Acute Anterior Circulation Stroke Research Articles

Rapid identification and prognosis evaluation by dual-phase computed tomography angiography for stroke patients with a large ischemic region in the anterior circulation treated with endovascular thrombectomy

PurposeTo investigate the value of dual-phase head-and-neck computed tomography angiography (CTA) in assessing advantages and risks associated with mechanical thrombectomy for stroke with a large ischemic region in the anterior circulation within 6 h of onset.MethodsWe retrospectively analyzed the data of patients with acute occlusion of the internal carotid artery or middle cerebral artery-M1 segment. Baseline dual-phase CTA was performed for collateral grading using the 4-point visual collateral score (0, 0% filling; 1, >0% and ≤50% filling; 2, >50 and <100% filling; 3, 100% filling). The rates of modified Rankin score (MRS) ≤ 3 at 90 days, any intracranial hemorrhage (ICH) within 48 h, malignant cerebral edema within 24 h, and all-cause 90-day mortality were analyzed.ResultsAmong the 69 study patients, 15, 26, 17, and 11 patients had collateral grades of 0, 1, 2, and 3, respectively. At 90 days, the MRS was ≤3 in 0, 8.33, 29.41, and 36.36% of patients with grades 0, 1, 2, and 3, respectively. ICH incidence was 73.33, 57.69, 29.41, and 18.18% for grades 0, 1, 2, and 3, respectively, while the incidence of malignant brain edema was 100, 76.92, 35.29, and 0%, respectively. All-cause 90-day mortality was 53.33% for grade 0 and 30.77% for grade 1; no deaths occurred at grades 2 and 3.ConclusionCollateral grading based on dual-phase CTA enables simple and rapid preoperative evaluation prior to mechanical thrombectomy for acute anterior-circulation stroke with a large ischemic focus, particularly for patients presenting within the 6-h time window.

Blood-brain barrier disruption and hemorrhagic transformation in acute stroke before endovascular reperfusion therapy.

Early blood-brain barrier (BBB) disruption in patients with acute ischemic stroke (AIS) can be detected on perfusion computed tomography (PCT) images before undergoing reperfusion therapy. In this study, we aimed to determine whether early disruption of the BBB predicts intracranial hemorrhage transformation (HT) in patients with AIS undergoing endovascular therapy and further identify factors influencing BBB disruption. We retrospectively analyzed general clinical and imaging data derived from 159 consecutive patients with acute anterior circulation stroke who were admitted to the Department of Neurology of the First Hospital of Jilin University, and who underwent endovascular treatment between January 1, 2021, and March 31, 2023. We evaluated the relationship between BBB destruction and intracranial HT before endovascular reperfusion therapy and examined the risk factors for early BBB destruction. A total of 159 patients with assessable BBB leakage were included. The median (interquartile range, IQR) age was 63 (54-70) years, 108 (67.9%) patients were male, and the median baseline National Institutes of Health Stroke Scale (NHISS) score was 12 (10-15). Follow-up non-contrast computed tomography (NCCT) detected HT in 63 patients. After logistic regression modeling adjustment, we found that BBB leakage in the true leakage area was slightly more than 2-fold risk of HT (odds ratio [OR], 2.01; 95% confidence interval [CI] 1.02-3.92). Heart rate was also associated with HT (OR, 1.03, 95% CI, 1.00-1.05). High Blood-brain barrier permeability (BBBP) in the true leakage area was positively correlated with infarct core volume (OR, 1.03; 95% CI, 1.01-1.05). Early BBB destruction before endovascular reperfusion therapy was associated with HT, whereas high BBBP correlated positively with infarct core volume.

Endovascular Thrombectomy for Large Ischemic Strokes with ASPECTS 0-2: aMeta-analysis of Randomized Controlled Trials.

