Search

Background and Purpose: We sought to investigate the impact of COVID-19 pandemic on number of acute stroke patients admitted to Japanese primary stroke centers (PSCs). Methods: The Japan Stroke Society and the MHLW registry of mechanical thrombectomy for acute ischemic stroke conducted a national annual survey of hospitalization volumes for acute ischemic stroke, intracranial cerebral hemorrhage, and subarachnoid hemorrhage in PSCs. Number of acute stroke patients was defined as sum of three stroke subtypes admitted within 7 days after the onset. Monthly acute stroke volumes were compared between 2019 and 2020, among COVID-19 waves, and regional infectious rates. Results: The stroke volume data was completed in 530 PSCs. The annual acute stroke volume was declined 2.5% from 179,893 in 2019 to 174,385 in 2020. Number of acute stoke patients was declined during COVID-19 expanding periods (1 st wave, Mar-May; 2 nd wave Jul-Aug; 3 rd wave Nov-Dec), whereas it was increased in the other months. The mean decline rate of stroke volumes from 2019 to 2020 was greater in 125 PSCs located in prefectures with high estimated SARS-CoV 2 infected rate (more than 2,300 per million people) than in 405 PSCs of the other regions (-4.6±15.4% vs -0.1±20.0%, P=0.008), especially during COVID-19 expanding periods (-8.2±17.9% vs -3.1±21.3%, P=0.009). Conclusions: Acute stroke volumes were declined in 2020 from 2019 in Japanese PSCs, especially during COVID-19 expanding periods and in highly infected regions. The overwhelmed health care system and infection control practices may have associated with decline of number of acute stroke patients during COVID-19 pandemic.

Background and Purpose— The clinical course of acute ischemic stroke with large vessel occlusion (LVO) is a multifactorial process with various prognostic factors. We aimed to model this process with machine learning and predict the long-term clinical outcome of LVO before endovascular treatment and to compare our method with previously developed pretreatment scoring methods. Methods— The derivation cohort included 387 LVO patients, and the external validation cohort included 115 LVO patients with anterior circulation who were treated with mechanical thrombectomy. The statistical model with logistic regression without regularization and machine learning algorithms, such as regularized logistic regression, linear support vector machine, and random forest, were used to predict good clinical outcome (modified Rankin Scale score of 0–2 at 90 days) with standard and multiple pretreatment clinical variables. Five previously reported pretreatment scoring methods (the Pittsburgh Response to Endovascular Therapy score, the Stroke Prognostication Using Age and National Institutes of Health Stroke Scale index, the Totaled Health Risks in Vascular Events score, the Houston Intra-Arterial Therapy score, and the Houston Intra-Arterial Therapy 2 score) were compared with these models for the area under the receiver operating characteristic curve. Results— The area under the receiver operating characteristic curve of random forest, which was the worst among the machine learning algorithms, was significantly higher than those of the standard statistical model and the best model among the previously reported pretreatment scoring methods in the derivation (the area under the receiver operating characteristic curve were 0.85±0.07 for random forest, 0.78±0.08 for logistic regression without regularization, and 0.77±0.09 for Stroke Prognostication using Age and National Institutes of Health Stroke Scale) and validation cohorts (the area under the receiver operating characteristic curve were 0.87±0.01 for random forest, 0.56±0.07 for logistic regression without regularization, and 0.83±0.00 for Pittsburgh Response to Endovascular Therapy). Conclusions— Machine learning methods with multiple pretreatment clinical variables can predict clinical outcomes of patients with anterior circulation LVO who undergo mechanical thrombectomy more accurately than previously developed pretreatment scoring methods.

Background and Purpose: Outcomes in patients ≥90 years of age with stroke due to large vessel occlusion were compared between endovascular therapy (EVT) and medical management. Methods: Of 2420 acute ischemic stroke patients with large vessel occlusion in a prospective, multicenter, nationwide registry in Japan, patients aged ≥90 years with occlusion of the internal carotid artery or M1 segment of the middle cerebral artery were included. The primary effectiveness outcome was a favorable outcome at 3 months, defined as achieving a modified Rankin Scale score of 0 to 2 or return to at least the prestroke modified Rankin Scale score at 3 months. Safety outcomes included symptomatic intracranial hemorrhage within 72 hours after onset. Intergroup biases were adjusted by multivariable adjustment with inverse probability of treatment weighting. Results: A total of 150 patients (median age, 92 [interquartile range, 90–94] years; median prestroke modified Rankin Scale score, 2 [interquartile range, 0–4]) were analyzed. EVT was performed in 49 patients (32.7%; mechanical thrombectomy, n=43). The EVT group showed shorter time from onset to hospital arrival ( P =0.03), higher Alberta Stroke Program Early CT Score ( P P P P =0.30). Conclusions: Patients who underwent EVT showed better functional outcomes than those with medical management without increased symptomatic intracranial hemorrhages. Given proper patient selection, withholding EVT solely on the basis of the age of patients may not offer the best chance of good outcome. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT02419794.

