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

Predicting clinical outcome in posterior circulation large-vessel occlusion patients with endovascular recanalisation: the GNC score

BACKGROUND AND PURPOSE

Acute ischaemic strokes caused by posterior circulation large-vessel occlusions (pc-LVOs) are associated with particularly poor prognoses, including significant disability and mortality rates. This study sought to develop and validate a novel scoring system for predicting functional outcomes in pc-LVO cases following successful endovascular recanalisation.

METHODS

We derived a predictive model from the DETECT-China cohort and externally validated it using the DETECT2-China dataset. Poor outcome was defined as a modified Rankin Scale score of 4-6 at 90 days. Cerebral circulation time (CCT), measured via digital subtraction angiography (DSA), served as a key predictor. Multivariable logistic regression was employed to construct the scoring system.

RESULTS

The training cohort comprised 92 patients, of whom 52 (56.5%) experienced poor outcomes. Multivariate analysis identified prolonged CCT (adjusted OR (aOR) 1.365; 95% CI 1.105 to 1.686; p=0.004), elevated admission National Institutes of Health Stroke Scale (NIHSS) (aOR 1.235; 95% CI 1.120 to 1.363; p<0.001) and higher blood glucose levels (aOR 1.345; 95% CI 1.023 to 1.769; p=0.034) as independent predictors. These variables were integrated into the GNC score (Glucose-NIHSS-CCT). The GNC score demonstrated excellent predictive performance for clinical outcome, good discrimination and calibration in this cohort, as well as the bootstrap validation. Importantly, the excellent performance of this score was further validated in DETECT2-China.

CONCLUSIONS

This is the first report that CCT based on DSA is an independent prognostic marker in pc-LVO patients with successful recanalisation post-endovascular treatment. The GNC score, incorporating readily available clinical and angiographic parameters, offers a reliable tool for outcome prediction in this high-risk population.

Retrograde recanalization for vertebral artery occlusion without a stump (REVANS): a technical note

Recent case reports suggest that endovascular recanalization may be safe and feasible for vertebral artery occlusion (VAO) patients without a stump, however, comprehensive management strategies for endovascular recanalization remain poorly understood. In this technical note, we describe the REVANS technique in patients with VAO lacking a stump. The REVANS technique demonstrates promise as a viable option for managing symptomatic non-acute VAO without a visible stump. This approach leverages cervical collateral vessels to retrogradely access and recanalize occluded vertebral artery segments, offering potential benefits in improving patient outcomes.

Predictors and outcomes of first pass efficacy in posterior circulation strokes: Insights from STAR collaboration

Background: First-pass efficacy (FPE) has been established as an important predictor of favorable functional outcomes after endovascular thrombectomy (ET) in anterior circulation strokes. In this retrospective cohort study, we investigate predictors and clinical outcomes of FPE in posterior circulation strokes (pcAIS). Methods: The Stroke Thrombectomy and Aneurysm Registry database was used to identify pcAIS patients who achieved FPE. Their baseline characteristics and outcomes were compared with the non-FPE group. The primary outcome was a 90-day modified Rankin Scale (mRS) of 0-3. Univariate (UVA) and multivariate (MVA) analyses were done to evaluate predictors of FPE. Safety outcomes included distal emboli, vessel rupture, symptomatic intracranial hemorrhage, and mortality. Results: Of 359 patients, 179 (50%) achieved FPE. Clot burden, occlusion site, and ET technique-related variables were similar between the two groups except for shorter procedure time with FPE. The primary outcome was significantly better with FPE (56.4% vs. 32.8%, p < 0.001). Complications were similar except for a higher rate of distal emboli in non-FPE group (11.1% vs. 3.2%, p = 0.032). Atrial fibrillation (Afib) had increased odds (aOR: 2.06, 95% CI; 1.24, 3.4, p = 0.005) and prior ischemic stroke had decreased odds (aOR: 0.524, 95% CI; 0.28, 0.97, p = 0.04) of FPE. Afib was the only independent predictor of FPE on MVA (1.94, 95% CI; 1.1, 3.43, p = 0.022). Conclusions: Higher rate of FPE in Afib-related pcAIS could possibly be explained by the differences in clot composition and degree of in-situ atherosclerotic disease burden. Future studies are warranted to explore the relationship of clot composition with ET outcomes.

The role of first pass effect in mechanical thrombectomy for vertebrobasilar artery occlusion: a comprehensive meta-analysis of prevalence, outcomes, and predictive factors

BACKGROUND

First-pass effect (FPE) is crucial for better outcomes in mechanical thrombectomy (MT) for acute large vessel occlusions. However, its frequency and predictors in vertebrobasilar artery occlusion (VBAO) remain unclear.

OBJECTIVE

To conduct a comprehensive systematic review and meta-analysis to assess the incidence of FPE in MT for VBAO and its impact on key clinical outcomes. Additionally, to explore potential predictors of achieving FPE, addressing critical knowledge gaps and providing evidence to optimize treatment strategies for patients with VBAO.

METHODS

A systematic literature search was performed in PubMed, EMBASE, Web of Science, and the Cochrane Library up to November 1, 2024. Studies evaluating FPE in patients with acute VBAO undergoing MT were included. The prevalence of FPE was estimated using a meta-analysis of proportions, and associations with clinical outcomes and predictive factors were assessed using pooled ORs with random-effects models.

RESULTS

Twenty studies involving 4315 patients met inclusion criteria. The overall prevalence of FPE in patients with VBAO was 41% (95% CI 33% to 50%). FPE was significantly associated with improved 90-day outcomes (modified Rankin Scale (mRS) score 0-2: OR=2.00, 95% CI 1.45 to 2.75; mRS score 0-3: OR=2.33, 95% CI 1.78 to 3.04), reduced risk of symptomatic intracranial hemorrhage (OR=0.49, 95% CI 0.27 to 0.87), and lower mortality (OR=0.43, 95% CI 0.32 to 0.57). The results showed that significant positive predictors of FPE included female sex, atrial fibrillation, cardioembolic or unknown stroke etiology, mid- or distal basilar artery occlusion, contact aspiration techniques, and the use of larger catheters. Conversely, negative predictors were identified as a history of hypertension, hyperlipidemia, prior stroke or transient ischemic attack, higher baseline NIHSS scores, prolonged procedure time, and the use of general anesthesia.

