Endovascular Recanalization Therapy Research Articles

Blood pressure variability and hemorrhagic transformation in patients with successful recanalization after endovascular recanalization therapy: A retrospective observational study.

Although blood pressure (BP) variability has been regarded as a risk factor for hemorrhagic transformation (HTF) after intravenous thrombolysis, its effect on HTF after endovascular recanalization therapy (ERT) remains to be elucidated. We aimed to study the relationship between BP variability and symptomatic intracerebral hemorrhage (sICH) after successful recanalization with ERT. A total of 211 patients with acute ischemic stroke and successful recanalization (thrombolysis in cerebral infarction 2b or 3) after ERT were included between January 2013 and May 2017. The BP data following ERT was obtained over the first 24 hours using parameters including mean, maximum, minimum, difference between maximum and minimum, standard deviation, coefficient of variation, successive variations, and time rate (TR) of BP variation for systolic BP (SBP) and diastolic BP. sICH was defined as parenchymal hemorrhage type 2 with neurological deterioration of 4 points of more on the National Institute of Health Stroke Scale. Among the included patients, 20 (9.5%) developed sICH after successful ERT. The parameters linked with BP fluctuation over time were significantly related to sICH. After adjusting for confounders, the TR of SBP (per 0.1 mmHg/min increase) variation was independently associated with sICH (odds ratio = 1.71, 95% confidence interval = 1.013-2.886). Time-related BP variability in the first 24 hours following successful ERT was more correlated with sICH than other absolute BP levels. This suggests that maintaining a stable BP may be an important factor in preventing sICH after successful ERT. Ann Neurol 2019;85:574-581.

Abstract WP1: Threshold Volume Associated With Higher Survival After Endovascular Recanalization Therapy of Acute Ischemic Stroke

Background and Purpose: Endovascular recanalization therapy (ERT) is becoming increasingly important in the management of acute ischemic stroke (AIS), but the hospital threshold volume for optimal ERT remains unknown. We investigated whether there was a correlation between hospital volume of ERT and risk-adjusted patient outcomes. Materials and Methods: From the National Health Insurance (NHI) claims data, we selected 11,745 AIS patients who underwent ERT from 2011 to 2015, in 111 hospitals. The outcome measures of the study were 30-day mortality, readmission rate, and symptomatic intracranial hemorrhage (ICH) rate. For each outcome measure, risk-adjusted mortality prediction models incorporating demographic variables, modified Charlson comorbidity index, and clinical stroke severity index (SSI) were built, and validated through a comparison with two independent hospital registry-based models. Hospitals were divided into quartiles and risk-adjusted outcomes of AIS cases were compared across the hospital quartile to confirm volume-outcome relationship (VOR) in ERT. Spline regression was performed to determine the volume threshold. Results: The mean AIS volume was 14.8 cases per hospital per year and the unadjusted means of outcome variables were mortality 11.6%, readmission 4.6%, and ICH rate 8.6%. The VOR was observed in the risk-adjusted 30-day mortality rate across all quartile groups, and in the ICH rate between the first and fourth quartiles ( p < 0.05). Volume threshold was 24 cases per year, which was estimated by examining the relative effect on the adjusted odds of outcome for an increase in hospital volume by 10 cases/year for a hospital of a given size. Conclusions: We found an association between hospital volume and outcomes, and we identified the volume threshold in ERT. Policies to ensure the implementation of the AIS volume threshold for hospitals performing ERT is needed.

Influence of Strategic Cortical Infarctions on Pupillary Function.