Background and Purpose: Efficacy of mechanical thrombectomy for acute cerebral large vessel occlusion depends on time from symptom onset to reperfusion. While time to treatment in hospital has been optimized in these days, it is not well-known about improving time in pre-hospital when suspected stroke. We sought to analyze time from emergency medical services (EMS) dispatch to arterial puncture in stroke patients eligible for mechanical thrombectomy. Methods: We analyzed time components from EMS dispatch to puncture in patients with acute large vessel occlusion within 6 hours from onset treated with mechanical thrombectomy between April 2015 and December 2018. We assessed the associated factors with each time component and patient outcomes. Results: Consecutive 195 patients were included in this analysis. The median EMS dispatch-to-scene, on-scene, transport, door-to-puncture (DTP), and scene-to-puncture (STP) times were 4, 16, 12, 40, and 70 minutes, respectively. Percentage of favorable outcomes were significantly higher in patients with STP within 60 minutes (57.5% vs 35.8%, p Conclusions: Reducing time in pre-hospital and in-hospital interact with each other. Education program and use of direct call from EMS contributed to reducing these times.

Objective: To show safety and efficacy of mechanical thrombectomy (MT) for acute stroke using TRON-FX in Japanese approving trial. Material and Methods: This trial is multi center, prospective, single arm, registry study of new stent retriever, TRON-FX, Biomedical Solutions, Tokyo, Japan. TRON-FX have 2 size variation, 4mm diameter/20mm length and 2/15, smallest in the world. Inclusion criteria are 1) acute ischemic stroke (AIS) aged 20-85, 2) from onset to start MT within 8 hours, 3) IV rt-PA is ineligible or ineffective, 4) confirm occlude ICA, M1/M2/M3, VA, BA, and P1/P2. 5) NIHSS score 8 or more. Primary endpoint is immediate post procedural recanalization (up to 3 times by TRON-FX)and symptomatic intracranial hemorrhage (ICH) at 24 hours. Secondary endpoints are 1) good neurological outcome (mRS 0-2) at 90days, 2) symptomatic and asymptomatic ICH at 24 hours, 3) Mortality within 90days and 4) device-related or procedure-related serious adverse events at day 90. Results: 50 patients enrolled and first patient in was 2017/9/27 and last patient in was 2017/11/5. All patient followed 90 days. Median age is 75, raged 44-86, male gender is 62% (31/50), occluded vessels are ICA(2) 4%, MCA/M1(23) 46%, MCA/M2M3(26) 52%, BA(3) 6%, PCA(1) 2%, IV rt-PA failed(37) 74%, median baseline NIHSS score is 17, ranged 8-29, and median mRS prior to stroke 0. The primary endpoint, recanalization TICI 2b or better was 40(80%), and symptomatic ICH was 1(2%). More over, the secondly endpoint, 1) mRS 0-2 at 90 days was 25/47(53.2%), 2) symptomatic and asymptomatic ICH was 15(30%), 3) mortality was 4(8%) and 4) no device-related or procedure-related serious adverse event. Conclusions: TRON FX approving trial in Japan has proved great efficacy and safety of this thrombectomy device with high recanalization rate with less intracranial hemorrhage, especially for distal and small vessel. Clinical Trial gov. IDNCT02964702

Background and Purpose: Clinical outcomes after successful endovascular therapy in patients with acute ischemic stroke are associated with several factors including onset-to-reperfusion time (ORT). The objective of the current study was to assess whether ORT is associated with outcomes in elderly. Methods: Among 2420 patients enrolled in the RESCUE 2 study, a prospective stroke registry with acute cerebral large-vessel occlusion at 46 centers between October 2014 and January 2017, we enrolled 397 elderly patients more than 80 with successful reperfusion after thrombectomy (thrombolysis in cerebral infarction [TICI] score of 2b or 3) in the current analysis. The rates of good outcome (modified Rankin Scale [mRS] scores of 0-2 at 3 months) were compared among the three categories of ORT ( Results: The rates of good outcome were 41% (30/73), 34% (26/77), and 25% (62/247) in each category of ORT. Odds ratio and 95% confidence interval for good outcome were 0.68 and 0.49-0.94 per 1 category delay. Conclusion: ORT was associated with good outcome even in elderly patients.

