Stroke mechanisms and outcomes of isolated symptomatic basilar artery stenosis

Percutaneous transluminal angioplasty and stenting (PTAS) in patients with symptomatic intracranial vertebrobasilar artery stenosis (IVBS)

BACKGROUND

Approximately 20% of all transient ischaemic attacks (TIAs) and ischaemic strokes occur within the posterior circulation, with vertebrobasilar stenosis identified as the cause in roughly 25% of the cases. Studies have shown that about a quarter of these patients have atherosclerotic stenosis of at least 50% of the vertebrobasilar artery. Stenosis has been shown to be associated with an increased risk of 90-day recurrent vertebrobasilar stroke, particularly in the first few weeks, which is significantly higher when compared with patients with stenosis of the anterior circulation. Therefore, aggressive treatment is important for the patient's prognosis. Stenting is emerging as a promising therapeutic strategy for persistent ischaemia events that do not respond to the best medical treatment, but it is not without complications. We systematically reviewed the literature on percutaneous transluminal angioplasty and stenting (PTAS) for intracranial vertebrobasilar artery stenosis (IVBS).

METHODS

PubMed, Web-of-Science and Scopus were searched upon the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to include prospective/retrospective cohort, randomised/non-randomised clinical trials and case series studies describing PTAS for IVBS. Pooled rates of intervention-related complications and outcomes were analysed with random-effect model meta-analysis using StataMP V.18.0 software.

RESULTS

31 studies were found eligible which included 1928 cases. 1103 basilar artery stenosis cases were reported in 27 studies 0.65 (95% CI 0.53, 0.76), I2: 99.72%. 648 vertebral cases were reported in 18 studies 0.60 (95% CI 0.49, 0.70), I2: 97.49%. In four studies, the rate of vertebrobasilar stenosis cases calculated as a proportion of the total sample size was 0.10 (95% CI 0.05, 0. 15). Mean stenosis in 21 included studies was found to be 0.83 (95% CI 0.79, 0.88), I2: 0.00%, which shows variation of baseline stenosis between studies was minimal. 51 deaths were recorded in 24 studies. Meta-analysis of mortality showed the overall rate of mortality was 0.03 (95% CI 0.02, 0.05), I2: 44.90%. In 14 studies, symptomatic intracranial haemorrhage events were recorded at an overall rate of 0.01 (95% CI 0.00, 0.02), I2: 0.00%. Generally, a follow-up period of at least 3 months was reported in the included studies. Furthermore, procedural stroke/TIA was evaluated in seven studies, four of which reported no events (0.03 (95% CI 0.00, 0.08), I2: 20.38%). Mean time from initial symptoms to recanalisation was 23.98 (95% CI 18.56, 29.40), I2=98.8%, p=0.00 days.

CONCLUSION

In certain individuals with medically unresolved, severe, symptomatic and non-acute IVBS, elective vertebrobasilar PTAS appears to be both safe and effective. Various stent designs and angioplasty-assisted techniques should be taken into consideration based on the specific clinical and radiological traits of the lesions. Future randomised controlled trials are required to verify these results.

Unmasking the Basilar Culprit: A Case of Acute Posterior Circulation Stroke in a Diabetic Septuagenarian

A 76-year-old man with poorly controlled diabetes mellitus, with an HbA1c of 10.9% (4.7%-6.4%), presents with acute right facial numbness, transient right eye foggy vision, and near syncope. Neuroimaging revealed substantial basilar artery stenosis with acute infarction in the region of the right posterior cerebral artery, impacting the medial temporal, occipital, thalamus, and midbrain. Although basilar artery stenosis is uncommon, its combination with poorly managed diabetes and posterior circulation involvement makes therapy difficult. Partial neurological recovery was observed with dual antiplatelet treatment and intensive risk factor management. Basilar artery stenosis has a poor prognosis; however, early detection, medical therapy, and comorbidity control can improve patient outcomes and reduce recurrence risk. The example further emphasizes the necessity of preventative treatment in high-risk patients and the link between diabetes control and posterior circulation stroke risk.

Comprehensive imaging analysis of intracranial atherosclerosis

Intracranial atherosclerotic disease (ICAD) involves the build-up of atherosclerotic plaques in cerebral arteries, significantly contributing to stroke worldwide. Diagnosing ICAD entails various techniques that measure arterial stenosis severity. Digital subtraction angiography, CT angiography, and magnetic resonance angiography are established methods for assessing stenosis. High-resolution MRI offers additional insights into plaque morphology including plaque burden, hemorrhage, remodeling, and contrast enhancement. These metrics and plaque traits help identify symptomatic plaques. Techniques like transcranial Doppler, CT perfusion, computational fluid dynamics, and quantitative MRA analyze blood flow restrictions due to ICAD. Intravascular ultrasound or optical coherence tomography have a very high spatial resolution and can assess the structure of the arterial wall and the plaque from the lumen of the target vascular territory. Positron emission tomography could further detect inflammation markers. This review aims to provide a comprehensive overview of the spectrum of current modalities for atherosclerotic plaque analysis and risk stratification.

