Comparison of rescue intracranial stenting versus best medical treatment alone in acute refractory large vessel occlusion: study protocol for the PISTAR multicenter randomized trial.

BACKGROUND: Mechanical thrombectomy (MT) has become a standard treatment for acute ischemic strokes (AIS). However, MT failure occurs in approximately 10-30% of cases, leading to severe repercussions (with mortality rates up to 40% according to observational data). Among the available rescue techniques, rescue intracranial stenting (RIS) appears as a promising option. OBJECTIVE: This trial is poised to demonstrate the superiority of RIS in addition to the best medical treatment (BMT) in comparison with BMT alone, in improving the functional outcomes at 3 months for patients experiencing an AIS due to a large vessel occlusion refractory to MT (rLVO). METHODS: Permanent Intracranial STenting for Acute Refractory large vessel occlusions (PISTAR) is a multicenter prospective randomized open, blinded endpoint trial conducted across 11 French University hospitals. Adult patients (≥18 years) with an acute intracranial occlusion refractory to standard MT techniques will be randomized 1:1 during the procedure to receive either RIS+BMT (intervention arm) or BMT alone (control arm). RESULTS: The primary outcome is the rate of good clinical outcome at 3 months defined as a modified Rankin Scale score ≤2 and evaluated by an independent assessor blinded to the randomization arm. Secondary outcomes include hemorrhagic complications, all adverse events, and death. The number of patients to be included is 346. Two interim analyses are planned with predefined stopping rules. CONCLUSION: The PISTAR trial is the first randomized controlled trial focusing on the benefit of RIS in rLVOs. If positive, this study will open new insights into the management of AIS. TRIAL REGISTRATION NUMBER: NCT06071091.

Cerebral microbleeds and risk of symptomatic hemorrhagic transformation following mechanical thrombectomy for large vessel ischemic stroke.

BACKGROUND AND PURPOSE: In patients with acute ischemic stroke (AIS) treated with endovascular therapy (EVT), the association of pre-existing cerebral small vessel disease (cSVD) with symptomatic intracerebral hemorrhage (sICH) remains controversial. We tested the hypothesis that the presence of cerebral microbleeds (CMBs) and their burden would be associated with sICH after EVT of AIS. METHODS: We conducted a retrospective study combining cohorts of patients that underwent EVT between January 1st 2015 and January 1st 2020. CMB presence, burden, and other cSVD markers were assessed on a pre-treatment MRI, evaluated independently by two observers. Primary outcome was the occurrence of sICH. RESULTS: 445 patients with pretreatment MRI were included, of which 70 (15.7%) demonstrated CMBs on baseline MRI. sICH occurred in 36 (7.6%) of all patients. Univariate analysis did not demonstrate an association between CMB and the occurrence of sICH (7.5% in CMB+ group vs 8.6% in CMB group, p = 0.805). In multivariable models, CMBs' presence was not significantly associated with increased odds for sICH (-aOR- 1.19; 95% CI [0.43-3.27], p = 0.73). Only ASPECTs (aOR 0.71 per point increase; 95% CI [0.60-0.85], p < 0.001) and collaterals status (aOR 0.22 for adequate versus poor collaterals; 95% CI [0.06-0.93], p 0.019) were independently associated with sICH. CONCLUSION: CMB presence and burden is not associated with increased occurrence of sICH after EVT. This result incites not to exclude patients with CMBs from EVT. The risk of sICH after EVT in patients with more than10 CMBs will require further investigation. REGISTRATION: Registration-URL: http://www. CLINICALTRIALS: gov ; Unique identifier: NCT01062698.

Embolization of the middle meningeal artery for the prevention of chronic subdural hematoma recurrence in high-risk patients: a randomized controlled trial-the EMPROTECT study protocol.

BACKGROUND: Middle meningeal artery (MMA) embolization has been proposed as a treatment of chronic subdural hematoma (CSDH). The benefit of the procedure has yet to be demonstrated in a randomized controlled trial. We aim to assess the efficacy of MMA embolization in reducing the risk of CSDH recurrence 6 months after burr-hole surgery compared with standard medical treatment in patients at high risk of postoperative recurrence. METHODS: The EMPROTECT trial is a multicenter open label randomized controlled trial (RCT) involving 12 French centers. Adult patients (≥18 years) operated for CSDH recurrence or for a first episode with a predefined recurrence risk factor are randomized 1:1 to receive either MMA embolization within 7 days of the burr-hole surgery (experimental group) or standard medical care (control group). The number of patients to be included is 342. RESULTS: The primary outcome is the rate of CSDH recurrence at 6 months. Secondary outcomes include the rate of repeated surgery for a homolateral CSDH recurrence during the 6-month follow-up period, the rate of disability and dependency at 1 and 6 months, defined by a modified Rankin Scale (mRS) score ≥4, mortality at 1 and 6 months, total cumulative duration of hospital stay during the 6-month follow-up period, directly or indirectly related to the CSDH and embolization procedure-related complication rates. CONCLUSIONS: The EMPROTECT trial is the first RCT evaluating the benefit of MMA embolization as a surgical adjunct for the prevention of CSDH recurrence. If positive, this trial will have a significant impact on patient care. TRIAL REGISTRATION NUMBER: NCT04372147.