Randomized controlled trials (RCTs) demonstrated atreatment effect of endovascular thrombectomy in acute ischemic stroke with large infarct, commonly defined as an Alberta Stroke Program Early CT Score (ASPECTS) of 3-5. However, data on endovascular thrombectomy in patients with very low ASPECTS of 0-2 remain scarce. We conducted asystematic review and meta-analysis of RCTs comparing endovascular thrombectomy versus medical treatment alone in acute ischemic anterior circulation stroke with very large infarct, defined as ASPECTS of 0-2. The primary outcome was the shift toward better functional outcomes on the 90-day modified Rankin Scale (mRS). Random effects meta-analysis was performed using the generic inverse variance method. Literature research identified four RCTs which evaluated the treatment effect of endovascular thrombectomy for large infarcts and provided asubgroup analysis of the mRS shift in patients with ASPECTS of 0-2. The pooled analysis showed asignificant shift toward better 90-day mRS scores in favor of endovascular thrombectomy (pooled odds ratio, 1.62, 95% confidence interval, 1.29-2.04, P < 0.001). This meta-analysis suggests atreatment effect of endovascular thrombectomy in specific patients with very low ASPECTS of 0-2, challenging the use of ASPECTS for treatment selection in acute ischemic stroke due to large vessel occlusion. An individual patient meta-analysis of RCTs would strengthen evidence in the treatment of patients with ASPECTS of 0-2.

Abstract TP217: Thrombus Migration in Acute Ischemic Stroke Patients Receiving Mechanical Thrombectomy

Background: Thrombus migration is occasionally observed during mechanical thrombectomy in acute ischemic stroke patients. However, the factors influencing migration and its impact on imaging and clinical prognosis remain unclear. We investigated the clinical and imaging predictors of thrombus migration and to evaluate the corresponding outcomes. Methods: We retrospectively analyzed data from patients with acute anterior circulation (internal carotid artery, M1, M2) stroke who underwent mechanical thrombectomy at two comprehensive stroke centers. Thrombus migration was defined as any distal movement of the proximal end of the thrombus on digital subtraction angiography (DSA) compared to pre-interventional computed tomography (CT) angiography. A comprehensive imaging review was performed, including Alberta Stroke Program Early CT Score, hyperdense vessel sign on non-contrast CT, collateral flow grading on CT angiography and DSA. Univariate and multivariable logistic regression analyses were performed to determine the association between clinical and imaging parameters and thrombus migration. In addition, we compared clinical outcomes according to the presence of thrombus migration. Results: Of the 365 patients enrolled, thrombus migration was observed in 81 patients (22.2%). In 40 of these, the thrombus migrated beyond the vessel segment. In multivariable analysis, hyperdense vessel sign (adjusted odds ratio [aOR], 5.41; 95% CI 2.9-10.07), older age (aOR, 1.04; 95% CI, 1.01-1.08), and onset-to-image time (aOR 1.00; 95% CI 0.99-1.00) were associated with thrombus migration. In particular, thrombus migration is an independent predictor of first-pass effect (aOR 2.17; 95% CI, 1.15-4.1). However, there was no significant effect on functional outcome as measured by modified Rankin Scale at 3 months. Conclusions: In large-vessel occlusion stroke, the location of the thrombus may change before mechanical thrombectomy compared to pre-interventional angiographic imaging. The composition of the thrombus, as indicated by the hyperdense vessel sign, may influence its tendency to migrate. While thrombus migration is associated with a first-pass effect, it does not influence functional outcomes.

Clinical and imaging predictors for hemorrhagic transformation of acute ischemic stroke after endovascular thrombectomy.

Hemorrhagic transformation (HT) is a common complication of endovascular thrombectomy (EVT) in patients with acute ischemic stroke (AIS). Our study aims to investigate the clinical and imaging predictors of HT and symptomatic intracranial hemorrhage (sICH) in patients who underwent EVT. A retrospective analysis of 118 patients undergoing EVT for acute anterior circulation stroke was performed. Potential clinical and imaging predictors of all patients were collected and multivariate logistic regression was performed. The risk prediction system was constructed according to the multivariate logistic regression results. The incidence of HT and sICH after EVT were 46.6% and 15.3%, respectively. The multivariate logistic regression results showed that Alberta Stroke Program Early CT Score (ASPECTS) (p = .001, odds ratio [OR] = 0.367, 95% [confidence interval] CI, 0.201-0.670), collateral status (p<.001, OR = 0.117, 95% CI, 0.042-0.325), relative cerebral blood flow (CBF) ratio (p = .025, OR = 0.943, 95% CI, 0.895-0.993), and blood glucose on admission (p = .012, OR = 1.258, 95% CI, 1.053-1.504) were associated with HT. While for sICH, collateral circulation (p = .007, OR = 0.148, 95% CI, 0.037-0.589), ASPECTS (p = .033, OR = 0.510, 95% CI, 0.274-0.946), and blood glucose (p = .005, OR = 1.304, 95% CI, 1.082-1.573) were independent factors. The predictive model for HT after EVT was established, and the sensitivity and specificity of it were 90.9% and 79.4%, respectively, with the area under the curve of 90.0% (84.5%-95.4%). Collateral status, ASPECTS, relative CBF ratio, and blood glucose on admission were predictors for HT in AIS patients, while collateral status, ASPECTS, and blood glucose on admission were also predictors for sICH. In addition, the established predictive model showed good diagnostic value for prediction of HT after EVT.