Tmax >4 s volume predicts stroke recurrence in symptomatic intracranial atherosclerotic stenosis with optimal medical treatment

BACKGROUND

The time to maximum (Tmax) profile based on computed tomography perfusion (CTP) provides a quantitative assessment of cerebral hemodynamic compromise. We aimed to delineate the Tmax profile in stroke patients with symptomatic intracranial atherosclerotic stenosis (ICAS) and to investigate its predictive role in stroke recurrence after optimal medical treatment.

METHODS

Consecutive patients with ischemic stroke within 30 days attributed to 50%-99% ICAS were prospectively enrolled. Baseline tissue volume at different perfusion parameter thresholds based on CTP was automatically calculated using the Rapid Processing of Perfusion and Diffusion (RAPID) software. All patients received optimal medical treatment. The primary outcome was a composite of stroke in the territory of qualifying artery or vascular death within 1 year.

RESULTS

Among 204 patients with symptomatic ICAS, the median volume of Tmax >4 s, Tmax >6 s, and relative cerebral blood flow (rCBF) <30% were 61 mL, 0 mL, and 0 mL, respectively. The 1 year rate of primary outcome was 16.2% (33/204). Tmax >4 s volume was significantly associated with the primary outcome (per 10 mL increase, adjusted hazard ratio (HR), 1.028 (1.008-1.049), P=0.005). The optimal cut-off value of Tmax >4 s volume for predicting the primary outcome was 83 mL. Patients with Tmax >4 s volume >83 mL had a higher risk of the 1 year primary outcome than those with Tmax >4 s volume ≤83 mL (adjusted HR, 7.346 (3.012-17.871), P<0.001), after adjusting for degree of stenosis and stroke mechanisms.

CONCLUSION

Tmax >4 s volume is a promising perfusion parameter to define hemodynamic compromise in patients with symptomatic ICAS. Patients with a larger volume of Tmax >4 s are likely to have a higher risk of stroke recurrence despite optimal medical treatment.

Evaluation of the effect on stroke mechanism, stroke recurrence and clinical outcome in stroke patients with basilar artery atherosclerosis: A single centre retrospective observational study

OBJECTIVES

Basilar artery atherosclerotic plaque is the predominant cause of stroke in the posterior circulation. İscheamic stroke caused basilar artery atherosclerosis faces a high risk of recurrence despite optimal medical treatment, which might lie in the less than ideal recognition of underlying stroke mechanism and lack of individualized treatment for strokes of different mechanisms. We aim in this study to investigate the effect on stroke mechanism, stroke recurrence and clinical outcome in stroke patients with basilar artery atherosclerosis.

METHODS

In this study, 107 ischaemic stroke patients with atherosclerotic stenosis in the BA who were followed up in Uludag University Faculty of Medicine between 1 January 2019 and 1 January 2022. The study was conducted retrospectively and observationally.

RESULTS

According to the results of our study, the degree of stenosis in atherosclerotic stenosis of the symptomatic basilar artery was found to be an independent risk factor for stroke recurrence. Independent risk factors for unfavourable clinical outcomes in these patients were determined as female gender, stenosis being in the proximal segment, stroke mechanism being from artery to artery embolism, and congestive heart failure.

CONCLUSION

The most striking result of our study is that clinical outcome was found to be closely related to the female gender, the stroke mechanism being artery-to-artery embolism, and the stenosis is in the proximal segment. If stroke mechanisms were evaluated more clearly, it would likely help provide individualised treatments.

Prospective study on ultrasound-guided stellate ganglion block improves cerebral blood flow in patients with stroke

OBJECTIVES

The effect of routine internal medicine and stroke rehabilitation treatment was not good. To confirm that ultrasound-guided stellate ganglion block (SGB) can improve cerebral blood flow in patients with stroke, Transcranial Doppler (TCD) and carotid ultrasound were used to monitor the cerebral blood flow parameters of ultrasound-guided SGB in patients with stroke.