Evaluation of mechanical thrombectomy in acute ischemic stroke related to a distal arterial occlusion: A randomized controlled trial.

RATIONALE: Mechanical thrombectomy (MT) associated with the best medical treatment (BMT) has recently shown efficacy for the management of acute ischemic stroke (AIS) secondary to a large vessel occlusion. However, evidence is lacking regarding the benefit of MT for more distal occlusions. AIM: To evaluate the efficacy in terms of good clinical outcome at 3 months of MT associated with the BMT over the BMT alone in AIS related to a distal occlusion. METHODS: The DISCOUNT trial is a multicenter open-label randomized controlled trial involving French University hospitals. Adult patients (⩾18 years) with an AIS involving the anterior or posterior circulation secondary to a distal vessel occlusion within 6 h of symptom onset or within 24 h if no hyperintense signal on fluid attenuation inversion recovery acquisition will be randomized 1:1 to receive either MT associated with the BMT (experimental group) or BMT alone (control group). The number of patients to be included is 488. STUDY OUTCOMES: The primary outcome is the rate of good clinical outcome at 3 months defined as a modified Rankin scale (mRS) ⩽2 and evaluated by an independent assessor blinded to the intervention arm. Secondary outcomes include recanalization of the occluded vessel within 48 h, angiographic reperfusion in the experimental group, 3-month excellent clinical outcome (mRS ⩽ 1), all adverse events, and death. A cost utility analysis will estimate the incremental cost per quality-adjusted life year (QALY) gained. DISCUSSION: If positive, this study will open new insights in the management of AISs. TRIAL REGISTRATION: ClinicalTrials.gov: NCT05030142 registered on 1 September 2021.

Longitudinal radiological follow-up of individual level non-ischemic cerebral enhancing lesions following endovascular aneurysm treatment.

BACKGROUND: Non-ischemic cerebral enhancing (NICE) lesions following aneurysm endovascular therapy are exceptionally rare, with unknown longitudinal evolution. OBJECTIVE: To evaluate the radiological behavior of individual NICE lesions over time. METHODS: Patients included in a retrospective national multicentric inception cohort were analyzed. NICE lesions were defined, using MRI, as delayed onset punctate, nodular, or annular foci enhancements with peri-lesion edema, distributed in the vascular territory of the aneurysm treatment, with no other confounding disease. Lesion burden and the longitudinal behavior of individual lesions were assessed. RESULTS: Twenty-two patients were included, with a median initial lesion burden of 36 (IQR 17-54) on the first MRI scan. Of the 22 patients with at least one follow-up MRI scan, 16 (73%) had new lesions occurring mainly within the first 200 weeks after the date of the procedure. The median number of new lesions per MRI was 6 (IQR 2-16). Among the same 22 patients, 7 (32%) had recurrent lesions. The median persistent enhancement of a NICE lesion was 13 weeks (IQR 6-30). No factor was predictive of early regression of enhancement activity with lesion regression kinetics mainly being patient-dependent. CONCLUSIONS: The behavior of individual NICE lesions was found to be highly variable with an overall patient-dependent regression velocity.

Diffusion-Weighted Imaging Lesion Reversal in Older Patients With Stroke Treated With Mechanical Thrombectomy.