CONCLUSION

Achieving FPE in acute VBAO is strongly associated with improved clinical outcomes. Important clinical, procedural, and anatomical factors related to FPE were identified, aiding clinical decisions and thrombectomy techniques.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

A Deep Learning Approach to Predict Recanalization First-Pass Effect following Mechanical Thrombectomy in Patients with Acute Ischemic Stroke

BACKGROUND AND PURPOSE

Following endovascular thrombectomy in patients with large-vessel occlusion stroke, successful recanalization from 1 attempt, known as the first-pass effect, has correlated favorably with long-term outcomes. Pretreatment imaging may contain information that can be used to predict the first-pass effect. Recently, applications of machine learning models have shown promising results in predicting recanalization outcomes, albeit requiring manual segmentation. In this study, we sought to construct completely automated methods using deep learning to predict the first-pass effect from pretreatment CT and MR imaging.

MATERIALS AND METHODS

Our models were developed and evaluated using a cohort of 326 patients who underwent endovascular thrombectomy at UCLA Ronald Reagan Medical Center from 2014 to 2021. We designed a hybrid transformer model with nonlocal and cross-attention modules to predict the first-pass effect on MR imaging and CT series.

RESULTS

The proposed method achieved a mean 0.8506 (SD, 0.0712) for cross-validation receiver operating characteristic area under the curve (ROC-AUC) on MR imaging and 0.8719 (SD, 0.0831) for cross-validation ROC-AUC on CT. When evaluated on the prospective test sets, our proposed model achieved a mean ROC-AUC of 0.7967 (SD, 0.0335) with a mean sensitivity of 0.7286 (SD, 0.1849) and specificity of 0.8462 (SD, 0.1216) for MR imaging and a mean ROC-AUC of 0.8051 (SD, 0.0377) with a mean sensitivity of 0.8615 (SD, 0.1131) and specificity 0.7500 (SD, 0.1054) for CT, respectively, representing the first classification of the first-pass effect from MR imaging alone and the first automated first-pass effect classification method in CT.

CONCLUSIONS

Results illustrate that both nonperfusion MR imaging and CT from admission contain signals that can predict a successful first-pass effect following endovascular thrombectomy using our deep learning methods without requiring time-intensive manual segmentation.

Endovascular Thrombectomy for Acute Ischemic Stroke : Current Concept in Management

Endovascular thrombectomy (EVT) has been established as the standard of care in the treatment of acute ischemic stroke (AIS) based on landmark randomized controlled trials. Nevertheless, while the strict eligibility of EVT for AIS patients restrict the wide application of EVT, a considerable population still undergoes off-label EVT. Besides, it is important to acknowledge that recanalization is not achieved in approximately 20% of procedures, and more than 50% of patients who undergo EVT still do not experience a favorable outcome. This article reviews the brief history of EVT trials and recent progressions in the treatment of AIS, with focusing on the expanding eligibility criteria, new target for EVT, and the evolution of EVT techniques.

Long-term outcomes among ischemic stroke TOAST subtypes: A 12-year Cohort study in China

BACKGROUND

Disparities in short-term ischemic stroke (IS) prognosis among Trial of Org 10172 in Acute Stroke Treatment (TOAST) subtypes were observed. Notably, little is known about the long-term prognosis of different subtypes in China. We aim to investigate the long-term outcome in IS patients and try to explore the potential interactive effects between IS subtypes and antithrombotic therapy.

METHODS

This is a prospective cohort of stroke survivors. Patients diagnosed with first-ever IS at the Department of Neurology, West China Hospital, Sichuan University from January 2010 to December 2019 were recruited. They were followed until September 2022 to assess recurrence, mortality, and functional recovery. The multivariate Fine-Gray model assessed stroke recurrence, while Cox regression estimated hazard ratios. Modified Rankin Scale scores(mRS) were analyzed using the generalized linear mixed effects model.

RESULTS

At baseline, 589 of 950 participants (62.00 %) were male. The longest follow-up was 150 months, the shortest was 1.5 months, and the median follow-up was 81.0 months. Cardio-embolism (CE) bore the highest mortality risk compared to large artery atherosclerosis (LAA) (HR=4.43,95 %CI 1.61-12.23). Among survivors on anticoagulant therapy, CE exhibited a reduced risk of mortality (HR = 0.18, 95 % CI 0.04-0.80). In function recovery, small artery occlusion (SAO) demonstrated more favorable prognostic outcomes (β=-2.08, P<0.01, OR=0.13,95 %CI 0.03-0.47). Among survivors taking antiplatelet drugs, SAO demonstrated a slower pace of functional recovery compared to LAA (β=1.39, P=0.05, OR=3.99,95 %CI 1.01-15.74).

CONCLUSIONS

Long-term outcomes post-first IS vary among TOAST subtypes. Anticoagulant therapy offers long-term benefits among patients of the CE. However, prolonged administration of antiplatelet drugs among SAO patients may be limited in improving function recovery. Physicians should carefully consider treatment options for different IS subtypes to optimize patient outcomes and stroke care effectiveness.

Exploring vertebral artery stump syndrome: An overlooked cause of posterior ischemic strokes. A narrative review of current management options

INTRODUCTION

Stump syndrome is defined as a clinical syndrome resulting from a distal intracranial vessel embolic stroke due to an extracranial vessel occlusion. Similar to the anterior circulation, the recurrence of ischemic strokes in territories supplied by the posterior circulation in the presence of vertebral artery occlusion is termed Vertebral Artery Stump Syndrome (VASS).

MATERIAL AND METHODS

We conducted a literature review, identifying 72 patients with transient ischemic attacks (TIAs) or ischemic strokes attributed to VASS, according to Kawano criteria. We categorized all patients in two groups focusing on the therapeutic management those who underwent primary medical treatment and those who received endovascular or surgical treatment either in acute or chronic phase.

RESULTS

In the anticoagulant therapy group, only 1 patient had a stroke recurrence. Among the 4 on antiplatelets, all had recurrences, but 3 benefited from switching to anticoagulants or endovascular therapy. In the endovascular therapy group, worse outcomes were linked to acute large vessel occlusion. Endovascular treatment of the vertebral artery, in a chronic phase, was explored in literature for recurrent TIAs or minor strokes suggesting that this could be a viable therapeutic alternative when medical treatment failed in preventing recurrence of ischemic stroke.