Shorter Reperfusion Time in Stroke is Associated with Better Cognition.

Cognitive changes that result from cerebrovascular disease contribute to a poor functional outcome with reduced quality of life. Among patients undergoing endovascular therapy (EVT), we aim to assess cognitive function and evaluate the impact of reperfusion time in cognitive performance. Patients with acute right anterior circulation strokes that underwent EVT between January 2018 and August 2020 at Centro Hospitalar de Vila Nova de Gaia/Espinho, participated in the study. Modified treatment in cerebral infarction (mTICI) assessed the level of recanalization. Cognitive evaluation was assessed with Addenbrooke's Cognitive Examination revised (ACE-R). Multiple linear regression analyses were used to determine the association between time for recanalization and ACE-R. The level of significance adopted was 0.05. The mean age of participants was 71.5 (interquartile range [IQR] 62.0-78.2) years, and 50% (22) were women. The median time after stroke was 28.6 months (IQR 18.94-31.55). All patients in our sample had a successful level of recanalization with EVT (mTICI ≥ 2b). Time for recanalization showed an inverse association with the ACE-R (b = -0.0207, P = 0.0203). Also the mRS at 3 months had an inverse association with cognition (b = -5.2803, p = 0.0095). Level of education had a strong and direct relationship with ACE-R results (b = 3.0869, p < 0.0001). Longer time between stroke symptoms and recanalization with EVT in patients with right hemisphere ischemic stroke lead to lower ACE-R scores. Measures to improve door-to-recanalization time are also important for cognitive performance after ischemic stroke.

Increased Neuron-Specific Enolase Level Predicts Symptomatic Intracranial Hemorrhage in Patients with Ischemic Stroke Treated with Endovascular Treatment

Neuron-specific enolase (NSE), which is a highly specific marker for neurons, could be a predictor for prognosis in patients with symptomatic intracranial hemorrhage (sICH) with acute ischemic stroke who are receiving endovascular treatment (EVT). This study aimed to investigate the relationship between NSE and sICH in patients with acute anterior circulation stroke undergoing EVT. A total of 215 consecutive patients with acute stroke treated with EVT were included. Patients with stroke and acute anterior circulation occlusion, receiving EVT treated at our hospital, were enrolled between January 2017 and August 2021. NSE level was measured on arrival at the neurology intensive care unit after EVT. The patients were divided into 2 groups according to whether sICH was present. Univariate and multivariate analyses were performed. NSE level was also incorporated into the TAG score (modified Thrombolysis in Cerebral Infarction score, Alberta Stroke Program Early CT Score, and glucose level), which was developed as a scoring system to predict sICH, and the prediction capability was compared with the TAG score alone. Causal inference was performed using the package DoWhy in Python to evaluate the causal relationship between NSE and sICH. The area under the curve (AUC) value of NSE showed moderate accuracy, with an AUC value of 0.729 (95% confidence interval, 0.655-0.795; P < 0.001). The NSE cutoff value was set at 23.88 ng/mL. When the NSE level ≥23.88 ng/mL, the sensitivity was 58.33% and the specificity was 78.72% (P < 0.001). The AUC for the TAG+ NSE score was 0.801 compared with an AUC of 0.632 for the TAG score (Z= 2.034; P= 0.042). A causal inference model using the DoWhy library shows a proportional relationship between NSE and the diagnosis of sICH. This study is the first to show that increased NSE level is an independent predictor of sICH in patients with acute anterior circulation stroke who are undergoing endovascular treatment.

