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Background: High-grade intracranial atherosclerosis (ICAS) is associated with an elevated risk of recurrent ischemic stroke, particularly in patients with severe stenosis (70–99%). Identifying predictors of early recurrence can inform risk stratification and guide treatment strategies. Methods: The Biomarkers and Recurrence Risk in Symptomatic Intracranial Arterial Stenosis (BIORISK-ICAS) study is a multicenter, international, retrospective cohort analysis pooling data from 35 comprehensive stroke centers. We included hospitalized adult patients with symptomatic ICAS, defined as 50–99% stenosis of an intracranial artery (intracranial vertebral, basilar, distal ICA, or M1 MCA), confirmed by vascular imaging and associated with a qualifying ischemic event. Patients with only high-grade stenosis (70-99%) were included in this analysis. The primary outcome was to determine predictors of recurrent ischemic stroke in the territory of the symptomatic artery within 90 days of the index event. Baseline demographic, clinical, and imaging characteristics were recorded. Multivariable Cox proportional hazards regression with stepwise selection (p < 0.1) was used to identify independent predictors of recurrence; model discrimination was assessed using Harrell’s C-statistics. Results: Among 2,050 patients, 1,476 had high-grade (70-99%) symptomatic ICAS. The mean age was 67 ± 12.5 years, and 767 (55%) were male. Most patients were non-Hispanic (90.1%), taking dual antiplatelet therapy (77.8%), and statins (94.5%). Recurrent stroke occurred in 160 patients (10.8%) within 90 days. In multivariable Cox model, independent predictors of recurrence included atrial fibrillation (HR 2.05; 95% CI, 1.26–3.33; p = 0.004), hyperlipidemia (HR 1.57; 95% CI, 1.10–2.24; p = 0.014), diabetes mellitus (HR 1.36; 95% CI, 0.98–1.88; p = 0.064), and home use of dual antiplatelet therapy (HR 1.60; 95% CI, 1.01–2.54; p = 0.043)(Harrell’s C-statistic=0.62). In patients who underwent perfusion(n=402), mistmatch >10seconds were associated with increased recurrence (HR 1.80; 95% CI 0.95-3.38, p=0.07) and atrial fibrillation (HR 2.06: 95% CI 0.03-4.60, p=0.78) though did not reach statistical significance. Conclusion: In this population, diabetes, hyperlipidemia, atrial fibrillation, and prior use of dual antiplatelet therapy were associated with increased risk of 90-day recurrent ischemic stroke. Perfusion imaging may help identify high-risk patients who could benefit from intensified secondary prevention.

Background Advancement in neurointervention is frequently driven by the introduction of new technology and devices that improve procedural efficacy and patient outcomes. For physician-innovators, customer discovery—or the process of directly engaging with end users to explore workflows and associated challenges—offers a structured way to identify meaningful problems and guide early innovation. This primer aims to outline stepwise guidance for conducting customer discovery within neurointervention to characterize key areas of unmet need. Methods We detail stepwise guidance for conducting customer discovery founded on foundational business literature. To illustrate this process, we conducted five interviews with expert neurointerventionalists engaged in clinical innovation. Interview transcripts were reviewed and analyzed to track emerging themes, and responses were synthesized into a neurointerventionalist customer profile. Results Responses from interviewed neurointerventionalists suggested that safer vascular access, tools to support treatment prognostication, and condition-specific device design are unmet areas of need. Moreover, interviews revealed broader concerns about stagnation in device innovation and barriers within regulatory and institutional pathways. Conclusions Structured customer discovery identifies unmet needs that may be overlooked when device development is solely driven by technical breakthroughs or published outcomes. By outlining an actionable framework for customer discovery in neurointervention, we provide a practical model for aligning future innovation with real-world clinical challenges.