Background and Purpose: Recent studies have demonstrated that endovascular reperfusion therapy improves clinical outcomes at 90 days after ischemic stroke. However, effects on long-term outcomes are not well known. The objective of the current study was to assess whether successful reperfusion was associated with a temporal change in modified Rankin Scale (mRS) score from 90 days to 1 year after endovascular therapy. Methods: We retrospectively analyzed a database of consecutive patients with acute ischemic stroke who received endovascular therapy between April 2006 and March 2016 at 4 centers. We compared the incidences of improvement and deterioration in patients with successful reperfusion (i.e., modified thrombolysis in cerebral infarction score of 2b or 3) with those in patients with unsuccessful reperfusion. We defined improvement and deterioration as a decrease and an increase of 1 or more points on the mRS score from 90 day to 1 year after endovascular therapy, respectively. Results: A total of 268 patients were included in the current study. The rate of patients with improvement tended to be higher in patients with successful reperfusion than in patients with unsuccessful reperfusion (20% [34/167 patients] vs. 12% [12/101], P = 0.07). The rate of patients with deterioration was lower in patients with successful reperfusion than in patients with unsuccessful reperfusion (25% [42/167] vs. 42% [42/101], P < 0.01). After adjustment for confounders, successful reperfusion was associated with improvement (adjusted odds ratio, 2.65; 95% confidence interval, 1.23-5.73; P < 0.05) and deterioration (adjusted odds ratio, 0.33; 95% confidence interval, 0.18-0.62; P < 0.01), independent of the 90-day mRS score. Conclusions: Successful reperfusion has further beneficial effects on long-term outcomes beyond 90 days from stroke.

Background and Purpose: Endovascular therapy (EVT) for acute ischemic stroke (AIS) is now proven by pivotal randomized controlled trials (RCTs) to produce clinically large benefits. In early 2015, following publication of these RCTs, we implemented a new institutional acute stroke care protocol to improve outcomes of patients with AIS, especially by reducing onset-to-reperfusion (OTR) time. We sought to analyze the temporal trends in EVT for AIS at our hospital and evaluate the effect of this intervention. Methods: We analyzed the temporal trends in EVT for AIS and compared patients who underwent EVT for AIS in the pre intervention (April 2010 - March 2015) and post intervention (April 2015 - March 2017) period. Using univariate methods and multivariable logistic regression, we assessed the associated factors with favorable outcomes. Results: Among 2657 patients with AIS, 322 (12.1%) underwent EVT. The mean age was 74.4 and the median baseline NIHSS was 19. The percentage of patients with EVT significantly increased from 9.7% pre intervention to 18.0% post intervention. Patients over 90 years old, with M2 occlusion, and received IV-tPA were significantly increased in post intervention period (P Conclusions: EVT for AIS accelerated markedly in the two years following RCTs publication and our new institutional acute stroke care protocol reduced DTP and OTR times. Reducing OTR times was associated with improving patient outcomes.

Background and purpose: Although it is thought that hemodynamics is closely involved in recanalization after endovascular coil embolization of cerebral aneurysms, details are still not clear. Using computational flow dynamic (CFD) analysis, the aim of this study was to identify hemodynamic predictors specific to recanalization after complete coil embolization. Methods: We used patient-specific arterial geometries of 14 internal carotid artery-posterior communicating artery (ICPC) aneurysms after coil embolization. Pulsatile blood flow was simulated using ANSYS-CFX, based on the Navier-Stokes equations for incompressible fluid. As the pulsatile inlet boundary condition, we used a typical flow velocity waveform of internal carotid artery that was scaled based on the patient-specific mean velocity. In order to eliminate the influence due to aneurysm size between both groups, multivariate logistic regression analysis was performed using aneurysm size and each hemodynamic metric as independent variables to find hemodynamic predictors for recanalization after coil embolization. Results: With a follow-up of >1 year, 6 aneurysms were recanalized, and 8 cases were stable. Significant hemodynamic risk factors specific to recanalization were high values of metrics in association with disturbed flow, i.e. oscillatory shear index (OSI) [odds ratio (OR), 0.00115; 95% confidence interval (CI), 0.00102-0.00144; p = 0.017] and normalized transverse WSS (NtransWSS) (OR, 0.00103; 95%CI, 0.0010-0.00179; p = 0.043), but not flow rate of parent artery, aneurysmal mean velocity, or WSS magnitude-based metrics, including WSS and normalized WSS. Conclusions: These data suggest that enhanced disturbed flow plays a central role in recanalization after complete coil embolization of ICPC aneurysms. Imaging examinations at shorter intervals may be necessary if strong disturbed flow is observed in the aneurysm before surgery.

