Thrombectomy For Stroke Research Articles

Abstract TP195: Impact of Intracranial Atherosclerotic Disease on Thrombectomy Outcomes in Acute Cerebral Infarction With Large Vessel Occlusion

Introduction: In acute cerebral infarction with Large Vessel Occlusion (LVO), Intracranial Atherosclerotic Disease (ICAD) often causes vascular occlusion. Previous studies have noted that ICAD-related LVOs, compared to embolic occlusions, have longer procedural times and lower successful reperfusion rates. However, clinical outcomes remain similar. This study compares post-thrombectomy outcomes in both groups, matched by initial NIHSS scores. Method: From October 2017 to March 2023, we studied LVO cases undergoing thrombectomy for acute ischemic stroke. Our primary focus was on evaluating thrombectomy outcomes within two distinct groups— ICAD-related LVO group (ICAD group) and Embolic LVO group (Embolic group)—matched based on preoperative NIHSS scores. ICAD group was defined as persistent occlusion or residual stenosis at the initial occlusion site. Patient outcomes at 3 months were assessed using modified Rankin Scale (mRS) scores, defining devastating outcomes as mRS 5-6. Successful recanalization was defined as Thrombolysis in Cerebral Ischemia score ≥2b. Logistic regression identified factors independently associated with devastating outcomes. Result: Analyzing 2407 cases, we extracted matched pairs (33 each) adjusted by NIHSS. ICAD group had lower atrial fibrillation frequency, lower BNP levels, more M1 occlusions, and fewer M2 occlusions compared to the Embolic group. In treatment outcomes, ICAD group had lower successful recanalization (82% vs 43%, P =0.001), higher reocclusion rates (0% vs 21%, P =0.005), and longer puncture-to-reperfusion time (median 51 vs 88 minutes, P <0.001). Devastating outcomes were higher in ICAD group (15% vs 39%, P =0.027). Multivariate analysis showed ICAD's independent association with devastating outcomes (Odds ratio, 6.54; 95% CI, 1.56-27.4; P =0.010) along with age, NIHSS, and tPA absence. Conclusion: In thrombectomy-treated LVO patients, matching based on admission NIHSS scores revealed significantly higher devastating outcomes in the ICAD group when compared to the Embolic group.

Abstract 158: Rescue Strategy for Failed Mechanical Thrombectomy in Acute Ischemic Stroke: An Analysis of the SVIN Registry

Background: Mechanical thrombectomy (MT) fails to achieve successful reperfusion in up to 20% of large vessel occlusions (LVOs). Rescue strategies (RS) have shown promise in multicenter studies and meta-analyses. We aimed to evaluate the association between RS with functional outcomes compared to medical management (MM) in patients who underwent failed MT. Methods: This is a cross-sectional study using prospectively collected data from the Society of Vascular and Interventional Neurology (SVIN) Registry from 2018 to 2021. We included all adult patients with anterior circulation LVOs who experienced a failed MT (mTICI 0-2a after multiple attempts to clot retrieval) at the 14 participating centers. The patients were divided into two groups: those who received RS (including balloon angioplasty alone, intracranial stenting with or without balloon angioplasty) and those who only received MM. The primary outcome was the shift in the degree of disability, as measured by the mRS at 90 days. Additional outcomes included functional independence (90-day mRS score of 0-2), sICH, and mortality at 90 days. Results: A total of 642 patients were included in the analysis. The RS group consisted of 294 (45.8%) patients, while the MM group comprised 348 (54.2%) patients. A mTICI score of 2b-3 was achieved in 242/293 (82.6%) patients in the RS group. After adjusting for confounders, the RS group showed a favorable shift in the overall 90-day mRS distribution (acOR=1.97, 95%CI 1.36-2.85, p =<0.001) and higher rates of functional independence (RS: 30.7% vs. MM: 12%, aOR=2.39, 95%CI 1.34-4.26, p =0.003) ( Figure ) compared to the MM group. RS also showed lower rates of sICH (RS: 2.7% vs. MM: 9%, aOR=0.32, 95%CI 0.14-0.71, p =0.005) and 90-day mortality (RS: 29.5% vs. MM: 49.7%, aOR=0.49, 95%CI 0.33-0.74, p =<0.001). Conclusion: Our findings support the use of RS as a potential alternative for stroke patients with failed MT. Further prospective studies are needed to validate these observations.