CONCLUSIONS

Some studies suggest that anticoagulant medical therapy may be beneficial for VASS and endovascular therapy has also been reported for selected patients. However, data on treatment outcomes and prognosis are still underreported, making treatment decisions challenging. Randomized Controlled Trials are needed to establish the optimal treatment approach.

Albumin levels and cerebral collateral circulation in patients with acute ischemic stroke due to intracranial arteriosclerotic: A propensity score-matched analysis

Cerebral collateral circulation (CC) is associated with the recurrence and severity of acute ischemic stroke (AIS), and early identification of poor CC is helpful for the prevention of AIS. In this study we evaluated the association between serum albumin levels and CC in AIS using logistic regression. Propensity score (PS) matching was used to eliminate the effect of confounders, and restricted cubic splines (RCS) were employed to explore potential nonlinear associations between albumin and CC. In unadjusted logistic regression analysis, lower albumin (OR = 0.85, 95% CI = 0.79-0.92) was associated with poor CC, and after adjusting for covariates, the odds of lower albumin for poor CC compared to good CC were 0.86 (95% CI = 0.79-0.94). In the PS cohort, the association of albumin with CC was consistent with those of the original cohort. RCS results showed a linear relationship between albumin and CC (P values of .006 and .08 for overall and nonlinear associations, respectively). The results of this study suggest that lower serum albumin is independently associated with an increased risk of poor CC, which may serve as an effective predictive indicator for poor CC in patients with severe intracranial atherosclerotic stenosis.

Experimental comparison of first-pass effect between direct thromboaspiration and combined thrombectomy in the setting of distal basilar occlusion

BACKGROUND

Studies investigating endovascular therapy in vertebro-basilar stroke have led to controversial results in the past, but recent randomized trials seem to show an effectiveness superiority of endovascular therapy versus best medical treatment. However, uncertainty remains concerning many aspects of thrombectomy in acute basilar artery occlusion, notably technical considerations. This study compared the first-pass effect of direct thromboaspiration and combined thrombectomy in the setting of distal basilar occlusion.

METHODS

An in-vitro experimental set-up was used, consisting of a vascular phantom model and thrombus analogs of different consistencies to mimic human clots. Thrombus analogs were injected into the model through the vertebral artery and flowed to the basilar distal third to mimic a distal basilar occlusion. Ten procedures were performed for each thrombus analog stiffness and technique (direct thromboaspiration versus combined thrombectomy).

RESULTS

Direct thromboaspiration showed an overall first-pass effect rate of 83.3% (25/30) and was particularly effective for ultra-soft and soft clot analogs, but decreased for hard clot analogs. Combined thrombectomy had an overall first-pass effect rate of 56.7% (17/30). The effect rate for ultra-soft and soft clot analogs was 60% and 50% for hard clot analogs. In the softer clot analogs, the stent-retriever device used for the combined thrombectomies tended to deviate the clot analog from a co-axial trajectory with the aspiration catheter.

CONCLUSIONS

In the context of distal basilar occlusion, our in-vitro results showed that higher first-pass effect rates were achieved with direct thromboaspiration compared to combined thrombectomy in all types of thrombus analogs.

First pass effect in patients undergoing endovascular treatment for posterior circulation acute ischemic stroke

OBJECTIVE

This study aims to investigate the impact of first pass effect (FPE) on outcomes in the posterior circulation acute ischemic stroke (PC-AIS) and the independent predictors of FPE.

METHODS

This was a multicenter, retrospective study. PC-AIS patients who underwent endovascular treatment were reviewed. The cohort achieving complete or nearly complete reperfusion (defined as expanded treatment in cerebralischemia [eTICI] ≥ 2c) was categorized into the FPE and multiple pass effect (MPE) groups. FPE was defined as achieving eTICI ≥ 2c with a single pass and without the use of rescue therapy. Modified FPE (mFPE) was defined as meeting the criteria for FPE but with eTICI ≥ 2b. The association of FPE with 90-day clinical outcomes and predictors for FPE were both investigated.

RESULTS

The study included a total of 328 patients, with 69 patients (21 %) in the FPE group. For primary outcome, FPE had a significant higher favorable outcome (mRS ≤ 3) rate than MPE (65.2 % vs. 44.8 %, p = 0.003). Similar outcomes were observed in the mFPE. Furthermore, FPE was significantly associated with favorable outcome (adjusted OR 2.23, 95 % CI 1.06-4.73, p = 0.036). Positive predictors for FPE included occlusion in the distal basilar artery, the first-line aspiration or combination, and cardioembolic etiology. Negative predictors for FPE included hypertension and general anesthesia.

CONCLUSION

For PC-AIS patients due to large or medium vessel occlusion, FPE is associated with favorable clinical outcomes. The first-line techniques of aspiration or combination, as well as avoiding general anesthesia, contribute to a better realization of FPE.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Clinical evaluation of mechanical thrombectomy for patients with posterior circulation occlusion: A retrospective study

OBJECTIVE

Although consensus has been reached regarding the use of mechanical thrombectomy for acute large anterior circulation occlusion, its effectiveness in patients with posterior circulation occlusion remains unclear. This study aimed to establish the determining factors for good clinical outcomes of mechanical thrombectomy for posterior circulation occlusion.

METHODS

We extracted cases of acute large vessel occlusion (LVO) in the posterior circulation from a database comprising 536 patients who underwent mechanical thrombectomy at our hospital between April 2015 and March 2021.

RESULTS

Fifty-two patients who underwent mechanical thrombectomy for LVO in the posterior circulation were identified. Five patients with simultaneous occlusion of the anterior and posterior circulation were excluded; finally, 47 patients were included in this study. The median patient age was 78 years, and 36% of the patients were women. The median National Institutes of Health Stroke Scale (NIHSS) score on admission was 31, the median posterior circulation-Alberta Stroke Program Early Computed Tomography Score (pc-ASPECTS) was 8, and the median Basilar Artery on Computed Tomography Angiography (BATMAN) score was 6. The rate of good recanalization (Thrombolysis in Cerebral Infarction scale grades 2b and 3) was 96%, and a good prognosis (modified Rankin Scale score of 0-2 at 90 days) was achieved in 19 patients (40%). The median pc-ASPECTS was significantly higher in the good prognosis group than in the poor prognosis group (10 vs. 7; p = 0.007). The median NIHSS score at presentation was significantly lower in the good prognosis group than in the poor prognosis group (17 vs. 34; p = 0.02). The median BATMAN score was significantly higher in the good prognosis group than in the poor prognosis group (8 vs. 3.5; p = 0.0002). Multivariate analysis showed that an NIHSS score ≦ 20 at presentation was the only independent factor for good prognoses.