BACKGROUND: Diffusion-weighted imaging lesion reversal (DWIR) is frequently observed after mechanical thrombectomy for acute ischemic stroke, but little is known about age-related differences and impact on outcome. We aimed to compare, in patients <80 versus ≥80 years old, (1) the effect of successful recanalization on DWIR and (2) the impact of DWIR on functional outcome. METHODS: We retrospectively analyzed data of patients treated for an anterior circulation acute ischemic stroke with large vessel occlusion in 2 French hospitals, who underwent baseline and 24-hour follow-up magnetic resonance imaging, with baseline DWI lesion volume ≥10 cc. The percentage of DWIR (DWIR%), was calculated as follows: DWIR%=(DWIR volume/baseline DWI volume)×100. Data on demographics, medical history, and baseline clinical and radiological characteristics were collected. RESULTS: Among 433 included patients (median age, 68 years), median DWIR% after mechanical thrombectomy was 22% (6-35) in patients ≥80, and 19% (interquartile range, 10-34) in patients <80 (P=0.948). In multivariable analyses, successful recanalization after mechanical thrombectomy was associated with higher median DWIR% in both ≥80 (P=0.004) and <80 (P=0.002) patients. In subgroup analyses performed on a minority of subjects, collateral vessels status score (n=87) and white matter hyperintensity volume (n=131) were not associated with DWIR% (P>0.2). In multivariable analyses, DWIR% was associated with increased rates of favorable 3-month outcomes in both ≥80 (P=0.003) and <80 (P=0.013) patients; the effect of DWIR% on outcome was not influenced by the age group (P interaction=0.185) Conclusions: DWIR might be an important and nonage-dependent effect of arterial recanalization, as it seems to beneficially impact 3-month outcomes of both younger and older subjects treated with mechanical thrombectomy for acute ischemic stroke and large vessel occlusion.

Internal carotid artery patency after mechanical thrombectomy for stroke due to occlusive dissection: Impact on outcome.

Introduction: Internal carotid artery dissection (ICAD) is a rare cause of acute ischemic stroke with large vessel occlusion (AIS-LVO). We aimed investigating the impact on outcome of internal carotid artery (ICA) patency after mechanical thrombectomy (MT) for AIS-LVO due to occlusive ICAD. Patients and methods: We included consecutive patients with AIS-LVO due to occlusive ICAD treated with MT from January 2015 to December 2020 in three European stroke centers. We excluded patients with unsuccessful intracranial reperfusion after MT (modified Thrombolysis in Cerebral Infarction (mTICI) score < 2b). We compared 3-month favorable clinical outcome rate, defined as a modified Rankin scale (mRS) score ⩽2, according to ICA status (patency vs occlusion) at the end of MT and at 24-h follow-up imaging, using univariate and multivariable models. Results: Among 70 included patients, ICA was patent in 54/70 (77%) at the end of MT, and in 36/66 (54.5%) patients with 24-h follow-up imaging. Among patients with ICA patency at the end of MT, 32% presented ICA occlusion at 24-h control imaging. Favorable 3-month outcome occurred in 41/54 (76%) patients with ICA patency post-MT and in 9/16 (56%) patients with occluded ICA post-MT (p = 0.21). Rates of favorable outcome were significantly higher in patients with 24-h ICA patency compared to patients with 24-h ICA occlusion (32/36 [89%] vs 15/30 [50%]), with an adjusted odds ratio of 4.67 (95% CI: 1.26-17.25). Discussion and conclusion: Obtaining sustained (24-h) ICA patency after MT could be a therapeutic target for improving functional outcome in patients with AIS-LVO due to ICAD.

Endovascular Therapy or Medical Management Alone for Isolated Posterior Cerebral Artery Occlusion: A Multicenter Study.

BACKGROUND: Whether endovascular therapy (EVT) added on best medical management (BMM), as compared to BMM alone, is beneficial in acute ischemic stroke with isolated posterior cerebral artery occlusion is unknown. METHODS: We conducted a multicenter international observational study of consecutive stroke patients admitted within 6 hours from symptoms onset in 26 stroke centers with isolated occlusion of the first (P1) or second (P2) segment of the posterior cerebral artery and treated either with BMM+EVT or BMM alone. Propensity score with inverse probability of treatment weighting was used to account for baseline between-groups differences. The primary outcome was 3-month good functional outcome (modified Rankin Scale [mRS] score 0-2 or return to baseline modified Rankin Scale). Secondary outcomes were 3-month excellent recovery (modified Rankin Scale score 0-1), symptomatic intracranial hemorrhage, and early neurological deterioration. RESULTS: Overall, 752 patients were included (167 and 585 patients in the BMM+EVT and BMM alone groups, respectively). Median age was 74 (interquartile range, 63-82) years, 329 (44%) patients were female, median National Institutes of Health Stroke Scale was 6 (interquartile range 4-10), and occlusion site was P1 in 188 (25%) and P2 in 564 (75%) patients. Baseline clinical and radiological data were similar between the 2 groups following propensity score weighting. EVT was associated with a trend towards lower odds of good functional outcome (odds ratio, 0.81 [95% CI, 0.66-1.01]; P=0.06) and was not associated with excellent functional outcome (odds ratio, 1.17 [95% CI, 0.95-1.43]; P=0.15). EVT was associated with a higher risk of symptomatic intracranial hemorrhage (odds ratio, 2.51 [95% CI, 1.35-4.67]; P=0.004) and early neurological deterioration (odds ratio, 2.51 [95% CI, 1.64-3.84]; P<0.0001). CONCLUSIONS: In this observational study of patients with proximal posterior cerebral artery occlusion, EVT was not associated with good or excellent functional outcome as compared to BMM alone. However, EVT was associated with higher rates of symptomatic intracranial hemorrhage and early neurological deterioration. EVT should not be routinely recommended in this population, but randomization into a clinical trial is highly warranted.