Early haemodynamic predictors of poor functional outcomes in patients with acute ischaemic stroke receiving endovascular therapy: a single-centre retrospective study in China.

Changes in cerebral haemodynamics following endovascular therapy (EVT) for large-vessel occlusion stroke may affect the outcomes of patients with acute ischaemic stroke (AIS); however, evidence supporting this belief is limited. This study aims to identify the early haemodynamic predictors of poor outcomes in patients with AIS caused by anterior circulation large-artery occlusion after undergoing EVT and to evaluate the usefulness of these indicators in predicting functional outcomes at 90 days. This retrospective study was conducted at a single academic hospital, using prospectively collected data. We enrolled adult patients with acute anterior circulation stroke who underwent EVT. Transcranial colour-coded sonography (TCCS) examinations of the recanalised and contralateral middle cerebral artery (MCA) were performed within 12 h after undergoing EVT. Haemodynamic indicators were analysed to determine their association with poor functional outcomes (modified Rankin Scale: 3-6) 90 days after stroke. Receiver operating characteristic (ROC) curves were used to evaluate the usefulness of haemodynamic indicators in predicting functional outcomes. In total, 108 patients (median age: 66 years; 69.4% males) were enrolled in this study. Complete recanalization was achieved in 93 patients (86.1%); however, 60 patients (55.6%) had a poor 90-day outcome. The peak systolic velocity (PSV) ratio, adjusted PSV ratio, mean flow velocity (MFV) ratio, and adjusted MFV ratio of the MCA were significantly higher in patients with poor prognosis than in patients with good prognosis (p<0.02). A multivariate logistic regression analysis showed that higher PSV ratio, adjusted PSV ratio, MFV ratio, and adjusted MFV ratio were independently associated with a poor 90-day outcomes (adjusted odds ratio: 1.11-1.48 for every 0.1 increase; p<0.03). Furthermore, adding the adjusted MFV ratio significantly improved the prediction ability of the basic model for the 90-day poor functional outcome using the ROC analysis, the areas under ROC curves increased from 0.75 to 0.85 (p=0.013). Early TCCS examination may help in predicting poor functional outcomes at 90 days in patients with AIS who underwent EVT. Moreover, combining novel TCCS indicators (adjusted MFV ratio) with conventional parameters improved the prediction ability of the base model.

Factors influencing the need for emergent conversion to general anesthesia during mechanical thrombectomy in acute anterior circulation stroke – A retrospective observational study

BackgroundEndovascular mechanical thrombectomy (EMT) for acute ischemic stroke can be conducted under conscious sedation (CS) or general anesthesia (GA). Emergency conversion from CS to GA during the procedure can occur, but its predictors and impact on clinical outcomes are not fully understood. MethodsA single centre retrospective analysis was conducted on 226 patients who underwent EMT for anterior circulation stroke. Two groups were identified: patients who completed the procedure under CS and those requiring emergency conversion to GA. The predictors of emergency conversion to GA and its impact on clinical outcomes were analyzed. ResultsForty-five patients (19.9%) required conversion to GA. Atrial fibrillation (OR 2.38; CI 1.09–5.22; p = 0.03) and prolonged duration of procedure (OR 1.02; CI 1.01–1.04; p < 0.001) were identified as the independent predictors of emergency conversion to GA. ConclusionPatients with atrial fibrillation and prolonged duration of procedure especially when utilizing combined aspiration-stent retriever or angioplasty/stenting techniques, had a higher likelihood of requiring emergency conversion to general anesthesia (GA).

The association between stress hyperglycemia and unfavorable outcomes in patients with anterior circulation stroke after mechanical thrombectomy.