Abstract WP124: Dual Energy Head CT Immediately Following Mechanical Thrombectomy Rarely Leads to Changes in Clinical Management

Introduction: No guidelines exist regarding imaging after mechanical thrombectomy (MT) for acute ischemic stroke (AIS). Dual Energy Head CT (DECT) can differentiate between contrast staining and intracranial hemorrhage (ICH). We obtained routine DECT for AIS patients immediately following MT. We aimed to understand the impact of DECT on clinical management. Methods: We conducted a single-center retrospective study of AIS patients who underwent MT and immediate post-procedure DECT between March 2021 and February 2023. Patients were grouped by whether or not DECT results changed management, compared to our standard post-thrombectomy protocol and as documented in clinical notes. Continuous variables were compared using Wilcoxon Rank-Sum tests, and categorical variables were compared using Chi-square tests. Results: Of 173 patients who met inclusion criteria, 13 (7.5%) had documented changes in management following DECT. Management changes included delayed anti-thrombotic administration, lowered systolic blood pressure goals, and serial imaging. There were no statistically significant differences in age, gender, initial NIHSS, ischemic core size pre-MT, or treated vessel between patients with and without a change in management. Patients with management changes were more likely to have had procedural complications, contrast staining, any ICH, and symptomatic ICH (Table). While 34 patients had ICH on DECT, this only led to a documented change in management for 11 (32.4%) patients. Conclusion: Routine DECT immediately after MT rarely changed clinical management. Immediate DECT may be reserved for patients with intraprocedural complications or those with clinical suspicion of ICH.

Long-term results of mechanical thrombectomy for large ischaemic stroke

Long-term results of mechanical thrombectomy for large ischaemic stroke

Abstract 152: Endovascular Therapy versus Medical Management for Acute Ischemic Stroke With Large Infarct: A Time-Benefit Relationship Analysis

Objective: Recent randomized trials demonstrated the benefit of endovascular thrombectomy for acute ischemic stroke with large infarct. We aimed to characterize the effect of time to treatment on the benefit of endovascular therapy compared to medical management among patients with acute large ischemic stroke. Methods: Analysis the Endovascular Therapy in Acute Anterior Circulation Large Vessel Occlusive Patients with a Large Infarct Core trial (ANGEL-ASPECT), which was a multicenter, randomized trial at 46 comprehensive stroke centers in China from August 2020 to October 2022. Onset to arterial puncture time (OPT) associated with outcomes of endovascular therapy were analyzed as a category and continuous variable. The primary outcome was favorable outcome (modified Rankin scale 0-3) at 90 days. Secondary outcomes included degree of disability (modified Rankin scale range), symptomatic intracranial hemorrhage, any intracranial hemorrhage, and mortality. Results: Among 455 eligible patients, the median age was 68 years, and median Alberta Stroke Program Early Computed Tomography Score was 3 (interquartile range 3-4). Compared with medical management alone, endovascular therapy plus medical management was associated with higher rates of favorable outcome with OPT within 6 hours (44.4% vs 29.9%, adjusted odds ratio[aOR] 2.78 [95% confidence interval [CI] 1.22-6.32]), 6-12 hours (45.7% vs 29.6%, aOR 2.39 [95% CI 1.21-4.71]), but not in OPT beyond 12 hours (51.6% vs 41.4%, aOR 2.05 [95% CI, 0.88-4.77]). The benefit in favorable outcome became nonsignificant after OPT of 13 hours and 22 minutes. In three OPT intervals, the odds of better disability outcome with endovascular therapy plus medical management than medical management alone were observed; the rates of symptomatic intracranial hemorrhage and mortality were similar, though the rates of any intracranial hemorrhage increased. Conclusion: In patients with large cerebral infarction, endovascular therapy plus medical management was efficacious in improving functional outcomes with acceptable safety in a broad time window of 0 to 24 hours, but greater benefit was observed with earlier treatment. A pooled analysis with larger sample size is needed.