Early reocclusion after successful mechanical thrombectomy for large artery occlusion-related stroke.

BACKGROUND AND PURPOSE: Despite initial successful recanalization after mechanical thrombectomy (MT), some patients with large artery occlusion (LAO)-related stroke will experience an early reocclusion of the injured vessel which may worsen their prognosis. We aimed to investigate the prevalence, associated factors and prognosis of early reocclusion after successful MT in a large prospective cohort of stroke patients with LAO. METHODS: We included patients from the Lille reperfusion registry with LAO-related stroke involving M1 segment, internal carotid artery terminus or tandem ICA-M1 occlusion, with successful recanalization after MT and available 24 h imaging follow-up. Early reocclusion was defined as internal carotid artery terminus or M1 occlusion on 24 h magnetic resonance imaging (MRI) or computed tomography (CT) vascular imaging. Multivariable logistic regression models were used to investigate factors associated with early reocclusion and its impact on outcomes. RESULTS: Between 2015 and 2020, 62 of 1015 included patients experienced an early reocclusion (6.1%). Age (odds ratio (OR) per 15 years decrease: 1.38 (1.05-1.81)) antiplatelet use (OR: 0.41 (0.19-0.89)), several device passes (OR: 2.13 (1.18-3.83)), atherosclerosis cause (OR: 2.38 (1.19-4.78)), and early clinical worsening (OR: 2.45 (1.18-5.07)) were independently associated with early reocclusion. Early reocclusion was independently associated with poor prognosis (OR: 7.15 (3.49-14.65)) and mortality (OR: 2.05 (1.07-3.91)) at 3 months. CONCLUSION: Six percent of patients with LAO-related stroke and initial successful recanalization experienced early reocclusion. This event is associated with a 7-fold increased risk of poor functional outcome and a 2-fold increased risk of mortality. Further efforts are warranted to refine early detection of patients at risk of reocclusion and to improve their management.

Antithrombotic therapies for neurointerventional surgery: a 2021 French comprehensive national survey.

BACKGROUND: Neurointerventionists lack guidelines for the use of antithrombotic therapies in their clinical practice; consequently, there is likely to be significant heterogeneity in antithrombotic use between centers. Through a nationwide survey, we aimed to obtain an exhaustive cross-sectional overview of antithrombotic use in neurointerventional procedures in France. METHODS: In April 2021, French neurointerventional surgery centers were invited to participate in a nationwide 51-question survey disseminated through an active trainee-led research collaborative network (the JENI-RC). RESULTS: All 40 centers answered the survey. Fifty-one percent of centers reported using ticagrelor and 43% used clopidogrel as premedication before intracranial stenting. For flow diversion treatment, dual antiplatelet therapy was maintained for 3 or 6 months in 39% and 53% of centers, respectively, and aspirin was prescribed for 12 months or more than 12 months in 63% and 26% of centers, respectively. For unruptured aneurysms, the most common heparin bolus dose was 50 IU/kg (59%), and only 35% of centers monitored heparin activity for dose adjustment. Tirofiban was used in 64% of centers to treat thromboembolic complications. Fifteen percent of these comprehensive stroke centers reported using tenecteplase to treat acute ischemic strokes. Cangrelor appeared as an emergent drug in specific indications. CONCLUSION: This nationwide survey highlights the important heterogeneity in clinical practices across centers. There is a pressing need for trials and guidelines to further evaluate and harmonize antithrombotic regimens in the neurointerventional field.

Perfusion Imaging and Clinical Outcome in Acute Minor Stroke With Large Vessel Occlusion.