CONCLUSION

The prognosis of mechanical thrombectomy for posterior circulation LVO was better in patients with lower NIHSS scores at presentation.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Endovascular therapy for acute stroke with a large infarct core: A systematic review and meta-analysis

OBJECTIVE

In this meta-analysis, we aimed to investigate the efficacy and safety of endovascular treatment (EVT) for acute ischemic stroke (AIS) patients with large core infarct.

METHODS

Three online databases of Web of Science, PubMed and Scopus were systematically searched. Original studies which evaluated AIS participants with large core infarction who underwent EVT were included. R statistical software was used for statistical analyses. Effect sizes were presented with odds ratios (ORs) with their 95% confidence intervals (CIs). The effect sizes were pooled using random effects modeling.

RESULTS

Including 47 studies and 15,173 patients, this meta-analysis showed that compared with medical management (MM), EVT was significantly associated with decreased odds of mortality (0.67, 95% CI: 0.51-0.87) and increased odds of favorable outcomes, including a modified Rankin Scale of 0-3 (2.36, 95% CI: 1.69-3.291) and of 0-2 (3.54, 95% CI: 1.96-6.4) in 90 days and remarkable improvement in National Institutes of Health Stroke Scale within 48 h after the procedure (3.6, 95% CI:1.32-9.79). Besides, there was a higher chance of intracranial hemorrhage (ICH) development (1.88, 95% CI: 1.32-2.68) but not symptomatic ICH (1.34, 95% CI: 0.78-2.31) in those who underwent EVT.

CONCLUSION

Our study suggests that EVT might be an effective and relatively safe treatment option for the treatment of AIS patients with large vessel occlusion who have large core infarcts, although more large-scale trials are needed to consolidate the results and to make inclusion criteria and the patient selection process clearer.

Impaired consciousness and unilateral limb movement due to acute limb ischemia complicated by acute cerebral infarction: A case report

RATIONALE

The symptoms of impaired consciousness and unilateral motor impairments are a perfect scenario for cerebral infarction, and a physician can easily miss the findings of limb ischemia on the patient paralyzed side even if acute limb ischemia (ALI) occurs on that side. The purpose of this case report is to reiterate the need to suspect ALI in patients with impaired consciousness who cannot complain of symptoms such as abnormal limb paresthesia or pain.

PATIENT CONCERNS

An 89-year-old woman with impaired consciousness and motor impairment of the left upper and lower extremities was transported to our hospital.

DIAGNOSES

Brain magnetic resonance imaging showed a suspected cerebral infarction in the posterior circulation; contrast-enhanced computed tomography showed occlusion of the left axillary artery and left femoral artery; and ultrasonography showed occlusion of the right popliteal artery.

INTERVENTIONS

Cerebral angiography was performed simultaneously with surgical thrombectomy to treat the ALI. Mechanical thrombectomy was not performed for cerebral infarction.

OUTCOMES

Although motor impairment of the left upper and lower extremities persisted, the patient successfully underwent limb salvage.

LESSONS

Both cerebral infarction and ALI require early diagnosis and treatment. This rare case of cerebral infarction complicated by ALI emphasizes the need to avoid missing the signs of ALI in patients with impaired consciousness.

Neurofunctional correlates of a neurorehabilitation system based on eye movements in chronic stroke impairment levels: A pilot study

INTRODUCTION

Rehabilitation after a stroke is widely considered fundamental to improve secondary functional impairments. Accessible methods based on motor learning, motor transfer and virtual environments are necessary to help to improve stroke patients' quality of life.

OBJECTIVES

Continuing the line of our previous studies, this work investigated the effect of our new and innovative game-based virtual reality training using the control of virtual objects with gaze in three chronic stroke survivors.

METHODS

All participants performed an eye-controlled virtual training task for 4 weeks. Pre- and post-training evaluation were carried out with the Fugl-Meyer Assessment for upper extremity scale as well as performing a tracking task inside an MRI scanner with a MRI-compatible eye-tracker or a joystick.

RESULTS

Neural results for each participant show the increase of activity in the motor cortex, basal ganglia and cerebellum for both effectors (hand or eye).

CONCLUSION

These promising results have a potential application as a new game-based neurorehabilitation approach to enhance the motor activity of stroke patients.

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

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

Endovascular Treatment for Acute Basilar Artery Occlusion: A Fragility Index Meta-Analysis

INTRODUCTION

High-quality evidence regarding the use of endovascular treatment (EVT) in patients with acute basilar artery occlusion (BAO) has been provided by recently completed randomized controlled clinical trials (RCTs).

METHODS

We conducted a systematic review and meta-analysis including all available RCTs that investigated efficacy and safety of EVT in addition to best medical treatment (BMT) versus BMT alone for BAO. The random-effects model was used, while the fragility index (FI) was calculated for dichotomous outcomes of interest.

RESULTS

Four RCTs were included comprising a total of 988 patients with acute BAO (mean age: 65.6 years, 70% men, median NIHSS: 24, 39% pretreatment with intravenous thrombolysis). EVT was related to higher likelihood of good functional outcome (RR: 1.54; 95% CI: 1.16-2.05; I2 = 60%), functional independence (RR: 1.83; 95% CI: 1.08-3.08; I2 = 79%) and reduced disability at 3 months (adjusted common OR: 1.96; 95% CI: 1.26-3.05; I2 = 59%) compared to BMT alone. Despite that EVT was associated with a higher risk for symptomatic intracranial hemorrhage (RR: 7.78; 95% CI: 2.36-25.61; I2 = 0%) and any intracranial hemorrhage (RR: 2.85; 95% CI: 1.50-5.44; I2 = 16%), mortality at 3 months was lower among patients that received EVT plus BMT versus BMT alone (RR: 0.76; 95% CI: 0.65-0.89; I2 = 0%). However, sufficient robustness was not evident in any of the reported associations (FI < 10) including the overall effect regarding the primary outcome. The former associations were predominantly driven by RCTs with recruitment limited in China.