Abstract TP188: Diving MCA and First-Pass Reperfusion: A Subgroup Analysis of the Arise II Study

Introduction: Tortuosity of Internal carotid artery impact on achieving first pass in mechanical thrombectomy has been previously described. Here, we investigate the association of middle cerebral artery(MCA) tortuosity on radiographic and functional outcome. Methods: The Analysis of Revascularization in Ischemic Stroke with EmboTrap II was utilized to identify patients with anterior circulation stroke. MCA tortuosity was calculated using Inflection Count Metric(ICM) by two blinded readers to angiographical/clinical outcomes. The total cohort was trichotomized into 3 groups (A, B, C) based on M1 tortuosity tertiles. The primary efficacy end point was achievement of modified Thrombolysis in Cerebral Ischemia (mTICI) reperfusion scores of ≥2b on first pass. Good functional outcomes was defined as mRS0-2 on 90-day followup. Baseline and procedural data were compared between groups. Results: A total of 200 with known MCA tortuosity were identified. Patients within group A were significantly older (P<0.05) . Group C patient were more likely to have renal disease and atrial fibrillation (P<0.05). There was no differences in terms of NIHSS score at presentation nor ASPECT score between groups. Achieving first-pass success was more likely in group A (60.6%) vs 47% and 38.2%, P=0.033 for groups B and C, respectively. Likewise, the rate of mTICI≥2c was higher in group A (54.5%) vs 36.4% and 26.5%, p=0.003. Achieving mRS0-2 was more likely in group A (76.6%) vs 73.4% and 49.3%, p=0.001. There were no differences in distal emboli, or symptomatic intracranial hemorrhage. Findings of first-pass and angiographic outcomes were consistent with standard tortuosity scoring system. Conclusion: Patients with higher MCA tortuosity are less likely to have successful reperfusion and good functional outcome post mechanical thrombectomy for acute ischemic stroke.

Abstract WP133: Phase MRI Clot Characteristic and Radiologic Thrombectomy Outcomes in Acute Ischemic Stroke

Background: Magnetic Resonance (MR) susceptibility weighted imaging (SWI) sequences produce filtered Phase images where blood products demonstrate signal intensities opposite to calcifications. Though susceptibility Vessel Sign (SVS) on pre-interventional MRI has been reported as an indicator of outcome following thrombectomy, the association of Phase MR imaging with thrombectomy outcomes is not previously studied. Methods: In this retrospective cohort study of consecutive acute large vessel occlusion strokes with Phase MR imaging prior to thrombectomy, we evaluated the correlation between clot features on pre-interventional MR imaging with radiographic outcomes following thrombectomy. The clot characteristics included the presence of SVS and its geometrical features on both Phase and GRE sequenced MRIs and thrombus extension. Results: A total of 57 patients were included in this analysis (mean age: 65.04 ± 15.8, 33% Female, mean NIHSS: 13.0 (7.5, 19.5), 33% M1 occlusion), among which 52 (91%) patients had positive SVS on phase-sequence MRI. Successful recanalization was achieved in 91% and successful first pass recanalization was observed in 46%. In univariate analysis, baseline demographics and clinical characteristics including age, sex, and comorbidities were not associated with successful recanalization. Homogeneity of Phase-SVS was significantly associated with the first pass successful recanalization (Odds ratio (OR) 1.81; Confidence interval (CI) [1.14-2.88], p: 0.006). Conclusion: Our study suggests MRI Phase-SVS clot homogeneity as a novel predictor of first pass successful recanalization following mechanical thrombectomy in acute stroke.

Abstract WMP46: Rurality Affects Access to Mechanical Thrombectomy for Large Vessel Occlusion Stroke on a Global Scale

Introduction: Global mechanical thrombectomy access (MTA) for large vessel occlusion (LVO) stroke is extremely low. Rural patients are less likely to receive initial care at a thrombectomy-capable hospital. While regional studies have suggested rurality as a barrier to MTA, the magnitude and variability of this effect across countries is unknown. The aim of this study is to evaluate the association of country-level % of the rural population with access to mechanical thrombectomy. Methods: We conducted an online survey of 75 countries through the Mission Thrombectomy 2020+ (MT2020+) global professional peer network between November 22, 2020, and February 28, 2021. Questions included country-level availability of MT centers, operators, procedures, reimbursement, emergency medical services, cultural barriers, and other factors affecting systems of stroke care. MTA was defined as the estimated proportion of patients with thrombectomy-eligible LVOs receiving MT in each region annually. We used the World Bank data to obtain the income class based on per capita GNI of a country and the proportion of rural population expressed as % of total population of each country. In the final analysis, 60 countries were included. We used multivariable-adjusted generalized linear models with logit link to evaluate the association of rural population % with MT access. Results: The median country-level % of rural population among 60 countries was 30.5% (IQR 16.1-45.7%). In univariable generalized linear models, each 5% increase in country-level % of rural population was associated with 22% lower odds of MT access (OR 0.78, 95%CI 0.70-0.86, p<0.001). After adjustment for differences in country-level % of GDP spent on healthcare, reimbursement for MT, country’s income class, prehospital emergency services (EMS) system availability, training, and triage systems, each 5% increase in % of rural population was associated with 6% lower odds of MT access (OR 0.94, 95%CI 0.90-0.99, p=0.013). Conclusion: The % of rural population of countries is a significant independent negative predictor of access to mechanical thrombectomy. The % of rural populations and its distribution within countries needs to be carefully studied, as policies to improve access are created and implemented.

