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Background and Purpose In young patients (aged 18–60 years) with patent foramen ovale (PFO)-associated stroke, percutaneous closure has been found to be useful for preventing recurrent ischemic stroke or transient ischemic attack (TIA). However, it remains unknown whether PFO closure is also beneficial in older patients. Methods Patients aged ≥60 years who had a cryptogenic stroke and PFO from ten hospitals in South Korea were included. The effect of PFO closure plus medical therapy over medical therapy alone was assessed by a propensity-score matching method in the overall cohort and in those with a high-risk PFO, characterized by the presence of an atrial septal aneurysm or a large shunt. Results Out of the 437 patients (mean age, 68.1), 303 (69%) had a high-risk PFO and 161 (37%) patients underwent PFO closure. Over a median follow-up of 3.9 years, recurrent ischemic stroke or TIA developed in 64 (14.6%) patients. In the propensity score-matched cohort of the overall patients (130 pairs), PFO closure was associated with a significantly lower risk of a composite of ischemic stroke or TIA (hazard ratio [HR]: 0.45; 95% confidence interval [CI]: 0.24–0.84; P=0.012), but not for ischemic stroke. In a subgroup analysis of confined to the high-risk PFO patients (116 pairs), PFO closure was associated with significantly lower risks of both the composite of ischemic stroke or TIA (HR: 0.40; 95% CI: 0.21–0.77; P=0.006) and ischemic stroke (HR: 0.47; 95% CI: 0.23–0.95; P=0.035). Conclusion Elderly patients with cryptogenic stroke and PFO have a high recurrence rate of ischemic stroke or TIA, which may be significantly reduced by device closure.

Background and Purpose The accurate prediction of functional outcomes in patients with acute ischemic stroke (AIS) is crucial for informed clinical decision-making and optimal resource utilization. As such, this study aimed to construct an ensemble deep learning model that integrates multimodal imaging and clinical data to predict the 90-day functional outcomes after AIS. Methods We used data from the Korean Stroke Neuroimaging Initiative database, a prospective multicenter stroke registry to construct an ensemble model integrated individual 3D convolutional neural networks for diffusion-weighted imaging and fluid-attenuated inversion recovery (FLAIR), along with a deep neural network for clinical data, to predict 90-day functional independence after AIS using a modified Rankin Scale (mRS) of 3–6. To evaluate the performance of the ensemble model, we compared the area under the curve (AUC) of the proposed method with that of individual models trained on each modality to identify patients with AIS with an mRS score of 3–6. Results Of the 2,606 patients with AIS, 993 (38.1%) achieved an mRS score of 3–6 at 90 days post-stroke. Our model achieved AUC values of 0.830 (standard cross-validation [CV]) and 0.779 (time-based CV), which significantly outperformed the other models relying on single modalities: b-value of 1,000 s/mm2 (P

BackgroundAfter carotid artery angioplasty with stenting (CAS), it is unclear which risk factors are related to long-term outcomes, including in-stent restenosis (ISR). This study aimed to assess the factors associated with restenosis after CAS with a median follow-up of 35.7 months.Materials and methodsPatients who underwent CAS from January 2013 to December 2018 were included if they had symptomatic or asymptomatic carotid artery stenosis. The carotid Doppler ultrasonography (CDU) was followed up after the procedure. We defined at least 50% restenosis using the criteria that the internal carotid artery (ICA) peak systolic velocity (PSV) was greater than 224 cm/s or the ICA to common carotid artery PSV ratio was higher than 3.4. The risk factors for ISR were also assessed.ResultsOf the 189 patients, 122 had symptomatic carotid artery stenosis, and 67 had asymptomatic carotid artery stenosis. Patients were evaluated by CDU for a median of 35.7 months (interquartile range 19.5 to 70.0). Kaplan–Meier analysis showed that the longest time to ISR was 39 months, and ISR-free was better in the asymptomatic CAS group. In all groups, ISR was independently associated with current smoker [adjusted odds ratio (aOR), 3.425; 95% confidence interval (CI), 1.086 to 10.801] and elevated ICA PSV at baseline (aOR, 1.004; 95% CI, 1.001 to 1.007).ConclusionIndependent risk factors for ISR in the CAS group included current smoking and elevated ICA PSV at baseline. In the symptomatic CAS group, alcohol was independently associated with the ISR. ISR did not occur after 39 months from the CAS procedure in our study patients. Future studies with extended follow-up are necessary to fully understand the long-term outcomes of CAS.

Introduction: There is little evidence about the factors related to the detection of neurological deterioration by nurses. We examined the related factors and therapeutic outcomes of nurses' detections of patient's neurological deterioration. Methods: This was a descriptive retrospective study. We included 549 adult stroke patients who were admitted to the acute stroke unit of a tertiary hospital between May 2018 and December 2019 and had changes in neurological symptoms that were detected by stroke nurses. We measured the following outcomes: stroke lesion progression, early neurological deterioration (increase in the total national institutes of health stroke scale score of 2 points or more, increase in the limb weakness score of 1 point or more, or decrease in the alertness score of 1 point or more), and additional clinical management (increasing intravenous fluids, diagnostic imaging, or neuro-intervention). Data was analyzed by logistic regression. Results: A total of 651 new or aggravating symptoms were detected by nurses. The most detected symptom was motor aggravations (49.2 %). Symptoms were commonly detected during the day shift (51.0 %) and by scheduled neurochecks (71.3 %). Of 132 patients who underwent diagnostic imaging by nurses’ detection, 63.6 % cases had stroke lesion progression. Nursing experience over 4 years was positively associated with finding stroke lesion progression (OR: 2.49, 95 % CI = 1.09–5.67). Early neurological deterioration was found in 70.7 %, and it was significantly higher during scheduled neurochecks (OR:2.65, 95 % CI = 1.04–6.72) and in the group of large artery atherosclerosis (OR: 2.19, 95 % CI = 1.06–4.49) Additional clinical management was provided to 49.9 % of detection, and scheduled neurocheks (OR: 4.76, 95 % CI = 2.18–10.39) and changes of alertness (OR: 2.89, 96 % CI = 1.51–5.26) were the significant factors. Conclusion: Stroke nurses were able to detect a large number of stroke lesion progression and early neurological deterioration as well as to provide additional clinical management. Systematic guidelines for qualification of stroke nurses may be beneficial.

Objectives Limited information is available concerning the epidemiology of stroke and acute myocardial infarction (AMI) in the Republic of Korea. This study aimed to develop a national surveillance system to monitor the incidence of stroke and AMI using national claims data. Methods We developed and validated identification algorithms for stroke and AMI using claims data. This validation involved a 2-stage stratified sampling method with a review of medical records for sampled cases. The weighted positive predictive value (PPV) and negative predictive value (NPV) were calculated based on the sampling structure and the corresponding sampling rates. Incident cases and the incidence rates of stroke and AMI in the Republic of Korea were estimated by applying the algorithms and weighted PPV and NPV to the 2018 National Health Insurance Service claims data. Results In total, 2,200 cases (1,086 stroke cases and 1,114 AMI cases) were sampled from the 2018 claims database. The sensitivity and specificity of the algorithms were 94.3% and 88.6% for stroke and 97.9% and 90.1% for AMI, respectively. The estimated number of cases, including recurrent events, was 150,837 for stroke and 40,529 for AMI in 2018. The age- and sex-standardized incidence rate for stroke and AMI was 180.2 and 46.1 cases per 100,000 person-years, respectively, in 2018. Conclusion This study demonstrates the feasibility of developing a national surveillance system based on claims data and identification algorithms for stroke and AMI to monitor their incidence rates.