Stress hyperglycemia is common in critical and severe diseases. However, few studies have examined the association between stress hyperglycemia and the functional outcomes of patients with anterior circulation stroke, after mechanical thrombectomy (MT), in different diabetes status. This study therefore aimed to determine the relationship between stress hyperglycemia and the risk of adverse neurological functional outcomes in anterior circulation stroke patients with and without diabetes after MT. Data of 408 patients with acute anterior circulation stroke treated with MT through the green-channel treatment system for emergency stroke at the First Affiliated Hospital of Jinan University between January 2016 and December 2020 were reviewed retrospectively. The stress hyperglycemia ratio (SHR) was calculated as fasting plasma glucose (mmol/L) divided by glycosylated hemoglobin (%). The patients were stratified into four groups by quartiles of SHR (Q1-Q4). The primary outcome was an excellent (nondisabled) functional outcome at 3 months after admission (modified Rankin Scale score of 0-1). The relationship between stress hyperglycemia and neurological outcome after stroke was assessed using multivariate logistic regression. After adjusting for potential confounders, compared with patients in Q1, those in Q4 were less likely to have an excellent outcome at 3 months (odds ratio [OR], 0.32, 95% confidence interval [CI], 0.14-0.66, p = 0.003), a good outcome at 3 months (OR, 0.41, 95% CI, 0.20-0.84, p = 0.020), and major neurological improvement (OR, 0.38, 95% CI, 0.19-0.73, p = 0.004). Severe stress hyperglycemia increased risks of 3-months all-cause mortality (OR, 2.82, 95% CI, 1.09-8.29, p = 0.041) and ICH (OR, 2.54, 95% CI, 1.21-5.50, p = 0.015). Stress hyperglycemia was associated with a reduced rate of excellent neurological outcomes, and increased mortality and ICH risks in patients with anterior circulation stroke after MT regardless of diabetes status.

Poor Internal Jugular Venous Outflow Is Associated with Poor Cortical Venous Outflow and Outcomes after Successful Endovascular Reperfusion Therapy.

Many patients show poor outcomes following endovascular reperfusion therapy (ERT), and poor cortical venous outflow is a risk factor for these poor outcomes. We investigated the association between the outflow of the internal jugular vein (IJV) and baseline cortical venous outflow and the outcomes after ERT. We retrospectively enrolled 78 patients diagnosed with an acute anterior circulation stroke and successful ERT. Poor IJV outflow on the affected side was defined as stenosis ≥50% or occlusion of ipsilateral IJV, and poor outflow of bilateral IJVs was defined as stenosis ≥50% or occlusion of both IJVs. Poor cortical venous outflow was defined as a cortical vein opacification score (COVES) of 0 on admission. Multivariate analysis showed that poor outflow of IJV on the affected side was an independent predictor for hemorrhagic transformation. The poor outflow of bilateral IJVs was an independent risk factor for poor clinical outcomes. These patients also had numerical trends of a higher incidence of symptomatic intracranial hemorrhage, midline shift >10 mm, and in-hospital mortality; however, statistical significance was not observed. Additionally, poor IJV outflow was an independent determinant of poor cortical venous outflow. For acute large vessel occlusion patients, poor IJV outflow is associated with poor baseline cortical venous outflow and outcomes after successful ERT.

Association of intravenous thrombolysis and pre-interventional reperfusion: a post hoc analysis of the SWIFT DIRECT trial

BackgroundA potential benefit of intravenous thrombolysis (IVT) before mechanical thrombectomy (MT) is pre-interventional reperfusion. Currently, there are few data on the occurrence of pre-interventional reperfusion in patients randomized to IVT...

An old thrombus may potentially identify patients at higher risk of poor outcome in anterior circulation stroke undergoing thrombectomy.

To investigate thrombus age and its association with clinical and procedural parameters in patients with acute ischemic stroke (AIS) due to anterior circulation occlusions. The thrombi of 107 consecutive AIS patients with occlusions in anterior circulation large-arteries were collected during mechanical recanalization. By hematoxylin-eosin staining analysis, thrombi were classified as fresh (< 3days) or old (≥ 3days) according to the hemosiderin positivity. Old thrombi were further classified as thrombi with focal hemosiderin or diffuse hemosiderin according to their predominant distribution. Neuro-interventional data and clinical outcomes were compared based on thrombus age. We identified fresh thrombi in 29 patients and old thrombi in 78 patients. Compared with patients with fresh thrombi, patients with old thrombi were associated with (i) a longer mechanical recanalization time (p = 0.027), (ii) a higher percentage of fibrin/platelets and leukocytes (all p = 0.02) and a lower percentage of erythrocytes (p = 0.001), and (iii) less favorable clinical outcomes at discharge (p = 0.019) and 90days later (OR = 2.76, 95% CI = 1.09-6.99, p = 0.032). Furthermore, 18 (16.8%) of all patients had focal hemosiderin in old thrombi, which was independently linked to a poor clinical outcome 90days later (adjusted OR = 5.37, 95% CI = 1.14-25.28, p = 0.034). The presence of old thrombi, particularly those with focal hemosiderin, may aid in identifying patients with acute ischemic anterior circulation stroke who are at a higher risk of poor clinical outcome at 3-month follow-up.

