Modeling diffusion-weighted imaging lesion expansion between 2 and 24 h after endovascular thrombectomy in acute ischemic stroke.

PURPOSE: Diffusion-weighted imaging (DWI) lesion expansion after endovascular thrombectomy (EVT) is not well characterized. We used serial diffusion-weighted magnetic resonance imaging (MRI) to measure lesion expansion between 2 and 24 h after EVT. METHODS: In this single-center observational analysis of patients with acute ischemic stroke due to large vessel occlusion, DWI was performed post-EVT (< 2 h after closure) and 24-h later. DWI lesion expansion was evaluated using multivariate generalized linear mixed modeling with various clinical moderators. RESULTS: We included 151 patients, of which 133 (88%) had DWI lesion expansion, defined as a positive change in lesion volume between 2 and 24 h. In an unadjusted analysis, median baseline DWI lesion volume immediately post-EVT was 15.0 mL (IQR: 6.6-36.8) and median DWI lesion volume 24 h post-EVT was 20.8 mL (IQR: 9.4-66.6), representing a median change of 6.1 mL (IQR: 1.5-17.7), or a 39% increase. There were no significant associations among univariable models of lesion expansion. Adjusted models of DWI lesion expansion demonstrated that relative lesion expansion (defined as final/initial DWI lesion volume) was consistent across eTICI scores (0-2a, 0.52%; 2b, 0.49%; 2c-3, 0.42%, p = 0.69). For every 1 mL increase in lesion volume, there was 2% odds of an increase in 90-day mRS (OR: 1.021, 95%CI [1.009, 1.034], p < 0.001). CONCLUSION: We observed substantial lesion expansion post-EVT whereby relative lesion expansion was consistent across eTICI categories, and greater absolute lesion expansion was associated with worse clinical outcome. Our findings suggest that alternate endpoints for cerebroprotectant trials may be feasible.

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

BACKGROUND: While 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. METHODS: Consecutive 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. RESULTS: 483 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. CONCLUSION: The 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.

Optimal Angiographic Goal and Number of Passes for Octogenarians Undergoing Endovascular Stroke Thrombectomy.

BACKGROUND: The optimal recanalization goal and number of endovascular thrombectomy (EVT) passes for elderly patients with large vessel occlusion strokes is unclear. METHODS: Consecutive patients 80 years or older undergoing EVT were identified from 2016 to 2022 at a single center. Clinical information, procedural details, and modified treatment in cerebral ischemia (mTICI) scores were collected. Primary outcome was modified Rankin scale (mRS) at 90 days. Bivariate and multivariable analyses were conducted to assess associations between mTICI scores, EVT passes, and 90-day outcomes. RESULTS: One hundred twenty-six patients were identified. At 90 days, mTICI 2b recanalization resulted in high rates of poor outcomes (8.7% functional independence and 60.9% mortality) not significantly different from mTICI 0, 1 or 2a (median mRS 6 vs. 6, P = 0.61). Complete recanalization (mTICI 2c or 3) led to significantly better mRS outcomes at 90 days compared to mTICI 2b (median mRS 4 vs. 6, adjusted P = 0.038), with 26.8% functional independence and 37.8% mortality. In multivariable analysis, complete recanalization was significantly associated with better 90-day outcomes than mTICI 2b or lower recanalization (odds ratio 4.24 [95% Confidence interval 1.46-12.3]; P = 0.002), while the number of passes was not independently associated with worse outcomes (P = 0.98). CONCLUSIONS: For octogenarians, mTICI 2b recanalization yields limited clinical benefit and results in poor 90-day outcomes. In contrast, complete recanalization is independently associated with significantly better outcomes. Thus, once the decision is made to pursue EVT in the elderly, mTICI 2c or better recanalization should be the angiographic goal. Providers should not withhold thrombectomy passes based on age alone.

Role of the Critical Care Resuscitation Unit in a Comprehensive Stroke Center: Operations for Mechanical Thrombectomy During the Pandemic.