Background and Purpose The additive effects of intravenous thrombolysis (IVT) before mechanical thrombectomy (MT) remain unclear. We aimed to investigate the efficacy and safety of IVT prior to MT depending on the location of M1 occlusion. Methods We reviewed the cases of patients who underwent MT for emergent large-vessel occlusion of the M1 segment. Baseline characteristics as well as clinical and periprocedural variables were compared according to the location of M1 occlusion (i.e., proximal and distal M1 occlusion). The main outcome was the achievement of functional independence (modified Rankin Scale score, 0–2) at 3 months after stroke. The main outcomes were compared between the proximal and distal groups based on the use of IVT before MT. Results Among 271 patients (proximal occlusion, 44.6%; distal occlusion, 55.4%), 33.9% (41/121) with proximal occlusion and 24.7% (37/150) with distal occlusion underwent IVT prior to MT. Large-artery atherosclerosis was more common in patients with proximal M1 occlusion; cardioembolism was more common in those with distal M1 occlusion. In patients with proximal M1 occlusion, there was no association between IVT before MT and functional independence. In contrast, there was a significant association between the use of IVT prior to MT (odds ratio=5.30, 95% confidence interval=1.56–18.05, P=0.007) and functional independence in patients with distal M1 occlusion. Conclusion IVT before MT was associated with improved functional outcomes in patients with M1 occlusion, especially in those with distal M1 occlusion but not in those with proximal M1 occlusion.

Abstract Early neurological deterioration (END) in lenticulostriate artery (LSA) infarction is associated with perforating artery hypoperfusion. As middle cerebral artery (MCA) tortuosity may alter hemodynamics, we investigated the association between MCA tortuosity and END in LSA infarction. We reviewed patients with acute LSA infarction without significant MCA stenosis. END was defined as an increase of ≥ 2 or ≥ 1 in the National Institutes of Health Stroke Scale (NIHSS) total or motor score, respectively, within first 72 h. The MCA tortuosity index (actual /straight length) was measured. Stroke mechanisms were categorized as branch atheromatous disease (BAD; lesions > 10 mm and 4 axial slices) and lipohyalinotic degeneration (LD; lesion smaller than BAD). Factors associated with END in LD and BAD were investigated. END occurred in 104/390 (26.7%) patients. A high MCA tortuosity index (adjusted odds ratio, aOR 10.63, 95% confidence interval [2.57–44.08], p = 0.001) was independently associated with END. In patients with BAD, high initial NIHSS score (aOR 1.40 [1.03–1.89], p = 0.031) and presence of parental artery disease (stenosis

Purpose To propose standardized and feasible imaging protocols for constructing artificial intelligence (AI) database in acute stroke by assessing the current practice at tertiary hospitals in South Korea and reviewing evolving AI models. Materials and Methods A nationwide survey on acute stroke imaging protocols was conducted using an electronic questionnaire sent to 43 registered tertiary hospitals between April and May 2021. Imaging protocols for endovascular thrombectomy (EVT) in the early and late time windows and during follow-up were assessed. Clinical applications of AI techniques in stroke imaging and required sequences for developing AI models were reviewed. Standardized and feasible imaging protocols for data curation in acute stroke were proposed. Results There was considerable heterogeneity in the imaging protocols for EVT candidates in the early and late time windows and posterior circulation stroke. Computed tomography (CT)-based protocols were adopted by 70% (30/43), and acquisition of noncontrast CT, CT angiography and CT perfusion in a single session was most commonly performed (47%, 14/30) with the preference of multiphase (70%, 21/30) over single phase CT angiography. More hospitals performed magnetic resonance imaging (MRI)-based protocols or additional MRI sequences in a late time window and posterior circulation stroke. Diffusion-weighted imaging (DWI) and fluid-attenuated inversion recovery (FLAIR) were most commonly performed MRI sequences with considerable variation in performing other MRI sequences. AI models for diagnostic purposes required noncontrast CT, CT angiography and DWI while FLAIR, dynamic susceptibility contrast perfusion, and T1-weighted imaging (T1WI) were additionally required for prognostic AI models. Conclusion Given considerable heterogeneity in acute stroke imaging protocols at tertiary hospitals in South Korea, standardized and feasible imaging protocols are required for constructing AI database in acute stroke. The essential sequences may be noncontrast CT, DWI, CT/MR angiography and CT/MR perfusion while FLAIR and T1WI may be additionally required.

Abstract Blood viscosity may affect the mechanisms of stroke and early neurological deterioration (END). We aimed to investigate the relationship between blood viscosity, stroke mechanisms, and END in patients with middle cerebral artery (MCA) infarction. Patients with symptomatic MCA atherosclerosis (≥ 50% stenosis) were recruited. Blood viscosity was compared across patients with different mechanisms of symptomatic MCA disease: in situ thrombo-occlusion (sMCA-IST), artery-to-artery embolism (sMCA-AAE), and local branch occlusion (sMCA-LBO). END was defined as four points increase in the National Institutes of Health Stroke Scale score from baseline during the first week. The association between blood viscosity and END was also evaluated. A total of 360 patients (76 with sMCA-IST, 216 with sMCA-AAE, and 68 with sMCA-LBO) were investigated. Blood viscosity was highest in patients with sMCA-IST, followed by sMCA-AAE and sMCA-LBO (P

Background and purposeAtrial fibrillation-related stroke (AF-stroke) is associated with an adverse prognosis, characterized by a high incidence of progression, recurrence, and hemorrhagic transformation. Our study aims to investigate the potential benefits of stratified early administration of apixaban, taking into account infarct size during the acute phase, in order to enhance functional outcomes.MethodsWe conducted this study at a tertiary referral stroke center, enrolling acute AF-stroke patients who received apixaban during the acute phase. Infarct size was categorized as small, medium, or large based on diffusion-weighted imaging. Patients were divided into two groups: standard initiation (apixaban initiation based on guidelines, i.e., small: 4 days, medium: 7 days, large: 14 days after stroke) and early initiation (initiation before guideline recommendations) groups. We compared favorable outcomes (modified Rankin scale score ≤ 2) at 3 months post-stroke, stroke progression, early recurrence, and symptomatic hemorrhagic transformation (sHT) between the groups.ResultsOut of 299 AF-stroke patients, 170 (56.9%) were in the early initiation group. A favorable outcome was observed in 105 (61.8%) patients in the early initiation group and 62 (48.1%) patients in the standard initiation group (p = 0.019). Stroke progression or early recurrence occurred less frequently in the early initiation group (4.7% versus 13.2%, p = 0.007). Nevertheless, no difference in sHT was noted between the groups. Early initiation of apixaban was independently associated with favorable outcomes (odds ratio: 2.75, 95% confidence interval: 1.44–5.28, p = 0.002).ConclusionOur findings suggest that early initiation of apixaban, tailored to infarct size, could serve as a viable strategy to enhance functional outcomes. This approach may potentially decrease stroke progression and early recurrence without elevating the risk of sHT.

Background Vascular tortuosity affects the outcomes of mechanical thrombectomy (MT). We classified vertebral artery (VA) tortuosity into 3 types and investigated the effect of VA tortuosity on the outcomes in patients with basilar artery occlusion. Methods We retrospectively included patients who underwent MT for basilar artery occlusion between January 2012 and May 2022. Clinical and procedure‐related factors were obtained. VA tortuosity was classified into 3 types: type I: nontortuous VA; type II: S‐shaped vessel or a VA with a single acute angulation (1 location. The 3‐month modified Rankin scale, procedural outcomes, and post‐MT intracranial hemorrhage were assessed. Results A total of 106 patients with basilar artery occlusion were included. Age, baseline stroke severity, and 3‐month modified Rankin scale score were significantly different according to VA tortuosity (P = 0.003, P = 0.002, and P

BackgroundVideo head impulse tests (vHITs), assessing the vestibulo-ocular reflex (VOR), may be helpful in the differential diagnosis of acute dizziness. We aimed to investigate vHITs in patients with acute posterior circulation stroke (PCS) to examine whether these findings could exhibit significant abnormalities based on lesion locations, and to evaluate diagnostic value of vHIT in differentiating dizziness between PCS and vestibular neuritis (VN).MethodsWe prospectively recruited consecutive 80 patients with acute PCS and analyzed vHIT findings according to the presence of dorsal brainstem stroke (DBS). We also compared vHIT findings between PCS patients with dizziness and a previously studied VN group (n = 29). Receiver operating characteristic (ROC) analysis was performed to assess the performance of VOR gain and its asymmetry in distinguishing dizziness between PCS and VN.ResultsPatients with PCS underwent vHIT within a median of 2 days from stroke onset. Mean horizontal VOR gain was 0.97, and there was no significant difference between PCS patients with DBS (n = 15) and without (n = 65). None exhibited pathologic overt corrective saccades. When comparing the PCS group with dizziness (n = 40) to the VN group (n = 29), patients with VN demonstrated significantly lower mean VOR gains in the ipsilesional horizontal canals (1.00 vs. 0.57, p