METHODS

A prospective study of 40 patients with stroke from January 2021 to October 2022 randomly divided into two groups (group SGB: undergoing ultrasound-guided SGB and standard medical procedures, control group: undergoing standard medical procedures) with 20 cases in each was conducted in People's Hospital of Chongqing Liang Jiang New Area. TCD and carotid artery ultrasound were monitored before and after treatment. There were no significant differences in general data on age, gender, disease course, and stroke type between two groups (P>0.05).

RESULTS

After treatment, the bilateral ACA Vm of group SGB was significantly higher, the bilateral internal carotid artery RI and left VA RI were significantly lower than in control group (P<0.05). In group SGB, the Vm of bilateral MCA, bilateral PCA, right ACA, bilateral VA, and BA after treatment were significantly (P<0.05) increased compared to before treatment. PI of bilateral MCA, right ACA, and left VA after treatment were significantly (P<0.05) decreased compared to before treatment. RI of bilateral MCA, bilateral PCA, and bilateral VA after treatment were significantly (P<0.05) decreased compared to before treatment. Right internal carotid artery D after treatment was significantly (P<0.05) higher than before treatment. RI of bilateral internal carotid artery after treatment was significantly (P<0.05) lower than before treatment.

CONCLUSIONS

Ultrasound-guided stellate ganglion block could improve local cerebral blood flow and vascular compliance in patients with stroke, and reduce vascular resistance.

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.

Endovascular Treatment of Symptomatic Basilar Artery Stenosis

PURPOSE

While symptomatic basilar artery (BA) stenosis is associated with a higher risk of recurrent stroke or death, there is no consensus on the management of these patients who are refractory to antiplatelet therapy. This study retrospectively assesses the outcomes of endovascular treatment (EVT) for symptomatic BA stenosis.

MATERIALS AND METHODS

We conducted a retrospective review of patients with symptomatic BA stenosis who underwent EVT, including angioplasty or stenting, from 2006 to 2018. A total of 15 patients, who experienced transient ischemic attacks or strokes despite dual antiplatelet therapy, were included. EVT was performed under local anesthesia after pretreatment with antiplatelet medications. Angiographic follow-up was performed at 12 and 24 months post-EVT. Clinical outcomes were evaluated using the modified Rankin Scale (mRS).

RESULTS

EVT was successfully completed in all patients. Peri/post-procedural complications occurred in 33% of cases, including in-stent thrombosis, intracranial hemorrhage, and pontine infarction. At long-term follow-up (mean 98.5±80.5 months), 73.3% of patients achieved a favorable functional outcome (mRS≤2) without disability or mortality. Patients with unfavorable outcomes had previous infarcts, with 2 experiencing new pontine infarctions after stenting.

CONCLUSION

This study suggests that EVT, including angioplasty and stenting, may offer promise as a treatment option for symptomatic BA stenosis refractory to medical therapy. However, the procedure carries a notable risk of complications, especially in patients with severe stenosis and previous infarcts. Careful patient selection, based on clinical and radiological criteria, is crucial.

Percutaneous transluminal angioplasty and/or stenting for the treatment of basilar artery stenosis: a systematic review and meta-analysis

PURPOSE

Basilar artery stenosis (BAS) carries high morbidity and mortality, with variable outcomes after endovascular treatments. We systematically reviewed the literature on percutaneous transluminal angioplasty and/or stenting (PTAS) for BAS.

METHODS

PubMed, EMBASE, Web-of-Science, Scopus, and Cochrane were searched upon the PRISMA guidelines to include prospective/retrospective cohort studies describing PTAS for BAS. Pooled rates of intervention-related complications and outcomes were analyzed with random-effect model meta-analyses.

RESULTS

We included 25 retrospective cohort studies comprising 1016 patients. All patients were symptomatic, presenting with transient ischemic attack or ischemic stroke. BAS frequently involved the middle basilar artery (51.4%), mostly classified as Mori-B (57.4%). PTAS for BAS was indicated in severe (≥ 50-70%), symptomatic BAS refractory to dual antiplatelet therapy. Patients underwent angioplasty (95.5%) and/or stenting (92.2%), preferably using Wingspan or Apollo stents. Median baseline BAS was 81% (range, 53-99%), while median post-intervention BAS was 13% (0-75%). Actuarial rates of successful intervention and "good" final outcome were 100% (95% CI: 100-100%) and 89% (95% CI: 85-93%). Intervention-related recurrent ischemic stroke occurred in 85 patients (8.3%) with actuarial rates of 5% (95% CI: 4-7%), differentiated into perforator (5.4%), in-stent (2.6%), and embolic (0.4%). Actuarial rates of intervention-related dissection, restenosis, and death were 0% (95% CI: 0-0%), 1% (95% CI: 0-1%), and 0% (95% CI: 0-2%).