CONCLUSIONS

EVT combined with BMT is associated with a higher likelihood of achieving good functional outcomes and a lower risk of death at 3 months compared to BMT alone, despite the higher risk of sICH. An individual-patient data meta-analysis is warranted to uncover and adjust for potential sources of heterogeneity and to provide further insight.

First pass effect in posterior circulation occlusions: Analysis from the CICAT registry

BACKGROUND

The first pass effect (FPE) is an independent predictor of functional independence in patients with large vessel occlusion in anterior circulation ischemic strokes. However, whether it predicts outcome in posterior circulation large vessel occlusion (PC-LVO) is uncertain. We aimed to study the frequency, characteristics, and predictors of FPE and its association with clinical outcomes in PC-LVO.

METHOD

We performed an analysis from the prospective CICAT Registry. All patients with PC-LVO who underwent endovascular therapy between January 2016 and January 2020 were included. A centrally assessed clinical follow-up was performed at 3 months by blinded investigators. FPE was defined as the achievement of modified Thrombolysis In Cerebral Infarction 3 in a single pass of the endovascular thrombectomy device, and multi-pass effect (MPE) if it was achieved in more than one pass. A multivariable analysis was performed to identify whether FPE is an independent predictor of functional independence defined as a modified Rankin Score of 0-2.

RESULTS

We analyzed data from 265 patients in who FPE was achieved in 105 (39.6%). Patients with FPE were more likely to achieve functional independence compared to the non-FPE group (52.4% vs 25.1%, p < .001) and the MPE group (52.4% vs 26.7%, p < .001). FPE was independently associated with functional independence (adjusted odds ratio (aOR): 2.10, 95% confidence interval (CI) 1.01-4.37) but MPE was not (aOR: 0.92, 95% CI 0.40-2.13). Independent predictors of FPE were the use of direct aspiration, embolic mechanism of stroke, and the absence of general anesthesia (GA) use.

CONCLUSIONS

FPE is an independent predictor of functional independence in PC-LVO and was associated with a significantly better outcome than MPE.

Prevalence and Associated Factors of Cognitive Impairment Among Stroke Survivors at Comprehensive Specialized Hospitals in Northwest Ethiopia: Multi-Centered Cross-Sectional Study

Background

Deficit in cognitive impairment is the most serious of the stroke sequelae. Post-stroke cognitive impairment is associated with impaired daily living activities and decreased capacity for independent living and functional performance. As a result, the purpose of this study was to determine the prevalence and associated factors of cognitive impairment among stroke survivors at comprehensive specialized hospitals in Ethiopia's Amhara region by 2022.

Methods

A multi-centered cross-sectional study was designed at an institution. During the study period. Data was gathered by conducting structured questionnaire interviews with participants and reviewing medical charts with trained data collectors. The participants were chosen using a systematic random sampling technique. The Montreal cognitive assessment basic was used to assess cognitive impairment. Descriptive statistics, binary and multivariate logistic regression methods were used to analyze the data. The Hosmer-Lemeshow goodness-of-fit test was used to assess the fitness of the model. The AOR with a P value of 0.05 at 95% CI was reported, and variables were considered statistically significant.

Results

This study enrolled 422 stroke survivors. Overall, 58.3% of stroke survivors had cognitive impairment (95% CI 53.4-63.0%). The study participants' age with AOR; 7.12 (4.40-11.45), being hypertensive with AOR; 7.52 (3.46-16.35), arriving at the hospital after 24 hours with AOR; 4.33 (1.49-12.05), less than three months after stroke with AOR; 4.83 (3.95-12.19), dominant hemisphere lesion with AOR; 4.83 (3.95-12.19) and being illiterate with AOR; 5.26 (4.43-18.64) were found significant factors.

Conclusion

Cognitive impairment was discovered to be relatively common among stroke survivors in this study. More than half of stroke survivors who attended comprehensive specialized hospitals during the study period were found to have cognitive impairment. Age, hypertension, arriving at the hospital after 24 hours, less than three months after stroke, dominant hemisphere lesion, and illiterate educational status were all significant factors in cognitive impairment.

Influence of tirofiban on stroke outcome after mechanical thrombectomy in acute vertebrobasilar artery occlusion

BACKGROUND

Even undergoing mechanical thrombectomy (MT), patients with acute vertebrobasilar artery occlusion (AVBAO) still have a high rate of mortality. Tirofiban is a novel antiplatelet agent which is now widely empirically used in acute ischemic stroke (AIS). In this study, we aimed to evaluate the safety and efficacy of tirofiban as adjunctive therapy for MT in AVBAO.

METHODS

From October 2016 to July 2021, consecutive AVBAO patients receiving MT were included in the prospective stroke registry. The short-term outcomes were (1) symptomatic intracerebral hemorrhage (sICH); (2) in-hospital death; (3) National Institute of Health Stroke Scale (NIHSS) at discharge. The Long-term outcomes were: (1) modified Rankin Scale (mRS) at 3 months; (2) death at 3 months.

RESULTS

A total of 130 eligible patients were included in the study, 64 (49.2%) patients received tirofiban. In multivariate regression analysis, no significant differences were observed in all outcomes between the tirofiban and non-tirofiban group [sICH (adjusted OR 0.96; 95% CI, 0.12-7.82, p = 0.97), in-hospital death (adjusted OR 0.57; 95% CI, 0.17-1.89, p = 0.36), NIHSS at discharge (95% CI, -2.14-8.63, p = 0.24), mRS (adjusted OR 1.20; 95% CI, 0.40-3.62, p = 0.75), and death at 3 months (adjusted OR 0.83; 95% CI, 0.24-2.90, p = 0.77)].

CONCLUSIONS

In AVBAO, tirofiban adjunctive to MT was not associated with an increased risk of sICH. Short-term (in-hospital death, NIHSS at discharge) and long-term outcomes (mRS and death at 3 months) seem not to be influenced by tirofiban use.