Background Approximately 10% of patients with acute ischemic stroke with large‐vessel occlusion (LVO) have mild neurological deficits. Although leptomeningeal collaterals (LMCs) are the major determinant of clinical outcomes for patients with acute ischemic stroke with LVO, the contribution of baseline LMC status to subsequent infarct progression in patients with mild stroke with LVO is poorly defined. Methods This observational study included patients with acute anterior circulation LVO and mild stroke symptoms (National Institutes of Health Stroke Scale < 6) from a prospectively collected, multicenter, national stroke registry. The Alberta Stroke Program Early Computed Tomography Score was quantified on the initial and follow‐up images. An infarct progression, defined as any Alberta Stroke Program Early Computed Tomography Score decrease between the initial versus follow‐up scans, was categorized as either 0/1/2+. The LMCs on the baseline images were graded as good, fair, or poor. Results Of the 623 included patients (mean age, 67.6±13.4 years; 380 [61.0%] men; 186 [29.9%] with reperfusion treatment), the baseline LMC was graded as good in 331 (53.1%), fair in 219 (35.2%), and poor in 73 (11.7%). The Alberta Stroke Program Early Computed Tomography Score decrement was noted as 0 in 288 (46%) patients, 1 in 154 (24%), and 2+ in 181 (29%). A poor LMC was associated with an infarct progression (adjusted odds ratio, 2.05 [95% CI, 1.22–3.47]). Conclusions Poor collateral blood flow was associated with infarct progression in patients with acute ischemic stroke with LVO and mild symptoms. In this selective population, early assessment of collateral blood flow status can help in early detection of patients susceptible to infarct progression.

Abstract Background Prognosis after vertebrobasilar stenting (VBS) may differ from that after carotid artery stenting (CAS). Here, we directly compared the incidence and predictors of in-stent restenosis and stented-territory infarction after VBS and compared them with those of CAS. Methods We enrolled patients who underwent VBS or CAS. Clinical variables and procedure-related factors were obtained. During the 3 years of follow-up, in-stent restenosis and infarction were investigated in each group. In-stent restenosis was defined as reduction in the lumen diameter > 50% compared with that after stenting. Factors associated with the occurrence of in-stent restenosis and stented-territory infarction in VBS and CAS were compared. Results Among 417 stent insertions (93 VBS and 324 CAS), there was no statistical difference in in-stent restenosis between VBS and CAS (12.9% vs. 6.8%, P = 0.092). However, stented-territory infarction was more frequently observed in VBS than in CAS (22.6% vs. 10.8%; P = 0.006), especially a month after stent insertion. HbA1c level, clopidogrel resistance, and multiple stents in VBS and young age in CAS increased the risk of in-stent restenosis. Diabetes (3.82 [1.24–11.7]) and multiple stents (22.4 [2.4–206.4]) were associated with stented-territory infarction in VBS. However, in-stent restenosis (odds ratio: 15.1, 95% confidence interval: 3.17–72.2) was associated with stented-territory infarction in CAS. Conclusions Stented-territory infarction occurred more frequently in VBS, especially after the periprocedural period. In-stent restenosis was associated with stented-territory infarction after CAS, but not in VBS. The mechanism of stented-territory infarction after VBS may be different from that after CAS.

Background and Purpose Various mechanisms are involved in the etiology of stroke caused by atherosclerosis of the middle cerebral artery (MCA). Here, we compared differences in plaque nature and hemodynamic parameters according to stroke mechanism in patients with MCA atherosclerosis. Methods Consecutive patients with asymptomatic and symptomatic MCA atherosclerosis (≥50% stenosis) were enrolled. MCA plaque characteristics (location and plaque enhancement) and wall shear stress (WSS) were measured using high-resolution vessel wall and four-dimensional flow magnetic resonance imaging, respectively, at five points (initial, upstream, minimal lumen, downstream, and terminal). These parameters were compared between patients with asymptomatic and symptomatic MCA atherosclerosis with infarctions of different mechanisms (artery-to-artery embolism vs. local branch occlusion). Results In total, 110 patients (46 asymptomatic, 32 artery-to-artery embolisms, and 32 local branch occlusions) were investigated. Plaques were evenly distributed in the MCA of patients with asymptomatic MCA atherosclerosis, more commonly observed in the distal MCA of patients with artery-to-artery embolism, and in the middle MCA of patients with local branch occlusion. Maximum WSS and plaque enhancement were more prominent in the minimum lumen area of patients with asymptomatic MCA atherosclerosis or those with local branch occlusion, and were more prominent in the upstream area in those with artery-to-artery embolism. The elevated variability in the maximum WSS was related to stroke caused by artery-to-artery embolism. Conclusion Stroke caused by artery-to-artery embolism was related to plaque enhancement and the highest maximum WSS at the upstream point of the plaque, and was associated with elevated variability of maximum WSS.

Background There are no clear data to support the cardiovascular (CV) risk categories and low-density lipoprotein cholesterol (LDL-C) treatment goals in Korean people with type 2 diabetes mellitus (T2DM). We evaluated the incidence of cardiovascular disease (CVD) according to comorbidities and suggested LDL-C treatment goals in Korean people with T2DM in nationwide cohort data. Methods Using the Korean National Health Insurance Service database, 248,002 people aged 30 to 90 years with T2DM who underwent routine health check-ups during 2009 were included. Subjects with previous CVD were excluded from the study. The primary outcome was incident CVD, defined as a composite of myocardial infarction and ischemic stroke during the follow-up period from 2009 to 2018. Results The mean age of the study participants was 59.6±10.9 years, and median follow-up period was 9.3 years. CVD incidence increased in the order of DM duration of 5 years or more (12.04/1,000 person-years), hypertension (HT) (12.27/1,000 personyears), three or more CV risk factors (14.10/1,000 person-years), and chronic kidney disease (18.28/1,000 person-years). The risk of incident CVD increased linearly from an LDL-C level of ≥70 mg/dL in most patients with T2DM. In T2DM patients without HT or with a DM duration of less than 5 years, the CVD incidence increased from LDL-C level of ≥100 mg/dL. Conclusion For primary prevention of CVD in Korean adults with T2DM, it can be helpful to lower LDL-C targets when there are chronic kidney disease, HT, a long duration of diabetes mellitus, or three or more CV risk factors.

Background To validate the treatment target of low-density lipoprotein cholesterol (LDL-C) level according to the cardiovascular disease (CVD) risk which was recommended by Korean dyslipidemia guideline. Methods We used the Korean National Health Insurance Service database which included 3,958,048 people aged 20 to 89 years who underwent regular health screening. The primary outcome was incident CVD, defined as a composite of myocardial infarction and stroke during the follow-up period from 2009 to 2018. Results The risk of CVD increased from LDL-C level of 70 mg/dL in very high-risk and high-risk groups and from 130 mg/dL in moderate-risk and low-risk groups. Adjusted hazard ratios (HRs) of LDL-C ranges 70–99, 100–129, 130–159, 160–189, and ≥190 mg/dL were 1.20 (95% confidence interval [CI], 1.08–1.33), 1.27 (1.15–1.42), 1.39 (1.23–1.56), 1.69 (1.45–1.96), and 1.84 (1.49– 2.27) in very high-risk group, and 1.07 (1.02–1.13), 1.16 (1.10–1.21), 1.29 (1.22–1.36), 1.45 (1.36–1.55), and 1.73 (1.58–1.90) in high-risk group. Adjusted HRs (95% CI) of LDL-C ranges 130–159, 160–189, and ≥190 mg/dL were 1.15 (1.11–1.20), 1.28 (1.22– 1.34), and 1.45 (1.36–1.54) in moderate-risk group and 1.07 (1.02–1.13), 1.20 (1.13–1.26), and 1.47 (1.37–1.57) in low-risk group. Conclusion We confirmed the incidence of CVD was increased in higher LDL-C range. The risk of CVD increased from ≥70 mg/dL of LDL-C in very high-risk and high-risk groups, and from ≥130 mg/dL of LDL-C in moderate-risk and low-risk groups in Korean adults.

