Abstract Number ‐ 209: Short‐ and long‐term outcomes of mechanical thrombectomy in acute ischemic stroke patients with active cancer

Introduction We aim to investigate the difference in mechanical thrombectomy (MT) outcome for cancer‐related stroke (CRS) with active and inactive cancer. Methods Of the consecutive acute ischemic stroke (AIS) patients admitted to our institute from 2010 to 2021, patients with cancer who received MT within 24 hours of onset and were enrolled.Outcomes including the favorable outcome (modified Rankin Scale score of 0 to 2) at3 months, 1‐year,and death within 3 months or 1‐yearwere assessed between patients with active and inactive cancer among patients with cancer. The rate offirst pass effect (FPE, extendedThrombolysis in Cerebral Infarction[eTICI] 2c/3 after first pass) and final eTICI 2c/3 achievement were also assessed. Active cancer was defined as a cancer that was diagnosed within 6 months; required chemotherapy or surgical treatment within 6 months; or was recurrent, metastatic, or inoperable. Results Of 59 patients (26 women; median age, 80 years; median NIH Stroke Scale score[NIHSS] 17), 19 (32.2%) patients had an active cancer. Patients with active cancer has less atrial fibrillation (47% vs. 78%,P< 0.01) and higher medianD‐dimer(4.60μg/mLvs. 2.00μg/mL,P< 0.01). There were no significant differences in the favorable outcome at 3 months (26% vs. 45%,P = 0.26) and at 1 year (26% vs. 45%,P = 0.26) between both groups, but death within 3 months (32% vs. 5%,P< 0.01) and within 1 year (42% vs. 8%,P< 0.01) were more frequent in patients with active cancer than those with inactive cancer. Conclusions Long‐term clinical outcomes of patients with active cancer were worse than those with inactive cancer

Abstract 205: Efficacy and Safety of Mechanical Thrombectomy for Primary MeVO with Disabling Deficit

Introduction We aimed to evaluate the efficacy and safety of mechanical thrombectomy (MT) for medium vessel occlusion (MeVO) with the disabling deficit. Methods The study period was from January 2011 to December 2022. Inclusion criteria were 1) within 24 hours of stroke onset, 2) prestroke mRS score ≤1, 3) NIHSS score ≥4 or disabling deficit (complete hemianopia (≥2 on NIHSS), severe aphasia (≥2 on NIHSS), visual sensory extinction (≥1 on NIHSS), significant weakness with NIHSS subscore of paralysis ≥2), 4) MeVO (MCA distal M2, M3, ACA A1, A2, A3, PCA P1, P2, and P3). Outcomes were compared between the MT and standard medical treatment (SMT) groups. Outcome was defined as the favorable outcome (mRS score 0‐2 at 90 days), death within 90 days, and symptomatic intracranial hemorrhage (SICH). Results Of all, 192 patients (72 women, median age 78 years, median NIHSS score 11 points) were enrolled, and 76.6% (n=147) had distal M2 occlusion. Compared to the SMT group (n=153), the MT group (n=39) had a significantly larger median Tmax>10 sec volume (median 25 mL vs. 5 mL, P 6‐sec volume (61 mL vs. 44 mL, P<0.01), while median NIHSS score (13 vs. 11, P=0.69) and intravenous thrombus (51.6％ vs. 55.3%, P=0.72) were significantly lower in the MT group. There were significantly more patients in the MT group with a favorable outcome (73.7% vs. 54.1%, adjusted odds ratio 2.59 95% confidence interval 1.07‐6.24), death within 90 days (7.9% vs. 3.1%), SICH (5.3% vs. 4.4%) were not significantly different. In subgroup analysis, MT was independently associated with age (<80 years; 1.33, 1.21‐15.57, P=0.222) and neurological severity (NIHSS ≥10 points; 2.79, 1.07‐7.24, P=0.870) for a favorable outcome. Conclusion In MeVO with disabling deficits, MT was independently associated with more favorable outcomes than the SMT group

Tmax Mismatch Ratio to Identify Intracranial Atherosclerotic Stenosis‐Related Large‐Vessel Occlusion Before Endovascular Therapy