BACKGROUND: Whether bridging therapy (intravenous thrombolysis [IVT] followed by mechanical thrombectomy) is superior to IVT alone in minor stroke with large vessel occlusion is unknown. Perfusion imaging may identify subsets of large vessel occlusion-related minor stroke patients with distinct response to bridging therapy. METHODS: We conducted a multicenter international observational study of consecutive IVT-treated patients with minor stroke (National Institutes of Health Stroke Scale score ≤5) who had an anterior circulation large vessel occlusion and perfusion imaging performed before IVT, with a subset undergoing immediate thrombectomy. Propensity score with inverse probability of treatment weighting was used to account for baseline between-groups differences. The primary outcome was 3-month modified Rankin Scale score 0 to 1. We searched for an interaction between treatment group and mismatch volume (critical hypoperfusion-core volume). RESULTS: Overall, 569 patients were included (172 and 397 in the bridging therapy and IVT groups, respectively). After propensity-score weighting, the distribution of baseline variables was similar across the 2 groups. In the entire population, bridging was associated with lower odds of achieving modified Rankin Scale score 0 to 1: odds ratio, 0.73 [95% CI, 0.55-0.96]; P=0.03. However, mismatch volume modified the effect of bridging on clinical outcome (Pinteraction=0.04 for continuous mismatch volume); bridging was associated with worse outcome in patients with, but not in those without, mismatch volume <40 mL (odds ratio, [95% CI] for modified Rankin Scale score 0-1: 0.48 [0.33-0.71] versus 1.14 [0.76-1.71], respectively). Bridging was associated with higher incidence of symptomatic intracranial hemorrhage in the entire population, but this effect was present in the small mismatch subset only (Pinteraction=0.002). CONCLUSIONS: In our population of large vessel occlusion-related minor stroke patients, bridging therapy was associated with lower rates of good outcome as compared with IVT alone. However, mismatch volume was a strong modifier of the effect of bridging therapy over IVT alone, notably with worse outcome with bridging therapy in patients with mismatch volume ≤40 mL. Randomized trials should consider adding perfusion imaging for patient selection.

Unusual Histopathological Findings in Mechanically Removed Stroke Thrombi - A Multicenter Experience.

Background: Several studies have investigated the histopathology of mechanically retrieved thrombi from stroke patients. Thrombi with unusual components constitute about 1-2% of all stroke thrombi in clinical practice. Knowledge about these rare components is limited. Objectives: To characterize the histopathology of unusual stroke thrombi from a real-world setting with relation to clinical presentation, patient characteristics and procedural aspects of mechanical thrombectomy. Methods: One-thousand and eight thrombi retrieved from stroke patients with mechanical thrombectomy at three different hospitals were retrospectively reviewed for unusual histological components. Fifteen thrombi were included in the study for further histopathological analysis. Clinical data and data on procedural aspects were collected. Results: We identified six cases with large amounts of extracellular DNA, of which three were calcified. All six cases except one received anticoagulant therapy. We describe two types of calcifications that differ with respect to general calcification morphology, von Kossa staining pattern, macrophage immunophenotype and presence of multinucleated giant cells. Cholesterol-rich (n = 3), adipocyte-like pattern-rich (n = 2), collagen-rich (n = 2) and myxomatous (n = 1) thrombi were also identified and are discussed with regard to pathogenesis and clinical and intervention characteristics. Finally, a thrombus with parts of a vascular wall is described. Suggestions for future studies are made and clinical and technical aspects of the management for these rare but important patients are discussed. Conclusion: In our retrospective multicenter study, we characterized stroke thrombi histopathologically and found subgroups of thrombi defined by presence of rarely seen components. These defined subgroups showed relation to underlying cardiovascular disease, patient characteristics, and mechanical thrombectomy technique. Knowledge about these components may increase our understanding of stroke pathophysiology and influence interventional procedures.

TAGE Score for Symptomatic Intracranial Hemorrhage Prediction After Successful Endovascular Treatment in Acute Ischemic Stroke.

BACKGROUND: Determine if early venous filling (EVF) after complete successful recanalization with mechanical thrombectomy in acute ischemic stroke is an independent predictor of symptomatic intracranial hemorrhage (sICH) and integrate EVF into a risk score for sICH prediction. METHODS: Consecutive patients with anterior acute ischemic stroke treated by mechanical thrombectomy issued from patients enrolled in the THRACE trial (Thrombectomie des Artères Cérébrales) and from 2 prospective registries were included and divided into a derivation (Center I; n=402) and validation cohorts (THRACE and center 2; n=507). EVF was evaluated by 2 blinded readers. sICH was defined according to the modified European cooperative acute stroke study II. Clinical and radiological data were analyzed in the derivation cohort (C1) to identify independent predictors of sICH and construct a predictive score test on the validation cohort (THRACE + C2). RESULTS: Symptomatic ICH rate was similar between the two cohorts (9.9% and 8.9% respectively, P=0.9). Time from onset-to-successful recanalization >270 minutes (odds ratio [OR], 7.8 [95% CI, 2.5-24]), Alberta Stroke Program Early CT Score (≤5 [OR, 2.49 (95% CI, 1.8-8.1) or 6-7 [OR, 1.15 (95% CI, 1.03-4.46)]), glucose blood level >7 mmol/L (OR, 2.92 [95% CI, 1.26-6.7]), and EVF presence (OR, 11.9 [95% CI, 3.8-37.5]) were independent predictors of sICH and constituted the Time-Alberta Stroke Program Early CT-Glycemia-EVF score. Time-Alberta Stroke Program Early CT-Glycemia-EVF score was associated with an increased risk of sICH in the derivation cohort (OR increase per unit, 1.99 [95% CI, 1.53-2.59]; P<0.001) with area under the curve, 0.832 [95% CI, 0.767-0.898]. The score had good performance in the validation cohort (area under the curve, 0.801 [95% CI, 0.69-0.91]). CONCLUSIONS: Time-Alberta Stroke Program Early CT-Glycemia-EVF score is a simple tool with readily available clinical variables with good performances for sICH prediction after mechanical thrombectomy. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT01062698.