Abstract Two different stroke mechanisms are involved in small vessel disease: branch atheromatous disease (BAD) and lipohyalinotic degeneration (LD). We compared mechanisms of stroke in lenticulostriate arteries (LSA) vs. anterior pontine arteries (APA) and verified factors associated with stroke mechanisms, including shape of middle cerebral artery (MCA) and basilar artery (BA). We retrospectively reviewed patients with acute ischemic stroke with penetrating artery territory confirmed by MRI. The mechanisms of stroke were categorized based on diffusion-weighted imaging; BAD was defined as lesion larger than 10 mm in LSA and lesions involving basal pontine in APA. Other lesions were classified as LD. The shapes of MCA and BA were classified as straight, with one angle, or with two angles (U, C or S shape, respectively) using anterior–posterior view. The study included 221 patients. LD was more common in LSA infarcts, but BAD was more common in APA infarcts (p

Background and purposeTop-of-basilar artery occlusion (TOB) is one of the most devastating strokes despite successful mechanical thrombectomy (MT). We aimed to investigate the impact of initial low cerebellum perfusion delay on the outcomes of TOB treated with MT.MethodsWe included patients who underwent MT for TOB. Clinical and peri-procedural variables were obtained. Perfusion delay in the low cerebellum was defined as (1) time-to-maximum (Tmax) >10 s lesions or (2) relative time-to-peak (rTTP) map >9.5 s with a diameter of ≥6 mm in the low cerebellum. The good functional outcome was defined as the achievement of a modified Rankin Scale score of 0–3 at 3 months after stroke.ResultsAmong the 42 included patients, 24 (57.1%) patients showed perfusion delay in the low cerebellum. The admission National Institutes of Health Stroke Scale (NIHSS) score was significantly higher in those with perfusion delay [17 (12–24) vs. 8 (6–15), P = 0.002]. Accordingly, the proportion of good functional outcomes was lower in those with perfusion delay than in those without [5 (20.8%) vs. 13 (72.2%), P = 0.003]. From the multivariable analysis, the admission NIHSS score [odds ratio (OR) = 0.86, 95% confidence intervals (CIs) = 0.75–0.98, P = 0.021] and low cerebellum perfusion delay (OR = 0.18, 95% Cis = 0.04–0.86, P = 0.031) were independently associated with the 3-month functional outcomes.ConclusionWe found that initial perfusion delay proximal to TOB in the low cerebellum might be a predictor for poor functional outcomes in TOB treated with MT.

BackgroundThe mechanism and characteristics of a post-transplantation stroke may differ between liver (LT) and kidney transplantation (KT), as the associated comorbidities and peri-surgical conditions are different. Herein, we investigated the characteristics and etiologies of stroke occurring after LT and KT.MethodsConsecutive patients who received LT or KT between January 2005 to December 2020 who were diagnosed with ischemic or hemorrhagic stroke after transplantation were enrolled. Ischemic strokes were further classified according to the etiologies. The characteristics of stroke, including in-hospital stroke, perioperative stroke, stroke etiology, and timing of stroke, were compared between the LT and KT groups.ResultsThere were 105 (1.8%) and 58 (1.3%) post-transplantation stroke patients in 5,950 LT and 4,475 KT recipients, respectively. Diabetes, hypertension, and coronary arterial disease were less frequent in the LT than the KT group. In-hospital and perioperative strokes were more common in LT than in the KT group (LT, 57.9%; KT, 39.7%; p = 0.03, and LT, 43.9%; KT, 27.6%; p = 0.04, respectively). Hemorrhagic strokes were also more common in the LT group (LT, 25.2%; KT, 8.6%; p = 0.01). Analysis of ischemic stroke etiology did not reveal significant difference between the two groups; undetermined etiology was the most common, followed by small vessel occlusion and cardioembolism. The 3-month mortality was similar between the two groups (both LT and KT, 10.3%) and was independently associated with in-hospital stroke and elevated C-reactive protein.ConclusionsIn-hospital, perioperative, and hemorrhagic strokes were more common in the LT group than in the KT group. Ischemic stroke subtypes did not differ significantly between the two groups and undetermined etiology was the most common cause of ischemic stroke in both groups. High mortality after stroke was noted in transplantation patients and was associated with in-hospital stroke.

Abstract We aimed to develop a novel prediction model for early neurological deterioration (END) based on an interpretable machine learning (ML) algorithm for atrial fibrillation (AF)-related stroke and to evaluate the prediction accuracy and feature importance of ML models. Data from multicenter prospective stroke registries in South Korea were collected. After stepwise data preprocessing, we utilized logistic regression, support vector machine, extreme gradient boosting, light gradient boosting machine (LightGBM), and multilayer perceptron models. We used the Shapley additive explanation (SHAP) method to evaluate feature importance. Of the 3,213 stroke patients, the 2,363 who had arrived at the hospital within 24 h of symptom onset and had available information regarding END were included. Of these, 318 (13.5%) had END. The LightGBM model showed the highest area under the receiver operating characteristic curve (0.772; 95% confidence interval, 0.715–0.829). The feature importance analysis revealed that fasting glucose level and the National Institute of Health Stroke Scale score were the most influential factors. Among ML algorithms, the LightGBM model was particularly useful for predicting END, as it revealed new and diverse predictors. Additionally, the effects of the features on the predictive power of the model were individualized using the SHAP method.

Introduction: False memory, observed as intrusion errors or false positives (FPs), is prevalent in patients with Alzheimer’s disease, but has yet to be thoroughly investigated in patients with amnestic mild cognitive impairment (a-MCI) with Alzheimer’s disease pathology (ADP). We analyzed false versus veridical memory in individuals with a-MCI and measured the utility of false memory for ADP discrimination. Methods: Patients with a-MCI who received neuropsychological testing and amyloid PET were included. Patients were categorized into “with” and “without ADP” groups according to PET results. Memory tests assessed veridical and false memory, and the verity of patient responses was analyzed. A logistic regression model was used to evaluate false memory efficiency in discriminating ADP, and the sensitivity and specificity at the optimal level were estimated using the receiver-operating characteristic curve. Results: Thirty-seven ADP and 46 non-ADP patients were enrolled. The ADP group made more FPs in the recognition tests, and their response verity was significantly lower in every delayed memory test. No group difference, however, was observed in the veridical memory. The logistic regression analysis demonstrated that as the FPs increased, the risk of ADP increased 1.31 and 1.36 times in the verbal and visual recognition tests, respectively. The discriminatory accuracy of the FPs was estimated “low” to “moderate” in the visual and verbal recognition, respectively, with an optimal cutoff above 2.5. Conclusion: Increased false memory was the only feature to discriminate ADP from non-ADP in individuals with a-MCI. Further studies regarding false memory and its mechanism are warranted.

Background and purposeThere is much uncertainty in endovascular treatment (EVT) decisions in patients with acute large vessel occlusion (LVO) and mild neurological deficits.MethodsFrom a prospective, nationwide stroke registry, all patients with LVO and baseline NIHSS

BackgroundStudies of secondary movement disorder (MD) caused by cerebrovascular diseases have primarily focused on post-stroke MD. However, MD can also result from cerebral artery stenosis (CAS) without clinical manifestations of stroke. In this study, we aimed to investigate the clinical characteristics of MD associated with CAS.Materials and MethodsA nationwide multicenter retrospective analysis was performed based on the data from patients with CAS-associated MDs from 16 MD specialized clinics in South Korea, available between January 1999 and September 2019. CAS was defined as the >50% luminal stenosis of the major cerebral arteries. The association between MD and CAS was determined by MD specialists using pre-defined clinical criteria. The collected clinical information included baseline demographics, features of MD, characteristics of CAS, treatment, and MD outcomes. Statistical analyses were performed to identify factors associated with the MD outcomes.ResultsThe data from a total of 81 patients with CAS-associated MD were analyzed. The mean age of MD onset was 60.5 ± 19.7 years. Chorea was the most common MD (57%), followed by tremor/limb-shaking, myoclonus, and dystonia. Atherosclerosis was the most common etiology of CAS (78%), with the remaining cases attributed to moyamoya disease (MMD). Relative to patients with atherosclerosis, those with MMD developed MD at a younger age (p < 0.001) and had a more chronic mode of onset (p = 0.001) and less acute ischemic lesion (p = 0.021). Eight patients who underwent surgical treatment for CAS showed positive outcomes. Patients with acute MD onset had a better outcome than those with subacute-to-chronic MD onset (p = 0.008).ConclusionsThis study highlights the spectrum of CAS-associated with MD across the country. A progressive, age-dependent functional neuronal modulation in the basal ganglia due to CAS may underlie this condition.