Endovascular Thrombectomy for Acute Basilar Artery Occlusion: Latest Findings and Critical Thinking on Future Study Design

Randomized controlled trials (RCTs) have demonstrated powerful efficacy of endovascular thrombectomy (EVT) for large vessel occlusion in the anterior circulation. The effect of EVT for acute basilar artery occlusion (BAO) in the posterior circulation remains unproven. Here, we highlight the latest findings of observational studies and RCTs of EVT for BAO, with a focus on the predictors of functional outcomes, the limitations of recent RCTs, and critical thinking on future study design. Pooled data from large retrospective studies showed 36.4% favorable outcome at 3 months and 4.6% symptomatic intracranial hemorrhage (sICH). Multivariate logistic regression analysis revealed that higher baseline NIHSS score, pc-ASPECTS < 8, extensive baseline infarction, large pontine infarct, and sICH were independent predictors of poor outcome. Two recent randomized trial BEST (Endovascular treatment vs. standard medical treatment for vertebrobasilar artery occlusion) and BASICS (Basilar Artery International Cooperation Study) failed to demonstrate significant benefit of EVT within 6 or 8 h after stroke symptom onset. The limitations of these studies include slow enrollment, selection bias, high crossover rate, and inclusion of patients with mild deficit. To improve enrollment and minimize risk of diluting the overall treatment effect, futile recanalization and re-occlusion, optimal inclusion/exclusion criteria, including enrollment within 24 h of last known well, NIHSS score ≥ 10, pc-ASPECTS ≥ 8, no large pontine infarct, and the use of rescue therapy for underlying atherosclerotic stenosis, should be considered for future clinical trials.

First-pass effect in patients with acute vertebrobasilar artery occlusion undergoing thrombectomy: insights from the PERSIST registry

BACKGROUND

Achieving rapid and complete vascular recanalization in patients with acute large vessel occlusion can significantly improve patients' prognosis.

OBJECTIVE

We aimed to investigate the potential contribution of the first-pass effect (FPE) to the clinical outcome of patients with acute vertebrobasilar artery occlusion (VBAO).

METHODS

We retrospectively analyzed the data of patients who underwent endovascular thrombectomy (EVT) caused by VBAO in a multicentered retrospective registry dataset. FPE was defined as successful recanalization [modified thrombolysis in cerebral infarction (mTICI) 2b/3 as modified FPE (mFPE); mTICI 3 as true FPE (tFPE)] after one pass of the device without rescue therapy. The baseline characteristics and procedural and clinical outcomes were analyzed. Multivariate analysis was used to explore the predictors of FPE and the relationship between FPE and 90-day prognosis.

RESULTS

A total of 508 patients (age, 63.7 ± 13.1 years, male, 71.6%) were finally included, 29.9% (152/508) of whom achieved mFPE, and 21.1% (107/508) of whom achieved tFPE. FPE was significantly associated with improved clinical outcomes, regardless of mFPE [odds ratio (OR): 0.601, 95% confidence interval (CI): 0.370-0.977, p = 0.040] and tFPE (OR: 0.547, 95% CI: 0.318-0.940, p = 0.029). The use of contact aspiration, favorable collateral status, cardioembolic etiology, and basilar artery occlusion were statistically significant predictors of mFPE and tFPE, whereas hypertension was a negative predictor. Intravenous (IV) recombinant tissue plasminogen activator (rt-PA) prior to EVT was a positive predictor of mFPE but not of tFPE.

CONCLUSION

FPE was associated with significantly favorable outcomes in EVT patients with VBAO. The predictors of FPE include infarct etiology, the site of occlusion, collateral status, EVT strategies, and IV rt-PA bridging strategies.

TRIAL REGISTRATION NUMBER

URL: http://www.chictr.org.cn/; Unique identifier: ChiCTR2000033211.

What You Always Wanted to Know about Endovascular Therapy in Acute Ischemic Stroke but Never Dared to Ask: A Comprehensive Review

In 2015, mechanical thrombectomy (MT) in combination with intravenous thrombolysis was demonstrated to be superior to best medical treatment alone in patients with anterior circulation stroke. This finding resulted in an unprecedented boost in endovascular stroke therapy, and MT became widely available. MT was initially approved for patients presenting with large vessel occlusion in the anterior circulation (intracranial internal carotid artery or proximal middle cerebral artery) within a 6-hour time window. Eventually, it was shown to be beneficial in a broader group of patients, including those without known symptom-onset, wake-up stroke, or patients with posterior circulation stroke. Technical developments and the implementation of novel thrombectomy devices further facilitated endovascular recanalization for acute ischemic stroke. However, some aspects remain controversial. Is MT suitable for medium or very distal vessel occlusions? Should emergency stenting be performed for symptomatic stenosis or recurrent occlusion? How should patients with large vessel occlusion without disabling symptoms be treated? Do certain patients benefit from MT without intravenous thrombolysis? In the era of personalized decision-making, some of these questions require an individualized approach based on comorbidities, imaging criteria, and the severity or duration of symptoms. Despite its successful development in the past decade, endovascular stroke therapy will remain a challenging and fascinating field in the years to come. This review aims to provide an overview of patient selection, and the indications for and execution of MT in patients with acute ischemic stroke.

Predictors of first pass effect and effect on outcomes in mechanical thrombectomy for basilar artery occlusion

INTRODUCTION

For patients undergoing endovascular thrombectomy (EVT), those who are recanalized with a successful single pass (first pass effect, FPE) have better functional outcomes than those who do not. There is a scarcity of data regarding predictors of FPE in basilar artery occlusion (BAO). We aim to determine what characteristics may predict FPE for posterior circulation thrombectomies in a cohort of patients undergoing EVT for BAO.

METHODS

We reviewed prospectively-collected data for patients presenting to a comprehensive stroke center with BAO between December 2015 and April 2019. Patients were included in this study if they underwent manual aspiration thrombectomy for BAO. Patients were excluded if they had occlusions of the posterior cerebral or vertebral arteries or if they had tandem lesions. Patients were stratified by whether FPE or modified FPE (mFPE) was achieved, and multivariate logistic regression analyses were performed to identify predictors of FPE and the effect of FPE on clinical outcome.

RESULTS

100 patients with BAO underwent thrombectomy. Mean age was 64.7 ± 16.7, 42% were female, and median NIHSS was 20 (IQR 11-27). 33% met criteria for FPE and 60% for mFPE. Univariate analysis identified female gender, lack of IV-tPA use, pcASPECTS, atrial fibrillation, and hyperlipidemia as possible predictors of FPE. On multivariate analysis, age, pcASPECTs, atrial fibrillation, hyperlipidemia and IV-tPA use were not independent predictors of FPE or mFPE. Female gender was an independent predictor of mFPE (p = 0.02), but not FPE (p = 0.18). FPE was a predictor of mRS 0-2 at 90 days (p = 0.04). Predictors of mortality were age (p < 0.01), baseline NIHSS (p < 0.01) and mFPE (p = 0.01).

