Nomogram for predicting early neurological deterioration in patients with mild large and medium vessel occlusion stroke intended for medical management: a multicenter retrospective study

BACKGROUND

Accurately forecasting early neurological deterioration of ischemic origin (ENDi) following medical management may aid in identifying candidates for thrombectomy. We aimed to develop and validate a nomogram to predict ENDi in patients with mild large and medium vessel occlusion stroke intended for medical management.

METHODS

Two hundred and forty-eight patients were enrolled (173 and 75 randomised into training and validation cohorts). The risk factors were identified using logistic regression analyses. A nomogram was constructed based on the risk factors identified. The discrimination, calibration, and clinical practicability of the nomogram were assessed using receiver operating characteristic curve (ROC) analysis, the Hosmer-Lemeshow test, and decision curve analysis (DCA), respectively.

RESULTS

ENDi was detected in 44 (17.7%) patients. Four predictors were identified in the training cohort and entered into the nomogram including age, symptom fluctuation characteristics, presence of core infarct, and occlusion site. ROC analysis showed that the area under the curve was 0.930 (95% CI 0.884 to 0.976) and 0.889 (95% CI 0.808 to 0.970) in the training and validation cohorts, respectively. The Hosmer-Lemeshow test yielded a mean absolute error of 0.025 and 0.038, respectively, for the two cohorts. The DCA showed that the nomogram model had superior practicality and accuracy across the majority of the threshold probabilities.

CONCLUSION

The proposed nomogram showed a favourable predictive performance for ENDi in patients with mild large and medium vessel occlusion stroke intended for medical management. For such patients, immediate thrombectomy or at least intensive medical monitoring may be reasonable to avoid delays in rescue thrombectomy.

Circle of Willis integrity in acute middle cerebral artery occlusion: does the posterior communicating artery matter?

BACKGROUND

Collateral circulation is an important determinant of outcome in people with acute ischemic stroke due to large vessel occlusion (LVO).

OBJECTIVE

To explore the impact of the circle of Willis (CW) anatomical characteristics ipsilateral to the occlusion site, particularly the posterior communicating artery (PComA) and the A1-portion of the anterior cerebral artery (A1-ACA), on stroke outcomes in a cohort of patients with LVO and middle cerebral artery (MCA) occlusion, undergoing endovascular thrombectomy (EVT).

METHODS

This is a retrospective cohort study performed in a comprehensive tertiary stroke center. The study population consisted of consecutive patients with LVO with proximal MCA occlusion (M1) between June 2016 and April 2021, undergoing EVT. Demographic, clinical, and imaging information was extracted from patient files. Patency and diameters of ipsilateral A1-ACA and PComA were manually measured on admission CT angiography images in the core laboratory.

RESULTS

One hundred and five patients with LVO comprised the study cohort, mean age 72.3 years, 43.8% were male, mean National Institutes of Health Stroke Scale score at admission 15.2. The cohort was grouped according to CW vessel characteristics. On univariate analysis, a well-developed PComA was associated with lower rates of hemorrhagic transformation (1.8% vs 14.3%, P=0.01) and a trend towards lower mortality rates (8.9% vs 20.4%, P=0.08).On multivariable regression analysis a well-developed PComA emerged as an independent predictor for survival (aOR=0.09, 95% CI 0.01 to 0.4 for survival at discharge, P=0.009, aOR=0.22, 95% CI 0.05 to 0.8 for survival at 90 days, P=0.02).

CONCLUSIONS

In a cohort of patients with LVO due to M1 occlusion undergoing EVT, a well-developed PComA was associated with significantly lower hemorrhagic transformation rates, a trend towards better functional outcomes, and independently predicted survival. Larger studies are needed to understand the differential effect of CW collateral conduits on stroke outcome and evaluate the practicality of incorporating such factors in the clinical decision-making process prior to EVT.

Futile recanalization in patients with basilar artery occlusion: assessment of the underlying etiology and the role of perfusion imaging

BACKGROUND

Futile recanalization (FR) after endovascular therapy (EVT) is common in basilar artery occlusion (BAO). The purpose of this study was to investigate the predictors of FR in the posterior circulation with an emphasis on the role of perfusion imaging and its relation to the underlying etiology.

METHODS

We included BAO patients who had pretreatment perfusion imaging and successful recanalization after EVT. Patients were dichotomized into futile and non-futile groups according to the favorable functional outcome at 90 days (modified Rankin Scale (mRS) 0-3). Perfusion abnormalities were assessed using an automated software for Tmax volume measurement and identification of hypoperfusion area based on Tmax>6 s involvement of the pons-midbrain-thalamus (PMT), cerebellum, and temporo-occipital lobe.

RESULTS

Of the 134 enrolled patients, the incidence of FR was 47.8% (64/134). Multivariate logistic analysis showed that a higher National Institutes of Health Stroke Scale (NIHSS) score on admission (adjusted OR (aOR) 1.066; 95% CI 1.011 to 1.125), a longer onset-to-recanalization time (aOR 1.002; 95% CI 1.001 to 1.004), incomplete recanalization (aOR 3.909; 95% CI 1.498 to 10.200), and PMT hypoperfusion (aOR 4.444; 95% CI 1.203 to 16.415) were independent predictors of FR. In patients with embolic occlusion of etiology, PMT hypoperfusion was associated with FR (aOR 8.379; 95% CI 1.377 to 50.994), whereas intracranial atherosclerotic stenosis (ICAS)-related occlusion was not (p=0.587).

CONCLUSIONS

In patients with BAO, the likelihood of FR is associated with PMT hypoperfusion on pretreatment perfusion imaging. In particular, PMT hypoperfusion may be used as an imaging predictor of FR in patients with embolic cause of BAO.

Computed tomography perfusion deficit volume predicts the functional outcome of endovascular therapy for basilar artery occlusion

OBJECTIVES

To investigate the relationship between baseline computed tomography perfusion deficit volumes and functional outcomes in patients with basilar artery occlusion (BAO) undergoing endovascular therapy.

METHODS

This was a single-center study in which the data of 64 patients with BAO who underwent endovascular therapy were retrospectively analyzed. All the patients underwent multi-model computed tomography on admission. The posterior-circulation Acute Stroke Prognosis Early Computed Tomography Score was applied to assess the ischemic changes. Perfusion deficit volumes were obtained using Syngo.via software. The primary outcome of the analysis was a good functional outcome (90-day modified Rankin Scale score ≤ 3). Logistic regression and receiver operating characteristic curves were used to explore predictors of functional outcome.

RESULTS

A total of 64 patients (median age, 68 years; 72 % male) were recruited, of whom 26 (41 %) patients achieved good functional outcomes, while 38 (59 %) had poor functional outcomes. Tmax > 10 s, Tmax > 6 s, and rCBF < 30 % volume were independent predictors of good functional outcomes (odds ratio range, 1.0-1.2; 95 % confidence interval [CI], 1.0-1.4]) and performed well in the receiver operating characteristic curve analyses, exhibiting positive prognostic value; the areas under the curve values were 0.85 (95 % CI, 0.75-0.94), 0.81 (95 % CI, 0.70-0.90), and 0.78 (95 % CI, 0.67-0.89).

CONCLUSION

Computed tomography perfusion deficit volume represents a valuable tool in predicting high risk of disability and mortality in patients with BAO after endovascular treatment.

Asymmetric deep cerebral venous filling predicts poor outcome of acute basilar artery occlusion after endovascular treatment

OBJECTIVE

To explore the relationship between asymmetric deep cerebral venous (ADCV) filling and poor outcomes after endovascular treatment (EVT) in patients with acute basilar artery occlusion (ABAO).

METHODS

ABAO patients were selected from a prospectively collected data at our center. The DCV filling was evaluated using computed tomography perfusion (CTP)-derived reconstructed 4D-DSA or mean venous map. ADCV filling was defined as the internal cerebral vein (ICV), thalamostriate vein (TSV), or basal vein of Rosenthal (BVR) presence of ipsilateral filling defects or delayed opacification compared to the contralateral side. Poor prognosis was defined as a modified Rankin scale score >3 at the 90-day follow-up.