Abstract WP153: Factors Affecting Length of ICU Stay After Endovascular Thrombectomy for Acute Large Vessel Ischemic Stroke

Introduction: The advent of endovascular thrombectomy (EVT) for acute large vessel occlusion (LVO) ischemic stroke has reduced the overall ICU length of stay (LoS), especially for patients undergoing successful reperfusion. Prolonged ICU LoS is reported to be associated with worse clinical outcomes, but factors associated with prolonged LoS after MT are not established. Methods: A retrospective analysis of 499 patients undergoing EVT at a single large comprehensive stroke center from January 2015 to May 2020 was performed. Demographics, procedure variables, ICU LoS, ICU complications, and modified Rankin scale at discharge were collected. Multiple regression was used to identify independent variables affecting the ICU LoS. Additional analysis using t-test assuming unequal variances was performed for select variables. Results: The median age was 72 [61-82], 254 (51%) male & median NIHSS was 16 [10-20]. The average door-to-puncture time was 104 ±28 mins and the average procedure time 43.9 ±28.7. General anesthesia (GA) was administered in 257 (51%) patients. Successful reperfusion (TICI 2c-3) was achieved in 334 (67%) patients. Median ICU LoS was 3 days [1-5]. Patients with mRS 0-2 at discharge (33%) had shorter ICU LoS (2.8 vs 5.7, P<0.001). ASPECTS < 7 (6.9 vs 4.6, P=0.03), use of GA (6.2 vs 3.3 days, P<0.001) and ICU complications such as pulmonary embolism (PE) and pneumonia (10 vs 4 days; p <0.001) significantly increased the ICU LoS. Successful reperfusion significantly reduced ICU LoS (4.2 vs 5.8 days, p=0.015). After adjusting for age, sex, baseline NIHSS and ASPECTS, both the procedure time (b= 0.03, P=0.02) and final TICI score (b= -0.76, P=0.001) were independently associated with prolonged ICU LoS (R2=0.1, F=4, P<0.001). Conclusion: Pre-procedural factors such as poor ASPECTS (< 7), procedural factors such as the use of GA, prolonged procedure time, and TICI 0-2b reperfusion, and ICU complications such as pneumonia and PE are associated with prolonged ICU LoS.

Abstract WMP50: Disparities of Interhospital Transfer for Mechanical Thrombectomy in Acute Stroke in US

Introduction: A large proportion of mechanical thrombectomies (MT) in acute stroke include patients transferred from an outside hospital to thrombectomy capable centers. However, patient characteristics associated with the odds of transfer is unknown. We explored the US national claims database to explore predictors of interfacility transfer in MT hospitalizations using a nationally representative sample. Methods: National Inpatient Sample database was retrospectively explored from 2016 to 2020 for stroke hospitalizations with EVT. The primary outcome was transfer status from the presenting emergency department of MT-capable hospital. Multivariable logistic regression models with multiple robustness checks were performed to determine patient characteristics with the odds of transfer. Results: This study included 100,865 patients with MT, of whom 32,685 patients (32.4%) were transferred (median [IQR] age, 71 [60-81] years; 16775 women [51.2%]; 23090 White individuals [74.9%]; 3715 Black individuals [12.1%]; 1875 Hispanic individuals [6.1%]; 895 Asian individuals [2.9%]). White race, higher baseline NIHSS, hospital size and status (urban teaching vs rural), and hospital location were independent predictors of interfacility transfer for MT. Conclusion: Nearly one in 3 MTs in the US is performed in patients presenting following transfer from another acute care hospital. Analysis of population level data utilizing the National Inpatient Sample database shows disparities in the transfer of patients with minority backgrounds (Black, Hispanic, Asian) for MT. Urban teaching centers, larger hospitals, higher baseline NIHSS, and hospital location (northeast and midwest) were more likely to receive Interhospital MT transfers regardless of race.