BACKGROUND: Intracranial atherosclerosis (ICAS) is associated with an increased risk of early recurrent ischemic stroke. We evaluated whether biomarkers of impaired distal perfusion—specifically, anterior circulation borderzone infarct, and hypoperfusion mismatch volume—were associated with recurrent ischemic stroke within 90 days. METHODS: The BIORISK ICAS (Biomarkers and Recurrence Risk in Symptomatic Intracranial Atherosclerosis) is a multicenter retrospective international study (35 sites) that included hospitalized patients with symptomatic ICAS (50%–99% luminal stenosis of the intracranial vertebral, basilar, distal internal carotid, or proximal middle cerebral artery) from January 2019 to June 2024. The primary outcome was recurrent ischemic stroke in the territory of the symptomatic artery within 90 days. In the primary analysis, the exposure was an acute anterior circulation borderzone infarct. In secondary analysis of the subset with presentation within 72 hours of last known normal and perfusion imaging completed, the exposure of interest was prespecified as hypoperfusion mismatch volume at T max (time to maximum) threshold of 6 seconds, dichotomized at the Youden index. We performed multivariable Cox regression to test associations between exposure variables and the outcome, adjusting for clinically relevant variables and those associated with the outcome ( P <0.1). RESULTS: Of 2050 patients with symptomatic ICAS, 1737 (84.7%) presented within 72 hours of symptom onset, among whom 509 (29.3%) underwent perfusion imaging. The primary analysis included 1891 patients; 174 (9.2%) patients had recurrent ischemic stroke in the symptomatic arterial territory. In adjusted Cox regression models, there was an association between anterior circulation borderzone infarct and recurrent ischemic stroke at 90 days (adjusted hazard ratio, 1.40 [95% CI, 1.02–1.93]). In the perfusion imaging analysis, hypoperfusion mismatch of ≥10 mL was associated with recurrent ischemic stroke (adjusted hazard ratio, 1.83 [95% CI, 1.03–3.28]). CONCLUSIONS: Biomarkers of impaired distal perfusion, anterior circulation borderzone infarct, and hypoperfusion mismatch were associated with increased risk of recurrent ischemic stroke. These findings support the use of perfusion imaging in ICAS as well as future trials investigating early reperfusion in high-risk patients with ICAS.

Background and objectives Arteriovenous malformations (AVMs) with perinidal aneurysms and single draining vein are associated with an elevated risk of rupture and increased procedural complexity. The role of preoperative embolization in this high-risk anatomical subset remains unclear. This study aimed to evaluate the safety and efficacy of microsurgery with preoperative embolization, compared with microsurgery alone in patients with such AVMs. Methods We conducted a multicenter retrospective analysis of an AVM registry from the MISTA (Multicenter International Study for Treatment of Brain AVMs) consortium and included AVMs with perinidal aneurysms and a single draining vein. Baseline characteristics, angiographic outcomes, functional outcomes, and complication rates were compared. Propensity score weighting (PSW) using the covariate balancing method was applied to adjust for baseline differences. Results Out of a total of 1919 patients, 65 met the inclusion criteria; 45 patients underwent preoperative embolization followed by microsurgery, and 20 underwent microsurgery alone. After adjustment, complete obliteration rates were similar between groups (OR 0.87, 95% CI 0.04 to 16.33, P=0.92), as were rates of functional independence at discharge and follow-up. Overall complication, symptomatic complication, and mortality rates did not differ significantly between groups. However, permanent complications were significantly lower in patients with preoperative embolization (OR 0.06, 95% CI 0.004 to 0.84, P=0.03). Discussion In patients with AVMs featuring perinidal aneurysms and single draining vein, preoperative embolization followed by microsurgery was associated with fewer permanent complications and no increase in adverse outcomes compared with microsurgery alone. However, given the small number of events, this finding should be interpreted cautiously.

Aim: According to the results of the MASTRO I living systematic review and meta-analysis, use of the EmboTrap Revascularization ® Device in the treatment of acute ischemic stroke (AIS) results in higher rates of good functional outcomes (90-day modified Rankin Scale [mRS] 0–2) compared with use of the Trevo ® Retriever or the Solitaire™ Revascularization Device. The aim of this analysis was to assess the potential economic impact of achieving improved functional outcomes for three commonly used stent retrievers (SRs) in the treatment of AIS. Methods: An economic model with short-term and long-term costs, representing a healthcare system perspective was developed using a decision tree to simulate a cohort of 1000 hypothetical patients treated for AIS with mechanical thrombectomy (MT) using EmboTrap, Trevo or Solitaire SRs. Based on the proportion of patients who achieved a 90-day mRS score of 0–2 or 3–5 for each device reported in MASTRO I (excluding patients not surviving after 90 days), this model estimated per-patient costs and the associated incremental cost savings. Results are reported from the healthcare system perspective in the US, Canada, the UK, Sweden, Germany, France, Italy, Spain, Belgium and The Netherlands. Results: Across all ten countries, the use of EmboTrap during MT was associated with the lowest short-term (ranging from €8412 in Italy to $66,525 in the US), long-term (ranging from €5249 in Italy to $25,757 in the US) and total (ranging from €13,661 in Italy to $92,282 in the US) per-patient costs. The total per-patient cost was higher with Trevo (ranging from €14,601 in Italy to $97,487 in the US) and Solitaire (ranging from €14,840 in Italy to $98,814 in the US). Cost savings were highest when comparing EmboTrap versus Solitaire, followed by EmboTrap versus Trevo, with Trevo versus Solitaire having the smallest cost savings. Results of sensitivity and scenario analyses supported the robustness of the base-case results. Conclusion: Across the ten countries, treating patients with AIS with EmboTrap resulted in lower short-term, long-term and total costs to the payer. With rising healthcare costs and limited hospital budgets, these results suggest EmboTrap proves to be an evidence-based economical choice of SR for hospitals and healthcare systems.