RESULTS

A total of 90 patients were enrolled in the study, with a median Glasgow Coma Scale of 6, 46 (51.1%) showed ADCV filling, 59 (65.6%) had a poor prognosis, and 27 (30.7%) had malignant cerebellar edema (MCE). Multivariate adjusted analysis revealed significant associations between asymmetric TSV and poor prognosis (odds ratio, 9.091, p = 0.006); asymmetric BVR (OR, 9.232, p = 0.001) and asymmetric ICV (OR, 4.028, p = 0.041) were significantly associated with MCE.

CONCLUSION

Preoperative ADCV filling is an independent influencing factor for the poor outcome after EVT in ABAO patients.

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

Introduction and purpose

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

Methods

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

Results

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

Conclusion

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

Adjunct Intraarterial or Intravenous Tirofiban Versus No Tirofiban After Successful Recanalization of Basilar Artery Occlusion Stroke: The BASILAR Registry

BACKGROUND

Approximately half of patients who achieve successful reperfusion do not achieve functional independence. The present study sought to investigate the clinical outcomes and safety of intraarterial or intravenous tirofiban as adjunct therapy in patients with acute basilar artery occlusion who had achieved successful recanalization with endovascular treatment.

METHODS AND RESULTS

In the national, prospective BASILAR (Endovascular Treatment for Acute Basilar Artery Occlusion Study) registry, 458 patients who met inclusion criteria were divided into 3 groups based on tirofiban administration (no tirofiban, n=262; intravenous tirofiban, n=101; intraarterial+intravenous tirofiban, n=95). Their clinical outcomes were compared with 90-day modified Rankin Scale scores. Adjusted odds ratios (aORs) and 95% CIs were obtained by logistic regression models and propensity score matching. Safety outcomes included any intracranial hemorrhage (ICH), symptomatic ICH, and mortality. Among 458 included patients, 184 (40.2%) achieved a favorable outcome (modified Rankin Scale score 0-3). There were no differences between the intravenous tirofiban group and the no tirofiban group in terms of safety and clinical outcomes (all P>0.05). Compared with the no tirofiban group, the intraarterial+intravenous tirofiban group had higher odds of 90-day modified Rankin Scale score 0 to 3 (aOR, 2.44 [95% CI, 1.30-4.64], P=0.006) and lower 3-month mortality (aOR, 0.38 [95% CI, 0.19-0.71], P=0.002) without an increase in any ICH (aOR, 0.34 [95% CI, 0.09-1.01], P=0.07) or symptomatic ICH (aOR, 0.23 [95% CI, 0.03-0.90], P=0.05). Similar results of intraarterial+intravenous tirofiban on improving clinical outcomes were detected in novel cohorts constructed by propensity score matching.

CONCLUSIONS

Intraarterial+intravenous rather than intravenous tirofiban improved clinical outcomes without increasing the frequency of symptomatic ICH among patients with basilar artery occlusion after successful endovascular treatment. Further studies are needed to delineate the roles of intraarterial+intravenous tirofiban in patients with basilar artery occlusion receiving endovascular treatment.

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

BACKGROUND

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSION

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

Revascularization of arterial occlusions in posterior circulation acute ischemic stroke

PURPOSE OF REVIEW

This review highlights the latest advancements achieved in the revascularization of arterial occlusions associated with an acute ischemic stroke affecting the posterior circulation. It delves into the frequency and outcomes based on specific arterial segments and presents current evidence supporting revascularization treatments, including intravenous thrombolysis and endovascular thrombectomy.

RECENT FINDINGS

Comprehensive evidence for treatment across major arterial segments of the posterior circulation -- vertebral artery, basilar artery, posterior cerebral artery, cerebellar arteries, and multilevel posterior occlusions -- is provided. Additionally, the latest findings from randomized clinical trials on basilar artery occlusion are explored alongside results from extensive retrospective analyses of isolated vertebral and posterior cerebral artery occlusions.

SUMMARY

Current research supports the treatment decision in acute ischemic strokes of the posterior circulation using both intravenous thrombolysis and endovascular thrombectomy. This review also emphasizes existing knowledge gaps in the management of these strokes and advocates for more randomized clinical trials, notably concerning the posterior cerebral artery (currently ongoing), isolated vertebral artery, and multilevel posterior circulation occlusions.

Enhancing the clinical value of single-phase computed tomography angiography in the assessment of collateral circulation in acute ischemic stroke: A narrative review

Acute ischemic stroke (AIS) condition assessment and clinical prognosis are significantly influenced by the compensatory state of cerebral collateral circulation. A standard clinical test known as single-phase computed tomography angiography (sCTA) is useful for quickly and accurately assessing the creation or opening of cerebral collateral circulation, which is crucial for the diagnosis and treatment of AIS. To improve the clinical application of sCTA in the clinical assessment of collateral circulation, we examine the present use of sCTA in AIS in this work.

Prognostic value of the baseline magnetic resonance score in patients with acute posterior circulation ischaemic stroke after mechanical thrombectomy

AIM

To investigate the prognostic value of the composite posterior circulation Acute Stroke Prognosis Early Computed tomography (CT) Score (ASPECTS)-Collaterals (pcASCO) score, which combines diffusion-weighted imaging (DWI) posterior circulation ASPECTS (pcASPECTS) and the magnetic resonance angiography (MRA)-collateral circulation score at baseline among patients with acute posterior circulation ischaemic stroke after mechanical thrombectomy.

MATERIALS AND METHODS

Patients with acute posterior circulation ischaemic stroke who underwent mechanical thrombectomy were analysed retrospectively. The DWI-pcASPECTS and MRA-collateral circulation score before treatment and the modified Rankin Scale (mRS) at 90 days after treatment were used as the endpoints. An mRS ≤2 was defined as a good prognosis, and an mRS ≥3 was defined as a poor prognosis. Multivariate logistic regression was used to analyse independent predictors of functional outcome 90 days after mechanical thrombectomy.

RESULTS

Mechanical thrombectomy was performed in 57 patients; 38 patients had a good prognosis, 19 patients had a poor prognosis, and 33 patients were successfully recanalised. Univariate logistic regression found that National Institute of Health Stroke Scale (NIHSS) score (OR: 1.18, p<0.001), pcASPECTS (OR: 1.91, p=0.028) and pcASCO score (OR: 0.51, p=0.001) were factors of good functional outcome. Receiver operating characteristic curve (ROC curve) analysis showed that the diagnostic efficiency of the NIHSS and pcASCO was better (AUC = 0.88, 0.83, p<0.05) than that of the pcASPECTS (AUC = 0.65). The prediction model was established by age, NIHSS, and pcASCO, and the diagnostic efficiency of the prediction model was better (AUC = 0.94).

CONCLUSIONS

The composite MR-pcASCO score can be used as an important predictor of the prognosis of patients with acute posterior circulation ischaemic stroke after mechanical thrombectomy.

Posterior circulation cerebral infarction: A review of clinical, imaging features, management, and outcomes

Objective

This narrative review discusses posterior circulation cerebral infarcts (PCCI) and provides an update given recent randomized trials in the management of basilar artery occlusion (BAO). We examine clinical characteristics, imaging protocols, management updates, and outcomes of PCCI.

Methods

The following databases were searched: MEDLINE, Scopus, Google Scholar, and Web of Science for articles on PCCI. We included randomized trials and observational studies in humans. We also reviewed relevant references from the literature identified.

Results

PCCI and BAO is associated with high morbidity and mortality. Early assessment and accurate diagnosis of PCCI remains a clinical challenge. Neuroimaging advances have improved early detection, but barriers remain due to costs and availability. Recent randomized trials provide new insights for BAO patients and support the efficacy of endovascular thrombectomy.

Discussion

PCCI requires specific diagnostic and management that is distinct from anterior circulation stroke. While further studies are needed in varied populations and in the subset of BAO patients presenting with milder deficits, growing randomized data support the treatment of BAO patients with endovascular thrombectomy.