Background We aimed to clarify which time‐to‐maximum of the tissue residue function (Tmax) mismatch ratio is useful in predicting anterior intracranial atherosclerotic stenosis (ICAS)–related large‐vessel occlusion (LVO) before endovascular therapy. Methods and Results Patients with ischemic stroke who underwent perfusion‐weighted imaging before endovascular therapy for anterior intracranial LVO were divided into those with ICAS‐related LVO and those with embolic LVO. Tmax ratios of >10 s/>8 s, >10 s/>6 s, >10 s/>4 s, >8 s/>6 s, >8 s/>4 s, and >6 s/>4 s were considered Tmax mismatch ratios. Binominal logistic regression was used to identify ICAS‐related LVO, and the adjusted odds ratio (aOR) and 95% CI for each Tmax mismatch ratio increase of 0.1 were calculated. A similar analysis was performed for ICAS‐related LVO with and without embolic sources, using embolic LVO as the reference. Of 213 patients (90 women [42.0%]; median age, 79 years), 39 (18.3%) had ICAS‐related LVO. The aOR (95% CI) per 0.1 increase in Tmax mismatch ratio in ICAS‐related LVO with embolic LVO as reference was lowest with Tmax mismatch ratio >10 s/>6 s (0.56 [0.43–0.73]). Multinomial logistic regression analysis also showed the lowest aOR (95% CI) per 0.1 increase in Tmax mismatch ratio with Tmax >10 s/>6 s (ICAS‐related LVO without embolic source: 0.60 [0.42–0.85]; ICAS‐related LVO with embolic source: 0.55 [0.38–0.79]). Conclusions A Tmax mismatch ratio of >10 s/>6 s was the optimal predictor of ICAS‐related LVO compared with other Tmax profiles, with or without an embolic source before endovascular therapy. Registration clinicaltrials.gov. Identifier NCT02251665

Outcomes of Symptomatic Anterior Large Vessel Occlusion by Initial Imaging Assessment Using Diffusion‐Weighted Imaging Versus Noncontrast Computed Tomography

Background We aimed to compare outcomes after stroke due to anterior circulation large vessel occlusion with initial imaging assessments using diffusion‐weighted imaging (DWI) or noncontrast computed tomography (NCCT). Methods Among 2399 patients with large vessel occlusion stroke in a prospective, multicenter registry, patients with (1) prestroke modified Rankin Scale scores 0 to 1, (2) occlusion of the internal carotid artery or M1 segment of the middle cerebral artery, and (3) onset‐to‐hospital‐arrival time <6 hours were included. The primary effectiveness outcome was good functional outcome, defined as modified Rankin Scale scores 0 to 2 at 3 months. Safety outcomes included symptomatic intracranial hemorrhage. Intergroup biases were accounted for by mixed‐effects multivariable modeling and inverse probability of treatment weighting. Results A total of 343 patients (130 women [37.9%]; median age, 74 years [interquartile range, IQR, 66–82 years]) were analyzed. DWI‐based assessment was performed in 217 patients, and NCCT‐based assessment was performed in 126 patients. The DWI group showed a lower baseline National Institutes of Health Stroke Scale score (P<0.01) and lower Alberta Stroke Program Early CT Score (P<0.01) than the NCCT group. Frequency of endovascular therapy was lower in the DWI group (71.9%) than in the NCCT group (84.1%; P<0.01). Median hospital‐arrival‐to‐arterial‐puncture time was 55 minutes (IQR, 40–77.5 minutes) in the DWI group and 55 minutes (IQR, 35–80 minutes) in the NCCT group (P=0.89), with similar rates of successful recanalization (77.6% versus 76.4%, respectively; P=0.88). Frequency of good functional outcome was 47.0% in the DWI group and 41.3% in the NCCT group (adjusted odds ratio, 1.32; 95% CI, 0.49–3.55). Symptomatic intracranial hemorrhage was encountered in 2.8% in the DWI group and 1.6% in the NCCT group (P=0.71). Conclusions Potential difference in accuracy of ischemic damage assessment between the 2 modalities did not seem to affect outcomes of anterior circulation large vessel occlusion stroke. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02419794

Abstract 1122‐000009: Impact of RNF213 p.R4810K Variant on Endovascular Therapy Outcome for Acute Large Vessel Occlusion Stroke

