Anterior Circulation Acute Ischemic Stroke Research Articles

The risk and outcome of malignant brain edema in post-mechanical thrombectomy: acute ischemic stroke by anterior circulation occlusion

Background and purposeMalignant brain edema (MBE) occurring after mechanical thrombectomy (MT) in acute ischemic stroke (AIS) could lead to severe disability and mortality. We aimed to investigate the incidence, predictors, and clinical outcomes of MBE in patients with AIS after MT.MethodsThe clinical and imaging data of 155 patients with AIS of anterior circulation after MT were studied. Standard non-contrast CT was used to evaluate baseline imaging characteristics at admission. Clinical outcomes were measured using the 90-day modified Rankin Scale (mRS) score. Based on the follow-up CT scans performed within 72 h after MT, the patients were classified into MBE and non-MBE group. MBE was defined as a midline shift of ≥ 5 mm with signs of local brain swelling. Univariate and multivariate regression analyses were used to analyze the relationship between MBE and clinical outcomes and identify the predictors that correlate with MBE.ResultsMBE was observed in 19.4% of the patients who underwent MT and was associated with a lower rate of favorable 90-day clinical outcomes. Significant differences were observed in both MBE and non-MBE groups: baseline Alberta Stroke Program Early CT (ASPECT) score, hyperdense middle cerebral artery sign (HMCAS), baseline signs of early infarct, angiographic favorable collaterals, number of retrieval attempts, and revascularization rate. Multivariate analysis indicated that low baseline ASPECT score, absent HMCAS, angiographic poor collaterals, more retrieval attempt count, and poor revascularization independently influenced the occurrence of MBE in AIS patients with anterior circulation after MT.ConclusionMBE was associated with a lower rate of favorable 90-day clinical outcomes. Low baseline ASPECT score, absent HMCAS, angiographic poor collaterals, more retrieval attempt count and poor revascularization were independently associated with MBE after MT.

Distal placement of balloon guide catheter facilitates stent-retriever mechanical thrombectomy for acute ischemic stroke in the anterior circulation.

Although balloon guide catheters (BGCs) have been demonstrated to improve recanalization and functional outcomes by enabling proximal flow control and forced aspiration during mechanical thrombectomy (MT), the significance of the BGC location has been overlooked. We evaluated the impact of BGC location during MT for anterior circulation acute ischemic stroke (AIS). Patients were divided into the proximal and distal BGC groups according to the BGC tip location relative to the lower margin of the C1 vertebral body. Endovascular and clinical outcomes were compared between the two groups, including subgroup analyses of the two types of extracranial internal carotid artery (ICA) anatomy, categorized based on cerebral angiography. A total of 124 patients were analyzed, with 62 each in the proximal and distal BGC placement groups. The distal BGC group had higher rates of first-pass recanalization (FPR) (38.7% vs. 17.7%, P = 0.009) and favorable outcomes (64.5% vs. 46.8%, P = 0.047) with shorter procedure time (47.5min vs. 65min, P = 0.001) and fewer distal embolization (3.2% vs. 12.9%, P = 0.048) than the proximal BGC group. FPR was also more frequently achieved in the distal BGC group of patients with tortuous ICA (37.0% vs. 12.5%, P = 0.029). Multivariate analysis showed that distal BGC placement was an independent predictor of FPR (odds ratio, 3.092; 95% confidence interval, 1.326-7.210; P = 0.009). Distal BGC placement facilitates MT for AIS in the anterior circulation. Therefore, we suggest distal BGC placement to maximize the effect of thrombectomy, even for tortuous extracranial ICA.

Effect of chronic antiplatelet therapy on clinical outcomes of endovascular thrombectomy for treatment of acute ischemic stroke.

The objective of this study was to investigate the prognostic significance of chronic antiplatelet therapy (APT) usage in acute ischemic stroke (AIS) treated with endovascular thrombectomy (EVT). Long-term APT may enhance recanalization but may also predispose patients to an increased risk of hemorrhagic transformation. Weighted hospitalizations for anterior-circulation AIS treated with EVT were identified in a large United States claims-based registry. Baseline clinical characteristics and outcomes were compared between patients with and without chronic APT usage prior to admission. Multivariable logistic regression analysis was performed to assess adjusted associations between APT and study endpoints. This analysis identified 36,560 patients, of whom 8170 (22.3%) were on a chronic APT regimen prior to admission. These patients were older and demonstrated a higher burden of comorbid disease, but had similar stroke severity on presentation in comparison with those not on APT. On unadjusted analysis, patients with prior APT demonstrated higher rates of favorable outcomes (24.3% vs 21.5%, p < 0.001), lower rates of mortality (7.0% vs 10.1%, p < 0.001), and lower rates of any intracranial hemorrhage (ICH; 20.3% vs 24.2%, p < 0.001), but no difference in rates of symptomatic ICH (sICH). Following multivariable adjustment for baseline clinical characteristics including age, acute stroke severity, and comorbidity burden, prior APT was associated with favorable outcome (adjusted odds ratio [aOR] 1.21, 95% CI 1.17-1.24, p < 0.001) and a lower likelihood of mortality (aOR 0.73, 95% CI 0.70-0.77, p < 0.001), without an increased likelihood of ICH (any ICH aOR 0.84, 95% CI 0.81-0.87, p < 0.001; sICH aOR 0.92, 95% CI 0.82-1.03, p = 0.131). Retrospective evaluation of patients with AIS treated with EVT using registry-based data demonstrated an association of prior APT usage with favorable outcomes, without an increased risk of hemorrhagic transformation.