Basilar artery occlusion: A review of clinicoradiologic features, treatment selection, and endovascular techniques

Basilar artery occlusion (BAO) is an infrequent but often fatal subtype of stroke. Predicting outcomes and selecting patients for endovascular therapy (EVT) remains challenging. Advances in neuroimaging and the development of prognostic scoring systems have augmented clinical decision-making over time. Recent randomized trials, BEST (Basilar Artery Occlusion Endovascular Intervention vs. Standard Medical Treatment), BASICS (Basilar Artery International Cooperation Study), BAOCHE (Basilar Artery Occlusion CHinese Endovascular Trial) and ATTENTION (Endovascular Treatment for Acute Basilar Artery Occlusion), compared EVT and medical management for patients with BAO. These trials yielded mixed results. The former two suggested unclear benefit while the latter two supported a benefit of EVT. While all had limitations, most providers agree caution should be exercised when excluding patients from EVT who may stand to benefit. Further studies are therefore needed to determine the effectiveness, safety, selection criteria, and optimal technical approach for EVT among patients with BAO. Hyperacute-phase advanced imaging can offer several benefits to aid decision making. It is reasonable to exclude patients with low National Institutes of Health Stroke Scale (NIHSS), large imaging-proven cores, and evidence of perforator occlusion by branch atheromatous disease. Herein, we review the clinical presentation, imaging work-up, treatments, and clinical outcomes for BAO, while highlighting knowledge gaps in treatment selection and technique.

Effect of collateral circulation in patients with multiple craniocervical artery stenoses

Based on previous findings, collateral circulation in the brain is vital in mitigating cerebral ischemia's effects and influencing stroke risk. This retrospective study examined collateral circulation, admission ischemic stroke status, and long-term recurrence in patients with multiple craniocervical artery stenoses. Consecutive symptomatic internal carotid artery (ICA) stenosis patients from the First Affiliated Hospital of Soochow University were recruited. Baseline data including medical histories and neurological function at admission were collected. Imaging techniques assessed collateral compensative capacity. Multivariate logistic regression analysis was used to investigate the association between collateral circulation and case status. A total of 559 patients with symptomatic ICA stenosis were included, among whom 153 (27.4%) had concurrent moderate to severe vertebro-basilar artery (VBA) stenosis. Dizziness, weakness/numbness, and slurring of speech were the primary symptoms in all patients. Over 36 months, 71 (12.7%) patients experienced a recurrence of acute ischemic stroke (AIS). In multivariate analysis, collateral circulation was found to be negatively associated with AIS (regional leptomeningeal collateral [rLMC] scores: OR: 0.798, 95% CI: 0.743-0.857, p < 0.001; Tan scores: OR: 0.478, 95% CI: 0.336-0.679, p < 0.001). Meanwhile, the collateral circulation scores were significantly associated with the recurrence of AIS within 3 years (rLMC scores: OR: 0.926, 95% CI: 0.860-0.997, p = 0.042; Tan scores: OR: 0.467, 95% CI: 0.306-0.712, p < 0.001). Most associations remained significant in the subgroup of patients with VBA stenosis. Favorable collateral circulation in multiple craniocervical artery stenosis patients reduced long-term ischemic event recurrence. Stratifying treatment risks is essential for optimizing outcomes.

Effect of the anastomosis between the posterior inferior cerebellar artery and the superior cerebellar artery on outcomes of acute basilar artery occlusion after endovascular treatment

BACKGROUND

The effects of secondary collateral compensation on outcomes remain unclear in patients with acute basilar artery occlusion (BAO) after endovascular treatment (EVT). This study aimed to evaluate the benefits of the anastomosis between the posterior inferior cerebellar artery (PICA) and the superior cerebellar artery (SCA) in BAO after EVT.

METHODS

This cohort study was conducted using data from the Endovascular Treatment for Acute Basilar Artery Occlusion Study Registry. Patients with acute BAO and treated with EVT were included. The primary outcome was a modified Rankin Scale score of 0-2 at 90 days. Safety outcomes included symptomatic intracerebral hemorrhage (SICH) and 90-day mortality.

RESULTS

Of the 646 patients included in the study, 196 (30.3%) patients had a PICA-SCA anastomosis. The PICA-SCA anastomosis was significantly associated with independent functional outcome at 90 days (67/196 (34.2%) vs 109/450 (24.2%), adjusted OR (aOR) 1.80 (95% CI 1.13 to 2.86), p=0.01) and was significantly associated with a decreased rate of SICH (40/442 (9.0%) vs 5/193 (2.6%), aOR 0.29 (95% CI 0.11 to 0.76), p=0.01). No significant difference was found between PICA-SCA anastomosis and 90-day mortality (219/450 (48.7%) vs 80/196 (40.8%), aOR 0.72 (95% CI 0.48 to 1.08), p=0.11). Subgroup analysis showed that the association between independent functional outcome and PICA-SCA anastomosis was strongest in patients with middle BAO (27/77 (35.1%) vs 22/118 (18.6%), aOR 2.64 (95% CI 1.13 to 6.15), p=0.03).

CONCLUSIONS

The PICA-SCA anastomosis is significantly associated with better functional outcomes in patients with acute BAO after EVT, especially in those with middle BAO.

Nomogram model of functional outcome for endovascular treatment in patients with acute basilar artery occlusion

Background and purpose

The efficacy and safety of endovascular treatment (EVT) in acute basilar artery occlusion (ABAO) has been confirmed by four randomized clinical trials. Nevertheless, the predictors of a 90-day favorable outcome after EVT have not been elucidated. We attempted to establish a nomogram for the prediction of a 90-day favorable outcome in ABAO patients with EVT.

Methods

Clinical data of ABAO patients with EVT were obtained from two nationwide clinical trial registries in China. Factors associated with a 90-day favorable outcome were screened by multivariable step-wise regression on the basis of univariable analysis. A nomogram was established to predict 90-day favorable outcome after EVT.

Results

The proportion of ABAO patients with a favorable outcome was 41.53% (157/378). Seven variables, including baseline National Institutes of Health Stroke Scale (NIHSS) <20 [odds ratio (OR): 8.330; P-value < 0.0001], posterior circulation Alberta Stroke Program Early CT (pc-ASPECT) score ≥7 (OR: 1.948; P-value = 0.0296), Pons-Midbrain Index (PMI) score < 2 (OR: 2.108; P-value = 0.0128), Posterior Circulation Collateral Score (PC-CS) ≥5 (OR: 3.288; P-value < 0.0001), local anesthesia (OR: 0.389; P-value = 0.0017), time from onset to recanalization (OTR) <330 min (OR: 2.594; P-value = 0.0013), and no occurrence of early neurological deterioration (END; OR: 0.039; P-value < 0.0001) were included into the nomogram, with C-index values of 0.8730 and 0.8857 in the training and the internal validation set, respectively.

Conclusions

The proposed nomogram provided a reliable prognostic scale, which can be employed in clinical settings for the selection and clinical management of ABAO patients.

Registration

https://www.clinicaltrials.gov, identifier: NCT03370939.

Inter-Rater Reliability of Collateral Status Assessment Based on CT Angiography: A Retrospective Study of Middle Cerebral Artery Ischaemic Stroke

The importance of assessing the collateral status (CS) in patients with ischaemic stroke (IS) has repeatedly been emphasised in clinical guidelines. Various publications offer qualitative or semiquantitative scales with gradations corresponding to the different extents of the collaterals, visualised mostly on the basis of CTA images. However, information on their inter-rater reliability is limited. Therefore, the aim of this study is to investigate the inter-rater reliability of the scales for collateral assessment. CTA images of 158 patients in the acute period of IS were used in the study. The assessment of CS was performed by two experts using three methodologies: the modified Tan scale, the Miteff scale, and the Rosenthal scale. Cohen's kappa, weighted kappa and Krippendorff's alpha were used as reliability measures. For the modified Tan scale and the Miteff and Rosenthal scales, the weighted kappa values were 0.72, 0.49 and 0.59, respectively. Although the best measure of consistency was found for the modified Tan scale, no statistically significant differences were revealed among the scales. The impact of the CS on the degree of neurological deficit at discharge was shown for the modified Tan and Rosenthal scales. In conclusion, the analysis showed a moderate inter-rater reliability of the three scales, but was not able to distinguish the best one among them.