Objective: Cortical activity, including cognitive and emotional processes, may influence pupillary function. The exact pathways and the site of cortical pupillary innervation remain elusive, however. We investigated the effects of select cortical strokes, i.e. ischemic infarcts affecting the insular cortex and prefrontal eye field, on pupillary function.Methods: Seventy-four patients with acute ischemic stroke, consecutively admitted to our institution from March to July 2018, were assessed 24 h after endovascular recanalization therapy (i.e., day 2 after the stroke), using automated pupillometry. Stroke location and volume and clinical severity (estimated by the Alberta Stroke Program Early CT Score and National Institute of Health Stroke Scale) were recorded. We excluded patients with posterior circulation stroke, intracranial pathology other than ischemic stroke, midline shift on computed tomography exceeding 5 millimeters or a history of eye disease. Pupillometry data from 25 neurologically normal patients with acute myocardial infarction were acquired for control.Results: Fifty stroke patients after thrombectomy were included for analysis. Twenty-five patients (50%) had insular cortex or prefrontal eye field involvement (group 1, strategic infarcts); 25 patients had infarcts located in other cerebral areas (group 2, other infarcts). The pupillary light reflex, as measured by constriction velocity and maximal/minimal pupillary diameters, was within physiological limits in all patients, including controls. However, while pupillary size and constriction velocities were correlated in all subjects, the correlation of size and dilatation velocity was absent in right-hemispheric infarcts (left hemisphere infarcts, group 1 (r2 = 0.15, p = 0.04), group 2 (r2 = 0.41, p = 0.0007); right hemisphere infarcts, group 1 (r2 = 0.008, p = 0.69); group 2 (r2 = 0.12, p = 0.08); controls (r2 = 0.29, p ≤ 0.0001).Conclusions: Cortical infarcts of the prefrontal eye field or insula do not impair the pupillary light reflex in humans. However, subtle changes may occur when the pupils dilate back to baseline, probably due to autonomic dysfunction. Replication is needed to explore the possible influence of hemispheric lateralization. We suggest that endovascular therapy for acute ischemic stroke may serve as a clinical research model for the study of acquired cortical lesions in humans.

An Update of Recent Guideline for the Endovascular Recanalization Therapy in Acute Ischemic Stroke

An Update of Recent Guideline for the Endovascular Recanalization Therapy in Acute Ischemic Stroke

Procedural and clinical outcomes of endovascular recanalization therapy in patients with cancer-related stroke

Objective Embolism due to coagulopathy might be the main pathomechanism underlying cancer-related stroke (CRS). CRS patients with a large artery occlusion could be candidates for endovascular recanalization therapy (ERT), although its procedural and clinical outcomes are not well known. This study aimed to investigate the procedural and clinical outcomes of ERT in CRS patients and the characteristics associated with outcomes compared with those of conventional stroke patients. Methods A registry of consecutive acute ischemic stroke patients who underwent ERT between January 2011 and October 2015 was retrospectively reviewed. CRS patients are described as those who had (a) cryptogenic stroke with advanced or metastatic cancer; (b) no other possible causes of stroke such as cardioembolism (CE) and large artery atherosclerosis (LAA); and (c) elevated D-dimer levels or diffusion-restricted lesions in multiple vascular territories. We compared procedural and clinical outcomes at discharge among CRS, CE, and LAA patients. Results A total of 329 patients were finally enrolled in this study; of these, 19 were CRS patients. The rate of successful recanalization, defined as modified treatment in cerebral infarction grade 2b or 3, was lower in the CRS group than in the LAA and CE groups (63% versus 84% versus 84%, p = .06). CRS subtype was an independent predictor for successful recanalization after ERT in the multivariate analysis (odds ratio, 0.317; 95% confidence interval, 0.116-0.867; p < .001). No significant difference in the rate of good clinical outcomes at discharge was observed among groups. Conclusions Although clinical outcomes at discharge were similar for CE and LAA patients, complete recanalization seemed more difficult to achieve in CRS patients than in conventional stroke patients.

Endovascular Thrombectomy for Large-Vessel Occlusion Strokes with Preexisting Intracranial Aneurysms.

This study aimed to investigate the safety of endovascular thrombectomy in acute ischemic stroke with preexisting intracranial aneurysms. Patients with acute ischemic stroke due to large-artery occlusion combined with intracranial aneurysms, who received endovascular treatment, were analyzed retrospectively, and the procedure-related data were recorded. Among the 124 patients who suffered acute large-artery occlusion and received endovascular recanalization therapy, intracranial aneurysms were found in seven patients (5.6%). All the seven patients achieved successful recanalization, except one patient who suffered subarachnoid hemorrhage due to the rupture of aneurysm during the procedure. The prevalence of preexisting cerebral aneurysms in patients with acute ischemic stroke is high, leading to a procedure-related rupture risk. Endovascular treatment devices must be used carefully in these patients, especially when the aneurysms are located within the area where the procedure is performed.

Posttreatment National Institutes of Health Stroke Scale Is Superior to the Initial Score or Thrombolysis in Cerebral Ischemia for 3-Month Outcome.

