Analysis of relevant factors affecting the prognosis of mechanical thrombectomy in patients with acute posterior circulation large vessel occlusion cerebral infarction

OBJECTIVE

To explore the factors affecting the prognosis of patients with acute posterior circulation large vessel occlusion cerebral infarction (PCO) after mechanical thrombectomy.

METHOD

A retrospective study was conducted on a total of 58 patients who received thrombectomy and presented within 24 h of onset with PCO from 31 September 2020 to 31 December 2022. They were divided into two groups based on a 90-day mRS score(The mRS score of 0-3 was defined as a good prognosis, and 4-6 was defined as a poor prognosis).A univariate analysis was conducted on baseline data such as age and patient past medical history, as well as extended cerebral infarction thrombolysis grade (eTICI grade) and incidence of symptomatic intracranial hemorrhage (sICH) after surgery, for the groups with good prognosis and poor prognosis. Factors affecting the 90-day prognosis of patients were also analyzed in subgroups.

RESULTS

The preoperative National Institutes of Health Stroke Scale (NIHSS score)[21(12-35) vs 35(35-35)], postoperative 24-h NIHSS score[13(8-22) vs 35(35-35)], computed tomography (CT)[9(9-10) vs 6.5(6-7.75)] and computed tomography (CTP) brain blood volume (CBV)[9(8-10) vs 4(2-7.75)], cerebral blood flow (CBF)[7(4.5-9) vs 2(1-4)], time to peak (Tmax) [1(0.5-4) vs 0(0-1.75)] imaging of the posterior circulation Alberta stroke project early CT score (pc-ASPECTS score), Different locations of vascular occlusion, time from femoral artery puncture to vascular recanalization(64.96 ± 33.47 vs 92.68 ± 53.17). The differences in the conversion rate of postoperative intracranial hemorrhage(0 vs 16.1%) and the incidence of sICH(0 vs 12.9%) were statistically significant (P < 0.05). The subgroup analysis showed that vascular occlusion site, preoperative CBV pc-ASPECTS scores, and postoperative sICH occurrence were related to the 90-day prognosis of patients, and the differences were statistically significant (P < 0.05).

CONCLUSIONS

Some factors that can affect the prognosis of mechanical thrombectomy in patients with acute posterior circulation large vessel occlusion cerebral infarction. Preoperative clinical symptoms and imaging evaluation have certain evaluation values for prognosis.

Bailout intracranial angioplasty or stenting following thrombectomy for acute large vessel occlusion in China (ANGEL-REBOOT): a multicentre, open-label, blinded-endpoint, randomised controlled trial

BACKGROUND

Unsuccessful recanalisation or reocclusion after thrombectomy is associated with poor outcomes in patients with large vessel occlusion (LVO) acute ischaemic stroke (LVO-AIS). Bailout angioplasty or stenting (BAOS) could represent a promising treatment for these patients. We conducted a randomised controlled trial with the aim to investigate the safety and efficacy of BAOS following thrombectomy in patients with LVO.

METHODS

ANGEL-REBOOT was an investigator-initiated, multicentre, prospective, randomised, controlled, open-label, blinded-endpoint clinical trial conducted at 36 tertiary hospitals in 19 provinces in China. Participants with LVO-AIS 24 h after symptom onset were eligible if they had unsuccessful recanalisation (expanded Thrombolysis In Cerebral Infarction score of 0-2a) or risk of reocclusion (residual stenosis >70%) after thrombectomy. Eligible patients were randomly assigned by the minimisation method in a 1:1 ratio to undergo BAOS as the intervention treatment, or to receive standard therapy (continue or terminate the thrombectomy procedure) as a control group, both open-label. In both treatment groups, tirofiban could be recommended for use during and after the procedure. The primary outcome was the change in modified Rankin Scale score at 90 days, assessed in the intention-to-treat population. Safety outcomes were compared between groups. This trial was completed and registered at ClinicalTrials.gov (NCT05122286).