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

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

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Risk factors and prognosis of early neurological deterioration in patients with posterior circulation cerebral infarction

BACKGROUND

The incidence, risk factors, and pathogenesis of early neurological deterioration (END) in posterior circulation stroke are still unclear. In this study, we aimed to determine the risk factors and prognosis of END in patients with acute posterior circulation cerebral infarction.

METHODS

Acute posterior circulation ischemic stroke patients who had completed neuroimaging within 72 h of onset were selected from a prospective registry study Demographic characteristics, physiological data, medical history, laboratory data, in-hospital evaluation, neurological severity and TOAST classification, treatment, and the modified Rankin Scale (mRS) score of patients were assessed. Early neurological deterioration was defined as an increase of 2 points in the National Institutes of Health Stroke Scale score between the baseline and 72 h evaluation. Favorable and poor outcomes were defined as mRSs of 02 and≥ 3, respectively, at 3 months. The incidence and risk factors were evaluated by univariate and multivariate regression analysis (step-back method).

RESULTS

The analysis included 455 subjects with an acute posterior circulation non-cardiac ischemic stroke, 330 (72.53 %) of them male, with an average age of 63.12 ( ± 10.14) years and with 47 (10.33 %) having END. The results of univariate and multivariate logistic regression analysis showed that BATMAN scores ≥ 5 (OR: 0.1, 95 % CI: 0.02-0.53, P < 0.01), large artery atherosclerosis (OR: 11.55, 95 % CI: 4.18-31.93, P < 0.01), vascular stenosis > 50 % (OR: 2.44, 95 % CI: 1.1-5.42, P = 0.029), reperfusion therapy (OR: 4.21, 95 % CI: 1.66-10.64, P < 0.01), and the distribution of pontine lesions (OR: 5.66, 95 % CI: 2.39-13.44, P < 0.01) were significantly associated with END. Patients with END had a lower rate of favorable outcomes at discharge and long-term follow-up (P < 0.001), regardless of whether they received reperfusion therapy.

CONCLUSION

The lesion distribution of the pons, the progression of temporo-occipital lobe lesions, and large arterial atherosclerosis are independent risk factors of END that might predict a poor short- and long-term prognosis.

Endovascular Therapy for Basilar Artery Occlusion: Among the First to Conceptualize, Last to Prove

In 1981, the dismal outcomes of patients with basilar artery occlusion (BAO) inspired the first reports of intra-arterial thrombolytic treatment in BAO. These reports were among the first to conceptualize that opening an artery could help patients with large vessel occlusion stroke. Whereas multiple anterior circulation LVO trials demonstrated the efficacy of endovascular therapy starting in 2014, proof of benefit for BAO was lacking until 2022. In this commentary, we reflect on how the BASICS (Basilar Artery International Cooperation Study) and BEST (Basilar Artery Occlusion: Endovascular Interventions vs Standard Medical Treatment) trials lay the foundations for clinical trials in BAO, subsequently leading to the positive results of the ATTENTION (Endovascular Treatment for Acute Basilar-Artery Occlusion) and BAOCHE (Basilar Artery Occlusion Chinese Endovascular) trials.

Collateral Status and Outcomes after Thrombectomy

Endovascular treatment (EVT) using novel mechanical thrombectomy devices has been the gold standard for patients with acute ischemic stroke caused by large vessel occlusion. Selection criteria of randomized control trials commonly include baseline infarct volume with or without penumbra evaluation. Although the collateral status has been studied and is known to modify imaging results and clinical course, it has not been commonly used for trials. Many post hoc studies, however, revealed that collateral status can help predict infarct growth, recanalization success, decreased hemorrhagic transformation after EVT, and extension of the therapeutic time window for revascularization. Here, we systematically review the recent literature and summarized the outcomes of EVT according to the collateral status of patients with acute ischemic stroke caused by large vessel occlusion. The studies reviewed indicate that pretreatment collateral circulation is associated with both clinical and imaging outcomes after EVT in patients with acute ischemic stroke due to large vessel occlusion although most patients were already selected by other imaging or clinical criteria. However, treatment decisions using information on patients' collateral status have not progressed in clinical practice. Further randomized trials are needed to evaluate the risks and benefits of EVT in consideration of collateral status.

Cerebral perfusion imaging predicts final infarct volume after basilar artery thrombectomy

OBJECTIVES

Cerebral perfusion imaging may be used to identify the ischemic core in acute ischemic stroke (AIS) patients with a large vessel occlusion of the anterior circulation; however, perfusion parameters that predict the ischemic core in AIS patients with a basilar artery occlusion (BAO) are poorly described. We determined which cerebral perfusion parameters best predict the ischemic core after successful endovascular thrombectomy (EVT) in BAO patients.

MATERIALS AND METHODS

We performed multicenter retrospective study of BAO patients with perfusion imaging before EVT and a DWI after successful EVT. The ischemic core was defined as regions on CTP, which were co-registered to the final DWI infarct. Various time-to-maximum (Tmax) and cerebral blood flow (CBF) thresholds were compared to final infarct volume to determine the best predictor of the final infarct.

RESULTS

28 patients were included in the analysis for this study. Tmax >8s (r²: 0.56; median absolute error, 16.0 mL) and Tmax >10s (r²: 0.73; median absolute error, 11.3 mL) showed the strongest agreement between the pre-EVT CTP study and the final DWI. CBF <38% (r²: 0.76; median absolute error, 8.2 mL) and CBF <34% (r²: 0.76; median absolute error, 9.1 mL) also correlated well with final infarct volume on DWI.

CONCLUSIONS

Pre-EVT CT perfusion imaging is useful to predict the final ischemic infarct volume in BAO patients. Tmax >8s and Tmax >10s were the strongest predictors of the post-EVT final infarct volume.

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

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

Occlusion type and posterior communicating artery patency may predict favorable outcome after endovascular thrombectomy in selective basilar top occlusion

Introduction

The top of the basilar artery is a five-branched junction, consisting of two superior cerebellar arteries (SCAs), two posterior cerebellar arteries (PCAs), and the basilar artery itself. This study aimed to investigate prognostic factors in patients with selective acute basilar top occlusion managed with mechanical thrombectomy, focusing on occlusion type and posterior communicating artery (PCoA) patency.

Methods

Eligible patients who underwent endovascular treatment (EVT) for acute basilar top occlusion were reviewed. Patterns of basilar top occlusion were categorized as types I–III according to whether the SCA and PCA were visible on angiography. The PCoA was categorized as hypoplastic or non-visible (type I), normal patency but non-visible PCA through PCoA flow (type II), and fetal type (type III).

Results

Good outcomes were observed in 50% (21/42) and mortality in 11.9% (5/42) of the cases at 90 days. Patients with good outcomes showed lower baseline National Institutes of Health Stroke Scale (NIHSS) score (P = 0.001) and a higher proportion of type III basilar top occlusion (P = 0.004) and type III PCoA (P = 0.001). Multivariable logistic analysis showed that baseline NIHSS score [odds ratio (OR), 0.84; 95% confidence interval (CI), 0.73–0.97; P = 0.017) and type III PCoA (OR, 21.54, 95% CI, 1.33–347.97; P = 0.031) were independent predictors of good functional outcomes.

Conclusion

A low initial NIHSS score and good PCoA patency were independent predictors of favorable clinical outcomes after EVT in patients with acute basilar top occlusion. Furthermore, the favorable outcome group showed a high proportion of type III basilar top occlusions.

Which is the most effective rescue treatment after the failure of mechanical thrombectomy for acute basilar artery occlusion?

Objective

The aim of this study was to evaluate the effectiveness and safety of rescue therapy, a therapy in which rescue devices such as balloon angioplasty, Apollo stent, Wingspan stent, Solitaire stent, or other self-expanding stents are used after the failure of mechanical thrombectomy (MT) and to determine the most effective rescue measure for acute basilar artery occlusion (BAO) after the failure of MT.