The majority of ischemic stroke patients receiving endovascular recanalization therapy (EVT) experience variable changes of neurological severities during the hyperacute period. We hypothesized that the National Institutes of Health Stroke Scale (NIHSS) score after EVT is a better prognostic factor compared with the initial NIHSS score or revascularization status. We identified 566 stroke patients who received EVT at Seoul National University Bundang Hospital between April 2008 and December 2015. We prospectively collected post-EVT NIHSS score, which was measured in the angiography suite by on-duty physicians after completion of EVT. Model 1 included baseline predictors including an initial NIHSS score. In model 2, 3, and 4, revascularization status, post-EVT NIHSS score, or both were additionally included. The discrimination powers for modified Rankin Scale score of 0 to 2 at 3 months were assessed using C statistic, integrated discrimination index, and category-free net reclassification index. The median of initial and post-EVT NIHSS score were 14 (9-19) and 11 (5-17) points, respectively (an improvement, 58.8%; no change, 20.7%; deterioration, 20.5%). A modified Rankin Scale score 0 to 2 at 3 months was achieved in 47%. Based on the results of differences among the C statistics, both model 3 and model 4 (C statistics: 0.896 and 0.906) showed significantly increased discrimination power for modified Rankin Scale score 0 to 2 at 3 months than the model 1 or 2 (C statistics: 0.802 and 0.834, P values<0.001 for all comparisons). Model 4 showed significant improvement of both integrated discrimination index and net reclassification index as compared with all other models, but the magnitude of improvement from model 3 to model 4 (integrated discrimination index, 0.021; net reclassification index, 0.322) was modest. Incorporation of post-EVT NIHSS score conferred better discrimination power to the statistical models for functional recovery. Post-EVT NIHSS score may be an appropriate baseline factor when evaluating an intervention after hyperacute period.

Endovascular treatment for the acute ischemic stroke: the past and the future

Occlusion of large arteries, such as terminal parts of internal carotid artery (ICA) and main stem of middle cerebral artery (MCA), often result in poor outcomes of the acute ischemic stroke (AIS) patients. Recently, randomized controlled trials (RCTs) have consistently confirmed the benefit of endovascular treatment in AIS patients. With the positive results of these studies, endovascular recanalization therapy has been recommended as standard stroke care by stroke guidelines. In this review, we describe the strategies of endovascular treatment, analyze the reasons of the superiority of the thrombectomy in recent trails. The therapeutic time window, better patient selection, expediting and enhancing recanalization, and the addition of neuroprotective agents are the important factors we should focus on in the future.

Clinical Characteristics of Patients with Embolic Stroke of Undetermined Source Treated by Endovascular Recanalization Therapy

Clinical Characteristics of Patients with Embolic Stroke of Undetermined Source Treated by Endovascular Recanalization Therapy

P2-5 - Endovascular recanalization therapy in the patients with acute ischemic stroke and active malignancy

P2-5 - Endovascular recanalization therapy in the patients with acute ischemic stroke and active malignancy

P4-6 - Outcomes of endovascular recanalization therapy for elderly patients with acute ischemic stroke

【Introduction】Mechanical thrombectomy has been proven effective and the number of elderly patients with acute ischemic stroke (AIS) receiving thrombectomy is expected to increase. We examined thrombectomy outcomes in elderly patients treated for AIS.

Update of the Korean Clinical Practice Guidelines for Endovascular Recanalization Therapy in Patients with Acute Ischemic Stroke

Patients with severe stroke due to acute large cerebral artery occlusion are likely to be severely disabled or dead without timely reperfusion. Previously, intravenous tissue plasminogen activator (IV-TPA) within 4.5 hours after stroke onset was the only proven therapy, but IV-TPA alone does not sufficiently improve the outcome of patients with acute large artery occlusion. With the introduction of the advanced endovascular therapy, which enables more fast and more successful recanalization, recent randomized trials consecutively and consistently demonstrated the benefit of endovascular recanalization therapy (ERT) when added to IV-TPA. Accordingly, to update the recommendations, we assembled members of the writing committee appointed by the Korean Stroke Society, the Korean Society of Interventional Neuroradiology, and the Society of Korean Endovascular Neurosurgeons. Reviewing the evidences that have been accumulated, the writing members revised recommendations, for which formal consensus was achieved by convening a panel composed of 34 experts from the participating academic societies. The current guideline provides the evidence-based recommendations for ERT in patients with acute large cerebral artery occlusion regarding patient selection, treatment modalities, neuroimaging evaluation, and system organization.