Endovascular Treatment of Tandem Atherosclerotic Cervical Internal Carotid Artery Occlusion in the Setting of Acute Ischemic Stroke.

Among tandem occlusions, atherosclerotic cervical internal carotid artery occlusion (ACICAO) can be technically challenging and associated with its unique complications. We evaluated our experience with endovascular treatment (EVT) of ACICAO in the setting of acute ischemic stroke. In total, 154 consecutive patients who underwent EVT for acute anterior circulation stroke at our institute were retrospectively reviewed. Patients with tandem ACICAO were analyzed in this study. Procedures, recanalization rates, complications, and prognoses were evaluated. Ten patients (6%) of all 154 patients had ACICAO. In nine (90%) of the 10 patients, cervical lesions were successfully crossed and intervened upon. Four patients underwent stenting and five underwent angioplasty alone, followed by intracranial procedure. Eight patients (80%) achieved successful recanalization following mechanical thrombectomy for intracranial occlusion. However, one patient had massive subarachnoid hemorrhage during the procedure and another patient developed massive intracranial hemorrhage after EVT, both after stenting. Four of the five patients who initially underwent angioplasty alone subsequently underwent staged endarterectomy or stenting for residual stenosis on or after the next day. The single patient in whom the cervical lesion could not be crossed and another with reocclusion after EVT underwent a rescue bypass procedure due to persistent ischemic symptoms. After 90days, four patients (40%) were functionally independent (modified Rankin scale score 0-2). Our experience suggests that EVT for ACICAO is technically feasible; however, it involves the potential risk of several significant complications. To avoid serious hemorrhagic complications, cervical lesions may be better treated with angioplasty alone first.

Cerebral hyperdensity on CT imaging (CTHD) post-reperfusion treatment in patients with acute cerebral stroke: understanding its clinical meaning.

To investigate the clinical meaning of brain parenchymal computed-tomography hyperdensities (CTHD) in patients treated of anterior circulation acute stroke with reperfusion therapy. Patients were retrospectively enrolled from three different hospitals. Brain CT scans were assessed at four time points: We recorded ASPECT scores of pre-treatment CTs, assessed ASPECT scores and the presence of CTHD on post-treatment CTs acquired within 24-30h and 24-72h, and examined a one-month CTs follow-up to determine the ischemic evolution of CTHD. We correlated the presence of CTHD with clinical and radiological data to define its predictive and prognostic factors. In total, 165 patients were evaluated. At post-treatment CTs acquired within 24-30h, 68 (41%) patients showed the presence of CTHD. On post-treatment CTs acquired within 24-72h, 43 (63%) of the CTHD showed hemorrhagic transformation. Sixty-five (95%) out of the 68 CTHD evolved in a final ischemic brain area. Multivariate statistical analysis identified puncture to recanalization time to be the only independent factors predicting the presence of CTHD (p = 0.045). The presence of CTHD at the first post-treatment CTs was an independent factor for clinical outcome determined with mRS scores at 3-month follow-up (p = 0.05). Outcomes were worse for hemorrhagic transformation at follow-up CTs compared to the ischemic evolution of the CTHD (p = 0.01). The presence of CTHD at CTs imaging acquired within 24-30h after reperfusion therapy is an independent prognostic factor of a worse clinical outcome, regardless of its ASPECT score at baseline CTs and of its hemorrhagic evolution.

Normobaric Hyperoxia Combined With Endovascular Treatment for Patients With Acute Ischemic Stroke: A Randomized Controlled Clinical Trial.