Introduction: Standard of care for patients with acute ischemic stroke from large vessel occlusion (AIS-LVO) includes prompt evaluation for urgent mechanical thrombectomy (MT) at a comprehensive stroke center (CSC). During the start of the coronavirus 2019 pandemic (COVID-19), there were reports about disruption to emergency department (ED) operations and delays in management of patients with AIS-LVO. In this study we investigate the outcome and operations for patients who were transferred from different EDs to an academic CSC's critical care resuscitation unit (CCRU), which specializes in expeditious transfer of time-sensitive disease. Methods: This was a pre-post retrospective study using prospectively collected clinical data from our CSC's stroke registry. Adult patients who were transferred from any ED to the CCRU and underwent MT were eligible. We compared time intervals in the pre-pandemic (PP) period between January 2018- February 2020, such as ED in-out and CCRU arrival-angiography, to those during the pandemic (DP) between March 2020-May 31, 2021. We used classification and regression tree (CART) analysis to identify which time intervals, besides clinical factors, were associated with good neurological outcome (90-day modified Rankin scale 0-2). Results: We analyzed 203 patients: 135 (66.5%) in the PP group and 68 (33.5%) in the DP group. Time from ED triage to computed tomography (difference 7 minutes, 95% confidence interval [CI] -12 to -1, P < 0.01) for the DP group was statistically longer, but ED in-out was similar for both groups. Time from CCRU arrival to angiography (difference 9 minutes, 95% CI 4-13, P < 0.01) for the DP group was shorter. Forty-nine percent of the DP group achieved mRS ≤ 2 vs 32% for the PP group (difference -17%, 95% CI -0.32 to -0.03, P < 0.01). The CART identified initial National Institutes of Health Stroke Scale, age, ED in-and-out time, and CCRU arrival-to-angiography time as important predictors of good outcome. Conclusion: Overall, the care process in EDs and at this single CSC for patients requiring MT were not heavily affected by the pandemic, as certain time metrics during the pandemic were statistically shorter than pre-pandemic intervals. Time intervals such as ED in-and-out and CCRU arrival-to-angiography were important factors in achieving good neurologic outcomes. Further study is necessary to confirm our observation and improve operational efficiency in the future.

Infarcts Due to Large Vessel Occlusions Continue to Grow Despite Near-Complete Reperfusion After Endovascular Treatment.

BACKGROUND AND PURPOSE: Infarcts in acute ischemic stroke (AIS) patients may continue to grow even after reperfusion, due to mechanisms such as microvascular obstruction and reperfusion injury. We investigated whether and how much infarcts grow in AIS patients after near-complete (expanded Thrombolysis in Cerebral Infarction [eTICI] 2c/3) reperfusion following endovascular treatment (EVT), and to assess the association of post-reperfusion infarct growth with clinical outcomes. METHODS: Data are from a single-center retrospective observational cohort study that included AIS patients undergoing EVT with near-complete reperfusion who received diffusion-weighted magnetic resonance imaging (MRI) within 2 hours post-EVT and 24 hours after EVT. Association of infarct growth between 2 and 24 hours post-EVT and 24-hour National Institutes of Health Stroke Scale (NIHSS) as well as 90-day modified Rankin Scale score was assessed using multivariable logistic regression. RESULTS: Ninety-four of 155 (60.6%) patients achieved eTICI 2c/3 and were included in the analysis. Eighty of these 94 (85.1%) patients showed infarct growth between 2 and 24 hours post-reperfusion. Infarct growth ≥5 mL was seen in 39/94 (41.5%) patients, and infarct growth ≥10 mL was seen in 20/94 (21.3%) patients. Median infarct growth between 2 and 24 hours post-reperfusion was 4.5 mL (interquartile range: 0.4-9.2 mL). Post-reperfusion infarct growth was associated with the 24-hour NIHSS in multivariable analysis (odds ratio: 1.16 [95% confidence interval 1.09-1.24], P<0.01). CONCLUSION: Infarcts continue to grow after EVT, even if near-complete reperfusion is achieved. Investigating the underlying mechanisms may inform future therapeutic approaches for mitigating the process and help improve patient outcome.

Factors Affecting Selection of TraineE for Neurointervention (FASTEN).

BACKGROUND AND IMPORTANCE: Neurointervention is a very competitive specialty in the United States due to the limited number of training spots and the larger pool of applicants. The training standards are continuously updated to ensure solid training experiences. Factors affecting candidate(s) selection have not been fully established yet. Our study aims to investigate the factors influencing the selection process. METHODS: A 52-question survey was distributed to 93 program directors (PDs). The survey consisted of six categories: (a) Program characteristics, (b) Candidate demographics, (c) Educational credentials, (d) Personal traits, (e) Research and extracurricular activities, and (f) Overall final set of characteristics. The response rate was 59.1%. As per the programs' characteristics, neurosurgery was the most involved specialty in running the training programs (69%). Regarding demographics, the need for visa sponsorship held the greatest prominence with a mean score of 5.9 [standard deviation (SD) 2.9]. For the educational credentials, being a graduate from a neurosurgical residency and the institution where the candidate's residency training is/was scored the highest [5.4 (SD = 2.9), 5.4 (SD = 2.5), respectively]. Regarding the personal traits, assessment by faculty members achieved the highest score [8.9 (SD = 1)]. In terms of research/extracurricular activities, fluency in English had the highest score [7.2 (SD = 1.9)] followed by peer-reviewed/PubMed-indexed publications [6.4 (SD = 2.2)]. CONCLUSION: Our survey investigated the factors influencing the final decision when choosing the future neurointerventional trainee, including demographic, educational, research, and extracurricular activities, which might serve as valuable guidance for both applicants and programs to refine the selection process.