The collateral map: prediction of lesion growth and penumbra after acute anterior circulation ischemic stroke

ObjectivesThis study evaluated the collateral map’s ability to predict lesion growth and penumbra after acute anterior circulation ischemic strokes.MethodsThis was a retrospective analysis of selected data from a prospectively collected database. The lesion growth ratio was the ratio of the follow-up lesion volume to the baseline lesion volume on diffusion-weighted imaging (DWI). The time-to-maximum (Tmax)/DWI ratio was the ratio of the baseline Tmax > 6 s volume to the baseline lesion volume. The collateral ratio was the ratio of the hypoperfused lesion volume of the phase_FU (phase with the hypoperfused lesions most approximate to the follow-up DWI lesion) to the hypoperfused lesion volume of the phase_baseline of the collateral map. Multiple logistic regression analyses were conducted to identify independent predictors of lesion growth. The concordance correlation coefficients of Tmax/DWI ratio and collateral ratio for lesion growth ratio were analyzed.ResultsFifty-two patients, including twenty-six males (mean age, 74 years), were included. Intermediate (OR, 1234.5; p < 0.001) and poor collateral perfusion grades (OR, 664.7; p = 0.006) were independently associated with lesion growth. Phase_FUs were immediately preceded phases of the phase_baselines in intermediate or poor collateral perfusion grades. The concordance correlation coefficients of the Tmax/DWI ratio and collateral ratio for the lesion growth ratio were 0.28 (95% CI, 0.17–0.38) and 0.88 (95% CI, 0.82–0.92), respectively.ConclusionPrecise prediction of lesion growth and penumbra can be possible using collateral maps, allowing for personalized application of recanalization treatments. Further studies are needed to generalize the findings of this study.Clinical relevance statementPrecise prediction of lesion growth and penumbra can be possible using collateral maps, allowing for personalized application of recanalization treatments.Key Points• Cell viability in cerebral ischemia due to proximal arterial steno-occlusion mainly depends on the collateral circulation.• The collateral map shows salvageable brain extent, which can survive by recanalization treatments after acute anterior circulation ischemic stroke.• Precise estimation of salvageable brain makes it possible to make patient-specific treatment decision.

Impact of Collateral Circulation on Futile Endovascular Thrombectomy in Acute Anterior Circulation Ischemic Stroke.

Collateral circulation is associated with the differential treatment effect of endovascular thrombectomy (EVT) in acute ischemic stroke. We aimed to verify the ability of the collateral map to predict futile EVT in patients with acute anterior circulation ischemic stroke. This secondary analysis of a prospective observational study included data from participants underwent EVT for acute ischemic stroke due to occlusion of the internal carotid artery and/or the middle cerebral artery within 8 hours of symptom onset. Multiple logistic regression analyses were conducted to identify independent predictors of futile recanalization (modified Rankin scale score at 90 days of 4-6 despite of successful reperfusion). In a total of 214 participants, older age (odds ratio [OR], 2.40; 95% confidence interval [CI], 1.56 to 3.67; p<0.001), higher baseline National Institutes of Health Stroke Scale (NIHSS) scores (OR, 1.12; 95% CI, 1.04 to 1.21; p=0.004), very poor collateral perfusion grade (OR, 35.09; 95% CI, 3.50 to 351.33; p=0.002), longer door-to-puncture time (OR, 1.08; 95% CI, 1.02 to 1.14; p=0.009), and failed reperfusion (OR, 3.73; 95% CI, 1.30 to 10.76; p=0.015) were associated with unfavorable functional outcomes. In 184 participants who achieved successful reperfusion, older age (OR, 2.30; 95% CI, 1.44 to 3.67; p<0.001), higher baseline NIHSS scores (OR, 1.12; 95% CI, 1.03 to 1.22; p=0.006), very poor collateral perfusion grade (OR, 4.96; 95% CI, 1.42 to 17.37; p=0.012), and longer door-to-reperfusion time (OR, 1.09; 95% CI, 1.03 to 1.15; p=0.003) were associated with unfavorable functional outcomes. The assessment of collateral perfusion status using the collateral map can predict futile EVT, which may help select ineligible patients for EVT, thereby potentially reducing the rate of futile EVT.