Background: It is widely known that the advantage of endovascular treatment (EVT) of unruptured intracranial aneurysms (UIAs) under local anesthesia (LA) is that neurologic evaluation of the patient during procedure can be performed unlike general anesthesia. However, there have been no literature about intraprocedural neurological deficit and their outcomes. Purpose: This study was performed to identify the causes and outcomes of intraprocedural neurological deficit in EVT under LA. Methods: We retrospectively evaluated the medical and radiologic data of 1068 UIAs (1050 patients) who underwent coil embolization from 2008 to 2016. Results: A total of 1015 procedure (1000 patients) were performed under LA. Intraprocedural neurological deficits were observed in 63 patients (6.3%). The causes were intraprocedural rupture in 13 (1.3%), thromboembolism in 16 (1.6%), intolerance against the balloon or guiding catheter in 19 (1.9%) and reduction of blood flow in 15 patients (1.5%) (thrombus formation in 12 and coil protrusion in 3 patients). The managements of coil protrusion were stent placement in 2 (66%) or balloon inflation in 1 procedure (33%) and those of intolerance were aborting procedures in 3 (16%), stent placement in 4 (21%) or simple technique without balloon catheter in 9 procedures (47%). Of the patients with intraprocedural deficits, 58 patients (92%) had good outcomes and 5 patients (8%) had poor outcomes. Conclusion: The morbidity rate in EVT of UIAs can be reduced by appropriate management of intraprocedural neurological deficit under LA.

Objective: The risk of rebleeding is reported higher in ruptured cerebral aneurysms treated with endovascular coiling than in patients treated with surgical clipping. In this study, we evaluate the time and risk factors of rebleeding after coil embolization of ruptured cerebral aneurysms. Methods: From April 2001 to August 2014, we performed coil embolization on 288 ruptured cerebral aneurysms. We evaluated the frequency, time and risk factors of rebleeding in terms of patient background, location, size, ratio of dome to neck, volume embolization ratio (VER), and remnant flow into aneurysms immediately after embolization. Results: We suffered 6 rebleedings (2.1%) within 24 hours after the initial coil embolization (early-rebleeding), and 6 rebleedings (2.1%) within 1 year after the embolization in the patients who we could follow up, and 3 rebleedings (late-rebleeding) 1 year later. All of early-rebleeding occurred within 12 hours. 5 of 6 rebleedings within 1 year after the embolization occurred within 3 months from 30 days after, and one patient who was administered warfarin suffered rebleeding 13 days after the treatment. Antihypertensive therapy after the embolization tended to prevent early-rebleeding (p=0.092), but we revealed no significant factor related to early-rebleeding. We demonstrated significant differences between ratio of dome to neck and rebleeding within 1 year after (p=0.035), and between angiographic result and rebleeding within 1 year after (p=0.001). Conclusions: Most of rebleeding after coil embolization occurred within 12 hours or within 3 months from 30 days after the treatment. We recommend antihypertensive therapy and the angiogram 1month after the coil embolization at our institution.

Background and purpose: The outcome after endovascular therapy in acute ischemic stroke is associated with onset-to-reperfusion time (ORT). The Totaled Health Risks in Vascular Events (THRIVE) score is also an important pre-thrapeutic predictor of outcome. We hypothesized that the therapeutic time window is narrower in patients with the higher THRIVE score. Methods: We retrospectively studied consecutive 109 ischemic stroke patients with successful reperfusion after endovascular therapy between October 2005 and March 2014 at a single institute (Kobe City Medical Center General Hospital). Inclusion criteria was as follows: National Institutes of Health Stroke Scale (NIHSS) score ≥8, stroke symptom duration ≤8 h, premorbid modified Rankin Scale (mRS) score ≤2, and thrombolysis myocardial infarction score 2-3. We analyzed the relationships of ORT, THRIVE score, and THRIVE+ORT score with good outcome (mRS ≤2 at 3 months). The THRIVE+ORT score was defined as the sum of the THRIVE score and ORT (h). Results: Median ORT was 5.5 h (IQR; 4.4-7.1 h), median THRIVE score was 5 (IQR; 4-6), and median THRIVE+ORT score was 10.8 (IQR; 9.2-12.5). Good outcome rates for patients with ORT ≤4 h, >4 and ≤6 h, >6 and ≤8 h, and >8h were 50.0%, 45.8%, 37.0%, and 21.4%, respectively (p=0.3), those with THRIVE score ≤3, >3 and ≤5, >5 and ≤7, and >7 were 57.1%, 51.4%, 28.3%, and 20.0%, respectively (p9 and ≤11, >11 and ≤13, and >13 were 64.0%, 44.1%, 34.4%, and 16.7%, respectively (p Conclusion: Our study showed that THRIVE+ORT score was associated with outcome that was independent from THRIVE score or ORT. This is the first report to suggest that patients with the higher THRIVE score require the shorter ORT for good outcome.