Abstract TP205: Intracranial Stenting With Mechanical Thrombectomy in Acute Ischemic Stroke in the United States

Background and Purpose: Large vessel occlusion secondary to intracranial atherosclerotic disease (ICAD-LVO) has an estimated prevalence of 10-30%. Registry-based reports from high volume centers indicate that about 4-7% of mechanical thrombectomy (MT) due to LVO are accompanied with intracranial rescue stenting in the US, yet the trend and utilization of rescue stenting in US is unknown. Methods: Analysis of US National Inpatient Sample of strokes with mechanical thrombectomy with or without concomitant intracranial stenting from October 1st, 2016, to December 31st, 2020, was performed. Patient- and hospital-level characteristics were analyzed. Outcomes included favorable disposition (discharged to home) and in-hospital mortality. Results: Among 68,975 of stroke MT with recorded NIHSS during the study period (51.1% women; mean age, 69.1 [SD, 14.6] years; mean NIHSS score of 15.1 [SD, 7.7]), 1,635 (2.3%) underwent concomitant intracranial stenting (44% women; mean age, 64.8 [SD, 13.7] years; mean NIHSS score of 13.8 [SD, 8.1]). Characteristics associated with intracranial stent utilization were male sex, history of diabetes, hypertension, or chronic kidney disease, absence of atrial fibrillation or CHF, and southern US region. Favorable outcome was achieved in 23.6% of MT with stenting versus 32.3% without stenting (P<0.001). In-hospital mortality occurred in 17.1% of MTs with stenting versus 10.5% without stenting (P<0.001). In multivariable analysis among MTs with concomitant intracranial stenting, favorable outcome was associated with lower presenting NIHSS (OR, 0.91 [95% CI, 0.87-0.95], P<0.001), and absence of DM (OR, 0.41 [95% CI, 0.20-0.85], P<0.01). In-hospital mortality was associated with male sex (OR, 3.08 [95% CI, 1.38-6.87], P=0.005) and concomitant IV lytic administration (OR, 2.45 [95% CI, 1.01-5.96], P=0.02). Conclusions: In US practice, less than 3/100 MT’s are performed with concomitant intracranial stenting which is well below the prevalence of failed thrombectomy rates due to underlying ICAD-LVO. Further studies are needed to improve outcomes in this subset of patients.

Abstract TP196: Ischemic Stroke With Large Vessel Occlusion and Systemic Acidosis: Associations With Functional Outcomes and Mortality

Introduction: Systemic acidosis is common in critical conditions, including severe myocardial infarction, renal and liver injuries, and traumatic brain injury. However, the potential connection between ischemic stroke involving large vessel occlusion (LVO) and acidosis has not been extensively explored. With this study we aimed to assess the prevalence of respiratory and metabolic acidosis in ischemic stroke with LVO and their potential links to functional outcomes and mortality. Methods: Retrospective single center cohort of patients with ischemic stroke and LVO status post endovascular thrombectomy. Univariate logistic regression was used to examine the relationship between acidosis on admission and (1) hospital mortality and (2) 90-day modified Rankin Scale (mRS) dichotomized as unfavorable (>3) vs favorable (≤3). In addition, we investigated association with acidosis and symptomatic ICH. Metabolic acidosis was defined by the presence of one of the following: Serum bicarbonate <22 mEq/L, lactic acid >2 mmol/L or pH <7.35. Respiratory acidosis was defined by pCO2 >45 mmHg. Results: There was a total of 346 patients, average age was 68.5 (±15) years, 169 (49%) were females. 168 (49%) patients were acidotic on admission, 4 (1%) had respiratory acidosis, 7 (2%) had mixed acidosis and the remaining 157 (45%) had metabolic acidosis. There was no statistically significant association between systemic acidosis with either hospital mortality (p=0.31]) or 90-day favorable functional outcome (p=0.23]). There was no association between acidosis with symptomatic ICH (p=0.47). Conclusion: In our retrospective cohort study, we observed that approximately half of the patients with stroke and LVO had systemic acidosis. Unlike other critical neurological conditions like traumatic brain injury, we did not identify a substantial correlation between systemic acidosis and either mortality or the functional outcome at the 90-day mark. Given the high prevalence of acidosis in patients with LVO, larger multi-center studies are needed to further investigate its association with the outcomes and mortality.