The Functional Prognosis of Rescue Conscious Sedation During Mechanical Thrombectomy on Patients with Acute Anterior Circulation Ischemic Stroke: A Single-Center Retrospective Study.

Basedonreal-worldcase data, this study intends to explore and analyze the impact of rescue conscious sedation (CS) on the clinical outcomes of patients with anterior circulation acute ischemic stroke (AIS) receiving mechanical thrombectomy (MT). This retrospective study enrolled patientswith anterior circulation AIS who received MT and were treated with eithersingle local anesthesia (LA) or rescue CS during MT between January 2018 and October 2021. We used univariate and multivariate logistic regression methods to compare the impact of LA and CS on the clinical outcomes of patients with AIS who received MT, including the mRS at90days, the incidence of poststroke pneumonia (PSP), the incidence of symptomatic intracranial cerebral hemorrhage (sICH), and the mortality rate. We reviewed 314 patient cases with AIS who received MT. Of all patients, 164met our search criteria. Eighty-nine patients received LA, and 75 patients received rescue CS. There was no significant difference between the two groups in the 90-day good prognosis (45.3% vs. 51.7%, p = 0.418) and mortality (17.3% vs. 22.5%, p = 0.414). Compared with the LA group, the incidence of postoperative pneumonia in the rescue CS group (44% vs. 25.8%, p = 0.015) was more significant. Multivariate stepwise logistic regression analysis revealed that intraoperative remedial CS was independently associated with PSP following MT. Inasubgroup analysis, rescue CS wasfoundto significantly increase the incidence of PSP in patients with dysphagia (OR = 7.307, 95% CI 2.144-24.906, p = 0.001). AstheseverityoftheNational Institutes of Health Stroke Scale (NIHSS)increased, intraoperative rescue CS wasfoundtoincrease the risk of PSP (OR = 1.155, 95% CI 1.034-1.290, p = 0.011) by 5.1% compared to that of LA (OR = 1.104, 95% CI 1.013-1.204, p = 0.024). Compared to LA, rescue CS during MT doesnotsignificantly improve the 90days of good prognosis and reduce the incidence of sICH and mortality in patients with anterior circulation AIS. However, it has a significantlyincreased risk of poststroke pneumonia (PSP), particularly in patients with dysphagia.

Comparison between different referral strategies for acute ischemic stroke patients in a hub-spoke emergency stroke network: a real-world experience in south-east Lazio.

To describe different referral strategies for acute ischemic stroke (AIS) patients in a Hub-Spoke emergency stroke network with their incidence, time metrics and related outcomes. Referral paradigms were defined as follows: primary transfer to the comprehensive stroke center (CSC) from a remote region, called mothership (MS); secondary transfer to the CSC from a primary stroke center where intravenous thrombolysis was available, called drip and ship (DS); secondary transfer to the CSC from a community hospital where no reperfusion therapy was available, called ship and drip (SD); primary transfer to the CSC from its catchment area, called direct CSC (dCSC). Among 517 anterior circulation AIS patients treated with mechanical thrombectomy between 2015 and 2020, 16.6% of them were SD, in addition to the well-known referral paradigms of MS (21.8%) and DS (18.1%). This rate grew to 30% when only patients whose place of onset was outside the CSC catchment area were considered. In the SD group, onset to CSC and onset to groin were significantly longer (178±80 min vs. 102±60 min, p<0.001, and 277±77 min vs. 211±61 min, p<0.001, respectively), and the risk of any intracranial hemorrhage (ICH) was significantly higher (OR: 2.514; 95%CI: 1.18-5.35, p=0.017) compared to MS. In this hub-spoke stroke network, a high proportion of SD paradigm was found, which was associated with longer times to treatment and higher rates of any ICH. A closer cooperation between hospital stroke physicians, national health system staff, and paramedics is warranted to identify the most appropriate referral strategy for each patient.

Specific inflammatory profile of acute ischemic stroke patients with left atrial enlargement.

The inflammatory process underlying atrial myopathy may affect the inflammatory response activated in acute ischemic stroke (AIS). We aimed to assess whether left atrial enlargement (LAE) as a marker of atrial myopathy is associated with a different profile of circulating inflammatory markers in AIS patients. HIBISCUS-STROKE is a cohort study including anterior circulation AIS patients treated with mechanical thrombectomy following MRI. Ten circulating inflammatory markers were measured at admission and 6, 24, and 48 h after admission. LAE was defined as a left atrial volume index (LAVi) ≥34 ml/m2. A multiple logistic regression model was performed to detect an independent association between the area under the curve (AUC) of these markers and LAE. We included 143 patients. Of them, 85 (59.4%) had LAE. On univariable analysis, we found that patients with LAE had higher soluble form suppression of tumorigenicity 2 (sST2), soluble tumor necrosis factor receptor I (sTNFR1), and vascular cellular adhesion molecule-1 (VCAM-1) AUC, were older, mostly female, had a higher National Institutes of Health Stroke Scale (NIHSS) score and blood glucose level at admission, had more often hypertension, and a cardioembolic source of AIS, such as atrial fibrillation, while they were less frequently current smokers and had a lower rate of tandem occlusion than patients without LAE. On multivariable analysis, we found that among circulating inflammatory markers, only high VCAM-1 (OR: 9.13, 95% CI: 3.21-25.9) and sST2 (OR: 3.40, 95% CI: 1.68-6.86) AUC remained associated with LAE. High VCAM-1 and sST2 levels within the first 48 h are associated with LAE in AIS patients.