Heads Up! A Novel Provocative Maneuver to Guide Acute Ischemic Stroke Management

Background: A common dilemma in acute ischemic stroke management is whether to pursue recanalization therapy in patients with large vessel occlusions but minimal neurologic deficits. We describe and report preliminary experience with a provocative maneuver, i.e. 90-degree elevation of the head of bed for 30 min, which stresses collaterals and facilitates decision-making. Methods: A prospective cohort study of <7.5 h of acute anterior circulation territory ischemia patients with minimal deficits despite middle cerebral artery (MCA) or internal carotid artery (ICA) occlusive disease. Results: Five patients met the study entry criteria. Their mean age was 78.4 years (range 65-93). All presented with substantial deficits (median NIHSS score 11, range 5-22), but improved while in supine position during initial imaging to normal or near-normal (NIHSS score 0-2). MRA showed persistent M1 MCA occlusions in 4, critical ICA stenosis or occlusion in 1, and substantial perfusion-diffusion mismatch in all. To evaluate the potential for eventual collateral failure, patients were placed in a head of bed upright posture. Mean arterial pressure and heart rate were unchanged. Two showed no neurologic worsening and were treated with supportive care with excellent final outcome. Three showed worsening, including recurrent hemiparesis and aphasia at the 6th, recurrent aphasia at the 23rd, and recurrent hemineglect at the 15th upright minute. These 3 underwent endovascular recanalization therapies with successful reperfusion and excellent final outcome. Conclusion: The ‘Heads Up' test may be a useful, simple maneuver to assess the risk of collateral failure and guide the decision to pursue recanalization therapy in acute cerebral ischemia patients with minimal deficits despite persisting large cerebral artery occlusion.

Characteristics of the Drip-and-Ship Paradigm for Patients with Acute Ischemic Stroke in South Korea

Data on the drip-and-ship paradigm in Korea are limited. The present study aimed to evaluate the use of the drip-and-ship paradigm and the time delays and outcomes associated with the paradigm in Korea. We used data from the Clinical Research Center for Stroke-5 registry between January 2011 and March 2014. Among patients treated with tissue-type plasminogen activator (tPA), the use of the drip-and-ship paradigm was evaluated, and time delays and functional outcomes at 3 months were compared between patients treated with the paradigm and those treated directly at visits. Among 1843 patients who met the eligibility criteria, 244 patients (13.2%) were treated with the drip-and-ship paradigm. Subsequent endovascular recanalization therapy was used in 509 patients (27.6%). The median time from symptom onset to groin puncture was greater in patients treated with the paradigm than in those treated directly at visits (305 versus 200 minutes, P < .001). In multivariate analysis, the risks of unfavorable functional outcomes and symptomatic intracranial hemorrhage were higher inpatients treated with the paradigm than in those directly treated at visits (odds ratio [OR] 2.15; 95% confidence interval [CI], 1.50-3.08; P < .001 and OR 1.78; 95% CI, 1.02-3.12; P = .041, respectively). In Korea, the drip-and-ship paradigm was used in less than 15% of all patients treated with tPA. The use of the paradigm might cause an increase in the onset-to-groin puncture time. Additionally, clinical outcomes might be worse in patients treated with the paradigm than in those treated directly at visits.

Time to Presentation Is Associated with Clinical Outcome in Hemispheric Stroke Patients Deemed Ineligible for Recanalization Therapy

Delayed thrombolysis adversely impacts functional outcome after stroke. Therefore, great efforts are undertaken to reduce delay in patient presentation and initiate treatment as quickly as possible. However, little is known regarding the impact of time to presentation (TTP) on outcome in patients who are ineligible for acute stroke therapy. Thus, we sought to determine whether the TTP is associated with the 90-day outcome irrespective of eligibility for acute recanalization therapy. We retrospectively analyzed 258 consecutive acute ischemic stroke patients evaluated between January 2013 and February 2014. Multivariable logistic regression was used to determine whether a greater TTP is independently associated with a poor 90-day outcome defined as a modified Rankin scale (mRS) score of 3-6. In the unadjusted analyses, the TTP was inversely correlated with transfer from an acute facility (r = -.126, P = .043), cardioembolic stroke etiology (r = -.146, P = .019), and acute recanalization therapy (r = .-412, P < .001). Conversely, a longer TTP was correlated with a worse 90-day mRS score (r = .127, P = .045). After adjustment, the TTP (P = .019), age (P < .001), female sex (P = .001), National Institutes of Health Stroke Scale score (P < .001), preadmission mRS score (P = .001), atrial fibrillation (P < .001), and infarct volume (P < .001) were independently associated with a poor 90-day outcome. Importantly, a longer TTP (odds ratio 1.016, 95% confidence interval 1.001-1.032, P = .036) remained independently associated with the 90-day outcome when we restricted the analyses to patients ineligible for acute intravenous and endovascular recanalization therapies. Each hour delay in the TTP decreased chances for good outcome by approximately 2% independent of patient eligibility for acute recanalization therapies.