FINDINGS

From Dec 19, 2021, to March 17, 2023, 706 patients were screened, and 348 were enrolled, with 176 assigned to the intervention group and 172 to the control group. No patients withdrew from the trial or were lost to follow-up for the primary outcome. The median age of patients was 63 years (IQR 55-69), 258 patients (74%) were male, and 90 patients (26%) were female; all participants were Chinese. After random allocation, tirofiban was administered either intra-arterially, intravenously, or both in 334 [96%] of 348 participants. No between-group differences were observed in the primary outcome (common odds ratio 0·86 [95% CI 0·59-1·24], p=0·41). Mortality was similar between the two groups (19 [11%] of 176 vs 17 [10%] of 172), but the intervention group showed a higher risk of symptomatic intracranial haemorrhage (eight [5%] of 175 vs one [1%] of 169), parenchymal haemorrhage type 2 (six [3%] of 175 vs none in the control group), and procedure-related arterial dissection (24 [14%] of 176 vs five [3%] of 172).

INTERPRETATION

Among Chinese patients with unsuccessful recanalisation or who are at risk of reocclusion after thrombectomy, BAOS did not improve clinical outcome at 90 days, and incurred more complications compared with standard therapy. The off-label use of tirofiban might have affected our results and their generalisability, but our findings do not support the addition of BAOS for such patients with LVO-AIS.

FUNDING

Beijing Natural Science Foundation, National Natural Science Foundation of China, National Key R&D Program Beijing Municipal Administration of Hospitals Incubating Program, Shanghai HeartCare Medical Technology, HeMo (China) Bioengineering, Sino Medical Sciences Technology.

Randomised study of bailout intracranial angioplasty following thrombectomy for acute large vessel occlusion (ANGEL-REBOOT): protocol of a multicentre randomised controlled trial

RATIONALE

Unsuccessful thrombectomy of acute large vessel occlusions (LVOs) has been associated with unfavourable outcomes. Multiple randomised controlled trials (RCTs) have reported a failure rate of 12%-41% for thrombectomy procedures. Various factors contribute to failed thrombectomy, including technical difficulties in accessing the occlusion, unsuccessful thrombus retrieval, thrombotic reocclusion and pre-existing intracranial atherosclerotic stenosis. Although some studies have explored balloon dilation or permanent stenting as rescue intracranial angioplasty for failed thrombectomy in individual cases, there is currently no evidence from RCTs on this specific topic.

AIM

To evaluate the potential superiority of bailout angioplasty over standard treatment in cases of unsuccessful recanalisation (eTICI 0 to 2a) or residual severe stenosis (>70%) after thrombectomy in acute LVO patients within 24 hours of stroke onset.

DESIGN

This study is a multicentre, prospective, randomised, controlled clinical trial designed by investigators. It compares bailout angioplasty with standard therapy and follows an open-label treatment approach while maintaining a blinded outcome assessment (PROBE design). Our objective is to allocate 348 patients in a 1:1 ratio to either receive bailout angioplasty as an intervention or standard therapy as a control, following unsuccessful thrombectomy.

OUTCOME

The main measure of interest is the modified Rankin Scale (mRS) Score, which will be assessed in a blinded manner at 90 (±14) days following randomisation. The primary effect size will be determined using ordered logistic regression to calculate the common OR, representing the shift on the six-category mRS Scale at the 90-day mark. Additionally, the safety outcomes will be evaluated, including symptomatic intracranial haemorrhage within 18-36 hours, severe procedure-related complications and mortality within 90 (±14) days, among others.

DISCUSSION

The ANGEL-REBOOT study aims to generate substantial evidence regarding the efficacy and safety of bailout intracranial angioplasty as a treatment option for patients with LVO who have experienced unsuccessful thrombectomy.

TRIAL REGISTRATION NUMBER

NCT05122286.

Advances in mechanical thrombectomy for acute ischaemic stroke

Mechanical thrombectomy is a ground breaking treatment for acute ischaemic stroke caused by occlusion of a large vessel. Its efficacy over intravenous thrombolysis has been proven in multiple trials with a lower number needed to treat than percutaneous coronary intervention for acute myocardial infarction. However, access to this key treatment modality remains limited with a considerable postcode lottery across the UK and many parts of the world. The evidence base for mechanical thrombectomy dates back to 2015. Since then, there have been important advances in establishing and widening the criteria for treatment. This narrative review aims to summarise the current evidence base and latest advances for physicians and academics with an interest in recanalisation treatments for acute ischaemic stroke.