Abstract TP172: Rising Trends in Cervical Artery Dissection Admissions: A Nationwide Study From 2005 to 2019

Introduction: A recent regional study suggested an upward trend in the incidence rates of spontaneous cervical artery dissection (sCAD). Utilizing a comprehensive nationwide database, we investigated these trends on a national scale. Method: We analyzed adult patients diagnosed with sCAD in the United States National Inpatient Sample database from 2005 to 2019, employing validated standard ICD-9 and ICD-10 diagnostic codes. By integrating the survey-weighted annual total of CAD cases with annual Census data, we estimated the incidence over the study period. The annualized percentage change (APC) over the study period was estimated using regression models and visually represented with an exponential regression line. Trends were further stratified by sex, age group, and race. Result: From 2005 to 2019, we identified 557,063,391 patients, of whom 125,102 (0.02%) had non-traumatic CAD. The incidence of CAD increased from 10.5 cases per million population in 2005 to 45.5 cases per million population in 2019 ( P < 0.001), revealing a significant increase in admissions with CAD. Regression analysis estimated an APC of 9.6%, with a 95% CI of 8.4% to 10.7% (P < 0.001) (Figure). This upward trend persisted across all strata of sex, age, and race. Conclusion: Our nationwide analysis demonstrates a significant rise in admissions with CAD from 2005 to 2019 across all demographic groups. The change in trend could be attributed to greater disease awareness leading to more frequent coding of CAD diagnoses, and/or to increased use of CT angiogram coinciding with the rise of mechanical thrombectomy for stroke. This underscores CAD's increasing clinical prevalence, warranting further investigation into its causes, prevention, and treatment.

Review and prospects of international clinical research in critical care medicine in 2023

The main clinical research advances of critical care in 2023 includes: new trials of Chinese herbal medicine, hydroxocobalamin (vitamin B12), methylene blue as well glucocorticoids have shown the potential to improve outcomes of patients with sepsis and septic shock; international committees launched new global definition and managing recommendations for acute respiratory distress syndrome (ARDS). Besides, a cluster of new evidences has emerged in many aspects as following: fluid control strategy in sepsis (restrictive/liberative), antibiotic infusion strategy (continuous/intermittent), oxygen-saturation targets for mechanical ventilation (conservative/liberative), blood pressure targets after resuscitation from out-of-hospital cardiac arrest (hypotension/hypertension), blood pressure targets after successful stroke thrombectomy (intensive/conventional), and nutritional support strategies (low protein-calories/conventional protein-calories, fasting/persistent feeding before extubation). Thus, given above progress, carrying out high -quality domestic multi-center clinical registration researches, constructing shareable standardized databases, as well raising public awareness of sepsis, should be the essential steps to improve our level of intensive care medicine.

Abstract WP191: Impact and Determinants of Door In-Door Out Time for Stroke Thrombectomy Transfers: Real World Analysis of a Large Hub-and-Spoke Network

Introduction: The mantra ‘time is brain’ cannot be overstated for patients suffering from acute ischemic stroke. This is especially true for those with large vessel occlusions (LVO) requiring transfer to an endovascular thrombectomy (EVT) capable center. We sought to evaluate the spoke hospital door in-door out (DIDO) times for patients transferred to our hub center for EVT. Methods: Individuals who first presented with LVO to a spoke hospital and were then transferred to the hub for EVT were retrospectively identified from a prospectively maintained database from January 2019 to November 2022. DIDO was defined as the time between spoke hospital door in arrival and door out exit. Baseline characteristics, treatments, and outcomes were compared, dichotomizing DIDO at 90 min based in the American Heart Association goal for DIDO ≤90 min for 50% of transfers. Multivariable regression analyses were performed for determinants of 90-day ordinal modified Ranking Scale (mRS) and DIDO. Results: We identified 194 patients transferred for EVT with available DIDO. The median age was 67 (IQR 57-80), and 46% were female. The median NIHSS was 16 (10-20), 50% were treated with intravenous thrombolysis at a spoke, and TICI 2B-3 reperfusion was achieved in 87% at the hub. The median DIDO was 120 min (97-149), with DIDO ≤90 min achieved in 18%. DIDO was a significant determinant of 90-day ordinal mRS (B=0.007, 95%CI=0.001-0.012, p=0.013), even when accounting for last known well-to-spoke door in, spoke door out-to-hub arrival, hub arrival-to-puncture, puncture-to-first pass, age, NIHSS, intravenous thrombolysis, TICI 2B-3, and symptomatic intracranial hemorrhage. Importantly, determinants of DIDO included Black race or Hispanic ethnicity (B=0.918, 95%CI=0.010-1.826, p=0.048), atrial fibrillation or heart failure (B=0.793, 95%CI=0.257-1.329, p=0.004), and basilar LVO location (B=2.528, 95%CI=1.154-3.901, p<0.001). Conclusion: In this real-world analysis of a large hub-and-spoke network, spoke DIDO was the most important period of time for long term outcomes of LVO stroke patients treated with EVT. Determinants of DIDO were identified which require further investigation and motivate system changes that may reduce DIDO and improve patient outcomes.