Small vessel disease and collaterals in ischemic stroke patients treated with thrombectomy.

BACKGROUND AND PURPOSE: To determine the influence of the cerebral small vessel disease (SVD) burden on collateral recruitment in patients treated with mechanical thrombectomy (MT) for anterior circulation acute ischemic stroke (AIS). METHODS: Patients with AIS due to large vessel occlusion (LVO) from the Thrombectomie des Artères Cérébrales (THRACE) trial and prospective cohorts from 2 academic comprehensive stroke centers treated with MT were pooled and retrospectively analyzed. Collaterals' adequacy was assessed using the American Society of Interventional and Therapeutic Radiology/Society of Interventional Radiology (ASITN/SIR) score on initial digital subtraction angiography and dichotomized as good (3,4) versus poor (0-2) collaterals. The SVD burden was rated with the global SVD score on MRI. Multivariable logistic regression analyses were used to determine relationships between SVD and ASITN/SIR scores. RESULTS: A total of 312 participants were included (53.2% males, mean age 67.8 ± 14.9 years). Two hundred and seven patients had poor collaterals (66.4%), and 133 (42.6%) presented with any SVD signature. In multivariable analysis, patients demonstrated worse leptomeningeal collaterality with increasing SVD burden before and after adjustment for SVD risk factors (adjusted odds ratio [aOR] 0.69; 95%CI [0.52-0.89] and aOR 0.66; 95%CI [0.5-0.88], respectively). Using individual SVD markers, poor collaterals were significantly associated with the presence of lacunes (aOR 0.40, 95% CI [0.20-0.79]). CONCLUSION: Our study provides evidence that in patients with AIS due to LVO treated with MT, the burden of SVD assessed by pre-treatment MRI is associated with poorer recruitment of leptomeningeal collaterals.

Pre-treatment lesional volume in older stroke patients treated with endovascular treatment.

BACKGROUND: Recent studies in the general stroke population treated with endovascular treatment (EVT) reported that higher pre-treatment lesional volumes were independently associated with poor neurological outcome and functional dependence after stroke. However, it has been not evaluated in older patients. AIM: We test the association between the pre-treatment lesional volume on diffusion-weighted magnetic resonance imaging and relevant outcome measures in older adults with stroke treated with EVT. METHODS: We included consecutive older adults with stroke (⩾80 years old) treated with EVT in two academic comprehensive stroke centers. The association between pre-treatment lesional volume and relevant outcome measures (poor outcome (modified Rankin scale 4-6), 3-month mortality and symptomatic intracerebral hemorrhage (sICH)) was evaluated using univariate and multivariable models. RESULTS: Five hundred seventy-nine patients were included (mean age: 85.6 ± 4.1, median lesional volume was 10 ml; interquartile range: 3-30 ml). Pre-treatment lesional volume was associated with poor functional outcome (adjusted odds ratio (aOR): 1.87, 95% confidence interval (CI): 1.60-2.20, for +1 logarithmic increase of lesional volume), 3-month mortality (aOR: 1.50, CI: 1.28-1.76), and sICH (aOR: 1.67, CI: 1.27-2.20). A threshold lesional volume >35 ml predicted 90% of patients with poor functional outcome and a cut-off >51 ml predicted 90% of patients dead at 3 months. CONCLUSIONS: Pre-treatment lesional volume might contribute, in association with other relevant clinical features, to the selection of older stroke patients who will benefit from EVT.

Endovascular Thrombectomy for Distal Medium Vessel Occlusions of the Middle Cerebral Artery: A Safe and Effective Procedure.