To investigate the safety and efficacy of normobaric hyperoxia (NBO) combined with endovascular treatment (EVT) in patients with acute ischemic stroke (AIS). In this single-center, proof-of-concept, assessor-blinded, randomized, controlled pilot study, patients with AIS in the acute anterior circulation with large vessel occlusion who had an indication for EVT were randomly assigned to the EVT group or the NBO + EVT group. The NBO + EVT group was given 100% oxygen through a face mask initiated before vascular recanalization (10L/min for 4 hours), while the EVT group was given room air. The primary endpoint was infarct volume measured by MRI within 24-48 hours after randomization. A total of 231 patients were screened, and 86 patients were randomized into a ratio of 1:1 (EVT group, n = 43; NBO + EVT group, n = 43). The median infarction volume of the NBO + EVT group at 24-48 hours after randomization was significantly smaller than that of the EVT group (median 20.1 vs 37.7 mL, p < 0.01). The median mRS score at 90 days was 2 for the NBO + EVT group when compared with 3 for the EVT group (adjusted value 1.8, 95% CI 1.3-4.2; p = 0.038). Compared with the EVT group, the NBO + EVT group had a lower incidence of symptomatic intracranial hemorrhagic (7% vs 12%), mortality (9% vs 16%), and adverse events (33% vs 42%); however, such a difference was not statistically significant. NBO in combination with EVT seems to be a safe and feasible treatment strategy that could significantly reduce infarct volume, improve short-term neurobehavioral test score, and enhance clinical outcomes at 90 days when compared with EVT alone in patients with AIS. These observations need to be further confirmed by a large, multicenter, randomized clinical trial. NCT03620370. This pilot study provides Class I evidence that NBO combined with standard EVT decreases infarction volume in patients with acute anterior circulation stroke.

Complicated Carotid Artery Plaques and Risk of Recurrent Ischemic Stroke or TIA

BackgroundComplicated nonstenosing carotid artery plaques (CAPs) are an under-recognized cause of stroke. ObjectivesThe purpose of this study was to determine whether complicated CAP ipsilateral to acute ischemic anterior circulation stroke (icCAP) are associated with recurrent ischemic stroke or transient ischemic attack (TIA). MethodsThe CAPIAS (Carotid Plaque Imaging in Acute Stroke) multicenter study prospectively recruited patients with ischemic stroke restricted to the territory of a single carotid artery. Complicated (AHA-lesion type VI) CAP were defined by multisequence, contrast-enhanced carotid magnetic resonance imaging obtained within 10 days from stroke onset. Recurrent events were assessed after 3, 12, 24, and 36 months. The primary outcome was recurrent ischemic stroke or TIA. ResultsAmong 196 patients enrolled, 104 patients had cryptogenic stroke and nonstenosing CAP. During a mean follow-up of 30 months, recurrent ischemic stroke or TIA occurred in 21 patients. Recurrent events were significantly more frequent in patients with icCAP than in patients without icCAP, both in the overall cohort (incidence rate [3-year interval]: 9.50 vs 3.61 per 100 patient-years; P = 0.025, log-rank test) and in patients with cryptogenic stroke (10.92 vs 1.82 per 100 patient-years; P = 0.003). The results were driven by ipsilateral events. A ruptured fibrous cap (HR: 4.91; 95% CI: 1.31-18.45; P = 0.018) and intraplaque hemorrhage (HR: 4.37; 95% CI: 1.20-15.97; P = 0.026) were associated with a significantly increased risk of recurrent events in patients with cryptogenic stroke. ConclusionsComplicated CAP ipsilateral to acute ischemic anterior circulation stroke are associated with an increased risk of recurrent ischemic stroke or TIA. Carotid plaque imaging identifies high-risk patients who might be suited for inclusion into future secondary prevention trials. (Carotid Plaque Imaging in Acute Stroke [CAPIAS]; NCT01284933)

Reader Response: Thrombectomy vs Medical Management in Low NIHSS Acute Anterior Circulation Stroke.

The study by Volny et al. adds to the recent literature showing similar outcomes between mechanical thrombectomy (MT) and medical management (MM) in patients with minor stroke.1 However, a closer look at most of these studies shows selection bias in included patients. A significantly higher proportion of patients undergoing thrombectomy had ICA/proximal M1 occlusions relative to M2 occlusions in patients selected for medical management. Further, there was an 8.6% (95% CI − 8.8% to 26.1%) higher rate of excellent outcome after mechanical thrombectomy in the propensity-matched group.