Differences in Effectiveness among Devices for Endovascular Thrombectomy in Patients with Acute Ischemic Stroke.

Differences in Effectiveness among Devices for Endovascular Thrombectomy in Patients with Acute Ischemic Stroke.

Abstract WP16: Endovascular Recanalization Therapy in Acute Ischemic Stroke: Updated Meta-analysis of Randomized Controlled Trials

Background: Recent randomized clinical trials (RCTs) using stent-retriever thrombectomy demonstrated clear and consistent benefit of endovascular recanalization therapy (ERT) in contrast to the negative result of earlier trials. We aimed to calculate the pooled estimate of the ERT benefit added to standard therapy in AIS. Methods: We systematically searched Pubmed and EMBASE until 31 Apr 2015. Inclusion criteria were 1) RCT, 2) the active arm receiving ERT, 3) the control arm receiving standard therapy including intravenous TPA, but not treated with ERT, and 4) mRS score reported at 90 days or at the end of the trial. Using a random-effect model, we generated a pooled estimate as an odds ratio (OR) with 95% CI for the effect of ERT regarding the efficacy and safety outcomes for all trials, stent-retriever trials, and RCTs comparing ERT and intravenous TPA. Results: We identified 15 relevant RCTs involving 2,899 patients. For all trials, ERT compared to control was associated with increased good outcome (OR [95% CI], 1.79 [1.34, 2.40]; P&lt;0.0001; number needed-to-treat [NNT]=9). ERT also increased outcomes of no or minimal disability, good neurological recovery, good activity of daily living, and recanalization. ERT was not associated with increased risks of symptomatic intracranial hemorrhage (SICH) (1.19 [0.83, 1.69]; P=0.3453; number needed-to-harm [NNH]=88) and death (0.87 [0.71, 1.05]; P=0.1508; NNT=55). On the contrary, ERT significantly reduced extreme disability or death (0.77 [0.61, 0.97]; P=0.0246; NNT=21). When restricting 5 stent-retriever RCTs which generally compared ERT added to intravenous TPA versus intravenous TPA alone, the benefit was even greater: 2.39 [1.88, 3.04], P&lt;0.0001, NNT=5 for good outcome; 0.57 [0.41, 0.78], P=0.0006, NNT=9 for extreme disability or death. Analysis restricting 8 RCTs comparing ERT (added to intravenous TPA in 6 RCTs) with intravenous TPA alone also showed similar efficacy and safety. Conclusions: This updated meta-analysis shows that ERT compared to the current standard therapy substantially improves good outcome and reduces extreme disability or death without significantly increasing SICH. Now, we are facing a new challenge how to provide ERT more and faster to eligible patients.

Abstract TP8: A Pilot Study of Selective Brain Cooling by Intra-arterial Infusion of Cold Saline in Acute Ischemic Stroke

Background and purpose: The neuroprotection of hypothermia in acute ischemic stroke has been proved by many animal experiments. However, the whole body cooling needs relatively longer time to reach target temperature and has many adverse effects. In this trial, we focused on the feasibility and safety of selective brain cooling by intra-arterial infusion of cold saline in patients with acute ischemic stroke during endovascular revascularization procedure. Methods: Patients who suffered from large proximal vessel occlusions within 8 hours after symptoms onset were enrolled. All patients received intra-arterial recanalization combined with infusion of isotonic saline (4°C) into ischemic territory through angiographic catheter. Vital signs, physiological parameters, adverse effects and complications were analyzed to evaluate feasibility and safety. Modified Rankin Scale (mRS) and mortality at 3 months were analyzed to evaluate clinical outcome. Results: 26 patients with a mean age of 58.4±9.56 years and median NIHSS score of 18 (14-20) were enrolled. The median time from symptoms onset to groin puncture was 383 (195-432) minutes. physiologic parameters were relatively stable before, during, and after revascularization procedures. The temperature of ischemic cerebral tissue was dropped at least 2°C theoretically during infusion of the cold solution, and rectal temperature was mildly dropped (maximum 0.3°C), but soon returned to normal after infusion. Complications in these patients included pneumonia (n=10), mild vascular spasm (n=4), melena (n=2), deep vein thrombosis (n=1), coagulation disorder (n=2). No intracranial hemorrhage, shivering, groin hematom, acute congestive heart failure, renal inadequacy, platelet count&lt;100 000/nL and arrhythmia were observed. At 3 months, 15 patients had good outcome (mRS, 0-2) and 11 patients with poor outcome (mRS, 3-6). Conclusions: Selective brain cooling by intra-arterial infusion of cold saline combined with endovascular recanalization therapy in acute ischemic stroke is feasible and safe.