Safety and efficacy of endovascular recanalization in patients with mild anterior stroke due to large-vessel occlusion exceeding 24 hours

Background Endovascular recanalization (ER) has demonstrated efficacy as a treatment modality for patients presenting with acute ischemic stroke (AIS) caused by large-vessel occlusion (LVO) within a 24-hour timeframe. Nevertheless, the safety and effectiveness of ER in patients with a time of onset exceeding 24 h remain uncertain. Objective To evaluate the safety and efficacy of ER treatment for mild ischemic stroke beyond 24-h from symptom onset. Methods A retrospectively maintained database of mild AIS due to LVO from March2018 to September 2022 at a comprehensive stroke center was screened. Patients received ER or standard medical therapies (SMT) for anterior circulation AIS due to LVO > 24-h were selected. Results We included 47 LVO patients with mild AIS beyond 24-h who suffered neurological deterioration (ND). 34 of these patients underwent ER, the other 13 received SMT. The technical success rate of recanalization was 82.4% (28/34). Patients received ER had significantly lower NIHSS score at discharge and 90-day mRS score (p = 0.028, p = 0.037, respectively) compared to SMT. In addition, they had significantly lower 90-day recurrence of ischemic stroke and lower incidence of moderate-severe stroke (with a NIHSS score at least 5) (p = 0.037, p = 0.033). There were 4 patients (11.7%) had perioperative complications, and no symptomatic intracranial hemorrhage occurred. Conclusion ER treatment for mild AIS due to LVO encountered ND was generally safe and effective, even beyond 24-h, and resulted in a good prognosis and lower 90-day recurrence compared to SMT.

Immediate CT change after thrombectomy predicting symptomatic hemorrhagic transformation.

The prognostic value of contrast accumulation from noncontrast brain computed tomography (CT) conducted immediately after intra mechanical thrombectomy (MT) in patients with acute ischemic stroke to predict symptomatic hemorrhage was studied. Patients with acute ischemic stroke treated using MT between February 2015 and April 2019 were included. Contrast accumulation was defined as a high attenuation area observed on noncontrast brain CT conducted immediately after thrombectomy treatment, and the patients were categorized into (1) symptomatic hemorrhage, (2) asymptomatic hemorrhage, and (3) no hemorrhage according to the presence of hemorrhagic transformation and their clinical conditions. The pattern and extent of contrast accumulation were compared between patients with and without symptomatic hemorrhage. The maximal Hounsfield unit (HU) of cortical involvement in contrast accumulation was evaluated by calculating the sensitivity, specificity, odds ratio, and area under the receiver operating characteristic (ROC) curve. In total, 101 patients with anterior circulation acute ischemic stroke were treated by endovascular intervention. Nine patients developed symptomatic hemorrhage and 17 developed asymptomatic hemorrhage. Contrast accumulation was associated with all types of hemorrhagic transformation ( p < 0.01), and cortical involvement pattern was more frequently associated with symptomatic hemorrhage ( p < 0.01). The area under the ROC curve was 0.887. The sensitivity and specificity for HU > 100 in cortical involvement predicting symptomatic hemorrhage after endovascular treatment were 77.8% and 95.7%, respectively, with an odds ratio of 77.0 (95% CI, 11.94-496.50; p < 0.01). Cortical involvement of contrast accumulation with a maximal HU > 100 predicts symptomatic hemorrhage after endovascular reperfusion treatment.

Effect of atrial fibrillation on outcomes in patients with anterior circulation occlusion stroke receiving endovascular therapy.