No-reflow after stroke reperfusion therapy: An emerging phenomenon to be explored.

In the field of stroke thrombectomy, ineffective clinical and angiographic reperfusion after successful recanalization has drawn attention. Partial or complete microcirculatory reperfusion failure after the achievement of full patency of a former obstructed large vessel, known as the "no-reflow phenomenon" or "microvascular obstruction," was first reported in the 1960s and was later detected in both experimental models and patients with stroke. The no-reflow phenomenon (NRP) was reported to result from intraluminal occlusions formed by blood components and extraluminal constriction exerted by the surrounding structures of the vessel wall. More recently, an emerging number of clinical studies have estimated the prevalence of the NRP in stroke patients following reperfusion therapy, ranging from 3.3% to 63% depending on its evaluation methods or study population. Studies also demonstrated its detrimental effects on infarction progress and neurological outcomes. In this review, we discuss the research advances, underlying pathogenesis, diagnostic techniques, and management approaches concerning the no-reflow phenomenon in the stroke population to provide a comprehensive understanding of this phenomenon and offer references for future investigations.

Implementation of a Thrombectomy Stroke Center Triage Program in New York City Emergency Medical Services

Background Due to the increased morbidity and mortality associated with acute cerebral ischemia caused by large vessel occlusions, the New York City (NYC) 9‐1‐1 Emergency Medical Services system implemented the NYC Stroke Triage Protocol with the intention of improving access to endovascular therapy for patients with suspected severe stroke. Methods Successful collaboration between multiple stakeholders enabled the NYC region to develop and implement a new stroke system of care for patients treated by Emergency Medical Services. Descriptive statistics including medians (interquartile range) and proportions were used as appropriate. Continuous data were compared using Mann–Whitney tests for medians and categorical data were compared by using Pearson chi‐square test. Results Between April 1, 2019 and March 31, 2022, 1337 (83.5%) patients directly transported under the NYC Stroke Triage Protocol by the NYC 9‐1‐1 Emergency Medical Services system to a Thrombectomy Stroke Center had a stroke diagnosis. Patients transported to a more distant Thrombectomy Stroke Center traveled an average of 5.7 minutes longer compared with those who were delivered to the closest Primary Stroke Center but the overall time between first patient contact and first pass at a Thrombectomy Stroke Center was an estimated 98.2 minutes shorter. Approximately 24% of directly transported patients with a stroke diagnosis underwent a thrombectomy. Conclusions The NYC Stroke Triage Protocol increased access to advanced interventional stroke care for eligible patients by decreasing time to treatment through prehospital identification of patients with severe stroke and directly transporting them to a stroke center capable of providing endovascular therapy.

Thrombectomy in Stroke Patients With Low Alberta Stroke Program Early Computed Tomography Score: Is Modified Thrombolysis in Cerebral Infarction (mTICI) 2c/3 Superior to mTICI 2b?

Outcomes following mechanical thrombectomy (MT) are strongly correlated with successful recanalization, traditionally defined as modified Thrombolysis in Cerebral Infarction (mTICI) ≥2b. This retrospective cohort study aimed to compare the outcomes of patients with low Alberta Stroke Program Early Computed Tomography Score (ASPECTS; 2-5) who achieved mTICI 2b versus those who achieved mTICI 2c/3 after MT. This study utilized data from the Stroke Thrombectomy and Aneurysm Registry (STAR), which combined databases from 32 thrombectomy-capable stroke centers between 2013 and 2023. The study included only patients with low ASPECTS who achieved mTICI 2b, 2c, or 3 after MT for internal carotid artery or middle cerebral artery (M1) stroke. Of the 10,229 patients who underwent MT, 234 met the inclusion criteria. Of those, 98 (41.9%) achieved mTICI 2b, and 136 (58.1%) achieved mTICI 2c/3. There were no significant differences in baseline characteristics between the two groups. The 90-day favorable outcome (modified Rankin Scale score: 0-3) was significantly better in the mTICI 2c/3 group than in the mTICI 2b group (adjusted odds ratio 2.35; 95% confidence interval [CI] 1.18-4.81; P=0.02). Binomial logistic regression revealed that achieving mTICI 2c/3 was significantly associated with higher odds of a favorable 90-day outcome (odds ratio 2.14; 95% CI 1.07-4.41; P=0.04). In patients with low ASPECTS, achieving an mTICI 2c/3 score after MT is associated with a more favorable 90-day outcome. These findings suggest that mTICI 2c/3 is a better target for MT than mTICI 2b in patients with low ASPECTS.