Hypertension is a major, yet manageable, risk factor for stroke, and the benefits of well-controlled blood pressure are well established. However, the strategy for managing blood pressure can differ based on the pathomechanism (subtype), stage, and treatment of stroke patients. In the present review, we focused on the management of blood pressure during the acute stage of intracerebral hemorrhage, subarachnoid hemorrhage, and cerebral infarction. In patients with cerebral infarction, the target blood pressure was discussed both before and after thrombolysis or other endovascular treatment, which may be an important issue. When and how to start antihypertensive medications during the acute ischemic stroke period were also discussed. In regards to the secondary prevention of ischemic stroke, the target blood pressure may differ based on the mechanism of ischemic stroke. We have reviewed previous studies and guidelines to summarize blood pressure management in various situations involving stroke patients.

Background Unlike patients with stroke caused by other mechanisms, the effect of elevated plasma total homocysteine (tHcy) on the prognosis of patients with both ischemic stroke and atrial fibrillation (AF) is unknown. This study aimed to evaluate the association between tHcy level and the functional outcome of patients with AF‐related stroke. Methods and Results We included consecutive patients with AF‐related stroke between 2013 and 2015 from the registry of a real‐world prospective cohort from 11 large centers in South Korea. A 3‐month modified Rankin Scale score ≥3 was considered an unfavorable outcome. Since tHcy is strongly affected by renal function, we performed a subgroup analysis according to the presence of renal dysfunction. A total of 910 patients with AF‐related stroke were evaluated (mean age, 73 years; male sex, 56.0%). The mean tHcy level was 11.98±8.81 μmol/L. In multivariable analysis, the tHcy level (adjusted odds ratio, 1.04; 95% CI, 1.01–1.07, per 1 μmol/L) remained significantly associated with unfavorable outcomes. In the subgroup analysis based on renal function, tHcy values above the cutoff point (≥14.60 μmol/L) showed a close association with the unfavorable outcome only in the normal renal function group (adjusted odds ratio, 3.10; 95% CI, 1.60–6.01). In patients with renal dysfunction, tHcy was not significantly associated with the prognosis of AF‐related stroke. Conclusions A higher plasma tHcy level was associated with unfavorable outcomes in patients with AF‐related stroke. This positive association may vary according to renal function but needs to be verified in further studies.

Abstract Background Atherosclerosis of the internal carotid artery (ICA) is an important cause of ischemic stroke. Artery-to-artery embolism is the major stroke mechanism in patients with atherosclerotic carotid disease. This study hypothesized that the atherosclerotic ICA geometry and plaque location would be associated with lesion pattern in patients with acute ischemic stroke. Methods Ischemic stroke patients with symptomatic proximal ICA disease (> 50% diameter stenosis) were enrolled. The carotid plaque location was divided into high-apical and low-body types. The geometric parameters of the ICA (angles between arteries) were measured, and ischemic lesion patterns were classified according to the number, location, and size of the lesions. Factors associated with plaque location and lesion pattern, dichotomized by size, were investigated. Results Of the 93 acute ischemic stroke patients enrolled, 31 had high-apical and 62 had low-body plaques. Hyperlipidemia was more prevalent and the common carotid artery (CCA)-ICA angle was wider (167.7 ± 10.4° vs 162.3 ± 9.8°, p = 0.019) in patients with low-body than high-apical plaques. Low-body plaques were more frequently associated with small scattered or cortical lesions (54.8% vs. 32.3%, p = 0.040), whereas high-apical plaques were more frequently associated with large lesions having additional lesions (38.7% vs. 11.3%, p = 0.002). The presence of low-body plaques (odds ratio: 3.106, 95% confidence interval: 1.105–8.728, p = 0.032) was independently associated with the small lesion-only pattern. Conclusions Low-body plaques are more frequently associated with small scattered lesions, whereas high-apical plaques are more frequently associated with large lesions having additional lesions. A wide CCA-ICA angle is associated with low-body plaque of the carotid artery.

Abstract Background Deep vein thrombosis (DVT) is an important complication of ischemic stroke, although the incidence of DVT is regarded as being lower in Asian than in non-Asian patients. Here, we investigated the incidence and factors associated with DVT in Asian patients with ischemic stroke. Methods Acute ischemic stroke patients received lower extremity ultrasonography (LEUS) to diagnose the presence of DVT. Clinical characteristics and laboratory results, including D-dimer level, were compared between patients with and without DVT. Independent risk factors for DVT were investigated using multivariable analysis. Similar analysis was performed to identify factors associated with elevated D-dimer level (> 0.5 mg/dl) in acute ischemic stroke patients. Results During the study period, 289 patients were enrolled, and 38 (13.1%) showed DVT. Female sex (OR = 2.579, 95% CI = 1.224–5.432; p = 0.013) and a high National Institutes of Health Stroke Scale (NIHSS) score (OR = 1.191 95% CI = 1.095–1.294; p = 0.005) were independently associated with the presence of DVT, although D-dimer level was not. Stroke mechanism, especially cardioembolic stroke (OR = 3.777, 95% CI = 1.532–9.313; p = 0.004; reference: large artery atherosclerosis), NIHSS score (OR = 1.087, 95% CI = 1.002–1.179; p = 0.001) and thrombolysis (OR = 12.360, 95% CI 2.456–62.213; p = 0.002) were independently associated with elevated abnormal D-dimer levels. Conclusion The severity of ischemic stroke, but not the D-dimer level, was associated with the presence of DVT in Asian ischemic stroke patients. D-dimer level was influenced by the stroke mechanism. LEUS in patients with severe neurological deficit, rather than screening with D-dimer, may be more beneficial for diagnosing DVT in Asian patients with acute ischemic stroke.

Background and Purpose The outcome of endovascular treatment (EVT) may differ depending on the etiology of arterial occlusion. This study aimed to assess the differences in EVT outcomes in patients with intracranial arterial steno-occlusion (ICAS-O), artery-to-artery embolism (AT-O), and cardiac embolism (CA-O). Methods We retrospectively analyzed 330 patients with ischemic stroke who underwent EVT between January 2012 and August 2017. Patients were classified according to the etiology. The clinical data, EVT-related factors, and clinical outcomes were compared. The modified Rankin Scale (mRS) score at 3 months, determined using ordinal logistic regression (shift analysis), was the primary outcome. Results CA-O (n=149) was the most common etiology, followed by ICAS-O (n=63) and AT-O (n=49). Age, initial National Institutes of Health Stroke Scale (NIHSS) score, and rate of hemorrhagic transformation were significantly higher in patients with CA-O compared to AT-O and ICAS-O. The time from onset-to-recanalization was the shortest in the CA-O (356.0 minutes) groups, followed by the AT-O (847.0 minutes) and ICAS-O (944.0 minutes) groups. The rates of successful recanalization, mRS distribution, and favorable outcomes at 3 months (mRS 0–2; CA-O, 36.9%, AT-O, 53.1%; and ICAS-O, 41.3%) did not differ among the three groups. Baseline NIHSS score (odds ratio, 0.87; 95% confidence interval, 0.83 to 0.91) could independently predict a favorable shift in mRS distribution. Conclusions The functional outcomes of ICAS-O and AT-O were similar to those of CA-O, despite the delay in symptom onset-to-recanalization, suggesting that the therapeutic time window may be extended in these patients.

ObjectiveChronic kidney disease (CKD) increases blood pressure variability (BPV) and affects stroke outcomes. However, the effect of BPV on early neurological deterioration (END) may be different according to the renal function.MethodsWe enrolled ischemic stroke patients with a National Institutes of Health Stroke Scale of ≤5. END was defined as worsening of ≥1 point in motor power or ≥2 points in total score. BPV was calculated with BP measured during the first 5 days and presented as standard deviation (SD) and coefficient of variation (CoV). Renal function was classified using the Kidney Disease Improving Global Outcomes (KDIGO) classification of CKD. Variables were compared between those with (KDIGO classification: moderate- to very-high-risk) and without renal impairment (KDIGO classification: low-risk) and factors associated with END were investigated.ResultsAmong the 290 patients (136 [46.9%] renal impairment), END was observed in 59 (20.3%) patients. BPV parameters and the risk of END increased as renal function was impaired. Renal function and systolic BP (SBP) mean, SD, CoV, and diastolic BP (DBP) mean, SD were independently associated with END. We found no association between BPV parameters and END in normal renal function patients; however, among impaired renal function patients, SBP SD (odds ratio [OR]: 1.20, 95% confidence interval [CI]: 1.09-1.32, PConclusionsThe association between END and BPV parameters differs according to renal function in minor ischemic stroke; BPV was associated with END in patients with renal impairment, but less in those with normal renal function.