CONCLUSION

In this cohort analysis of 100 patients with basilar artery occlusion undergoing manual aspiration thrombectomy, female gender was associated with mFPE but not FPE. Previously-reported anterior circulation FPE predictors including age, ASPECTS and atrial fibrillation were not predictors of FPE in this cohort of patients with BAO.

A Predictive Model for the Risk of Posterior Circulation Stroke in Patients with Intracranial Atherosclerosis Based on High Resolution MRI

Intracranial vertebrobasilar atherosclerosis is the main cause of posterior circulation ischemic stroke. We aimed to construct a predictive model for the risk of posterior circulation ischemic stroke in patients with posterior circulation atherosclerosis based on high-resolution MRI (HR-MRI). A total of 208 consecutive patients with posterior circulation atherosclerosis confirmed by HR-MRI, from January 2020 to July 2021, were retrospectively assessed. They were assigned to the posterior circulation stroke (49 patients) and non-posterior circulation stroke group (159 patients) based on clinical presentation and diffusion-weighted imaging (DWI). Demographic data, risk factors of atherosclerosis, laboratory findings, and imaging characteristics were extracted from electronic health records. Plaque features were investigated by HR-MRI. Fifty-three clinical or imaging features were used to derive the model. Multivariable logistic regression analysis was employed to construct the prediction model. The nomogram was evaluated for calibration, differentiation, and clinical usefulness. Plaque enhancement, plaque irregular surface morphology, artery location of plaque, and dorsal quadrant of plaque location were significant predictors for posterior circulation stroke in patients with intracranial atherosclerosis. Subsequently, these variables were selected to establish a nomogram. The model showed good distinction (C-index 0.830, 95% CI 0.766-0.895). The calibration curve also showed excellent consistency between the prediction of the nomogram and the observed curve. Decision curve analysis further demonstrated that the nomogram conferred significantly high clinical net benefit. The nomogram calculated from plaque characteristics in HR-MRI may accurately predict the posterior circulation stroke occurrence and be of great help for stratification of stroke decision making.

Mechanical thrombectomy for acute posterior cerebral artery stroke; Feasibility and predictors of outcome

PURPOSE

The territorial involvement and the clinical benefit of endovascular therapy (EVT) of the posterior cerebral artery (PCA) occlusion may vary between patients. The purpose of this study was to investigate the feasibility of mechanical thrombectomy (MT) in isolated posterior cerebral artery occlusions (IPCAOs) and the prognostic factors of EVT.

METHODS

Forty-eight patients with acute PCA occlusion who underwent EVT between Mar 2008 and Apr 2021 from 2 tertiary centers were retrospectively analyzed. Clinical characteristics, imaging and perfusion abnormalities, and angiographic and clinical outcomes were analyzed. Ischemic changes were assessed with the posterior circulation Acute Stroke Prognosis Early Computed Tomography Score (pc-ASPECTS). Perfusion abnormalities were assessed using automated software for Tmax volume measurement and identification of Tmax involved in PCA eloquent areas.

RESULTS

The IPCAO sites were P1 (n = 17) and P2 (n = 31). Overall successful recanalization (mTICI 2b/3) was achieved in 68.8% (33/48) and excellent outcome (90-day mRS 0-1) in 52.1% (25/48) of the patients. Excellent/non-excellent outcome was associated with male sex (p = 0.036), admission NIHSS (p = 0.002), pc-ASPECTS (p = 0.035), Tmax > 6 s involvement of the midbrain-thalamus (p = 0.008), first-line stent-retriever thrombectomy (p = 0.036), complete recanalization (p = 0.009), and modified first pass effect (FPE, p = 0.047). Tmax>6 s involvement of the midbrain-thalamus was an independent predictor for non-excellent outcome on multivariable analysis.

CONCLUSION

Acute stroke from IPCAO may be successfully treated with EVT. Tmax > 6 s involvement of the midbrain-thalamus on perfusion imaging may be a predictor for clinical outcome.

Posterior Circulation Endovascular Thrombectomy for Large Vessels Occlusion in Patients Presenting with NIHSS Score ≤ 10

Mechanical thrombectomy (MT) is currently the gold standard treatment for ischemic stroke due to large vessel occlusion (LVO). However, the evidence of clinical usefulness of MT in posterior circulation LVO (pc-LVO) is still doubtful compared to the anterior circulation, especially in patients with mild neurological symptoms. The database of 10 high-volume stroke centers in Europe, including a period of three year and a half, was screened for patients with an acute basilar artery occlusion or a single dominant vertebral artery occlusion ("functional" BAO) presenting with a NIHSS ≤10, and with at least 3 months follow-up. A total of 63 patients were included. Multivariate analysis demonstrated that female gender (adjusted OR 0.04; 95% CI 0-0.84; p = 0.04) and combined technique (adj OR 0.001; 95% CI 0-0.81; p = 0.04) were predictors of worse outcome. Higher pc-ASPECTS (adj OR 4.75; 95% CI 1.33-16.94; p = 0.02) and higher Delta NIHSS (adj OR 2.06; 95% CI 1.16-3.65; p = 0.01) were predictors of better outcome. Delta NIHSS was the main predictor of good outcome at 90 days in patients with posterior circulation LVO presenting with NIHSS score ≤ 10.

[Time is Brain - Preclinical Emergency Care for Acute Ischemic Stroke]

Stroke is one of the most common neurological emergencies and requires rapid detection and treatment (time is brain). There is still insufficient knowledge about stroke warning signs. It is therefore of crucial importance that trained personnel in the preclinical setting recognize the relevant warning symptoms and collect the necessary information to quickly refer the patient to the appropriate additional care structure. For this purpose, training of the emergency medical services (EMS) and the correct triage are of particular importance. The on-site assessment of a patient with a suspected stroke by EMS should include airway, breathing, vital functions, a basic neurological examination, blood glucose testing and cardiac monitoring.Patients with suspected acute ischemic stroke should be brought to the nearest hospital with a stroke unit, ideally connected with a tertiary stroke centre. From there, once the primary diagnosis has been carried out and appropriate therapy initiated, the patient can be transferred to a thrombectomy center if necessary. To improve supply times, teleradiological networking plays a major role both between clinics of different levels of care and in communication between pre- and intra-hospital care providers. Also, the use of mobile stroke units can improve preclinical stroke care and reduce delays in access to intravenous thrombolytic therapy and mechanical thrombectomy. The identification of preclinical biomarkers could also save time.