CONCLUSION

Elective PTAS appears to be safe and effective in selected patients with medically refractory, severe, symptomatic, and non-acute BAS. Different stent types and angioplasty-assisted procedures should be considered based on specific clinico-radiological characteristics of the lesions. Future randomized controlled trials are required to corroborate these findings.

Clinical value of microemboli combined with cerebrospinal fluid inflammatory factor level monitoring in predicting recurrent stroke of middle cerebral artery stenosis

OBJECTIVE

To evaluate the clinical value of microemboli combined with cerebrospinal fluid inflammatory factor level monitoring in the prediction of recurrent stroke in middle cerebral artery stenosis.

METHODS

This is a retrospective study. Patients (n=170) who were hospitalized in the Department of Neurology of the First People's Hospital of Jiangxia District from June 2019 to January 2021 with cerebral infarction or transient ischemic attack were included in the study. Among them, 85 patients with ischemic attack were divided into the non-recurrent stroke group (primary onset, n=40) and the recurrent stroke group (history of cerebral infarction or transient ischemic attack within 5 years prior to the onset, n=45). Routine blood biochemical tests were performed using the Olympus 5800 automated chemical analyzer. Cerebrospinal fluid levels of inflammatory factors (TNF-α, IL-6) were detected by ELISA kits. Special Doppler hyperintensities for microemboli in cerebral blood flow were tested by transcranial Doppler ultrasound.

RESULTS

The mean age, statins and LDL-C were higher in the recurrent stroke group than the non-recurrent stroke group (P<0.05). The levels of cerebrospinal fluid TNF-α, PCT, CRP and IL-6 in the recurrent stroke group were higher than the non-recurrent stroke group (P<0.05). The proportion of grade 0 microemboli in the recurrent stroke group was lower than the non-recurrent stroke group (P<0.05), and the proportion of grade 1, 2, 3, 4 and 5 microemboli was higher than the non-recurrent stroke group (P<0.05). The positive rate of microemboli in the recurrent stroke group was higher than the non-recurrent stroke group (P<0.05). The accuracy rate of microemboli combined with cerebrospinal fluid inflammatory factor level monitoring in the recurrent stroke group for the prediction of recurrent stroke due to middle cerebral artery stenosis was higher than that in the non-recurrent stroke group (P<0.05). Increased age, statin use, microembolization, and increased LDL-C, TNF-α, PCT, CRP and IL-6 levels were independent risk factors.

CONCLUSION

Microemboli combined with cerebrospinal fluid inflammatory factor level monitoring can increase the detection rate of recurrent stroke in middle cerebral artery stenosis and prevent vascular events to a great extent.

Association of Plaque Morphology With Stroke Mechanism in Patients With Symptomatic Posterior Circulation ICAD

BACKGROUND AND OBJECTIVES

Although the main mechanisms of stroke in patients with intracranial atherosclerotic disease (ICAD)-perforating artery occlusion (PAO) and artery-to-artery embolism (AAE)-have been identified and described, relatively little is known about the morphology of the symptomatic plaques and how they differ between these 2 mechanisms.

METHODS

We prospectively recruited patients with acute ischemic stroke in the posterior circulation that was attributable to ICAD. Fifty-one eligible patients were enrolled and underwent magnetic resonance imaging before being assigned to the PAO or AAE group according to probable stroke mechanism. Plaque morphological properties including plaque length, lumen area, outer wall area, plaque burden, plaque surface irregularity, vessel wall remodeling, and plaque enhancement were assessed using high-resolution MRI. Plaque morphological parameters of both PAO and AAE groups were compared using nonparametric tests. A binary logistic regression model was used to identify independent predictors while a receiver operating characteristic curve tested the sensitivity and specificity of the model.

RESULTS

Among patients who met the imaging eligibility criteria, 38 (74.5%) had PAO and 13 (25.5%) had AAE. Plaque length was shorter (6.39 interquartile range [IQR, 5.18-7.7]1 mm vs 10.90 [IQR, 8.18-11.85] mm, p < 0.01) in patients with PAO. Plaque burden was lower in PAO group (78.00 [IQR, 71.94-86.35] % vs 86.37 [IQR, 82.24-93.04] %, p = 0.04). The proportion of patients with plaque surface irregularity was higher in patients with AAE than in patients with PAO (19/38, 50.00% vs 12/13, 92.30%, p = 0.008). Plaque length was significantly associated with the PAO mechanism (adjusted OR 0.57, 95% CI, 0.41-0.79).