Background: Ischemic stroke with atrial fibrillation (AF) may recur despite appropriate treatment. It may be AF-related or AF-unrelated. We compared the factors associated with AF-related and AF-unrelated recurrences among ischemic stroke patients with AF.Methods: Patients with ischemic stroke and AF were enrolled from 11 centers in Korea. Ischemic stroke recurrence was classified as AF-related if the lesion pattern was compatible with cardioembolism without significant stenosis or as AF-unrelated if the lesion was more likely due to small vessel disease or arterial stenosis. Factors associated with stroke recurrence (AF-related and AF-unrelated) were investigated.Results: Among the 2,239 patients, 115 (5.1%) experienced recurrence (75 AF-related and 40 AF-unrelated). Factors independently associated with any stroke recurrence included AF diagnosed before stroke, small subcortical infarctions, and small scattered lesions in a single vascular territory. Type of AF was associated with the type of stroke recurrence, with persistent AF being associated with AF-related stroke [hazard ratio (HR) = 2.94, 95% confidence interval (CI) 1.69–5.26; p < 0.001]. By contrast, paroxysmal AF (HR = 3.76, 95% CI 1.56–9.04; p = 0.003), AF diagnosed before stroke (HR = 2.38, 95% CI 1.19–4.55; p = 0.014), small scattered lesions in a single vascular territory (reference: corticosubcortical lesion, HR = 3.19, 95% CI 1.18–8.63; p = 0.022), and the use of antiplatelet agents (HR = 2.11, 95% CI 1.11–4.03; p = 0.024) were independently associated with AF-unrelated stroke.Conclusion: Persistent AF was more associated with AF-related stroke recurrence, whereas paroxysmal AF was more associated with AF-unrelated stroke recurrence. A scattered lesion in a single vascular territory may predict AF-unrelated stroke recurrence.

Background: The factors associated with clopidogrel resistance in patients with stroke recurrence receiving single or dual antiplatelet treatment (SAPT or DAPT) may differ. This study compared the high on-treatment platelet reactivities (HPRs) and the factors associated with clopidogrel resistance in recurrent ischemic stroke patients receiving clopidogrel or aspirin and clopidogrel.Methods: We enrolled and allocated 275 recurrent ischemic stroke patients to the clopidogrel and DAPT groups and compared their demographics, conventional risk factors, and P2Y12 reaction units (PRUs). Clopidogrel resistance was categorized as PRU higher than 275. We performed a multivariate logistic regression analysis to determine the factors underlying clopidogrel resistance during SAPT and DAPT.Results: In total, 145 (52.7%) and 130 (47.3%) patients received clopidogrel and DAPT, respectively at recurrence. The risk factors of the two groups were not significantly different, except that coronary artery disease was more frequent in the DAPT group. The PRU was higher (255 ± 91 vs. 221 ± 84; p = 0.002) and clopidogrel resistance was more frequent (45.5 vs. 31.5%; p = 0.018) in the SAPT than in the DAPT group. Hyperlipidemia was associated with clopidogrel resistance during SAPT, and smoking (Odds ratio = 0.426, 95% confidence interval 0.210–0.861; p = 0.018) had a protective effect against clopidogrel resistance. For those receiving DAPT, old age, female, low hemoglobin A1c level, and high ARU were associated with clopidogrel resistance.Conclusions: HPR and clopidogrel resistance were more frequent in recurrent ischemic stroke patients receiving clopidogrel than in those receiving DAPT. Smoking was independently associated with less clopidogrel resistance among those receiving clopidogrel SAPT but not in those receiving DAPT.

Background: Acute dizziness is a common symptom among patients visiting emergency medical centers. Extensive neurological examinations aimed at delineating the cause of dizziness often require experience and specialized training. We tried to diagnose central dizziness by machine learning using only basic clinical information.Methods: Patients were enrolled who had visited an emergency medical center with acute dizziness and underwent diffusion-weighted imaging. The enrolled patients were dichotomized as either having central (with a corresponding central lesion) or non-central dizziness. We obtained patient demographics, risk factors, vital signs, and presentation (non-whirling type dizziness or vertigo). Various machine learning algorithms were used to predict central dizziness. The area under the receiver operating characteristic curve (AUROC) was measured to evaluate diagnostic accuracy. The SHapley Additive exPlanations (SHAP) value was used to explain the importance of each factor.Results: Of the 4,481 visits, 414 (9.2%) were determined as central dizziness. Central dizziness patients were more often older and male and had more risk factors and higher systolic blood pressure. They also presented more frequently with non-whirling type dizziness (79 vs. 54.4%) than non-central dizziness. Catboost model showed the highest AUROC (0.738) with a 94.4% sensitivity and 31.9% specificity in the test set (n = 1,317). The SHAP value was highest for previous stroke presence (mean; 0.74), followed by male (0.33), presentation as non-whirling type dizziness (0.30), and age (0.25).Conclusions: Machine learning is feasible for classifying central dizziness using demographics, risk factors, vital signs, and clinical dizziness presentation, which are obtainable at the triage.

Purpose Cigarette smoking (CS) is one of the major risk factors of cerebral atherosclerotic disease, however, its level of contribution to extracranial and intracranial atherosclerotic stenosis (ECAS and ICAS) was not fully revealed yet. The purpose of our study was to assess the association of CS to cerebral atherosclerosis along with other risk factors. Materials and Methods All consecutive patients who were angiographically confirmed with severe symptomatic cerebral atherosclerotic disease between January 2002 and December 2012 were included in this study. Multivariate logistic regression analyses were performed to identify risk factors for ECAS and ICAS. Thereafter, CS group were compared to non-CS group in the entire study population and in a propensity-score matched population with two different age-subgroups. Results Of 1709 enrolled patients, 794 (46.5%) had extracranial (EC) lesions and the other 915 (53.5%) had intracranial (IC) lesions. CS group had more EC lesions (55.8% vs. 35.3%, P

Background There is insufficient evidence on the effect of statins, particularly high‐intensity statins, in patients with acute ischemic stroke and atrial fibrillation. We investigated the impact of statins on the outcomes in these patients, including those who might be vulnerable to statin therapy and those without clinical atherosclerotic cardiovascular diseases. Methods and Results A total of 2153 patients with acute ischemic stroke and atrial fibrillation were enrolled in the present nationwide, multicenter, cohort study. The primary composite end point was the occurrence of net adverse clinical and cerebral events (NACCE; death from any cause, stroke, acute coronary syndrome, or major bleeding) over a 3‐year period based on statin intensity. NACCE rates were lower in patients receiving low‐ to moderate‐intensity (adjusted hazard ratio 0.64; 95% CI: 0.52‐0.78) and high‐intensity statins (hazard ratio 0.51; 95% CI 0.40‐0.66) than in those not receiving statin therapy. High‐intensity statins were associated with a lower risk for NACCE than low‐ to moderate‐intensity statins (hazard ratio 0.76; 95% CI 0.59‐0.96). Subgroup analyses showed that the differences in hazard ratio for 3‐year NACCE favored statin use across all subgroups, including older patients, those with low cholesterol levels, patients receiving anticoagulants, and patients without clinical atherosclerotic cardiovascular diseases. Magnified benefits of high‐intensity statins compared with low‐ to moderate‐intensity statins were observed in patients who underwent revascularization therapy and those under 75 years of age. Conclusions Statins, particularly high‐intensity statins, could reduce the risk for NACCE in patients with acute ischemic stroke and atrial fibrillation; this needs to be further explored in randomized controlled trials.

