patients with isolated intracranial occlusions.

Results: One hundred and twenty-one patients with tandem occlusions and 456 patients with isolated intracranial occlusions (carotid-T/M1) were included. Mean intervention time was faster (33 min vs. 57 min, p < 0.001) and recanalization success was higher (TICI 2b/3 83.6 vs. 70.2%, p = 0.002) in patients with isolated occlusions. No difference was seen in clinical outcome and complications, except for a higher rate of asymptomatic hemorrhage in the tandem group (29.8 vs. 17.1%, p = 0.003). Choice of recanalization approach (antegrade vs. retrograde) in the tandem group made no difference, except for a trend toward less distal emboli using the retrograde approach (4.0 vs. 13.0%, p = 0.082). Stenting of the extracranial internal carotid artery (ICA) was performed in 81%, PTA alone in 7.4%, and deferred stenting in 11.6%. Rate of stent/ICA occlusion within 7 days was 10.3% after stenting and 33.3% after PTA (p = 0.127). In the tandem group, age (p = 0.034), National Institutes of Health Stroke Scale score (NIHSS) at admission (p = 0.002), recanalization rate (p < 0.001), complications (p = 0.016), and symptomatic intracranial hemorrhage (sICH) (p = 0.001) were associated with poor outcome, whereas extracranial treatment modality and stent/ICA occlusion within 7 days did not affect outcome.

Conclusion: Endovascular treatment of tandem occlusions is technically feasible, achieves recanalization rates and rates of good clinical outcome comparable to those in patients with isolated intracranial occlusions. Following acute ICA stenting, the risk of stent occlusion and sICH appeared to be low, but was associated with an increased rate of asymptomatic ICH.

A direct aspiration first pass technique with the new ARC catheter for thrombectomy of large vessel occlusion strokes: A multicenter study

BACKGROUND AND PURPOSE

A direct aspiration first pass technique involves first-line aspiration to remove the thrombus through a large-bore aspiration catheter in large vessel strokes. The aim of this study was to assess safety and clinical outcomes with a direct aspiration first pass technique using the new ARC catheter.

METHODS

A retrospective analysis of prospectively collected data from three university hospitals was performed between June 2016 and May 2018. The following parameters of all acute ischemic stroke interventions using the ARC catheter were analyzed: use of intravenous thrombolysis, National Institutes of Health Stroke Scale scores at presentation and discharge, successful reperfusion (modified Thrombolysis in Cerebral Infarction 2b-3), procedure duration, procedure-related complications and 90-day clinical outcome (modified Rankin Scale score).

RESULTS

In total, 41 patients were included in the study and anterior circulation occlusion was noted in 35 (85%). The median National Institutes of Health Stroke Scale at admission was 18 and prior intravenous thrombolysis was administered in 35 patients (85%). Only six (15%) patients required the use of a rescue stent retriever. Successful reperfusion was achieved in 40 patients (98%) with a median procedure time of 32 minutes. No catheter-related complications were observed. Symptomatic intracerebral hemorrhage occurred in one patient (2%). Median National Institutes of Health Stroke Scale at discharge was 3; 49% were independent and 10% died at 90 days.

CONCLUSIONS

In the present study, the ARC catheter allowed a 98% successful reperfusion rate. The complication rate was in line with those of previous a direct aspiration first pass technique publications.

Thrombectomy for Acute Ischemic Stroke: Recent Insights and Future Directions

PURPOSE OF REVIEW

Mechanical thrombectomy has become the standard of care for acute ischemic stroke with proximal large vessel occlusions (LVO). This article reviews recent research relating to thrombectomy.

RECENT FINDINGS

Thrombectomy for anterior circulation stroke with proximal LVO was first shown to be highly efficacious within 6 h of stroke onset, but "late-window" trials have further demonstrated efficacy until 24-h postonset in select patients with salvageable tissue. However, the concept of "time is brain" remains critical. Thrombectomy trials have further stimulated worldwide efforts to develop systems of care for rapid treatment of eligible patients. Thrombectomy is cost-effective and likely to have long-term efficacy for both disability and mortality outcomes. Thrombectomy is a highly efficacious acute stroke therapy. Enduring uncertainties include efficacy in patients with premorbid disability, posterior circulation, or more distal occlusions; use of bridging thrombolysis; and optimal techniques to achieve consistent revascularization and address tandem occlusions or stenoses.

Endovascular Thrombectomy for Acute Basilar Artery Occlusion: A Multicenter Retrospective Observational Study

Background

Despite the recent acceptance of thrombectomy as the standard of care in patients with acute anterior circulation stroke, the benefits of thrombectomy remain uncertain for patients with acute basilar artery occlusion (BAO). This study aimed to evaluate the effectiveness and safety of thrombectomy and to identify predictors of outcomes in a large cohort of patients with acute BAO.