Standard Versus Intensive Blood Pressure Control in Acute Ischemic Stroke Patients Successfully Treated With Endovascular Thrombectomy: A Systemic Review and Meta-Analysis of Randomized Controlled Trials.

The optimal blood pressure (BP) control after successful endovascular thrombectomy (EVT) in acute ischemic stroke (AIS) with large vessel occlusion (LVO) remains debatable. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) that evaluate the efficacy and safety of standard BP control (with systolic BP ≤180 mm Hg) versus intensive BP control (systolic BP <140 mm Hg) during the 24 hours after successful EVT in AIS with LVO. PubMed, Scopus, the Cochrane Central Register of Controlled Trials, and Embase were searched to identify relevant trials. The crude odds ratio (OR) and 95% confidence interval (CI) were calculated and estimates using random-effects models were pooled. This meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines (PROSPERO ID: CRD42023450673). Four RCTs involving 1,559 participants were included. Regarding efficacy outcomes, intensive BP control was associated with a lower likelihood of functional independence (OR: 0.68; 95% CI: 0.51-0.91 for modified Rankin Scale [mRS] ≤2) and walking without assistance (OR: 0.65; 95% CI: 0.53-0.81 for mRS ≤3). For safety outcomes, consistent with the efficacy findings, intensive BP control was significantly associated with severe disability or death (mRS 5 or 6) (OR: 1.34; 95% CI: 1.07-1.69). However, there were no significant differences including all-cause mortality, any intracerebral hemorrhage (ICH), symptomatic ICH, parenchymal hematoma type 2, and stroke recurrence. While all four RCTs were conducted to demonstrate the superiority of intensive BP control over standard BP control, standard BP control may be beneficial for the outcome after EVT for AIS with LVO without increasing adverse safety outcomes. Caution should be needed with the application of intensive BP control during the 24 hours following successful recanalization after EVT.

The BAND score: A simple model for upfront prediction of poor outcomes despite successful stroke thrombectomy

BackgroundWhile endovascular thrombectomy (EVT) is beneficial for patients with acute large vessel occlusion ischemic strokes, a significant portion of patients still do poorly despite successful recanalization. Identifying patients at high risk for poor outcomes can be helpful for future clinical trial design and optimizing acute stroke triage. MethodsConsecutive EVT patients were identified from 2016 to 2021 at a Comprehensive Stroke Center, and clinical information was recorded. Poor outcome was defined as a 90-day modified Rankin Scale (mRS) of 4 or greater despite achieving a modified thrombolysis in cerebral infarction (mTICI) score of 2b or greater. Multivariable regression analyses were used to identify risk factors for poor outcomes, and a scoring system was constructed. Results483 patients with successful recanalization were identified. From a randomly selected training cohort (n = 357), the 10-point BAND score was constructed from independent risk factors for poor outcomes: baseline disability (1 point: baseline mRS ≥ 2), age (1 point: 60–69 years, 2 points: 70–79 years, 3 points: 80–84 years, 4 points: 85 years or older), NIHSS (2 points: 13–17, 3 points: 18–22, and 4 points: ≥ 23), and delay from last known normal (1 point: ≥ 6 h). The BAND score was significantly associated with rates of poor outcomes (p < 0.001), and it achieved an area under the receiver-operating characteristic curve (AUC) of 0.80 (95 %CI 0.76–0.85) in our training cohort and 0.78 (95 %CI 0.70–0.86) in our validation cohort (n = 126). Overall, the BAND score had a significantly higher AUC value than the widely validated THRIVE score and the THRIVE-EVT calculation (p = 0.001 and 0.029, respectively). Among patients with high BAND scores (7 or higher), 88.2 % had poor outcomes. ConclusionThe BAND score is a simple tool to predict poor outcomes despite successful recanalization. Future studies are needed to confirm the BAND score's external validity.