Methods

For this study, we recruited patients from the BASILAR registry. All participants were divided into three groups: the recanalized with rescue therapy group, the recanalized without rescue therapy group, and the non-recanalized group. Clinical outcomes at 90 days and 1 year were compared. The association of rescue measures with favorable outcomes (modified Rankin Scale [mRS] score of 0–3) in patients achieving successful recanalization via rescue therapy was estimated using multivariate logistic regression analyses.

Results

Among the participants, recanalization failure was found in 112 patients and successful recanalization in 473 patients, with 218 patients receiving rescue therapy and 255 patients without rescue therapy. Of these, 111 (43.5%) patients in the recanalized without rescue therapy group, 65 (29.8%) patients in the recanalized with rescue therapy group, and nine (8.0%) patients in the non-recanalized group achieved favorable outcomes at 90 days. Both the recanalization with rescue therapy and the recanalization without rescue therapy groups were associated with favorable outcomes at 90 days and 1 year compared with the non-recanalized group. Moreover, in patients receiving rescue therapy, Wingspan stents, Apollo stents, and balloon angioplasty were associated with higher rates of favorable outcomes at 90 days and 1 year than Solitaire stents.

Conclusion

Whether rescue therapy is administered or not, recanalization leads to favorable outcomes in patients with acute BAO. For acute BAO after MT failure, balloon angioplasty, Wingspan stenting, and Apollo stenting could be considered effective and safe rescue options but not Solitaire stenting.

VEGF to CITED2 ratio predicts the collateral circulation of acute ischemic stroke

Objective

The research objective was to evaluate the predicting role of the vascular endothelial growth factor to CBP/P300-interacting transactivator with Glu/Asp-rich C-terminal domain 2 Ratio (VEGF/CITED2) from peripheral blood mononuclear cells (PBMCs) in the collateral circulation of acute ischemic stroke (AIS).

Methods

In an observational study of patients with AIS, the western blot was applied to test the protein expression of VEGF and CITED2. Then, we calculated the VEGF/CITED2 and collected other clinical data. Binary logistic regression analysis between collateral circulation and clinical data was performed. Finally, receiver operating characteristic (ROC) curve analysis was used to explore the predictive value of VEGF/CITED2.

Results

A total of 67 patients with AIS were included in the study. Binary logistic regression analysis indicated the VEGF/CITED2 (OR 165.79, 95%CI 7.25–3,791.54, P = 0.001) was an independent protective factor. The ROC analyses showed an area under the ROC curve of the VEGF/CITED2 was 0.861 (95%CI 0.761–0.961). The optimal cutoff value of 1.013 for VEGF/CITED2 had a sensitivity of 89.1% and a specificity of 85.7%.

Conclusion

In patients with AIS, the VEGF/CITED2 was related to the establishment of collateral circulation. The VEGF/CITED2 is a potentially valuable biomarker for predicting collateral circulation.

Clinical trial registration

ClinicalTrials.gov, identifier: NCT05345366.

Collateral Flow in Magnetic Resonance Angiography: Prognostic Value for Vertebrobasilar Stenosis With Stroke Recurrence

Background and Purpose

Intracranial vertebrobasilar atherosclerotic stenosis (IVBAS) is a major cause of posterior circulation stroke. Some patients suffer from stroke recurrence despite receiving medical treatment. This study aimed to determine the prognostic value of a new score for the posterior communicating artery and the P1 segment of the posterior cerebral artery (PCoA-P1) for predicting stroke recurrence in IVBAS.

Methods

We retrospectively enrolled patients with severe IVBAS (70%–99%). According to the number of stroke recurrences, patients were divided into no-recurrence, single-recurrence, and multiple-recurrences groups. We developed a new 5-point grading scale, with the PCoA-P1 score ranging from 0 to 4 based on magnetic resonance angiography, in which primary collaterals were dichotomized into good (2–4 points) and poor (0 or 1 point). Stroke recurrences after the index stroke were recorded. Patients who did not experience stroke recurrence were compared with those who experienced single or multiple stroke recurrences.

Results

From January 2012 to December 2019, 176 patients were enrolled, of which 116 (65.9%) had no stroke recurrence, 35 (19.9%) had a single stroke recurrence, and 25 (14.2%) had multiple stroke recurrences. Patients with single stroke recurrence (odds ratio [OR]=4.134, 95% confidence interval [CI]=1.822–9.380, p=0.001) and multiple stroke recurrences (OR=6.894, 95% CI=2.489–19.092, p<0.001) were more likely to have poor primary collaterals than those with no stroke recurrence.

Conclusions

The new PCoA-P1 score appears to provide improve predictions of stroke recurrence in patients with IVBAS.

High neutrophil counts before endovascular treatment for acute basilar artery occlusion predict worse outcomes

Background and purpose

Ischemic stroke is related to inflammation. We investigated leukocyte counts, neutrophil counts, and NLR (neutrophil-to-lymphocyte ratio) to explore their prognostic potential and determine if high neutrophil counts before endovascular treatment (EVT) in patients with acute basilar artery occlusion (BAO) are associated with worse outcomes at 90 days post-EVT.

Methods

Leukocyte and neutrophil counts and NLR were determined in eligible patients from the Acute Basilar Artery Occlusion Study (BASILAR). Patients were divided into four groups according to leukocyte and neutrophil counts and NLR quartiles. The primary outcome was a favorable outcome based on the modified Rankin Scale (mRS: 0–3). The secondary outcome was functional independence (mRS 0–2). The safety outcome was mortality, and an unfavorable outcome was mRS 4–6. Successful reperfusion was mTICI (modified Thrombolysis in Cerebral Infarction) of 2b or 3. All the data were collected within 90 days after EVT.

Results

We enrolled 586 patients in the study. The leukocyte and neutrophil counts and NLR were significantly associated with clinical outcomes in all patients though no effects were seen in some intervals. Of these three parameters, the neutrophil count had the most significant impact, negatively affecting the outcome. The findings were similar in patients who were successfully recanalized.

Conclusion

Higher neutrophil counts predicted worse clinical outcomes 90 days after EVT. This finding supports the deleterious role of inflammation in patients with acute BAO despite EVT or successful recanalization.

Locked-in syndrome responding to endovascular treatment

Background

Locked-in syndrome (LiS) is a rare and devastating condition in patients with acute basilar artery occlusion. However, the benefits of endovascular treatment (EVT) for LiS remain unclear.

Objective

To assess the outcomes associated with EVT and identify the factors associated with outcomes of LiS.

Methods

We used the data of the Endovascular Treatment for Acute Basilar Artery Occlusion Study Registry (BASILAR) from 47 tertiary stroke centers in China. The included patients had LiS and received EVT or standard medical treatment (SMT) alone. The primary outcome was improvement in the modified Rankin Scale (mRS) score at 90 days.

Results

Among the 120 patients with LiS, 92 (76.7%) received EVT and 28 (23.3%) received SMT. Compared with SMT, EVT was associated with improved mRS score (common OR (cOR)=2.68 (95% CI 1.16 to 6.20); p=0.02) and decreased mortality (aOR=0.35 (95% CI 0.13 to 0.90); p=0.03). Moreover, the benefit of EVT for LiS was sustained for at least 1 year (p=0.008). Higher baseline posterior circulation Alberta Stroke Prognosis Early CT Score (pc-ASPECTS, aOR=2.04 (95% CI 1.34 to 3.10); p<0.001) and absence of pneumonia (aOR=0.26 (95% CI 0.08 to 0.90); p=0.03) were significantly associated with favorable functional outcome at 90 days in patients who received EVT, while lower pc-ASPECTS (aOR=0.52 (95% CI 0.36 to 0.76); p<0.001) was associated with increased 90-day mortality.

Conclusions

This study found that EVT was associated with favorable functional outcomes and decreased mortality among patients with LiS. Baseline pc-ASPECTS and pneumonia were independent predictors of outcomes.

Outcomes of Endovascular Therapy in Young Patients with Acute Basilar Artery Occlusion: A Substudy of BASILAR Registry Study

INTRODUCTION

This study aimed to investigate clinical outcomes in young patients with basilar artery occlusion (BAO) receiving endovascular therapy (EVT).