Introduction: The ring finger protein 213 gene (RNF213) has been identified as a susceptibility gene for moyamoya disease, and the p.R4810K polymorphism as a founder variant commonly found in East Asian patients. 1  A recent large case‐control study including over 46,958 Japanese subjects reported that the RNF213 p.R4810K variant was a strong risk factor for Japanese cerebral infarction: the variant was found in 5.2% of patients with non‐cardioembolic stroke and in 2.1% of healthy controls. 2   Mechanical thrombectomy (MT) is a standard treatment for acute ischemic stroke due to occlusion of the internal carotid artery and M1 segment of the middle cerebral artery, but in East Asians, about 15–25% of LVOs for which MT was performed were reportedly caused by intracranial atherosclerotic disease (ICAD). 3  RNF213 p.R4810K variant may be involved to some extent in ICAD‐related LVO of Asian patients undergoing MT. In this study, we aimed to investigate the impact of RNF213 p.R4810K variant on EVT for anterior circulation LVO stroke. Methods: Of the consecutive ischemic stroke patients from 2011 to 2021 seen in our institute, patients who underwent EVT for acute occlusion of the intracranial ICA or M1 segment of MCA and signed a consent form for RNF213 genotyping were included. Outcomes were instant re‐occlusion, final modified Thrombolysis in Cerebral Infarction (mTICI) ≥2b reperfusion, early re‐occlusion, and modified Rankin Scale (mRS) score 0–2 at 90 days. Instant re‐occlusion was defined as occurrence of re‐occlusion during the procedure, whereas early re‐occlusion as re‐occlusion detected on magnetic resonance angiography within 2 weeks after confirmation of successful reperfusion at the end of the procedure. 4 Results: Of the 277 patients (128 women [46.2%]; median age, 76 years) analyzed, 10 (3.6%) patients had the RNF213 p.R4810K variant. The variant carriers were younger (67 years vs. 76 years, P<0.01), more frequently received angioplasty (40.0% vs. 12.0%, P<0.01), and more frequently had intracranial atherosclerotic disease‐related LVO as a cause of acute LVO (70.0% vs. 8.6%, P<0.01) than non‐carriers. The variant carriers showed higher rates of instant re‐occlusion (40.0% vs. 5.6%, P<0.01), but there were no statistically significant inter‐group differences for the final mTICI ≥2b reperfusion rate between carriers and non‐carriers (100.0% vs. 81.6%, P = 0.22). Early re‐occlusion was more frequent in the variant carriers than non‐ carriers (60.0% vs. 0.4%, P<0.01) with no intergroup difference in the rate of repeated EVT (67.7% vs. 100.0%, P = 0.71). There were no statistically significant inter‐group differences for achievement of mRS score 0–2 (60.0% vs. 51.7%, P = 0.75) Conclusions: Both instant and early re‐occlusion were more frequent in the RNF213 p.R4810K variant carriers who had received EVT for acute anterior circulation LVO than in the non‐carriers. Potential impact of RNF213 polymorphism status on EVT outcomes was clarified

Impact of the RNF213 p.R4810K Variant on Endovascular Therapy for Large‐Vessel Occlusion Stroke

Background We investigated the impact of the ring finger protein 213 p.R4810K variant, a founder variant for moyamoya disease in East Asians, on endovascular therapy outcomes in patients with acute anterior‐circulation large‐vessel occlusion stroke in comparison with noncarriers. Methods Of the consecutive patients with ischemic stroke admitted to our institute from 2011 to 2021, patients who underwent endovascular therapy for acute occlusion of the intracranial internal carotid artery or M1 segment of the middle cerebral artery were included. Outcomes were instant reocclusion, final modified Thrombolysis in Cerebral Infarction reperfusion ≥2b, and early reocclusion. Instant reocclusion was defined as the occurrence of reocclusion during the procedure, and early reocclusion was defined as reocclusion detected on magnetic resonance angiography within 2 weeks after the confirmation of successful reperfusion. Results Of the 277 patients analyzed (128 women; median age, 76 years), 10 patients (3.6%) carried the ring finger protein 213 p.R4810K variant. Variant carriers were younger (P=0.01) and more frequently had intracranial atherosclerotic disease‐related large‐vessel occlusion as a cause of acute large‐vessel occlusion (P<0.001) compared with noncarriers. Variant carriers showed a higher rate of instant reocclusion (70.0% versus 5.6%; P<0.001), but there were no significant intergroup differences in the final modified Thrombolysis in Cerebral Infarction ≥2b reperfusion rate between carriers and noncarriers (100.0% versus 81.6%, respectively; P=0.22). Early reocclusion was more frequent in variant carriers compared with noncarriers (60.0% versus 0.4%; P<0.001). Conclusions Instant and early reocclusions were more frequent in variant carriers who underwent endovascular therapy for acute anterior‐circulation large‐vessel occlusion compared with noncarriers