BACKGROUND: The EXCELLENT registry aimed to evaluate the effectiveness of the EMBOTRAP Revascularization Device in an all-comer population in a real-world setting, with a focus on the composition of retrieved clots. METHODS: EXCELLENT is a prospective, global registry of patients with acute ischemic stroke treated with EMBOTRAP as the first-line mechanical thrombectomy device conducted at 34 sites (25 sites contributing clot) from September 2018 to March 2021, utilizing core imaging and central histology laboratories blinded to clinical data, independent 90-day modified Rankin Scale assessment and Clinical Events Committee. RESULTS: After screening 3799 patients, a total of 997 subjects (mean age, 70.0±14.2 years; 51.8% women; 19.7% non-White) were included. The first-pass modified Treatment in Cerebral Infarction (mTICI) ≥2b rate was 64.5% (623/966), first-pass mTICI ≥2c was 39.1% (378/966), and final mTICI ≥2b was 94.5% (931/985). A total of 427/912 (46.8%) patients achieved a 90-day modified Rankin Scale of 0 to 2 or ≤baseline. Embolization to a new territory occurred in 0.2% (2/984), and symptomatic intracranial hemorrhage at 24 hours in 1.6% (16/997). The 90-day mortality was 19.1% (175/918). Device- and/or procedure-related serious adverse events occurred in 5.9% (54/912) through 90 days. The mean RBC percentage of retrieved clots was 45.62±21.372. Among patients who achieved mTICI ≥2b with the first pass, 15.7% (52/331) and 9.7% (32/331), respectively, had RBC-poor (<25%) and RBC-rich (>75%) clots. Patients with no clot retrieved in any procedural pass had a lower percentage of hyperdense or susceptibility vessel sign on baseline imaging (58.9% versus 74.7%; P <0.001), pointing to a potential preprocedure indicator of challenging clot. CONCLUSIONS: The EXCELLENT registry informs real-world practices in mechanical thrombectomy and sheds light on the range of clots effectively retrieved by current technology. This is the first report of detailed patient characteristics where mechanical thrombectomy maneuvers failed to remove any clot material. Although the composition of nonretrievable clots cannot be assessed histologically, the results support the notion that no retrieval may be correlated with imaging findings suggesting clots lower in RBC. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT03685578.

Aim: The aim of this analysis was to assess the cost–effectiveness of the EmboTrap ® Revascularization Device compared with the Solitaire™ Revascularization Device and Trevo ® Retriever for the treatment of acute ischemic stroke (AIS) from the perspective of the Chinese healthcare system. Methods: According to MASTRO I, a recent living systematic literature review and meta-analysis, mechanical thrombectomy (MT) with EmboTrap in the treatment of AIS resulted in better functional outcomes compared with the use of Solitaire or Trevo. Based on the proportion of patients that achieved 90-day modified Rankin Scale (mRS) scores of 0–2, 3–5 and 6 reported in MASTRO I, a combined 90-day short-term decision tree and Markov model with a 10-year time horizon was used to compare the cost–effectiveness of the three devices. The primary outcome was the incremental cost–effectiveness ratio (ICER), representing the incremental cost (in 2022 Chinese Yuan [CNY]) per incremental quality-adjusted life-year (QALY). The ICERs were compared against willingness-to-pay (WTP) thresholds of 1, 1.5 and 3-times the 2022 national gross domestic product (GDP) per capita in China. Results: Treatment with EmboTrap resulted in total QALYs of 3.28 and total costs of 110,058 CNY per patient. Treatment with Trevo resulted in total QALYs of 3.05 and total costs of 116,941 CNY per patient. Treatment with Solitaire resulted in total QALYs of 2.81 and total costs of 99,090 CNY per patient. Trevo was dominated by EmboTrap as it was a more costly and less effective intervention. As such, Trevo was not cost-effective at any WTP threshold. Compared with Solitaire, EmboTrap was more effective and more costly, with an ICER of 23,615 CNY per QALY. This result suggests that EmboTrap is cost-effective when compared with Solitaire since the ICER was lower than all WTP thresholds assessed. Conclusion: EmboTrap dominated Trevo and is cost-effective for the treatment of patients with AIS compared with Solitaire when assessed from the perspective of the Chinese healthcare system and based on the device-level meta-analysis MASTRO I. Selecting a stent retriever (SR) that optimizes 90-day mRS score is an important consideration from both a clinical and healthcare payer perspective in China as it is associated with reduced long-term costs and increased quality of life.