DISCUSSION

Intracranial atherosclerotic plaque morphology differs between patients with PAO and those with AAE. Plaque with shorter length, lower plaque burden, and regular surface is more likely to cause PAO.

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.

3D Enhancement Color Maps in the Characterization of Intracranial Atherosclerotic Plaques

BACKGROUND AND PURPOSE

High-resolution MR imaging allows the identification of culprit symptomatic plaques after the administration of gadolinium. Current high-resolution MR imaging methods are limited by 2D multiplanar views and manual sampling of ROIs. We analyzed a new 3D method to objectively quantify gadolinium plaque enhancement.

MATERIALS AND METHODS

Patients with stroke due to intracranial atherosclerotic disease underwent 7T high-resolution MR imaging. 3D segmentations of the plaque and its parent vessel were generated. Signal intensity probes were automatically extended from the lumen into the plaque and the vessel wall to generate 3D enhancement color maps. Plaque gadolinium (Gd) uptake was quantified from 3D color maps as gadolinium uptake = (µPlaque T1 + Gd -µPlaque T1/SDPlaque T1). Additional metrics of enhancement such as enhancement ratio, variance, and plaque-versus-parent vessel enhancement were also calculated. Conventional 2D measures of enhancement were collected for comparison.

RESULTS

Thirty-six culprit and 44 nonculprit plaques from 36 patients were analyzed. Culprit plaques had higher gadolinium uptake than nonculprit plaques (P < .001). Gadolinium uptake was the most accurate metric for identifying culprit plaques (OR, 3.9; 95% CI 2.1-8.3). Gadolinium uptake was more sensitive (86% versus 70%) and specific (71% versus 68%) in identifying culprit plaques than conventional 2D measurements. A multivariate model, including gadolinium uptake and plaque burden, identified culprit plaques with an 83% sensitivity and 86% specificity.

CONCLUSIONS

The new 3D color map method of plaque-enhancement analysis is more accurate for identifying culprit plaques than conventional 2D methods. This new method generates a new set of metrics that could potentially be used to assess disease progression.

Endovascular treatment for acute basilar artery occlusion due to different stroke etiologies of large artery atherosclerosis and cardioembolism

Introduction

Stroke etiology may affect the prognosis of acute basilar artery occlusion (BAO). This study aimed to estimate the efficacy and safety of endovascular treatment (EVT) in BAO strokes due to the underlying stroke etiologies of large artery atherosclerosis (LAA) and cardioembolism (CE).

Patients and methods

Patients with LAA and CE subtypes from the registry EVT for Acute Basilar Artery Occlusion Study (BASILAR) were selected for this analysis. We estimated the EVT treatment effect relative to standard medical treatment (SMT) in these patients by using a propensity score approach with inverse probability of treatment weighted estimation. Outcomes included 90-day favorable functional outcomes (modified Rankin scale (mRS) 0-3), functional independence (mRS 0-2), all-cause mortality, and symptomatic intracranial hemorrhage (sICH).

Results

A total of 744 patients were included in the final analysis. After weighting with inverse probability of treatment estimation, the patients who, based on their characteristics, were treated with EVT rather than SMT, demonstrated higher rates of favorable functional outcomes in both the LAA (29.2% vs 11.7%, adjusted OR with 95% CI: 4.34 [2.15-8.78], p < 0.001) and the CE subtype (36.0% vs 8.1%, adjusted OR with 95% CI: 9.14 [1.96-42.55], p = 0.005). A similar finding was also observed for functional independence. EVT patients also demonstrated lower rates of mortality than SMT. Among EVT patients, no significant difference was observed in mortality or sICH between LAA and CE groups, but LAA patients had lower rates of favorable functional outcome and functional independence (29.2% vs 37% and 24.2% vs 32.9%, respectively), where the latter remained significant after adjustment for imbalances in baseline data (p = 0.04).

Conclusions

In acute BAO strokes, both LAA and CE patients who, based on their characteristics, were treated with EVT rather than SMT, demonstrated better outcomes. Among EVT patients, LAA and CE subtypes displayed important baseline and treatment differences, and LAA patients were less likely to achieve functional independence at 3 months, but mortality and sICH were similar between LAA or CE subtypes. These results need to be confirmed in future clinical trials.

Endovascular thrombectomy versus standard medical treatment for stroke patients with acute basilar artery occlusion: a systematic review and meta-analysis

BACKGROUND

Whether endovascular thrombectomy (EVT) is superior to standard medical treatment (SMT) for stroke patients with acute basilar artery occlusion (BAO) is uncertain. This systematic review and meta-analysis aimed to compare the safety and efficacy of EVT with SMT for treating BAO patients.