Methods and Results

This study included 212 consecutive patients with acute BAO who underwent either stent‐retriever or contact aspiration thrombectomy as the first‐line approach between January 2011 and August 2017 at 3 stroke centers. Clinical and radiologic data were prospectively collected and stored in a database at each center. Multivariable ordinal logistic regression was performed to assess the association between each characteristic and 90‐day modified Rankin scale scores. Reperfusion was successful in 91.5% (194/212) of patients; 44.8% (95/212) of patients achieved 90‐day modified Rankin scale 0 to 2. The symptomatic hemorrhage rate was 1.9% (4/212) and mortality was 16% (34/212). In a multivariable ordinal regression, younger age, lower National Institute of Health stroke scale on admission, and absence of diabetes mellitus and parenchymal hematoma were significantly associated with a favorable shift in the overall distribution of 90‐day modified Rankin scale scores. Treatment outcomes were similar between patients who received stent‐retriever thrombectomy and contact aspiration thrombectomy as the first‐line technique.

Conclusions

Endovascular thrombectomy was effective and safe for treating patients with acute BAO. Age, the baseline National Institute of Health stroke scale, diabetes mellitus, and parenchymal hematoma were associated with better outcomes. This study showed no superiority of the stent‐retriever over the aspiration thrombectomy for treating acute BAO.

A review of the diagnosis and management of vertebral basilar (posterior) circulation disease

We have reviewed the English literature published in the last 70 years on Diseases of the Vertebral Basilar Circulation, or Posterior Circulation Disease (PCD). We have found that errors have been made in the conduct and interpretation of these studies that have led to incorrect approaches to the management of PCD. Because of the difficulty in evaluating the PC, the management of PCD has been incorrectly applied from anterior circulation disease (ACD) experience to PCD. PCD is a common form of stroke affecting 20-40% patients with stroke. Yet, the evidence is strong that the Anterior Circulation (AC) and Posterior Circulations (PC) differ in their pathology, in their clinical presentations, in the rapidity of development of symptoms, in optimal imaging methods, and in available treatments. There appears to be two categories of patients who present with PCD. The first, acute basilar artery occlusion has a more rapid onset. The diagnosis must be made quickly and if imaging proves a diagnosis of Basilar Artery Occlusion (BAO), the treatment of choice is Interventional removal of the basilar artery thrombosis or embolus. The second category of PCD and the most commonly seen PCD disease process presents with non-specific symptoms and early warnings of PCD that now can be related to ischemic events in the entire PC vessels. These warning symptoms and signs occur much earlier than those in the AC. IA angiography is still the gold standard of diagnosis and is superior in definition to MR and CT angiography which are commonly used as a convenient screening imaging tool to evaluate PCD but are both inferior to IA angiography in definition for lesions below 3-4 mm. In at least two reported studies 7T MR angiography appears superior to other imaging modalities and will become the gold standard of imaging of PCD in the future. Medical treatments applied to the ACD have not been proven of value in specific forms of PCD. Interventional therapy was promising but of unproven value in Randomized Controlled Trials (RCT) except for the treatment of Basilar Artery Occlusion (BAO). Surgical revascularization has been proved to be highly successful in patients, who are refractory to medical therapy. These studies have been ignored by the scientific community basically because of an incorrect interpretation of the flawed EC-IC Bypass Trial in 1985 as applying to all stroke patients. Moreover, the EC-IC Bypass Study did not include PCD patients in their study population, but the study results were extrapolated to patients with PCD without any scientific basis. This experience led clinicians to an incorrect bias that surgical treatments are of no value in PCD. Thus, incorrectly, surgical treatments of PCD have not been considered among the therapeutic possibilities for PCD. QMRA is a new quantitative MR technique that measures specific blood flow in extra and intracranial vessels. QMRA has been used to select those patients who may benefit from medical, or interventional, or surgical treatment for PCD based on flow determinations with a high success rate. QMRA accurately predicts the flows in many large and small vessels in the PC and AC and clearly indicates that both circulations are intimately related. From medical and surgical studies, the longer one waits for surgical treatment the higher the risk of a poor outcome results. This observation becomes obvious when the rapidity of development of PCD is compared with ACD. Recent advances in endovascular therapy in the treatment of acute basilar thrombosis is a clear sign that early diagnosis and treatment of PCD will reduce the morbidity and mortality of these diseases. In this review it is evident that there are multiple medical and surgical treatments for PCD depending upon the location of the lesion(s) and the collateral circulation demonstrated. It is clear that the AC and PC have significant differences. With the exception of the large population studies from Oxford England, the reported studies on the management of PCD in the literature represent small selected subsets of the universe of PC diseases, the information from which is not generalizable to the universe of PCD patients. At this point in the history of PCD, there are not large enough databases of similar patients to provide a basis for valid randomized studies, with the exception of the surgical studies. Thus, a high index of suspicion of the early warning symptoms of PCD should lead to a rapid individual clinical assessment of patients selecting those with PCD. Medical, interventional, and/or surgical treatments should be chosen based on knowledge presented in this review. Recording the results in a national Registry on a continuing basis will provide the data that may help advance the management of PCD based on larger data bases of well documented patient information to guide the selection of future therapies for PCD treatments. It is also clear that the management of patients within the complex of diseases that comprise PCD should be performed in centers with expertise in the imaging, medical, interventional and surgical approaches to diseases of the PCD.