METHODS

Consecutive patients with BAO within 24 h who underwent EVT from the BASILAR Registry study were enrolled. We compared clinical outcomes of young patients (aged 18-55 years) with older patients (aged > 55 years) with stroke due to BAO at 90 days and 1 year after EVT. The primary and secondary outcomes were improvement in modified Rankin scale scores (mRS) at 90 days and either favorable (mRS 0-3) or mortality at 90 days, respectively.

RESULTS

A total of 646 patients were included, of which 152 (23.53%) were aged 18-55 years. Dyslipidemia (42.11% vs. 30.36%, p = 0.007) and good collateral circulation (60.52% vs. 46.35%, p = 0.002) were more frequent in young patients than older. Stroke etiologies in young patients included large artery atherosclerosis (67.11%), cardioembolism (15.13%), and vessel dissection (5.26%). Young patients were associated with better prognosis (mRS: adjusted odds ratio (aOR) 1.73; 95% confidence interval [CI] 1.21-2.48; mRS 0-3: aOR 1.60; 95% CI 1.01-2.54; mortality: aOR 0.60; 95% CI 0.38-0.93) at 90 days. Baseline National Institutes of Health Stroke Scale (NIHSS) score, posterior circulation Alberta Stroke Program Early Computed Tomography Score (pc-ASPECTS), and sex were independent predictors of clinical outcomes of young patients at 90 days after EVT.

CONCLUSION

Young patients with BAO had better clinical outcomes after EVT than old patients. Predictors of clinical outcomes in young patients undergoing EVT included baseline NIHSS score, pc-ASPECTS, and sex.

TRIAL REGISTRATION

Clinical Trial Registration-URL: ChiCTR180001475 ( www.chictr.org.cn ).

Treatment of posterior circulation stroke: acute management and secondary prevention

One-fifth of strokes occur in the territory of the posterior circulation, but their management, particularly acute reperfusion therapy and neurointervention procedures for secondary prevention, has received much less attention than similar interventions for the anterior circulation. In this review, we overview the treatment of posterior circulation stroke, including both interventions in the acute setting and secondary prevention. We focus on areas in which the management of posterior circulation stroke differs from that of stroke in general and highlight recent advances.

Effectiveness of acute revascularization of posterior circulation strokes remains in large parts unproven. Thrombolysis seems to have similar benefits and lower hemorrhage risks than in the anterior circulation. The recent ATTENTION and BAOCHE trials have demonstrated that thrombectomy benefits strokes with basilar artery occlusion, but its effect on other posterior occlusion sites remains uncertain. Ischemic and hemorrhagic space-occupying cerebellar strokes can benefit from decompressive craniectomy.

Secondary prevention of posterior circulation strokes includes aggressive treatment of cerebrovascular risk factors with both drugs and lifestyle interventions and short-term dual anti-platelet therapy. Randomized controlled trial (RCT) data suggest basilar artery stenosis is better treated with medical therapy than stenting, which has a high peri-procedural risk. Limited data from RCTs in stenting for vertebral stenosis suggest that intracranial stenosis is currently best treated with medical therapy alone; the situation for extracranial stenosis is less clear where stenting for symptomatic stenosis is an option, particularly for recurrent symptoms; larger RCTs are required in this area.

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

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

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Etiology of Large Vessel Occlusion Posterior Circulation Stroke: Results of the MR CLEAN Registry

BACKGROUND

In patients with large vessel occlusion stroke of the anterior circulation, underlying cause is a determinant of outcome. Whether this is the case for posterior circulation large vessel occlusion stroke has yet to be determined. We aimed to report on cause in patients with posterior circulation stroke treated with endovascular thrombectomy and to analyze the association with functional outcome.

METHODS

We used data of patients with posterior circulation stroke included in the MR CLEAN (Multicenter Randomized Controlled Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands) registry, a prospective multicenter observational study, between 2014 and 2018. Stroke cause was categorized into large artery atherosclerosis (LAA), cardioembolism, arterial dissection, embolic stroke of undetermined source (ESUS), other determined cause, or undetermined cause. For primary analysis on the association between cause and outcome, we used multivariable ordinal logistic regression analysis to estimate the adjusted common odds ratio for a shift towards a better functional outcome on the modified Rankin Scale at 90 days with LAA as a reference group. Secondary outcomes included favorable functional outcome (modified Rankin Scale score 0-3), National Institutes of Health Stroke Scale score at 24 to 48 hours, reperfusion on digital subtraction angiography, and stroke progression.

RESULTS

Of 264 patients with posterior circulation stroke, 84 (32%) had LAA, 48 (18%) cardioembolism, 31 (12%) dissection, and 14 (5%) ESUS. Patients with a dissection were younger (48 [interquartile range, 43-60] years) and had a lower National Institutes of Health Stroke Scale at baseline (12 [interquartile range, 6-31]) than patients with other cause. Functional outcome was better for patients with cardioembolism and ESUS compared to LAA (modified Rankin Scale adjusted common odds ratio, 2.4 [95% CI, 1.1-5.2], respectively adjusted common odds ratio, 3.1 [95% CI, 1.0-9.3]). Patients with a dissection had a lower chance of successful reperfusion compared with LAA (adjusted odds ratio, 0.20 [95% CI, 0.06-0.70]).

CONCLUSIONS

Unlike the anterior circulation, most frequent cause in our posterior large vessel occlusion stroke cohort is LAA followed by cardioembolism, dissection, and ESUS. Patients with cardioembolism and ESUS have a better prognosis for functional outcome after endovascular thrombectomy than patients with LAA.

Predictors and Outcomes of Salvaging the Corticospinal Tract After Thrombectomy in Basilar Artery Occlusion Stroke

Background

Regional eloquence of brainstem structures may contribute to neurological status in basilar artery occlusion (BAO) stroke. The corticospinal tract (CST) which is vulnerable to BAO is important for motor activity. This study investigated the impact of CST salvage on outcomes and its associated factors in patients with BAO treated with thrombectomy.

Methods

We retrospectively investigated 88 patients with BAO admitted ≤24 h after onset and presented with motor deficits and who underwent thrombectomy. Patients with a pre-stroke modified Rankin Scale (mRS) score of 4–5 who did not undergo baseline brain computed tomography angiography were excluded. CST salvage was evaluated using follow-up imaging (magnetic resonance imaging [MRI] or computed tomography when MRI was not available) after thrombectomy. A good outcome was defined as a 3-month mRS score of ≤2 or 3 if a patient's pre-stroke mRS score was 3. The associations between CST salvage and outcomes and clinical parameters were analyzed using logistic regression analyses.

Results

Thirty-nine (44.3%) patients had CST salvage and the same number of patients had good outcomes. CST salvage was independently associated with a good outcome [adjusted odds ratio (aOR): 18.52, 95% confidence interval (CI): 4.31–79.67, p &lt; 0.001]. After adjusting for confounders, atrial fibrillation (aOR: 3.92, 95% CI: 1.18–13.00, p = 0.026), location of occlusion (mid-BAO; aOR: 0.21, 95% CI: 0.06–0.72, p = 0.013), length of occlusion (involved segment of BAO &lt;2; aOR: 4.77, 95% CI: 1.30–17.59, p = 0.019), and onset-to-puncture-time ≤180 min (aOR: 4.84, 95% CI: 1.13–20.75, p = 0.034) were significantly associated with CST salvage.

Conclusion

CST salvage was associated with good functional outcomes in patients with BAO treated with thrombectomy. The presence of atrial fibrillation, location and length of BAO may predict CST salvage after thrombectomy, and rapid treatment with thrombectomy may protect this eloquent tract in these patients.

Neutrophil Count Predicts Malignant Cerebellar Edema and Poor Outcome in Acute Basilar Artery Occlusion Receiving Endovascular Treatment: A Nationwide Registry-Based Study

Background

Acute basilar artery occlusion (ABAO) is known to have a poor outcome with a high rate of morbidity and mortality despite endovascular treatment (EVT), highlighting the necessities of exploring factors to limit the efficacy of EVT in these patients. Cerebellar infarctions in ABAO might progress to malignant cerebellar edema (MCE), a life-threatening complication after reperfusion, posing a secondary injury to the brainstem by mass effects. Therefore, the present research aimed to explore the impacts of MCE on a long-term outcome and investigate the prognostic factors for MCE among ABAO after EVT.