METHODS

Papers were retrieved from PubMed, Embase, and the Cochrane Library databases. The primary outcome of this meta-analysis was favorable functional outcomes at 3 months (defined as a modified Rankin Scale (mRS) score of ≤3). A random effect model was used to calculate risk ratios (RR) with 95% confidence intervals (CIs) per outcome.

RESULTS

Five articles, including two randomized controlled trials (RCTs) and four observational cohort studies, comprising 1484 patients (1024 in the EVT group and 460 in the SMT group), were included in the meta-analysis. The pooled results demonstrated no significant differences between the EVT and SMT groups in achieving favorable functional outcomes at 3 months (RR=1.63, 95% CI 0.90, 2.96; p=0.11). However, patients in the EVT group had higher rates for symptomatic intracerebral hemorrhage (RR=6.22, 95% CI 2.06 to 18.76; p=0.001) but lower mortality at 3 months (RR=0.72, 95% CI 0.56 to 0.91; p=0.007) than patients in the SMT group.

CONCLUSION

Among patients with BAO, EVT and SMT did not differ significantly in achieving favorable functional outcomes at 3 months, but BAO patients treated with EVT might have lower mortality at 3 months. RCTs are warranted to further assess the efficacy and safety of EVT for BAO patients.

Glycoprotein IIb/IIIa inhibitors for the neurointerventionalist

Antiplatelet therapies are commonly used in neurointerventional procedures. However, specific guidelines for their use in these settings is lacking and it can often be difficult to balance the potential risks and benefits of these medications. Considering the continued growth and adoption of neurointerventional procedures, it is crucial to understand the properties of these agents in order to use them safely. Large-scale clinical trials are still needed to clarify many of these aspects for this emerging field. However, the existing literature already provides insight into which antiplatelet drugs are of benefit to the neurointerventionalist as well as their associated risks of ischemic and hemorrhagic complications. Hence, this review focuses on the applications of GPIIb/IIIA inhibitors to neurointerventional procedures.

Posterior Circulation Ischaemic Stroke

Posterior circulation ischaemic stroke (PCIS) is a disease of high burden. They account for 20-25% of all ischaemic strokes. However, it is relatively under-researched and requires more clinical attention, since it carries worse functional outcomes. Vertigo, visual disturbances and sensory/motor disturbances are found in PCIS. Large artery atherosclerosis and embolism are main causes of PCIS, while there is growing evidence that vertebrobasilar dolichoectasia is a key association. Hypertension is the commonest risk factor, while diabetes mellitus is more specific to PCIS. PCIS is diagnosed through neuroimaging techniques, which examine structural brain abnormalities, vascular patency and perfusion. PCIS, in line with ischaemic stroke in general, requires medical treatment and lifestyle modifications. This includes smoking cessation, weight control, and dietary alterations. Aspirin use also significantly improves survival outcomes. While intravascular and intra-arterial thrombolysis improve clinical outcomes, this is not proven conclusively for stenting and angioplasty. Future research on PCIS can focus on multi-centre epidemiological studies, clinically significant anatomical variants, and collateralisation.

Vertebrobasilar Junction Angle Over 90°: A Potential Imaging Marker Associated With Vertebrobasilar Atherosclerosis

Objective: Whether the cerebral vascular variations play an important role in the progression of intracranial atherosclerosis is yet largely unclear. We aimed to investigate the relationship between the magnitude of the vertebrobasilar junction (VBJ) angle and the imaging features of vertebrobasilar artery atherosclerosis.

Methods: Adult patients with acute ischemic stroke or transient ischemic attack undergoing a 3.0-tesla vessel wall magnetic resonance imaging (VW-MRI) scanning were consecutively included. Imaging features of vertebrobasilar artery atherosclerosis were assessed on the reconstructed short axis of VW-MRI at the most stenotic site. The VBJ angle degree was measured on magnetic resonance angiography and classified into the angle ≥90° or <90°.

Results: Among 68 patients (mean age = 63.5 ± 9.4 years old; 63.2% were male) with vertebrobasilar atherosclerosis, 33 had a VBJ angle ≥90° and 35 had a VBJ angle <90°. Compared to the vertebrobasilar plaques with VBJ angle <90°, those with VBJ angle ≥90° had a heavier plaque burden (84.35 vs. 70.58%, p < 0.001) and higher prevalence of intraplaque hemorrhage (17.1 vs. 3.3%, p = 0.01). In the regression analyses, the VBJ angle ≥90° was also robustly associated with plaque burden (odds ratio, 1.11; 95% confidential interval, 1.043–1.18; p = 0.001) and intraplaque hemorrhage (odds ratio, 5.776; 95% confidential interval, 1.095–30.46; p = 0.039) of vertebrobasilar atherosclerosis.