BACKGROUND: Distal medium vessel occlusions (DMVOs) are increasingly recognized as a next target for endovascular thrombectomy (EVT). Our objective was to investigate safety and clinical outcomes of EVT for DMVO of the middle cerebral artery (MCA). METHODS: We analyzed data of the Lille Reperfusion Registry from January 2017 to September 2020. Patients with a primary or secondary DMVO of the MCA seen on pretreatment angiogram were included. Only patients with a eTICI score 2b50-2b67 on initial angiogram were considered. Baseline characteristics, angiographic clinical, and safety outcomes were compared between patients treated with EVT or standard medical treatment (no-EVT). RESULTS: Of the 171 patients included, 96 received EVT (46.9% male, 68.7 ± 15.8 years) and 75 received standard medical treatment (44% male, 73.9 ± 13.1 years). EVT patients had a better improvement of the NIHSS score at discharge (adjusted mean difference: 3.71; 95% CI: 1.18-6.24). In the distal M2 occlusions subgroup, EVT was significantly associated with a higher rate of early neurologic improvement (adjusted OR: 3.62 95% CI: 1.31-10.03), NIHSS improvement at discharge (adjusted mean difference: 5.23; 95% CI: 2.18-8.29), and improved modified Rankin Scale score at 3 months (adjusted common OR for 1 point improvement: 3.06; 95% CI: 1.30 to 7.23). Symptomatic intracranial hemorrhage occurred in 3.1% in the EVT group and in 9.5% in the no-EVT group. CONCLUSIONS: EVT for DMVO of the MCA appears to be safe and may lead to improved clinical outcomes. This effect was especially pronounced in patients with distal M2 occlusions, warranting randomized trials to validate this result.

Non-ischemic cerebral enhancing lesions after intracranial aneurysm endovascular repair: a retrospective French national registry.

BACKGROUND: Non-ischemic cerebral enhancing (NICE) lesions are exceptionally rare following aneurysm endovascular therapy (EVT). OBJECTIVE: To investigate the presenting features and longitudinal follow-up of patients with NICE lesions following aneurysm EVT. METHODS: Patients included in a retrospective national multicentre inception cohort were analysed. NICE lesions were defined, using MRI, as delayed onset punctate, nodular or annular foci enhancements with peri-lesion edema, distributed in the vascular territory of the aneurysm EVT, with no other confounding disease. RESULTS: From a pool of 58 815 aneurysm endovascular treatment procedures during the study sampling period (2006-2019), 21/37 centres identified 31 patients with 32 aneurysms of the anterior circulation who developed NICE lesions (mean age 45±10 years). Mean delay to diagnosis was 5±9 months, with onset occurring a month or less after the index EVT procedure in 10 out of 31 patients (32%). NICE lesions were symptomatic at time of onset in 23 of 31 patients (74%). After a mean follow-up of 25±26 months, 25 patients (81%) were asymptomatic or minimally symptomatic without disability (modified Rankin Scale (mRS) score 0-1) at last follow-up while 4 (13%) presented with mild disability (mRS score 2). Clinical follow-up data were unavailable for two patients. Follow-up MRI (available in 27 patients; mean time interval after onset of 22±22 months) demonstrated persistent enhancement in 71% of cases. CONCLUSIONS: The clinical spectrum of NICE lesions following aneurysm EVT therapy spans a wide range of neurological symptoms. Clinical course is most commonly benign, although persistent long-term enhancement is frequent.

Safety and outcomes of endovascular treatment in patients with very severe acute ischemic stroke.

BACKGROUND: Patients with anterior circulation ischemic strokes due to large vessel occlusion (AIS-LVO) and very severe neurological deficits (National Institutes of Health Stroke Scale (NIHSS) score > 25) were under-represented in clinical trials on endovascular treatment (EVT). We aimed to evaluate safety and outcomes of EVT in patients with very severe vs. severe (NIHSS score 15-25) neurological deficits. METHODS: We included consecutive patients undergoing EVT for AIS-LVO between January 2015 and December 2019 at Lille University Hospital. We compared rates of parenchymal hemorrhage (PH), symptomatic intracranial hemorrhage (SICH), procedural complications, and 90-day mortality between patients with very severe vs. severe neurological deficit using univariable and multivariable logistic regression analyses. Functional outcome (90-days modified Rankin Scale) was compared between groups using ordinal logistic regression analysis. RESULTS: Among 1484 patients treated with EVT, 108 (7%) had pre-treatment NIHSS scores > 25, 873 (59%) with NIHSS scores 15-25 and 503 (34%) with NIHSS scores < 15. Rates of PH, SICH, successful recanalization, and procedural complications were similar in patients with NIHSS scores > 25 and NIHSS 15-25. Patients with NIHSS > 25 had a lower likelihood of improved functional outcome (adjcommon OR 0.31[95% CI 0.21-0.47]) and higher odds of mortality at 90 days (adjOR 2.3 [95% CI 1.5-3.7]) compared to patients with NIHSS 15-25. Successful recanalization was associated with better functional outcome (adjcommon OR 3.8 [95% CI 1.4-10.4]), and lower odds of mortality (adjOR 0.3 [95% CI 0.1-0.9]) in patients with very severe stroke. The therapeutic effect of recanalization on functional outcome and mortality was similar in both groups. CONCLUSIONS: In patients with very severe neurological deficit, EVT was safe and successful recanalization was strongly associated with better functional outcome at 90 days.