Methods

In the national BASILAR registry, a total of 329 ABO patients with cerebellar infarctions treated by EVT met the inclusion criteria. The presence of MCE defined by the Jauss scale ≥4 points, was evaluated on the computed tomography performed 72 h after EVT. The adjusted odds ratio and 95% CI were obtained by logistic regression models. A favorable outcome was defined as a 90-day modified Rankin Scale score of 0-3.

Results

MCE was statistically associated with the decreased incidence of a favorable outcome [adjusted odds ratio, 0.35(95% CI, 0.18-0.68), P=0.002]. The baseline National Institutes of Health Stroke Scale score, collateral circulation, neutrophil count at admission, and recanalization status were predictors for MCE and a favorable functional status at 90 days (all P<0.05). Among all inflammatory factors, the neutrophil count achieved the highest accuracy, sensitivity, and specificity for MCE. Adding the neutrophil count status into the baseline model obviously enhanced its prediction ability for MCE and favorable outcome by increasing the area under curve and achieving both net reclassification and integrated discrimination improvement (all P<0.05). Mediation analysis indicated that MCE mediated the association between the increased neutrophil count and worse functional outcome (P=0.026).

Discussion

MCE acted essential roles in worsening prognosis for ABAO after EVT. A high neutrophil count at admission was linked to MCE and a poor outcome among ABAO patients, which could be further incorporated into the clinical decision-making system and guide immunomodulation therapy.

Effect of Imaging Markers on Reperfusion Therapy in Basilar Artery Occlusion

Objective

We aimed to investigate the effectiveness of endovascular therapy (EVT) versus intravenous thrombolysis (IVT) in patients with basilar artery occlusion (BAO), based on the information of advanced imaging.

Methods

We analyzed data of stroke patients with radiologically confirmed BAO within 24 hours. BAO subjects were categorized into “top‐of‐the‐basilar” syndrome (TOBS) and other types. An initial infarct size of <70ml and a ratio of ischemic tissue to infarct volume of ≥1.8 was defined as “target mismatch.” The primary outcome was a good outcome, defined as a modified Rankin Scale score of 0 to 3 at 3 months. Propensity score adjustment and inverse probability of treatment weighting (IPTW) propensity score methods were used.

Results

Among 474 BAO patients, 93 (19.6%) were treated with IVT prior to EVT, 91 (19.2%) were treated with IVT alone, 95 (20.0%) were treated with EVT alone, and 195 (41.1%) were treated with antithrombotic therapy. In IPTW analyses, we found no benefit of EVT over IVT for good outcome in either TOBS patients (odds ratio = 1.08, 95% confidence interval [CI] = 0.88–1.31) or those with other types (odds ratio = 1.13, 95% CI = 0.94–1.36). However, in patients with other types, if there existed a target mismatch, EVT was independently related to good outcome (odds ratio = 1.46, 95% CI = 1.17–1.81).

Interpretation

The “target mismatch profile” seems to be a possible candidate selection standard of EVT for those with other types of BAO. Future studies should separate TOBS from other types of BAO, and try to use advanced imaging. ANN NEUROL 2022;92:97–106

Effect of first pass reperfusion on outcome in patients with posterior circulation ischemic stroke

BACKGROUND

First pass reperfusion (FPR), that is, excellent reperfusion (expanded treatment in cerebral ischemia (eTICI) 2C-3) in one pass, after endovascular treatment (EVT) of an occluded artery in the anterior circulation, is associated with favorable clinical outcome, even when compared with multiple pass excellent reperfusion (MPR). In patients with posterior circulation ischemic stroke (PCS), the same association is expected, but currently unknown. We aimed to assess characteristics associated with FPR and the influence of FPR versus MPR on outcomes in patients with PCS.

METHODS

We used data from the MR CLEAN Registry, a prospective observational study. The effect of FPR on 24-hour National Institutes of Health Stroke Scale (NIHSS) score, as percentage reduction, and on modified Rankin Scale (mRS) scores at 3 months, was tested with linear and ordinal logistic regression models.

RESULTS

Of 224 patients with PCS, 45 patients had FPR, 47 had MPR, and 90 had no excellent reperfusion (eTICI <2C). We did not find an association between any of the patient, imaging, or treatment characteristics and FPR. FPR was associated with better NIHSS (-45% (95% CI: -65% to -12%)) and better mRS scores (adjusted common odds ratio (acOR): 2.16 (95% CI: 1.23 to 3.79)) compared with no FPR. Outcomes after FPR were also more favorable compared with MPR, but the effect was smaller and not statistically significant (NIHSS: -14% (95% CI: -51% to 49%), mRS acOR: 1.50 (95% CI: 0.75 to 3.00)).

CONCLUSIONS

FPR in patients with PCS is associated with favorable clinical outcome in comparison with no FPR. In comparison with MPR, the effect of FPR was no longer statistically significant. Nevertheless, our data support the notion that FPR should be the treatment target to pursue in every patient treated with EVT.

New imaging score for outcome prediction in basilar artery occlusion stroke

OBJECTIVE

In ischemic posterior circulation stroke, the utilization of standardized image scores is not established in daily clinical practice. We aimed to test a novel imaging score that combines the collateral status with the rating of the posterior circulation Acute Stroke Prognosis Early CT score (pcASPECTS). We hypothesized that this score (pcASCO) predicts functional outcome and malignant cerebellar edema (MCE).

METHODS

Ischemic stroke patients with acute BAO who received multimodal-CT and underwent thrombectomy on admission at two comprehensive stroke centers were analyzed. The posterior circulation collateral score by van der Hoeven et al was added to the pcASPECTS to define pcASCO as a 20-point score. Multivariable logistic regression analyses were performed to predict functional independence at day 90, assessed using modified Rankin Scale scores, and occurrence of MCE in follow-up CT using the established Jauss scale score as endpoints.

RESULTS

A total of 118 patients were included, of which 84 (71%) underwent successful thrombectomy. Based on receiver operating characteristic curve analysis, pcASCO ≥ 14 classified functional independence with higher discriminative power (AUC: 0.83, 95%CI: 0.71-0.91) than pcASPECTS (AUC: 0.74). In multivariable logistic regression analysis, pcASCO was significantly and independently associated with functional independence (aOR: 1.91, 95%CI: 1.25-2.92, p = 0.003), and MCE (aOR: 0.71, 95%CI: 0.53-0.95, p = 0.02).

CONCLUSION

The pcASCO could serve as a simple and feasible imaging tool to assess BAO stroke patients on admission and might be tested as a complementary tool to select patients for thrombectomy in uncertain situations, or to predict clinical outcome.

KEY POINTS

• The neurological assessment of basilar artery occlusion stroke patients can be challenging and there are yet no validated imaging scores established in daily clinical practice. • The pcASCO combines the rating of early ischemic changes with the status of the intracranial posterior circulation collaterals. • The pcASCO showed high diagnostic accuracy to predict functional outcome and malignant cerebellar edema and could serve as a simple and feasible imaging tool to support treatment selection in uncertain situations, or to predict clinical outcome.

Posterior Circulation Stroke: Coma (More Than Time) is Brain

BACKGROUND AND PURPOSE

Contrary to anterior circulation, the legitimacy of endovascular treatment in posterior circulation stroke is still being questioned. Finding reliable prognostic factors and determining how patient selection should be done has become top priority.

METHODS

Observational and retrospective study from two Portuguese hospitals, including all consecutive patients with posterior circulation occlusions who underwent thrombectomy between January 1st 2015 and December 31st 2019.