DWI-Based Radiomics Predicts the Functional Outcome of Endovascular Treatment in Acute Basilar Artery Occlusion

BACKGROUND AND PURPOSE

Endovascular treatment is a reference treatment for acute basilar artery occlusion (ABAO). However, no established and specific methods are available for the preoperative screening of patients with ABAO suitable for endovascular treatment. This study explores the potential value of DWI-based radiomics in predicting the functional outcomes of endovascular treatment in ABAO.

MATERIALS AND METHODS

Patients with ABAO treated with endovascular treatment from the BASILAR registry (91 patients in the training cohort) and the hospitals in the Northwest of China (31 patients for the external testing cohort) were included in this study. The Mann-Whitney U test, random forests algorithm, and least absolute shrinkage and selection operator were used to reduce the feature dimension. A machine learning model was developed on the basis of the training cohort to predict the prognosis of endovascular treatment. The performance of the model was evaluated on the independent external testing cohort.

RESULTS

A subset of radiomics features (n = 6) was used to predict the functional outcomes in patients with ABAO. The areas under the receiver operating characteristic curve of the radiomics model were 0.870 and 0.781 in the training cohort and testing cohort, respectively. The accuracy of the radiomics model was 77.4%, with a sensitivity of 78.9%, specificity of 75%, positive predictive value of 83.3%, and negative predictive value of 69.2% in the testing cohort.

CONCLUSIONS

DWI-based radiomics can predict the prognosis of endovascular treatment in patients with ABAO, hence allowing a potentially better selection of patients who are most likely to benefit from this treatment.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

Predictors of Functional Outcome and Mortality in Endovascular Treatment for Acute Basilar Artery Occlusion: A Single-Centre Experience

Background and Purpose: The objective of this study was to identify prognostic factors of endovascular treatment in patients with acute basilar artery occlusion and add evidence about the efficacy and safety of endovascular treatment for acute basilar artery occlusion. Materials and Methods: We reviewed the data of 101 patients with acute basilar artery occlusion receiving endovascular treatment from January 2013 to September 2019. Baseline characteristics and outcomes were evaluated. A favourable functional outcome was defined as a mRS of 0 to 2 assessed at the 3 month follow-up. The association of clinical and procedural characteristics with the functional outcome and mortality was assessed. Results: The study population consisted of 101 patients: 83 males and 18 females. Successful recanalization was achieved in 99 patients (97.1%). A favourable clinical outcome was observed in 50 patients (49.5%), and the overall mortality rate was 26.7%. A favourable outcome was significantly associated with NIHSS score at admission and lung infection. Mortality was associated with NIHSS score at admission, the number of thrombectomy device passes, the postoperative pons-midbrain index, and diabetes mellitus. Conclusions: This study suggested that NIHSS score at admission, the number of thrombectomy device passes, the postoperative pons-midbrain index, diabetes mellitus, and lung infection can predict the functional outcome and mortality. These initial results add evidence about the efficacy and safety of endovascular treatment for acute basilar artery occlusion and need to be confirmed by further prospective studies.

Novel Diffusion-Weighted Imaging Score Showed Good Prognostic Value for Acute Basilar Artery Occlusion Following Endovascular Treatment: The Pons-Midbrain and Thalamus Score

BACKGROUND AND PURPOSE

Prognostic factors for outcome of endovascular treatment remains to be investigated in patients with acute basilar artery occlusion. We aimed to assess the prognostic value of a novel pretreatment diffusion-weighted imaging score: The Pons-Midbrain and Thalamus (PMT) score.

METHODS

Eligible patients who underwent endovascular treatment due to acute basilar artery occlusion were reviewed. The PMT score was a diffusion-weighted imaging-based semiquantitative scale in which the infarctions of pons, midbrain, and thalamus were fully considered. The PMT score was assessed as well as the posterior circulation Acute Stroke Prognosis Early Computed Tomography Score and Brain Stem Score. Good outcomes were defined as a modified Rankin Scale score of ≤3 at 90-day and successful reperfusion as Thrombolysis in Cerebral Infarction grades 2b/3. The associations between baseline clinical parameters and good outcomes were evaluated with logistic regression.