Carotid artery direct access for mechanical thrombectomy: the Carotid Artery Puncture Evaluation (CARE) study.

BACKGROUND: In acute ischemic stroke due to anterior large vessel occlusion (AIS-LVO), accessing the target occluded vessel for mechanical thrombectomy (MT) is sometimes impossible through the femoral approach. We aimed to evaluate the safety and efficacy of direct carotid artery puncture (DCP) for MT in patients with failed alternative vascular access. METHODS: We retrospectively analyzed data from 45 stroke centers in France, Switzerland and Germany through two research networks from January 2015 to July 2019. We collected physician-centered data on DCP practices and baseline characteristics, procedural variables and clinical outcome after DCP. Uni- and multivariable models were conducted to assess risk factors for complications. RESULTS: From January 2015 to July 2019, 28 149 MT were performed, of which 108 (0.39%) resulted in DCP due to unsuccessful vascular access. After DCP, 77 patients (71.3%) had successful reperfusion (modified Thrombolysis In Cerebral Infarction (mTICI) score ≥2b) and 28 (25.9%) were independent (modified Rankin Scale (mRS) score 0-2) at 3 months. 20 complications (18.5%) attributed to DCP occurred, all of them during or within 1 hour of the procedure. Complications led to extension of the intubation time in the intensive care unit in 7 patients (6.4%) and resulted in death in 3 (2.8%). The absence of use of a hemostatic closure device was associated with a higher complication risk (OR 3.04, 95% CI 1.03 to 8.97; p=0043). CONCLUSION: In this large multicentric study, DCP was scantly performed for vascular access to perform MT (0.39%) in patients with AIS-LVO and had a high rate of complications (18.5%). Our results provide arguments for not closing the cervical access by manual compression after MT.

Mechanical Thrombectomy in Patients with a Large Ischemic Volume at Presentation: Systematic Review and Meta-Analysis.

The benefits of mechanical thrombectomy (MT) for patients with acute ischemic stroke (AIS) and a large ischemic core (LIC) at presentation are uncertain. We aimed to obtain up-to-date aggregate estimates of the outcomes following MT in patients with volumetrically assessed LIC. We conducted a Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA)-conformed, PROSPERO-registered, systematic review and meta-analysis of studies that included patients with AIS and a baseline LIC treated with MT, reported ischemic core volume quantitatively, and included patients with a LIC defined as a core volume ≥50 mL. The search was restricted to studies published between January 2015 and June 2020. Random-effects-meta-analysis was used to assess the effect of MT on 90-day unfavorable outcome (i.e., modified Rankin Scale [mRS] 3-6), mortality, and symptomatic intracranial hemorrhage (sICH) occurrence. Sensitivity analyses were performed for imaging-modality (computed tomography-perfusion or magnetic resonance-diffusion weighted imaging) and LIC-definition (≥50 or ≥70 mL). We analyzed 10 studies (954 patients), including six (682 patients) with a control group, allowing to compare 332 patients with MT to 350 who received best-medical-management alone. Overall, after MT the rate of patients with mRS 3-6 at 90 days was 74% (99% confidence interval [CI], 67 to 84; Z-value=7.04; I2=92.3%) and the rate of 90-day mortality was 36% (99% CI, 33 to 40; Z-value=-7.07; I2=74.5). Receiving MT was associated with a significant decrease in mRS 3-6 odds ratio (OR) 0.19 (99% CI, 0.11 to 0.33; P<0.01; Z-value=-5.92; I2=62.56) and in mortality OR 0.60 (99% CI, 0.34 to 1.06; P=0.02; Z-value=-2.30; I2=58.72). Treatment group did not influence the proportion of patients experiencing sICH, OR 0.96 (99% CI, 0.2 to 1.49; P=0.54; Z-value=-0.63; I2=64.74). Neither imaging modality for core assessment, nor LIC definition influenced the aggregated outcomes. Using aggregate estimates, MT appeared to decrease the risk of unfavorable functional outcome in patients with a LIC assessed volumetrically at baseline.