Endovascular therapy in basilar artery occlusion in Sweden 2016-2019-a nationwide, prospective registry study

Purpose

We present the first nationwide study on endovascular therapy for basilar artery occlusion (BAO) from early hospital management to 3-month outcome.

Methods

Data were collected on all acute ischaemic stroke patients registered 2016–2019 in the two national quality registers for stroke care and endovascular therapy (EVT), receiving EVT for BAO and subclassified into proximal, middle and distal.

Results

In all, 251 patients were included: 69 proximal, 73 middle and 109 distal BAO. Patients with proximal BAO were younger (66, middle 71, distal 76, p < 0.0001), less often female (27.5%, middle 47.9%, distal 47.7%, p = 0.015), more often smokers (28.6%, middle 20.3%, distal 11.5%, p < 0.0001), and fewer had atrial fibrillation (13.2%, middle 24.7%, distal 48.6%, p < 0.0001). Level of consciousness and NIHSS score did not differ by BAO subtype and 52.2% were alert on admission. Time from groin puncture to revascularization was significantly longer in patients with proximal BAO (71, middle 46, distal 42 min, p < 0.0001), and angioplasty and/or stenting was more often performed in patients with proximal (43.4%) and middle (27.4%) than distal (6.4%) BAO (p < 0.0001). Cumulative 90-day mortality was 38.6% (proximal 50.7%, middle 32.9%, distal 34.9%, p = 0.02). Older and pre-stroke dependent patients had higher mortality, as did patients in whom angioplasty/stenting was performed.

Conclusion

We confirm a serious outcome in BAO despite endovascular therapies, and demonstrate important differences relating to occlusion location in baseline characteristics, procedural time, therapeutic measures and outcome. Further in-depth analyses of factors affecting outcome in BAO are warranted.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00234-021-02843-3.

Value of machine learning to predict functional outcome of endovascular treatment for acute ischaemic stroke of the posterior circulation

PURPOSE

Clinical outcomes vary considerably among individuals with vessel occlusion of the posterior circulation. In the present study we evaluated machine learning algorithms in their ability to discriminate between favourable and unfavourable outcomes in patients with endovascular treatment of acute ischaemic stroke of the posterior circulation.

METHODS

This retrospective study evaluated three algorithms (generalised linear model, K-nearest neighbour and random forest) to predict functional outcomes at dismissal of 30 patients with acute occlusion of the basilar artery who were treated with thrombectomy. Input variables encompassed baseline as well as peri and postprocedural data. Favourable outcome was defined as a modified Rankin scale score of 0-2 and unfavourable outcome was defined as a modified Rankin scale score of 3-6. The performance of the algorithms was assessed with the area under the receiver operating curve and with confusion matrixes.

RESULTS

Successful reperfusion was achieved in 83%, with 30% of the patients having a favourable outcome. The area under the curve was 0.93 for the random forest model, 0.86 for the K-nearest neighbour model and 0.78 for the generalised linear model. The accuracy was 0.69 for the generalised linear model and 0.84 for the random forest and the K nearest neighbour models.

CONCLUSION

Favourable and unfavourable outcomes at dismissal of patients with acute ischaemic stroke of the posterior circulation can be predicted immediately after the follow-up non-enhanced computed tomography using machine learning.

Revascularization Outcome Prediction for A Direct Aspiration-First Pass Technique (ADAPT) from Pre-Treatment Imaging and Machine Learning

A direct aspiration-first pass technique (ADAPT) has recently gained popularity for the treatment of large vessel ischemic stroke. Here, we sought to create a machine learning-based model that uses pre-treatment imaging metrics to predict successful outcomes for ADAPT in middle cerebral artery (MCA) stroke cases. In 119 MCA strokes treated by ADAPT, we calculated four imaging parameters-clot length, perviousness, distance from the internal carotid artery (ICA) and angle of interaction (AOI) between clot/catheter. We determined treatment success by first pass effect (FPE), and performed univariate analyses. We further built and validated multivariate machine learning models in a random train-test split (75%:25%) of our data. To test model stability, we repeated the machine learning procedure over 100 randomizations, and reported the average performances. Our results show that perviousness (p = 0.002) and AOI (p = 0.031) were significantly higher and clot length (p = 0.007) was significantly lower in ADAPT cases with FPE. A logistic regression model achieved the highest accuracy (74.2%) in the testing cohort, with an AUC = 0.769. The models had similar performance over the 100 train-test randomizations (average testing AUC = 0.768 ± 0.026). This study provides feasibility of multivariate imaging-based predictors for stroke treatment outcome. Such models may help operators select the most adequate thrombectomy approach.

Efficacy of Mechanical Thrombectomy using Penumbra ACETM Aspiration Catheter Compared to Stent Retriever SolitaireTM FR in Patients with Acute Ischemic Stroke

Background: Mechanical thrombectomy is the standard therapy in patients with acute ischemic stroke (AIS). The primary aim of our study was to compare the procedural efficacy of the direct aspiration technique, using Penumbra ACE^TM aspiration catheter, and the stent retriever technique, with a Solitaire^TM FR stent. Secondarily, we investigated treatment-dependent and treatment-independent factors that predict a good clinical outcome. Methods: We analyzed our series of mechanical thrombectomies using a Solitaire^TM FR stent and a Penumbra ACE^TM catheter. The clinical and radiographic data of 76 patients were retrospectively reviewed. Using binary logistic regression, we looked for the predictors of a good clinical outcome. Results: In the Penumbra ACE^TM group we achieved significantly higher rates of complete vessel recanalization with lower device passage counts, shorter recanalization times, shorter procedure times and shorter fluoroscopy times (p < 0.001) compared to the Solitaire^TM FR group. We observed no significant difference in good clinical outcomes (52.4% vs. 56.4%, p = 0.756). Predictors of a good clinical outcome were lower initial NIHSS scores, pial arterial collateralization on admission head CT angiography scan, shorter recanalization times and device passage counts. Conclusions: The aspiration technique using Penumbra ACE^TM catheter is comparable to the stent retriever technique with Solitaire^TM FR regarding clinical outcomes.