Conclusion: The VBJ angle over 90° might aggravate the vessel wall condition of the atherosclerotic vertebrobasilar arteries, which might serve as a potential risk factor for vertebrobasilar atherosclerosis.

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.

A Whole-Scope Evaluation of Cervicocephalic Atherosclerotic Burden is Essential to Predict 90-Day Functional Outcome in LargeArtery Atherosclerotic Stroke

AIM

Cervicocephalic atherosclerosis (AS) of patients with large-artery atherosclerotic (LAA) stroke might be more closely correlated to the functional outcome than patients with stroke of other etiologies. We aimed to investigate whether a whole-scope evaluation of cervicocephalic AS condition was better at predicting the 90-day functional outcome of LAA stroke than evaluation of intracranial or cervical AS condition alone.

METHODS

Patients with LAA stroke were consecutively enrolled in this study. Computed tomography angiography was performed to evaluate AS condition of various cervicocephalic arterial segments. AS conditions ranging from no AS plaque to complete arterial occlusion scored 0-4 points. Intracranial atherosclerotic burden (IAB) and cervical atherosclerotic burden (CAB) were in respective the sums of AS scores of all intracranial arterial segments and all cervical arterial segments. And the sum of them was intracranial and cervical atherosclerotic burden (ICAB). Relationships of these three scores with the 90-day unfavorable functional outcome (modified Rankin Scale[mRS] score ＞2 points) were compared.

RESULTS

Of 172 patients who finished 90-day follow-up, only ICAB (adjusted odds ratio[OR]=1.10, 95% confidence interval[CI]:1.00-1.21, p=0.044) predicted 90-day unfavorable functional outcome independently of clinical factors, National Institutes of Health Stroke Scale (NIHSS) and mRS scores at admission. ICAB (adjusted hazard ratio[HR]=1.16, 95%CI:1.02-1.32, p=0.029) was related to 90-day recurrent ischemic stroke/death independently of clinical factors and was independently, positively correlated with NIHSS score at admission (r=0.16, p=0.047), whereas IAB and CAB were not.

CONCLUSION

A whole-scope evaluation of cervicocephalic AS condition using ICAB outperformed evaluation of intracranial or cervical AS condition alone in predicting 90-day functional outcome of patients with LAA stroke.

Rescue Endovascular Treatment for Emergent Large Vessel Occlusion With Underlying Intracranial Atherosclerosis: Current State and Future Directions

Intracranial atherosclerosis (ICAS) is one of the most common causes of stroke worldwide and is associated with high risk of stroke recurrence. While the most common clinical presentation is acute–subacute transient ischemic attack or ischemic stroke, occasionally, patients with underlying ICAS present with acute occlusion of the affected vessel. Diagnosis and endovascular management of ICAS-related emergent large vessel occlusion (ELVO) can be challenging. Herein, we review the current evidence supporting endovascular management of ICAS-related ELVO and discuss future directions.

Transradial approach using a distal access catheter without guiding support for symptomatic intracranial vertebral artery and basilar artery stenosis: a multicenter experience and technical procedure

BACKGROUND

There is little consensus on endovascular treatment for symptomatic intracranial posterior circulation stenosis via the transradial approach (TRA). We report our multicenter experience and technical procedures that directly used a distal access catheter (DAC) via TRA for the treatment of symptomatic intracranial vertebral (VA) and basilar (BA) artery stenosis.

METHODS

From January 2019 to December 2020, 92 consecutive patients with severe symptomatic intracranial VA or BA stenosis were retrospectively collected and divided into two groups (TRA group and transfemoral approach (TFA) group) for neurointerventional treatment. The percentages of catheters reaching the V3/V4 segment of the VA and technical success, postoperative care conditions, preoperative outcomes and complications, long term clinical outcomes, and imaging follow-ups were observed.

RESULTS

The catheter, CAT 5, reached the V4 segment of the VA in 37 TRA patients (88.1%). The duration of the procedure was significantly shorter in the TRA group than in the TFA group (median 48.0 min vs 55.5 min, p=0.037). More patients in the TRA group could walk within 2 hours after the procedure (85.7% vs 10.0%, p=0.000), and the duration of retaining catheterization in the TRA group was shorter (3.0±1.2 hours vs 11.7±5.6 hours, p=0.000).