Atrial fibrillation is one of the major risk factors of ischemic stroke. Endovascular thrombectomy (EVT) has become the standard treatment for acute ischemic stroke with large vessel occlusion. However, data regarding the impact of AF on the outcome of patients with acute ischemic stroke treated with mechanical thrombectomy are controversial. The aim of our study was to determine whether atrial fibrillation modifies the functional outcome of patients with anterior circulation acute ischemic stroke receiving EVT. We reviewed 273 eligible patients receiving EVT from January 2019 to January 2022 from 3 comprehensive Chinese stroke centers, of whom 221 patients were recruited. Demographics, clinical, radiological and treatment characteristics, safety outcomes, and functional outcomes were collected. Modified Rankin scale (mRS) score ≤ 2 at 90 days was defined as a good functional outcome. In our cohort, 79 patients (35.74%) were eventually found to have AF. Patients with AF were elder (70.08 ± 11.72 vs. 61.82 ± 13.48 years, p = 0.000) and less likely to be males (54.43 vs. 73.94%, p = 0.03). The significant reperfusion rate (modified thrombolysis in cerebral infarction 2b-3) was 73.42 and 83.80% in patients with and without AF, respectively (p = 0.064). The good functional outcome (90-day modified Rankin scale: 0 to 2) rate was 39.24 and 44.37% in patients with and without AF, respectively (p = 0.460) after adjusting multiple confounding factors. There was no difference in the presence of symptomatic intracerebral hemorrhage between the two groups (10.13 vs. 12.68%, p = 0.573). Despite their older age, AF patients achieved similar outcomes as non-AF patients with anterior circulation occlusion treated with endovascular therapy.

TESLA Trial: Rationale, Protocol, and Design

Background Mechanical thrombectomy has been shown to be effective in patients with acute ischemic stroke secondary to large‐vessel occlusion and small to moderate infarct volume. However, there are no randomized clinical trials for large‐core infarct volume comparing mechanical thrombectomy to medical therapy in the population selected based solely on noncontrast computed tomography brain scan. The TESLA (Thrombectomy for Emergent Salvage of Large Anterior Circulation Ischemic Stroke) randomized clinical trial is designed to address this clinical question. Methods The TESLA trial aim is to demonstrate the efficacy (3‐month and 1‐year disability following stroke) and safety of intraarterial mechanical thrombectomy in patients with large‐volume infarction assessed with a noncontrast computed tomography scan. The TESLA trial design is a prospective, randomized controlled, multicenter, open‐label, assessor‐blinded anterior circulation acute ischemic stroke trial with adaptive enrichment design, enrolling up to 300 patients. Patients with anterior circulation large‐vessel occlusion who meet the imaging and clinical eligibility criteria with a large‐core infarction on the basis of noncontrast computed tomography Alberta Stroke Program Early CT Score (2–5) adjudicated by a site investigator will be randomized in a 1:1 ratio to undergo intraarterial thrombectomy or best medical management up to 24 hours from last known well. Results The primary efficacy outcome is utility‐weighted modified Rankin Scale (mRS) score distribution at 90 days between the groups. The results will be based on an intention‐to‐treat analysis that will examine the Bayesian posterior probability that, adjusted for Alberta Stroke Program Early CT Score, patients with large‐core infarct volume treated with intra‐arterial thrombectomy have higher expected utility‐weighted mRS than those treated with best medical management alone. The primary safety outcome is the 90‐day death rate. Key secondary outcomes are dichotomized mRS 0 to 2 and 0 to 3 outcomes, ordinal mRS scores, and quality of life (EuroQol 5 Dimension 5 Level survey) at 90 days and 1 year, utility‐weighted mRS at 1 year, hemicraniectomy rate, and rate of 24‐hour symptomatic intracranial hemorrhage in both groups. Conclusion TESLA is a pragmatic trial, designed to address the unanswered question of the efficacy and safety of intra‐arterial thrombectomy in patients with large infarcts diagnosed by the site investigator only on noncontrast computed tomography scan secondary to anterior circulation large‐vessel occlusion up to 24 hours from stroke symptoms onset.

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

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. 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. 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.

Thrombectomy alone vs thrombectomy with over 2/3-dose intravenous thrombolysis pretreatment in the DIRECT-MT trial

BackgroundThe DIRECT-MT trial showed that endovascular thrombectomy (EVT) alone was noninferior to EVT preceded by intravenous alteplase. However, the infusion of intravenous alteplase was uncompleted before the initiation of EVT in most cases of this trial. Therefore, the additional benefit and risk of over 2/3-dose intravenous alteplase pretreatment remain to be assessed. MethodsWe assessed patients with acute anterior circulation ischemic stroke who received EVT alone or with over 2/3-dose intravenous alteplase pretreatment from the DIRECT-MT trial. Patients were assigned to the thrombectomy-alone group and the alteplase pretreatment group. The primary outcome was the distribution of modified Rankin Scale (mRS) at 90 days. The interaction of treatment allocation and collateral capacity was assessed. ResultsA total of 393 patients (thrombectomy alone: 315; alteplase pretreatment: 78) were identified. The thrombectomy alone was comparable with alteplase pretreatment prior to the thrombectomy on the distribution of mRS at 90 days without significant effect modification by collateral capacity (adjusted common odds ratio (acOR), 1.12; 95% CI, 0.72–1.74; adjusted P for interaction = 0.83). Successful reperfusion before thrombectomy and the number of passes in the thrombectomy alone group differed significantly from the alteplase pretreatment group (2.6% vs. 11.5%; corrected P = 0.02 and 2 vs. 1; corrected P = 0.003). There was no interaction between treatment allocation and collateral capacity on all outcomes. ConclusionsEVT alone and EVT preceded by over 2/3-dose intravenous alteplase might have equal efficacy and safety for patients with acute anterior circulation large vessel occlusion, except for successful perfusion before thrombectomy and the number of passes.