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.

Background Studies during the COVID-19 pandemic have demonstrated an association between COVID-19 virus infection and the development of acute ischemic stroke, particularly large vessel occlusion (LVO). Studying the characteristics and immunohistochemistry of retrieved stroke emboli during mechanical thrombectomy for LVO may offer insights into the pathogenesis of LVO in COVID-19 patients. We examined retrieved COVID-19 emboli from the STRIP, EXCELLENT, and RESTORE registries and compared their characteristics to a control group. Methods We identified COVID-positive LVO patients from the STRIP, RESTORE, and EXCELLENT studies who underwent mechanical thrombectomy. These patients were matched to a control group controlling for stroke etiology based on Trial of Org 10172 in Acute Stroke Treatment criteria. All clots were stained with Martius Scarlet Blue (MSB) along with immunohistochemistry for interleukin-6 (IL-6), C-reactive protein (CRP), von Willebrand factor (vWF), CD66b, fibrinogen, and citrullinated Histone H3. Clot composition was compared between groups. Results Nineteen COVID-19-positive patients and 38 controls were included. COVID-19-positive patients had a significantly higher percentage of CRP and vWF. There was no difference in IL-6, fibrin, CD66b, or citrullinated Histone H3 between groups. Based on MSB staining, there was no statistically significant difference regarding the percentage of red blood cells, white blood cells, fibrin, and platelets. Conclusions Our study found higher concentrations of CRP and vWF in retrieved clots of COVID-19-positive stroke patients compared to COVID-19-negative controls. These findings support the potential role of systemic inflammation as indicated by elevated CRP and endothelial injury as indicated by elevated vWF as precipitating factors in thrombus development in these patients.

Introduction Acute stroke patients presenting with large vessel occlusion secondary to intracranial atherosclerosis (ICAS‐LVO) may require rescue therapy (RT) in addition to mechanical thrombectomy (MT) to achieve and maintain successful recanalization. We performed a systematic review and meta‐analysis of comparative studies that reported outcomes of RT in ICAS‐LVO patients to evaluate its safety and efficacy. Methods Databases searched include PubMed, CINAHL Complete, and Scopus from database date of inception through August 17, 2021. We included comparative studies that reported the outcomes of ICAS‐LVO RT compared to outcomes of ICAS‐LVO patients who did not undergo RT or to those presenting with embolic LVO patients (non‐ICAS LVO). Meta‐analysis using the random effects model was used to combine estimates reporting odds ratios (OR) and 95% confidence intervals (CI). Results Total of 9 nonrandomized studies were included: 5 studies in ICAS‐LVO RT vs. ICAS‐LVO non‐RT analysis and 5 ICAS‐LVO RT vs. non‐ICAS LVO analysis. Rescue treatments included intra‐arterial antiplatelets, angioplasty, stenting or combination of treatments. Compared to non‐RT ICAS LVO, RT was associated with increased favorable 90‐day outcome (OR 3.19, 95% CI 1.91‐5.32, I2 14%) and decreased 90‐day mortality (OR 0.35, 95% CI 0.16‐0.76, I2 21%) (Figure 1). In the analysis of ICAS LVO vs embolic LVO, the incidence of favorable 90‐day outcome and 90‐day mortality did not differ between the ICAS‐LVO RT and non‐ICAS LVO (OR 0.97, 95% CI 0.58‐1.64, I2 50%) and (OR 1.22, 95% CI 0.90‐1.66, I2 0%), respectively. Conclusions Rescue treatment is associated with better outcomes in ICAS‐LVO patients. The outcomes of ICAS‐LVO patients who receive RT may be comparable to embolic LVO patients (non‐ICAS LVO).