Author Response: Thrombectomy vs Medical Management in Low NIHSS Acute Anterior Circulation Stroke.

We thank Drs. Khunte and Malhotra for their comments on our study.1 As we have stated in the Discussion section of our article, onset-to-treatment times were not available for our analysis. But we agree that your hypothesis could certainly be true. We are not sure where you saw the increased hemorrhage rate reported in our artcicle because data on intracranial hemorrhages were unverifiable in the SITS-TBY registry and could not be evaluated for our study.1 Furthermore, the MR CLEAN Registry group published an article recently, which “found no evidence of an association of prior antiplatelet therapy with the risk of symptomatic intracranial hemorrhage after endovascular treatment, nor on functional outcome, reperfusion, or mortality.”2

Editors' Note: Thrombectomy vs Medical Management in Low NIHSS Acute Anterior Circulation Stroke

Patients with a low NIH Stroke Scale (NIHSS) score have been historically excluded from randomized clinical trials evaluating mechanical thrombectomy (MT), and therefore, the efficacy of intervention in patients with milder symptoms is less well established. In their pooled analysis of 3 prospective registries (n = 236 patients), Dr. Volny et al. compared patients according to treatment with MT vs medical management if they fit the following criteria: NIHSS ≤6; prestroke modified Rankin Scale (mRS) 0–2; occlusion of the internal carotid, or M1 or M2 middle cerebral arteries; and arrival within 12 hours of last known well. The investigators found no difference in the rate of the primary outcome, mRS 0–1 at 90 days, between MT and medically managed groups (62% vs 64%, p = 0.79). With propensity matching, there remained no significant difference in the proportion of patients achieving the primary outcome (absolute difference of 8.6%, 95%CI −8.8% to 26.1%). Hypothetically, if the patients with missing 90-day outcomes all achieved excellent functional outcome (n = 13)—“best-case scenario”—MT would have been significantly associated with excellent functional outcome as compared to medical management (17.6%, 95%CI 0.01%–35.4%). Drs. Malhotra and Khunte address other potential important factors that could have contributed to functional outcome, such as less frequent use of thrombolysis in the MT arm (suggesting that these patients had more delay in MT and, therefore, more progressive ischemic injury) and a higher proportion of patients with internal carotid and M1 occlusions treated with MT (suggesting potentially greater volume of brain tissue at risk of infarction). Drs. Zerna and Volny respond that some of the patient-level data were missing from the consolidated registries. For example, there are no time-to-treatment data in any data source and no data regarding CT angiography or other imaging findings from 1 of the 3 registries. Patients with a low NIH Stroke Scale (NIHSS) score have been historically excluded from randomized clinical trials evaluating mechanical thrombectomy (MT), and therefore, the efficacy of intervention in patients with milder symptoms is less well established. In their pooled analysis of 3 prospective registries (n = 236 patients), Dr. Volny et al. compared patients according to treatment with MT vs medical management if they fit the following criteria: NIHSS ≤6; prestroke modified Rankin Scale (mRS) 0–2; occlusion of the internal carotid, or M1 or M2 middle cerebral arteries; and arrival within 12 hours of last known well. The investigators found no difference in the rate of the primary outcome, mRS 0–1 at 90 days, between MT and medically managed groups (62% vs 64%, p = 0.79). With propensity matching, there remained no significant difference in the proportion of patients achieving the primary outcome (absolute difference of 8.6%, 95%CI −8.8% to 26.1%). Hypothetically, if the patients with missing 90-day outcomes all achieved excellent functional outcome (n = 13)—“best-case scenario”—MT would have been significantly associated with excellent functional outcome as compared to medical management (17.6%, 95%CI 0.01%–35.4%). Drs. Malhotra and Khunte address other potential important factors that could have contributed to functional outcome, such as less frequent use of thrombolysis in the MT arm (suggesting that these patients had more delay in MT and, therefore, more progressive ischemic injury) and a higher proportion of patients with internal carotid and M1 occlusions treated with MT (suggesting potentially greater volume of brain tissue at risk of infarction). Drs. Zerna and Volny respond that some of the patient-level data were missing from the consolidated registries. For example, there are no time-to-treatment data in any data source and no data regarding CT angiography or other imaging findings from 1 of the 3 registries.