CONCLUSION

This study demonstrates the potential feasibility and safety of using a DAC via the TRA without guiding support for the treatment of symptomatic intracranial VA and BA stenosis. The TRA demonstrated some advantages over the standard TFA in terms of patient comfort. Further randomized controlled trials comparing the TRA and TFA for posterior circulation stenosis are needed.

Risk Factors of New Cerebral Infarctions After Endovascular Treatment for Basilar Artery Stenosis Based on High-Resolution Magnetic Resonance Imaging

Objective: The current study aims to analyze the risk factors of new cerebral infarctions in the distribution of basilar artery (BA) detected by diffusion-weighted imaging (DWI) after endovascular treatment in patients with severe BA stenosis. Methods: Data was collected from the electronic medical records of patients with severely atherosclerotic basilar artery stenosis (≥70%) who underwent endovascular treatment. The plaque characteristics, including the plaque distribution, plaque burden, plaque enhancement index, remodeling ratio, and stenosis degree, were evaluated qualitatively and quantitatively using high-resolution magnetic resonance imaging (HR-MRI) and digital subtraction angiography (DSA). The characteristics of the procedure, such as the type of treatment, balloon diameter, balloon length, stent diameter, and stent length, were analyzed. Results: A total of 107 patients with severe basilar artery stenosis (≥70%) who underwent endovascular treatment were enrolled. The study participants included 77 men and 30 women, with an average age of 61.6 ± 8.1 years. The rate of postoperative new cerebral infarctions was 55.1% (59/107), of which 74.6% (44/59) were caused by artery-to-artery embolism, 6.8% (4/59) due to perforator occlusion, and 18.6% (11/59) were caused by a mixed mechanism. Twelve of 59 patients had ischemic events, with nine cases of stroke and three cases of transient ischemic attacks (TIA). The plaque burden in the DWI-positive group was significantly larger than that in the DWI-negative group (3.7% vs. -8.5%, p = 0.016). Positive remodeling was more common in the DWI-positive group than in the DWI-negative group (35.6% vs. 16.7%, p = 0.028). Smoking was inversely correlated with the rate of new cerebral infarctions (odds ratio, 0.394; 95% confidence interval, 0.167-0.926; p = 0.033). Conclusion: The plaque characteristics are not associated with new cerebral infarctions in the distribution of BA, although a large plaque burden and positive remodeling are more likely to appear in patients with new cerebral infarctions after BA stenting, which warrants further studies with a larger sample size. As for smoking, the inverse correlation with new cerebral infarctions in the BA territory needs large-scale prospective randomized controlled trials to verify.

Detection and Quantification of Symptomatic Atherosclerotic Plaques With High-Resolution Imaging in Cryptogenic Stroke

BACKGROUND AND PURPOSE

High-resolution vessel wall imaging (HR-VWI) is a powerful tool in diagnosing intracranial vasculopathies not detected on routine imaging. We hypothesized that 7T HR-VWI may detect the presence of atherosclerotic plaques in patients with intracranial atherosclerosis disease initially misdiagnosed as cryptogenic strokes.

METHODS

Patients diagnosed as cryptogenic stroke but suspected of having an intracranial arteriopathy by routine imaging were prospectively imaged with HR-VWI. If intracranial atherosclerotic plaques were identified, they were classified as culprit or nonculprit based on the likelihood of causing the index stroke. Plaque characteristics, such as contrast enhancement, degree of stenosis, and morphology, were analyzed. Contrast enhancement was determined objectively after normalization with the pituitary stalk. A cutoff value for plaque-to-pituitary stalk contrast enhancement ratio (CR) was determined for optimal prediction of the presence of a culprit plaque. A revised stroke cause was adjudicated based on clinical and HR-VWI findings.

RESULTS

A total of 344 cryptogenic strokes were analyzed, and 38 eligible patients were imaged with 7T HR-VWI. Intracranial atherosclerosis disease was adjudicated as the final stroke cause in 25 patients. A total of 153 intracranial plaques in 374 arterial segments were identified. Culprit plaques (n=36) had higher CR and had concentric morphology when compared with nonculprit plaques (P≤0.001). CR ≥53 had 78% sensitivity for detecting culprit plaques and a 90% negative predictive value. CR ≥53 (P=0.008), stenosis ≥50% (P<0.001), and concentric morphology (P=0.030) were independent predictors of culprit plaques.

CONCLUSIONS

7T HR-VWI allows identification of underlying intracranial atherosclerosis disease in a subset of stroke patients with suspected underlying vasculopathy but otherwise classified as cryptogenic. Plaque analysis in this population demonstrated that culprit plaques had more contrast enhancement (CR ≥53), caused a higher degree of stenosis, and had a concentric morphology.