Abstract Background Cervical artery dissection is one of the most important causes of ischemic stroke in young age patients. However, multiple cervical artery dissection simultaneously involving the anterior and posterior circulation is uncommon. Here, we would like to report a case of a patient with bilateral vertebral artery (VA) and internal carotid artery dissection (ICA) after a use of systemic steroid due to peripheral facial palsy. Case presentation A 44-year-old man with hypertension visited emergency department due to recurrent vertigo. He was receiving methyl prednisolone for two weeks for the treatment of right peripheral type facial palsy which occurred after retro-orbital headache. Neurologic examination revealed severe ataxia at left side. Sensory for pain and temperature was declined in the right arm and leg. Diffusion-weighted image showed an acute ischemic lesion at the whole territory of posterior-inferior cerebellar artery. Severe stenosis was observed from bilateral VAs and ICAs on conventional magnetic resonance angiography. Intramural hematoma and intimal flap was observed from the high-resolution MRI. Conclusions Peripheral type facial palsy is an unusual presentation of carotid dissection. Steroids aggravate arterial dissection by increasing blood pressure and blood vessel fragility by its negative effect on connective tissue strength. Use of steroid in patients with peripheral type facial palsy with severe headache may need caution.

Background and Purpose Subclinical atherosclerotic plaques are common in patients with pontine infarctions (PIs) but without basilar artery (BA) stenosis. We hypothesized that BA plaque locations may differ by PI type and vertical location as well as vertebrobasilar artery geometry. Methods Ninety-six patients with PI but without BA stenosis on magnetic resonance imaging (MRI) and magnetic resonance angiography were enrolled. PIs were classified by type (paramedian, deep, or lateral) and vertical location (rostral, middle, or caudal). Patients underwent high-resolution MRI to evaluate BA plaque location (anterior, posterior, or lateral). The mid-BA angle on anteroposterior view and angle between the BA and dominant vertebral artery (BA-VA angle) on lateral view were measured. Results The PIs were paramedian (72.9%), deep (17.7%), and lateral (9.4%) type with a rostral (32.3%), middle (42.7%), and caudal (25.0%) vertical location. The BA plaque locations differed by PI type (P=0.03) and vertical location (P

Background and Purpose Carotid plaques are a strong risk factor for ischemic stroke, and plaque rupture poses an even higher risk. Although many studies have investigated the pathogenic mechanisms of carotid plaque formation, few have studied the differences in molecular mechanisms underlying the rupture and non-rupture of carotid plaques. In addition, since early diagnosis and treatment of carotid plaque rupture are critical for the prevention of ischemic stroke, many studies have sought to identify the important target molecules involved in the rupture. However, a target molecule critical in symptomatic ruptured plaques is yet to be identified. Methods A total of 79 carotid plaques were consecutively collected, and microscopically divided into ruptured and non-ruptured groups. Quantitative polymerase chain reaction array, proteomics, and immunohistochemistry were performed to compare the differences in molecular mechanisms between ruptured and non-ruptured plaques. Enzyme-linked immunosorbent assay was used to measure the differences in ATP-binding cassette subfamily A member 1 (ABCA1) levels in the serum. Results The expression of several mRNAs and proteins, including ABCA1, was higher in ruptured plaques than non-ruptured plaques. In contrast, the expression of other proteins, including β-actin, was lower in ruptured plaques than non-ruptured plaques. The increased expression of ABCA1 was consistent across several experiments, ABCA1 was positive only in the serum of patients with symptomatic ruptured plaques. Conclusions This study introduces a plausible molecular mechanism underlying carotid plaque rupture, suggesting that ABCA1 plays a role in symptomatic rupture. Further study of ABCA1 is needed to confirm this hypothesis.

Background and Purpose Troponin, a marker of myocardial injury, frequently increases and is related with poor outcome in ischemic stroke patients. However, the long-term outcome of this elevation remains uncertain. We, therefore, investigated the prognostic significance of troponin elevation for long-term mortality, and explored factors affecting troponin elevation after ischemic stroke. Methods We retrospectively analyzed the medical data of stroke patients who were admitted within 24 hours of symptom onset and underwent a serum cardiac troponin I test at admission during a five-year period. Information on mortality as the outcome was obtained from the National Death Certificate system. Results A total of 1,692 patients were eligible for inclusion with 33 months of median follow-up. Troponin elevation that exceeded the 99th percentile (>0.04 ng/mL) of values was detected in 166 patients (9.8%). After adjusting for baseline characteristics, troponin elevation was associated with previous ischemic heart disease and congestive heart failure, comorbid atrial fibrillation and active cancer, and increased National Institutes of Health Stroke Scale score. Patients with troponin elevation had a high risk of overall death (hazard ratio [HR] 1.83, 95% confidence interval [CI] 1.40–2.40), including stroke-related (HR 1.71, 95% CI 1.14–2.55), cardiac-related (HR 3.17, 95% CI 1.49–6.74), and cancer-related (HR 1.98, 95% CI 1.14–3.45) death than those without troponin elevation. Conclusions Troponin elevation in the acute stage of ischemic stroke was associated with long-term mortality, mainly due to increased stroke- and cancer-related death in the first year and cardiacrelated death in the later period.

Background and aims: Atrial fibrillation (AF) is a major cause of ischemic stroke; however, detailed clinical data and prognostic factors for stroke patients with AF are lacking in Korea. We aimed to investigate clinical information and factors associated with functional outcomes of stroke patients with AF from the Korean nationwide ATrial fibrillaTion EvaluatioN regisTry in Ischemic strOke patieNts (K-ATTENTION) database.Methods: From January 2013 to December 2015, consecutive clinical information from acute stroke patients with AF or history of AF was collected from 11 centers in Korea. Collected data included demographics, risk factors, pre-stroke medication, stroke severity, stroke subtypes, concomitant cerebral atherosclerosis, brain image findings, recanalization therapy, discharge medication, and functional outcome at 3 months after index stroke.Results: A total of 3,213 stroke patients (mean age, 73.6 ± 9.8 years; female, 48.6%) were included. The mean CHA2DS2-VASc score was 4.9. Among the 1,849 (57.5%) patients who had brain image and functional outcome data, poor outcome (modified Rankin scale > 2) was noted in 53.1% (981/1,849) of patients. After adjusting for age, sex, and variables that had a p < 0.05 in univariate analysis or well-known factors for functional outcome, presence of asymptomatic extracranial cerebral atherosclerosis [odd ratio (OR): 1.96, 95% confidence interval (CI): 1.36–2.82, p = 0.001] and less frequent prior stroke statin intake (OR: 0.69, 95% CI: 0.49–0.98, p = 0.038) were associated with poor functional outcome.Conclusion: Our results suggest that presence of non-relevant extracranial cerebral atherosclerosis may affect poor functional outcome and prior stroke statin therapy may be feasible in Korean stroke patients with AF.

Background Evidence suggests that patients with higher blood pressure variability (BPV) have a higher risk for stroke, but any link between BPV and stroke recurrence is unknown among those who had a stroke or transient ischemic attack (TIA). Methods and Results Data for patients with a history of stroke or TIA at enrollment were extracted from the ASCOT (Anglo Scandinavian Cardiac Outcomes Trial) and the ALLHAT (Antihypertensive and Lipid‐Lowering Treatment to Prevent Heart Attack Trial). BPV was defined as the within‐subject standard deviation or coefficient of variation of systolic blood pressure across visits from 12 weeks poststroke or TIA onward. BPV was significantly higher in patients with a history of stroke or TIA than those without. BPV was a predictor of recurrent stroke in the pooled analysis. In the ASCOT study, 252 patients (12.3%) had a recurrent stroke among 2046 with a history of stroke. Incidence of recurrent stroke was significantly higher in the highest BPV quartile (17.8%) compared with the lowest quartile (10.5%); by treatment arm, this reached significance for the amlodipine‐arm only (high‐BPV: 18.7% versus low‐BPV: 12.9%; P=0.029). Of the 2173 patients from the ALLHAT with a history of stroke or TIA, patients with the highest quartile of BPV had a higher incidence of recurrent stroke (9.6%) compared with the lowest quartile BPV (5.5%); by treatment arm, this reached significance for the chlorthalidone‐arm only (high‐BPV: 12.1% versus low‐BPV: 5.4%; P=0.007). Conclusions Visit‐to‐visit BPV is a predictor of recurrent stroke in patients with a history of stroke or TIA on antihypertensive treatment. Considering BPV following a stroke may be important to reduce the risk for a recurrent stroke.