A direct aspiration first pass technique for acute stroke therapy: a systematic review and meta-analysis

BACKGROUND AND PURPOSE

A direct aspiration first pass technique (ADAPT), involving the first-line use of a large-bore distal aspiration catheter, is a new strategy in the mechanical thrombectomy of acute ischemic stroke caused by large-vessel occlusion. However, its impact on reperfusion rates, clinical outcomes and complication rates has not been fully examined.

METHODS

We conducted a systematic review of the literature searching multiple databases for reports on thrombectomy of acute stroke with ADAPT and performed meta-analyses of clinical and radiographic outcomes.

RESULTS

We selected 16 articles that included a total of 1378 patients treated with ADAPT. The mean admission National Institutes of Health Stroke Scale score was 17 and pre-treatment intravenous thrombolysis was used in 51% of cases. The successful recanalization (thrombolysis in cerebral ischemia 2b-3) rate was 66% [95% confidence interval (CI), 59-72%] with ADAPT and a rescue stent retriever was used in 31% of cases (95% CI, 24-37%) yielding an overall thrombolysis in cerebral ischemia 2b-3 rate of 89% (95% CI, 85-92%). We found a pooled estimate of 50% (95% CI, 45-54%) for functional independence (modified Rankin Scale score 0-2) at 90 days, 15% (95% CI, 10-21%) for mortality within 90 days and 5% (95% CI, 3-7%) for symptomatic intracranial hemorrhage.

CONCLUSIONS

ADAPT therapy is associated with similar reperfusion rates, clinical outcomes and complication rates compared with thrombectomy with stent retrievers. However, the major limitations of current evidence (i.e. retrospective studies and selection bias) indicate a need for adequately powered, multicenter randomized controlled trials to determine the best strategy.

Predictors for Mortality after Mechanical Thrombectomy of Acute Basilar Artery Occlusion

Background: Modern endovascular thrombectomy (MET), using stent retrievers or large-bore distal aspiration catheters in stroke patients with acute basilar artery occlusion (BAO), is routinely performed to date. However, more than 35% of BAO patients treated with MET die within 90 days despite high recanalization rates. The purpose of this study is to investigate the parameters associated with 90-day mortality in patients with BAO after MET. Methods: We analyzed 117 consecutive BAO patients included in the Endovascular Treatment in Ischemic Stroke prospective clinical registry of consecutive acute ischemic stroke patients treated with MET (60 patients [51.3%] treated with a stent retriever as first-line technique) between March 2010 and April 2017. Successful recanalization was defined as modified thrombolysis In cerebral infarction scores 2b-3 at the end of MET, and mortality was defined as modified Rankin Scale 6 at 90 days. Associations of baseline characteristics (patient and treatment characteristics) and intermediate outcomes (recanalization, complications) with 90-day mortality were investigated in univariate and multivariate analyses. Results: Overall successful recanalization rate was 79.5, and 41.9% (95% CI 32.8–51.0%) of patients died within 90 days after MET. Patients with successful recanalization had a lower mortality rate (32.9 vs. 74.4%; p < 0.001). Failure of successful recanalization was an independent predictor of mortality (OR 5.1; 95% CI 1.34–19.33). In multivariate analysis, age ≥60 years (OR 6.37; 95% CI 1.74–23.31), admission National Institute of Health Stroke Scale (NIHSS) ≥13 (OR 4.62; 95% CI 1.42–15.03), lower posterior circulation-Alberta Stroke Program Early CT Score (pc-ASPECTS; OR 1.71; 95% CI 1.19–2.44), use of antithrombotic medication prior to stroke onset (OR 3.38; 95% CI 1.03–11.08), absence of intravenous thrombolysis (OR 3.36; 95% CI 1.12–10.03), and angioplasty/stenting of the basilar artery (OR 4.71; 95% CI 1.34–16.54) were independent predictors for mortality after MET. Conclusions: Failure of successful recanalization was a strong predictor for mortality. In the setting of recanalization, age, admission NIHSS, pc-ASPECTS, absence of intravenous thrombolysis, and angioplasty/stenting of the basilar artery were also independent predictors for mortality after MET of BAO patients.