Comparison of two computed tomography perfusion post-processing software to assess infarct volume in patients with acute ischemic stroke.

We used two automated software commonly employed in clinical practice-Olea Sphere (Olea) and Shukun-PerfusionGo (PerfusionGo)-to compare the diagnostic utility and volumetric agreement of computed tomography perfusion (CTP)-predicted final infarct volume (FIV) with true FIV in patients with anterior-circulation acute ischemic stroke (AIS). In all, 122 patients with anterior-circulation AIS who met the inclusion and exclusion criteria were retrospectively enrolled and divided into two groups: intervention group (n = 52) and conservative group (n = 70), according to recanalization of blood vessels and clinical outcome (NIHSS) after different treatments. Patients in both groups underwent one-stop 4D-CT angiography (CTA)/CTP, and the raw CTP data were processed on a workstation using Olea and PerfusionGo post-processing software, to calculate and obtain the ischemic core (IC) and hypoperfusion (IC plus penumbra) volumes, hypoperfusion in the conservative group and IC in the intervention group were used to define the predicted FIV. The ITK-SNAP software was used to manually outline and measure true FIV on the follow-up non-enhanced CT or MRI-DWI images. Intraclass correlation coefficients (ICC), Bland-Altman, and Kappa analysis were used to compare the differences in IC and penumbra volumes calculated by the Olea and PerfusionGo software to investigate the relationship between their predicted FIV and true FIV. The IC and penumbra difference between Olea and PerfusionGo within the same group (p < 0.001) was statistically significant. Olea obtained larger IC and smaller penumbra than PerfusionGo. Both software partially overestimated the infarct volume, but Olea significantly overestimated it by a larger percentage. ICC analysis showed that Olea performed better than PerfusionGo (intervention-Olea: ICC 0.633, 95%CI 0.439-0.771; intervention-PerfusionGo: ICC 0.526, 95%CI 0.299-0.696; conservative-Olea: ICC 0.623, 95%CI 0.457-0.747; conservative-PerfusionGo: ICC 0.507, 95%CI 0.312-0.662). Olea and PerfusionGo had the same capacity in accurately diagnosing and classifying patients with infarct volume <70 ml. Both software had differences in the evaluation of the IC and penumbra. Olea's predicted FIV was more closely correlated with the true FIV than PerfusionGo's prediction. Accurate assessment of infarction on CTP post-processing software remains challenging. Our results may have important practice implications for the clinical use of perfusion post-processing software.

NT-proBNP Levels and Collateral Circulation Status in Patients with Acute Ischemic Stroke.

In this study, 326 hospitalized patients with acute anterior circulation ischemic stroke (AACIS) were included. A comparison of the clinical characteristics of those with and without AF was conducted. The Spearman rank correlation was used for the correlation analysis of plasma NT-proBNP level, regional leptomeningeal collateral (rLMC) score, and computed tomography perfusion (CTP) status in the AF and non-AF groups. An analysis of multivariate linear regression was used to determine how plasma NT-proBNP level, rLMC score, and CTP status influenced the score on the NIHSS. There was a greater plasma NT-proBNP level in the AF group compared with the non-AF group, an increased CTP volume (including CTP ischemic volume, CTP infarct core volume, and CTP ischemic penumbra volume (P = 0.002)), higher NIHSS score on admission, and lower rLMC score (P < 0.001 for the remaining parameters). A negative correlation exists between plasma NT-proBNP level and rLMC score (r = -0.156, P = 0.022), but a positive correlation exists between plasma NT-proBNP level and both CTP ischemic volume and CTP infarct core volume (r = 0.148, P = 0.003) in the AF group, but not in the non-AF group. Multivariate linear regression analysis demonstrated that NT-proBNP, CTP ischemic penumbra volume, and rLMC score were associated with NIHSS score, and NT-proBNP was positively associated with NIHSS scores (95% confidence interval (CI), 0.000-0.002; P = 0.004) in the AF group, whatever in the unadjusted model or adjusted models, but not in the nonlarge artery atherosclerosis (LAA) group. In AACIS patients with AF, NT-proBNP level negatively correlated with collateral status, positively with CTP ischemic volume, and positively with NIHSS score.