RESULTS

A total of 107 patients with pretreatment magnetic resonance imaging were included in this cohort. The baseline PMT score (median [interquartile range], 3 [1-5] versus 7 [5-9]; P<0.001) and Brain Stem Score (median [interquartile range], 2 [1-4] versus 3 [2-5]; P=0.001) were significantly lower in good outcome group; the posterior circulation Acute Stroke Prognosis Early Computed Tomography Score was higher in good outcome group without statistical significance. As a result of receiver operating characteristic curve analyses, the posterior circulation Acute Stroke Prognosis Early Computed Tomography Score showed poor prognostic accuracy for good outcome (area under the curve, 0.60 [95% CI, 0.49-0.71]; P=0.081); The baseline PMT score showed significantly better prognostic accuracy for 90-day good outcome than the Brain Stem Score and National Institutes of Health Stroke Scale (area under the curve, 0.80 versus 0.68 versus 0.78, P=0.003). In addition, favorable PMT score <7 (odds ratio, 22.0 [95% CI, 6.0-80.8], P<0.001), Brain Stem Score <3 (odds ratio, 4.65 [95% CI, 2.05-10.55], P<0.001) and baseline National Institutes of Health Stroke Scale <23 (odds ratio, 8.0 [95% CI, 2.5-25.6], P<0.001) were associated with improved good outcome.

CONCLUSIONS

In patients with acute basilar artery occlusion following endovascular treatment, the pretreatment diffusion-weighted imaging based PMT score showed good prognostic value for clinical outcome.

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

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

Comatose With Basilar Artery Occlusion: Still Odds of Favorable Outcome With Recanalization Therapy

Background: Around 30–60% of patients with basilar artery occlusion (BAO) present with coma, which is often considered as a hallmark of poor prognosis.

Aim: To examine factors that will help predict outcomes in patients with BAO comatose on admission.

Methods: A total of 312 patients with angiography-proven BAO were analyzed. Comas were assessed as Glasgow Coma Scale (GCS) of ≤8 or impaired level of consciousness ascertained in the medical records. Outcomes were evaluated with the modified Rankin Scale (mRS) over a phone call at 3 months. In our study, 53 patients were excluded due to inadequate data on the level of consciousness.

Results: In total, 103/259 (39.8%) of BAO patients were comatose on admission. Factors associated with acute coma were higher age, coronary artery disease, convulsions, extent of early ischemia by posterior circulation Acute Stroke Prognosis Early CT Score (pc-ASPECTS) < 8, absence of patent posterior collateral vasculature, and occlusion over multiple segments of BA. A total of 21/103 (20.4%) of comatose patients had a favorable outcome (mRS 0–3), and 12/103 (11.7%) had a good outcome (mRS 0–2). Factors associated with a favorable outcome in comatose BAO patients were younger age (p = 0.010), less extensive baseline ischemia (p = 0.027), recanalization (p = 0.013), and avoiding symptomatic intracranial hemorrhage (sICH) (p = 0.038). Factors associated with the poorest outcome or death (mRS 5–6) were older age (p = 0.001), diabetes (p = 0.022), atrial fibrillation (p = 0.016), lower median GCS [4 (IQR 3.6) vs. 6 (5–8); p = 0.006], pc-ASPECTS < 8 (p = 0.003), unsuccessful recanalization (p = 0.006), and sICH (p = 0.010). Futile recanalization (mRS 4–6) was significantly more common in comatose patients (49.4 vs. 18.5%, p < 0.001).

Conclusions: One in five BAO patients with acute coma had a favorable outcome. Older patients with cardiovascular comorbidities and already existing ischemic lesions before reperfusion therapies tended to have a poor prognosis, especially if no recanalization is achieved and sICH occurred.