Abstract TP304: Use, Time Delay and Outcomes of the Drip-and-Ship Thrombolysis Paradigm for Patients With Acute Ischemic Stroke

Introduction: The utilization of drip-and-ship thrombolysis paradigm, clinical characteristics and outcomes of patients treated with the paradigm could vary with regional stroke care system. Hypothesis: We hypothesized that clinical characteristics and functional outcomes of patients treated with drip-and-ship paradigm would be different from those of patients treated via direct visit. Methods: From a multicenter stroke registry, we identified acute ischemic stroke patients treated with tPA who arrived hospital within 6 hours from the symptom onset. Functional outcomes at three months after the stroke were classified as favorable (modified Rankin Scale score [mRS] 0 to 1) or unfavorable (mRS 2-6). Using multivariable analysis, we compared the modified Rankin scale (mRS) score at 3 months and symptomatic intracranial hemorrhages (SICH) between patients treated with drip-and-ship paradigm and those treated via direct visit. Results: Among 1,843 patients who met the eligible criteria, 244 patients (13.2%; 95% CI, 11.7-14.9) were treated using drip-and-ship paradigm. Patients treated with drip-and-ship paradigm had shorter onset to needle time compared with patients treated via direct visit (median[IQR], 110 minutes[79-150] vs 126 minutes[90-173], p&lt;0.001). After multivariable analysis, patients treated with drip-and-ship paradigm had significantly greater risk of unfavorable functional outcome (mRS 2-6) at 3 months after the stroke compared with patients treated via direct visit (OR 2.15; 95% CI, 1.50-3.08; p &lt; 0.001). SICH also occurred more frequently in patients treated with drip-and-ship paradigm (OR 1.78; 95% CI, 1.02-3.12; p =0.04). Of 1,843 patients, 509 patients (27.6%, 71 patients with drip-and-ship paradigm and 438 patients via direct visit) received subsequent endovascular recanalization therapy. The use of drip-and-ship paradigm caused approximately 105 minute delay in onset to groin puncture time compared with those treated via direct visit (305 minutes[260-345] vs 200 minutes[155-245], p&lt;0.001). Conclusions: Drip-and-ship thrombolysis paradigm was used in less than 15% of patients treated with tPA, and use of the paradigm caused a significant delay in onset to groin puncture time for endovascular therapy.

Update of the Korean Clinical Practice Guidelines for Endovascular Recanalization Therapy in Patients with Acute Ischemic Stroke.

Patients with severe stroke due to acute large cerebral artery occlusion are likely to be severely disabled or dead without timely reperfusion. Previously, intravenous tissue plasminogen activator (IV-TPA) within 4.5 hours after stroke onset was the only proven therapy, but IV-TPA alone does not sufficiently improve the outcome of patients with acute large artery occlusion. With the introduction of the advanced endovascular therapy, which enables more fast and more successful recanalization, recent randomized trials consecutively and consistently demonstrated the benefit of endovascular recanalization therapy (ERT) when added to IV-TPA. Accordingly, to update the recommendations, we assembled members of the writing committee appointed by the Korean Stroke Society, the Korean Society of Interventional Neuroradiology, and the Society of Korean Endovascular Neurosurgeons. Reviewing the evidences that have been accumulated, the writing members revised recommendations, for which formal consensus was achieved by convening a panel composed of 34 experts from the participating academic societies. The current guideline provides the evidence-based recommendations for ERT in patients with acute large cerebral artery occlusion regarding patient selection, treatment modalities, neuroimaging evaluation, and system organization.