Outcomes After Endovascular Therapy With Procedural Sedation vs General Anesthesia in Patients With Acute Ischemic Stroke

General anesthesia and procedural sedation are common practice for mechanical thrombectomy in acute ischemic stroke. However, risks and benefits of each strategy are unclear. To determine whether general anesthesia or procedural sedation for anterior circulation large-vessel occlusion acute ischemic stroke thrombectomy are associated with a difference in periprocedural complications and 3-month functional outcome. This open-label, blinded end point randomized clinical trial was conducted between August 2017 and February 2020, with final follow-up in May 2020, at 10 centers in France. Adults with occlusion of the intracranial internal carotid artery and/or the proximal middle cerebral artery treated with thrombectomy were enrolled. Patients were assigned to receive general anesthesia with tracheal intubation (n = 135) or procedural sedation (n = 138). The prespecified primary composite outcome was functional independence (a score of 0 to 2 on the modified Rankin Scale, which ranges from 0 [no neurologic disability] to 6 [death]) at 90 days and absence of major periprocedural complications (procedure-related serious adverse events, pneumonia, myocardial infarction, cardiogenic acute pulmonary edema, or malignant stroke) at 7 days. Among 273 patients evaluable for the primary outcome in the modified intention-to-treat population, 142 (52.0%) were women, and the mean (SD) age was 71.6 (13.8) years. The primary outcome occurred in 38 of 135 patients (28.2%) assigned to general anesthesia and in 50 of 138 patients (36.2%) assigned to procedural sedation (absolute difference, 8.1 percentage points; 95% CI, -2.3 to 19.1; P = .15). At 90 days, the rate of patients achieving functional independence was 33.3% (45 of 135) with general anesthesia and 39.1% (54 of 138) with procedural sedation (relative risk, 1.18; 95% CI, 0.86-1.61; P = .32). The rate of patients without major periprocedural complications at 7 days was 65.9% (89 of 135) with general anesthesia and 67.4% (93 of 138) with procedural sedation (relative risk, 1.02; 95% CI, 0.86-1.21; P = .80). In patients treated with mechanical thrombectomy for anterior circulation acute ischemic stroke, general anesthesia and procedural sedation were associated with similar rates of functional independence and major periprocedural complications. ClinicalTrials.gov Identifier: NCT03229148.

Abstract Number ‐ 155: CT Perfusion May Optimize Selection Of Elderly Patients For Mechanical Stroke Thrombectomy

Introduction Prior studies have demonstrated that CT perfusion (CTP) may be used to select patients for mechanical stroke thrombectomy (MST) with acute ischemic stroke owing to major artery obstruction in the anterior circulation for up to 24 hours. There is limited data on CTP selection of elderly patients aged ≥ 90 years old. We aimed to examine whether selecting nonagenarians with CT perfusion (CTP) imaging would allow for better outcomes. Specifically we aimed to examine hypoperfusion intensity ratio (HIR) and early infarct growth rate (EIGR) to optimize MST selection of nonagenarians. Methods This is a single center retrospective study from a large academic medical center. Patients included were at least 90 years old, presented with an anterior circulation acute ischemic stroke due to large vessel occlusion (LVO) and were treated with mechanical stroke thrombectomy (MST) between January 2018 and April 2022. Patients without CT perfusion (CTP) imaging prior to MST and without complete data were excluded. HIR was defined as time to maximum (Tmax 10 seconds/ Tmax 6 seconds). EIGR was defined as (relative cerebral blood flow &lt; 30% / last known well to CTP). Primary outcome was modified Rankin Scale (mRS) at 90 days, analyzed using an ordinal regression analysis and adjusted for baseline mRS, NIHSS, and possible confounding variables identified in univariate analyses. Secondary outcomes were: excellent reperfusion (TICI ≥ 2C), procedural complications of MST and symptomatic intracranial hemorrhage (sICH). The secondary outcomes were analyzed using binomial logistic regressions in two blocks where confounding variables were entered first, followed by variables of interest: HIR and EIGR. Results During the study epoch 70 nonagenarians were treated with MST. After exclusions, 59 nonagenarians were analyzed in the study. Despite selecting patients with CTP, 35 (59.3%) of patients reached mortality at 90 days. Additionally, only 9 (15.3%) patients achieved mRS of 0 – 2 or baseline mRS (if baseline mRS &gt; 2) at 90 days. HIR was found to be correlated with 90 day mRS (shift to next worse mRS), adjusted odds ratio (aOR) = 14.41 [95%CI 1.16, 179.11] p = 0.04, but not EIGR, aOR = 0.98 [95%CI 0.90, 1.06], p = 0.58. Neither HIR nor EIGR were not associated with excellent reperfusion, p = 0.38 and p = 0.88, respectively. Patients with higher EIGR were more likely to experience proceduralcomplications, aOR = 1.16 [95%CI 1.03, 1.31], p = 0.01, but there was no difference in HIR, p = 0.28. Lastly, there were no differences in HIR or EIGR and sICH, p = 0.07 and p = 0.68, respectively. Conclusions Very elderly patients aged 90 years or older experienced high rates of mortality and low proportions of good outcomes at 90 days. Nonagenarians with better collaterals as measured by HIR may have better outcomes at 90 days. Additionally, nonagenarians with faster growing ischemic cores may be more likely to experience complications during MST.