A Pre-Intervention 4-Item Scale for Predicting Poor Outcome Despite Successful Recanalization in Basilar Artery Occlusion

Poor outcome despite successful recanalization is a relatively common occurrence after endovascular therapy (EVT) in acute intracranial large vessel occlusion. We aimed to develop a simple pre-intervention scale with readily available indicators for predicting the 90-day poor outcome in acute basilar artery occlusion (BAO) patients with successful recanalization after EVT. A prospectively registered consecutive cohort of acute BAO patients treated with EVT in a tertiary stroke center during a 6-year period was reviewed. Poor outcome despite successful recanalization was defined as a 90-day mRS of > 3 despite a post-intervention mTICI of ≥ 2b. A logistic regression analysis was employed to develop the predictive scale. The performance of the scale was estimated by ROC curve and Hosmer-Lemeshow test. Poor outcome was observed in 48 of 109 patients included in this study. The proposed scale consisted of four selected pre-intervention predictors, including the NIHSS score, Pons-Midbrain Index (PMI), bilateral thalamic infarction, and Basilar Artery on Computed Tomography Angiography (BATMAN) collateral score. The 4-item scale revealed good discrimination with an area under curve of 0.83 (95% CI = 0.75-0.90) and acceptable calibration assessed by Hosmer-Lemeshow test (P = 0.48). The optimal cutoff value of the scale (range 0-5 points) was ≥ 3 points with 77% sensitivity, 80% specificity, and 79% accuracy. As a pre-intervention predictive model, the 4-item scale has promising predictive value for poor outcome despite successful recanalization in BAO patients treated with EVT. Nevertheless, external validation with blinded outcome is still needed to confirm its performance before clinical application.

Current endovascular strategies for posterior circulation large vessel occlusion stroke: report of the Society of NeuroInterventional Surgery Standards and Guidelines Committee

Background

The aim of this publication is to provide a detailed update on the diagnosis, treatment, and endovascular techniques for posterior circulation emergent large vessel occlusion (pc-ELVO).

Methods

We performed a review of the literature to specifically evaluate this disease and its treatments.

Results

Data were analyzed, and recommendations were reported based on the strength of the published evidence and expert consensus.

Conclusion

While many questions about pc-ELVO remain to be studied, there is evidence to support particular practices in its evaluation and treatment.

Endovascular treatment of acute ischemic stroke in the posterior circulation

Background and purpose Recent randomized clinical trials have proved the efficacy of endovascular treatment of acute ischemic stroke in the anterior circulation. However, the benefit of endovascular treatment of ischemic stroke in the posterior circulation remains to be proven since it was excluded from these trials. We evaluate the benefit of endovascular treatment in posterior circulation strokes. Methods A total of 110 consecutive patients with posterior circulation stroke who underwent endovascular treatment in our institute in the period 1991-2015 were included. Recanalization rate according to modified Treatment in Cerebral Ischemia score and neurological outcome at three months according to modified Rankin Scale were the main outcomes. Collateral circulation, procedural complications and radiological outcome were evaluated in the radiological examinations. Results The median National Institutes of Health Stroke Scale was 31 (IQR: 13-31) and median time from symptom onset to groin puncture was 300 (IQR: 175-463) minutes. Successful recanalization was seen in 80 of 110 patients (73%). Favorable outcome (modified Rankin Scale ≤2) was seen in 38 patients (35%) while moderate favorable outcome (≤3) was seen in 48 patients (44%). Symptomatic intracerebral hemorrhage occurred in 10 patients (9%). An association between collateral circulation, recanalization rate and outcome was seen. Conclusion Endovascular treatment for posterior circulation stroke in this single-center cohort is relatively safe and effective with decreased mortality and increased favorable outcome compared to natural history.

Neuroimaging Predictors of Clinical Outcome in Acute Basilar Artery Occlusion

Certain early neuroimaging findings are independent predictors of clinical outcome in acute basilar artery occlusion. These imaging findings may serve as important baseline imaging characteristics as well as subgroups in future randomized controlled trials. The purpose of this review is to review and compare early neuroimaging findings seen on non-invasive cranial imaging that predict clinical outcome in acute basilar artery occlusion.