RESULTS

Out of a total of 126 patients, the median age was 74 (IQR 61-80) and 39.7% were female. A good clinical outcome (mRS ≤2) was associated with a lower incidence of coma (24,2% vs 66,7%, p < 0,001) and of sudden onset coma (3% vs 18%,=0,04), a lower NIHSS at admission (14 vs 19, p < 0,001), a higher pc-ASPECTS at admission (10 vs 9, p < 0,001) and at 24 h (8 vs 6, p < 0,001) and a higher BATMAN score (7 vs 6, p = 0,017). Differences in the times of symptom-onset-to-recanalization (496 vs 536, p = 0,19) and symptom-onset-to-coma (130 vs 195, p = 0,52) were not remarkable. When excluding NIHSS and pc-ASPECTS at 24 h, coma (p = 0,003; OR=0,22; 95% CI: 0,08-0,59) and the pc-ASPECTS at admission (p = 0,037; OR=1,63; 95% CI: 1,03-2,57) become independent predictors of good outcome.

CONCLUSIONS

In strokes from the posterior circulation, coma, more than time, appears to be an important prognostic factor. The BATMAN and the pc-ASPECTS scores were also associated with clinical outcome and coma.

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

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

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

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

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

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

IMPORTANCE

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

OBJECTIVES

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

DESIGN, SETTING, AND PARTICIPANTS

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

EXPOSURES

EVT with SMT vs SMT alone.

MAIN OUTCOMES AND MEASURES

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

RESULTS

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

CONCLUSIONS AND RELEVANCE

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

Endovascular Treatment for Posterior Circulation Stroke in Routine Clinical Practice: Results of the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands Registry

BACKGROUND AND PURPOSE

The benefit of endovascular treatment (EVT) for posterior circulation stroke (PCS) remains uncertain, and little is known on treatment outcomes in clinical practice. This study evaluates outcomes of a large PCS cohort treated with EVT in clinical practice. Simultaneous to this observational study, several intervention centers participated in the BASICS trial (Basilar Artery International Cooperation Study), which tested the efficacy of EVT for basilar artery occlusion in a randomized setting. We additionally compared characteristics and outcomes of patients treated outside BASICS in trial centers to those from nontrial centers.

METHODS

We included patients with PCS from the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands Registry: a prospective, multicenter, observational study of patients who underwent EVT in the Netherlands between 2014 and 2018. Primary outcome was a score of 0 to 3 on the modified Rankin Scale at 90 days. Secondary outcomes included reperfusion status and symptomatic intracranial hemorrhage. For outcome comparison between patients treated in trial versus nontrial centers, we used ordinal logistic regression analysis.

RESULTS

We included 264 patients of whom 135 (51%) had received intravenous thrombolysis. The basilar artery was most often involved (77%). Favorable outcome (modified Rankin Scale score 0-3) was observed in 115/252 (46%) patients, and 109/252 (43%) patients died. Successful reperfusion was achieved in 178/238 (75%), and symptomatic intracranial hemorrhage occurred in 9/264 (3%). The 154 nontrial patients receiving EVT in BASICS trial centers had similar characteristics and outcomes as the 110 patients treated in nontrial centers (modified Rankin Scale adjusted cOR: 0.77 [95% CI, 0.5-1.2]).

CONCLUSIONS

Our study shows that high rates of favorable clinical outcome and successful reperfusion can be achieved with EVT for PCS, despite high mortality. Characteristics and outcomes of patients treated in trial versus nontrial centers were similar indicating that our cohort is representative of clinical practice in the Netherlands. Randomized studies using modern treatment approaches are needed for further insight in the benefit of EVT for PCS.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Aspiration Versus Stent Retriever Thrombectomy for Posterior Circulation Stroke

BACKGROUND AND PURPOSE

Whereas a clear benefit of endovascular treatment for anterior circulation stroke has been established, randomized trials assessing the posterior circulation have failed to show efficacy. Previous studies in anterior circulation stroke suggest that advanced thrombectomy devices were of great importance in achieving clinical benefit. Little is known about the effect of thrombectomy techniques on outcomes in posterior circulation stroke. In this study, we compare first-line strategy of direct aspiration to stent retriever thrombectomy for posterior circulation stroke.

METHODS

We analyzed data of patients with a posterior circulation stroke who were included in the Multicentre Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands Registry between March 2014 and December 2018, a prospective, nationwide study, in which data were collected from consecutive patients who underwent endovascular treatment for ischemic stroke in the Netherlands. We compared patients who underwent first-line aspiration versus stent retriever thrombectomy. Primary outcome was functional outcome according to the modified Rankin Scale. Secondary outcomes were reperfusion grade, complication rate, and procedure duration. Associations between thrombectomy technique and outcome measures were estimated with multivariable ordinal logistic regression analyses.

RESULTS

Overall, 71 of 205 patients (35%) were treated with aspiration, and 134 (65%) with stent retriever thrombectomy. Patients in the aspiration group had a lower pc-ASPECTS on baseline computed tomography, and general anesthesia was more often applied in this group. First-line aspiration was associated with better functional outcome compared with stent retriever thrombectomy (adjusted common odds ratio for a 1-point improvement on the modified Rankin Scale 1.94 [95% CI, 1.03-3.65]). Successful reperfusion (extended Thrombolysis in Cerebral Infarction ≥2B) was achieved more often with aspiration (87% versus 73%, P=0.03). Symptomatic hemorrhage rates were comparable (3% versus 4%). Procedure times were shorter in the aspiration group (49 versus 69 minutes P<0.001).

CONCLUSIONS

In this retrospective nonrandomized cohort study, our findings suggest that first-line aspiration is associated with a shorter procedure time, better reperfusion, and better clinical outcome than stent retriever thrombectomy in patients with ischemic stroke based on large vessel occlusion in the posterior circulation.

Hemodynamic Disturbances in Posterior Circulation Stroke: 4D Flow Magnetic Resonance Imaging Added to Computed Tomography Angiography

Objective: A clinically feasible, non-invasive method to quantify blood flow, hemodynamics, and collateral flow in the vertebrobasilar arterial tree is missing. The objective of this study was to evaluate the feasibility of quantifying blood flow and blood flow patterns using 4D flow magnetic resonance imaging (MRI) in consecutive patients after an ischemic stroke in the posterior circulation. We also explore if 4D-flow, analyzed in conjunction with computed tomography angiography (CTA), has potential as a diagnostic tool in posterior circulation stroke. Methods: Twenty-five patients (mean age 62 years; eight women) with acute ischemic stroke in the posterior circulation were investigated. At admission, all patients were examined with CTA followed by MRI (4D flow MRI and diffusion-weighted sequences) at median 4 days after the presenting event. Based on the classification of Caplan, patients were divided into proximal/middle (n = 16) and distal territory infarcts (n = 9). Absolute and relative blood flow rates were calculated for internal carotid arteries (ICA), vertebral arteries (VA), basilar artery (BA), posterior cerebral arteries (P1 and P2), and the posterior communicating arteries (Pcom). In a control group consisting of healthy elderly, the 90th and 10th percentiles of flow were calculated in order to define normal, increased, or decreased blood flow in each artery. "Major hemodynamic disturbance" was defined as low BA flow and either low P2 flow or high Pcom flow. Various minor hemodynamic disturbances were also defined. Blood flow rates were compared between groups. In addition, a comprehensive analysis of each patient's blood flow profile was performed by assessing relative blood flow rates in each artery in conjunction with findings from CTA. Results: There was no difference in total cerebral blood flow between patients and controls [604 ± 117 ml/min vs. 587 ± 169 ml/min (mean ± SD), p = 0.39] or in total inflow to the posterior circulation (i.e., the sum of total VA and Pcom flows, 159 ± 63 ml/min vs. 164 ± 52 ml/min, p = 0.98). In individual arteries, there were no significant differences between patients and controls in absolute or relative flow. However, patients had larger interindividual relative flow variance in BA, P1, and P2 (p = 0.01, <0.01, and 0.02, respectively). Out of the 16 patients that had proximal/middle territory infarcts, nine had CTA findings in VA and/or BA generating five with major hemodynamic disturbance identified with 4D flow MRI. For those without CTA findings, seven had no or minor 4D flow MRI hemodynamic disturbance. Among nine patients with distal territory infarcts, one had major hemodynamic disturbances, while the remaining had minor disturbances. Conclusion: 4D flow MRI contributed to the identification of the patients who had major hemodynamic disturbances from the vascular pathologies revealed on CTA. We thus conclude that 4D flow MRI could add valuable hemodynamic information when used in conjunction with CTA.