Abstract Number: LBA16 Does Intracranial Hemorrhage Associated with Tenecteplase Occur Exclusively Within the Stroke Burden?

Introduction As IV tenecteplase (TNK) is becoming an alternative to IV alteplase in acute ischemic stroke (AIS), establishing the incidence of intracranial hemorrhage (ICH) complications is important. Given the higher fibrin specificity of TNK as compared to alteplase, our aim was to distinguish hemorrhage within the stroke burden versus spontaneous ICH in patients with AIS with TNK‐associated ICH. Methods Retrospective chart review of patients presenting from February 2020 to January 2022 with anterior circulation AIS to our comprehensive stroke center who received TNK was performed to evaluate for associated ICH. ECASS‐3 criteria was used to define hemorrhagic transformation and ICH score was used for primary, spontaneous ICH. Fisher exact test statistic was used to evaluate for significant differences in ASPECTS score, medium versus versus large vessel occlusion, angiographic recanalization, IV eptifibatide use, pre‐morbid antiplatelet use, and association with symptomatic versus asymptomatic hemorrhage. A benchmark less than 5% symptomatic ICH incidence was set based on historical alteplase rates within our network. Social science statistics software was used for data analysis. Results Out of 77 subjects who received TNK, 20.7% (n = 16) developed ICH, 9.1% (n = 7) of which were symptomatic ICH with a temporally‐related increase in NIHSS of at least 4 or greater. Seven subjects (43.75%) were male. Mean age was 73.38 (95% CI 65.92, 80.83). Median initial NIHSS was 16, 95% CI [11.74, 21.51]. Median ASPECTS was 9, 95% CI [8.74, 9.89]. Two subjects developed spontaneous, primary ICH (n = 1 symptomatic ICH, n = 1 non‐symptomatic ICH) in the absence of hemorrhagic transformation of ischemic stroke. No significant difference between subjects with asymptomatic hemorrhage versus symptomatic hemorrhage was found when comparing ASPECTS &gt; = 7 versus &lt; 7 (Fisher value = 1), angiographic recanalization (Fisher value = 1), use of IV eptifibatide (Fisher value = 1), pre‐morbid antiplatelet use (Fisher value = 0.13), or medium vessel occlusion (Fisher value = ‐0.63). Conclusions Expected rates of hemorrhagic transformation were higher in tenecteplase than our historical benchmark rate for alteplase. Spontaneous hemorrhage unrelated to ischemic stroke area were seen in 2 subjects without known hematological disorders. Larger, prospective studies are needed to validate safety of tenecteplase in real world settings.

DEEP MOVEMENT: Deep learning of movie files for management of endovascular thrombectomy

ObjectivesTreatment and outcomes of acute stroke have been revolutionised by mechanical thrombectomy. Deep learning has shown great promise in diagnostics but applications in video and interventional radiology lag behind. We aimed to develop a model that takes as input digital subtraction angiography (DSA) videos and classifies the video according to (1) the presence of large vessel occlusion (LVO), (2) the location of the occlusion, and (3) the efficacy of reperfusion.MethodsAll patients who underwent DSA for anterior circulation acute ischaemic stroke between 2012 and 2019 were included. Consecutive normal studies were included to balance classes. An external validation (EV) dataset was collected from another institution. The trained model was also used on DSA videos post mechanical thrombectomy to assess thrombectomy efficacy.ResultsIn total, 1024 videos comprising 287 patients were included (44 for EV). Occlusion identification was achieved with 100% sensitivity and 91.67% specificity (EV 91.30% and 81.82%). Accuracy of location classification was 71% for ICA, 84% for M1, and 78% for M2 occlusions (EV 73, 25, and 50%). For post-thrombectomy DSA (n = 194), the model identified successful reperfusion with 100%, 88%, and 35% for ICA, M1, and M2 occlusion (EV 89, 88, and 60%). The model could also perform classification of post-intervention videos as mTICI < 3 with an AUC of 0.71.ConclusionsOur model can successfully identify normal DSA studies from those with LVO and classify thrombectomy outcome and solve a clinical radiology problem with two temporal elements (dynamic video and pre and post intervention).Key Points• DEEP MOVEMENT represents a novel application of a model applied to acute stroke imaging to handle two types of temporal complexity, dynamic video and pre and post intervention.• The model takes as an input digital subtraction angiograms of the anterior cerebral circulation and classifies according to (1) the presence or absence of large vessel occlusion, (2) the location of the occlusion, and (3) the efficacy of thrombectomy.• Potential clinical utility lies in providing decision support via rapid interpretation (pre thrombectomy) and automated objective gradation of thrombectomy outcomes (post thrombectomy).