Background and Purpose The location of cerebral microbleeds (CMBs) may differ according to ischemic stroke subtype, and the underlying pathomechanism may differ by their location. Here, we investigated the characteristics of CMBs according to various ischemic stroke subtypes to verify this issue. Methods Patients with acute ischemic stroke were consecutively included. The presence of CMBs was determined by gradient echo image sequence. The distribution of CMBs was classified as deep, lobar, or diffuse (both deep and lobar). The prevalence, risk factors, and distribution of CMBs were compared among patients with different stroke subtypes. Factors associated with the distribution of CMBs were investigated. Results Among the 1033 patients included in this study, ischemic stroke subtypes were classified as large artery atherosclerosis (LAA; n=432), small vessel occlusion (SVO; n=304), and cardioembolism (CE; n=297). The prevalence of CMBs was highest in patients with SVO (40.5%), followed by CE (33.0%) and LAA (24.8%; P

Background and Purpose The primary mechanism underlying paramedian pontine infarction (PPI) is atheroma obliterating the perforators. Here, we encountered a patient with PPI in the post-stenotic area of basilar artery (BA) without a plaque, shown by high-resolution magnetic resonance imaging (HR-MRI). We performed an experiment using a 3D-printed BA model and a particle image velocimetry (PIV) to explore the hemodynamic property of the post-stenotic area and the mechanism of PPI. Methods 3D-model of a BA stenosis was reconstructed with silicone compound using a 3D-printer based on the source image of HR-MRI. Working fluid seeded with fluorescence particles was used and the velocity of those particles was measured horizontally and vertically. Furthermore, microtubules were inserted into the posterior aspect of the model to measure the flow rates of perforators (pre-and post-stenotic areas). The flow rates were compared between the microtubules. Results A recirculating flow was observed from the post-stenotic area in both directions forming a spiral shape. The velocity of the flow in these regions of recirculation was about one-tenth that of the flow in other regions. The location of recirculating flow well corresponded with the area with low-signal intensity at the time-of-flight magnetic resonance angiography and the location of PPI. Finally, the flow rate through the microtubule inserted into the post-stenotic area was significantly decreased comparing to others (P

Background: Some patients with acute stroke symptoms do not show hyperintensities on diffusion-weighted image (DWI). A few case reports have indicated that acutely developed cerebral microbleeds (CMBs) might cause focal symptoms. This study sought to investigate the incidence and characteristics of symptomatic CMBs in the patients with acute stroke symptoms but without DWI ischemic lesions.Methods: We enrolled the patients with acute stroke symptoms who underwent magnetic resonance imaging including DWI and gradient echo (GRE) sequences within 7 days after symptom onset, at our prospective stroke registry. We then identified patients without DWI-positive ischemic lesions but with CMBs in the relevant brain regions.Results: Between January 2005 and February 2012, we identified 235 DWI-negative transient ischemic attack (n = 221) and stroke (n = 14) patients from 2129 consecutive patients at our registry. In total, 16 patients had CMBs corresponding to the focal symptoms. Among these 16 patients, 12 patients showed a hyperintense rim on DWI around a microbleed suspected to be related to focal symptoms; of the 12 patients, 7 experienced stroke symptoms for more than 24 h. However, the symptoms in the remaining patients (5 patients with the hyperintense rim and 4 patients without the hyperintense rim) improved within 24 h.Conclusion: Symptomatic microbleeds are infrequent but not rare in the patients with acute stroke symptoms. Perihematomal edema around an acute CMB can cause a hyperintense rim on DWI. Our results suggest that a combination of DWI and GRE imaging can help diagnose acute symptomatic CMBs.

PurposeThe hyperintense acute reperfusion marker (HARM) is a delayed enhancement of the subarachnoid or subpial space observed on post-contrast fluid-attenuated inversion recovery (FLAIR) images and is associated with permeability changes to the blood–brain barrier in acute stroke. We investigated the relationship between HARM and stroke etiology based on the Trial of ORG 10172 in Acute Stroke Treatment (TOAST) classification. In addition, we evaluated the relationship between HARM and stroke locations with respect to vascular territories and anatomic compartments.Materials and methodsWe recruited 264 consecutive patients (109 women; mean age 68.63 years) who were diagnosed with acute ischemic stroke and underwent brain magnetic resonance imaging (MRI) including post-contrast FLAIR and DWI within 7 days of symptom onset from May 2015 to March 2016 for this retrospective study. Post-contrast FLAIR images were obtained 5 min after gadolinium administration. The mean time interval between the onset of stroke symptoms and MRI acquisition in total included patients was 18 h and 7 min (median 12 h and 57 min, range 2–127 h). We analyzed the overall incidence and distribution patterns of HARM in acute ischemic stroke cases and compared the relative incidence and distribution patterns of HARM between the subgroups of stroke etiology based on conventional TOAST classification. We obtained odds ratio (OR) of HARM in different stroke locations based on vascular territories and anatomical compartments. This study was approved by our institutional review board.ResultsAmong the 264 patients, 67 (25.38%) patients were HARM positive and 197 (74.62%) patients were HARM negative. There was significant difference in HARM incidence among the stroke subgroups (p

Although intravenous administration of tissue plasminogen activator is the only proven treatment after acute ischemic stroke, there is always a concern of hemorrhagic risk after thrombolysis. Therefore, selection of patients with potential benefits in overcoming potential harms of thrombolysis is of great importance. Despite the practical issues in using magnetic resonance imaging (MRI) for acute stroke treatment, multimodal MRI can provide useful information for accurate diagnosis of stroke, evaluation of the risks and benefits of thrombolysis, and prediction of outcomes. For example, the high sensitivity and specificity of diffusion-weighted image (DWI) can help distinguish acute ischemic stroke from stroke-mimics. Additionally, the lesion mismatch between perfusion-weighted image (PWI) and DWI is thought to represent potential salvageable tissue by reperfusion therapy. However, the optimal threshold to discriminate between benign oligemic areas and the penumbra is still debatable. Signal changes of fluid-attenuated inversion recovery image within DWI lesions may be a surrogate marker for ischemic lesion age and might indicate risks of hemorrhage after thrombolysis. Clot sign on gradient echo image may reflect the nature of clot, and their location, length and morphology may provide predictive information on recanalization by reperfusion therapy. However, previous clinical trials which solely or mainly relied on perfusion-diffusion mismatch for patient selection, failed to show benefits of MRI-based thrombolysis. Therefore, understanding the clinical implication of various useful MRI findings and comprehensively incorporating those variables into therapeutic decision-making may be a more reasonable approach for expanding the indication of acute stroke thrombolysis.

PurposeSmoking is a well known risk factor for stroke. The cerebral arteries may be uniquely susceptible to the atherosclerotic effects of smoking, such that it has a different risk profile for stroke compared with other atherosclerosis risk factors. It remains uncertain whether smoking is associated specifically with intracranial (IC) or extracranial (EC) atherosclerotic cerebrovascular disease. The aim of this study design will be to evaluate the association between smoking and severe IC stenosis, adjusting for other atherosclerosis risk factors, particularly age distribution.Study designThis is a retrospective cohort study design. Participants are patients (n=1714) with severe atherosclerotic stenosis undergoing cerebral catheter angiography because of stroke or transient ischaemic attack. All atherosclerotic steno-occlusive lesions are described in terms of location (anterior versus posterior circulation, IC versus EC, or intradural versus extradural). The atherosclerotic or stroke risk factors for analysis include age, gender, smoking history, number of lesions (single versus multiple), cardiac disease, diabetes mellitus, hypertension, family history, dyslipidemia, history of previous stroke, alcohol intake, metabolic syndrome and body mass index. Statistical analysis includes univariate analysis followed by multivariate logistic regression. The relationship between IC atherosclerotic stenosis and smoking will be assessed. Differences in risk factor distribution is analysed according to age at intervals of 10 years. Significant risk factors associated with IC atherosclerotic stenosis will also be assessed by multivariate logistic regression analysis.SummaryThis is an analytical study design that intends to measure the association between IC or EC atherosclerotic stenosis and smoking and other risk factors. We anticipate that it will have the power to detect any relationship between smoking and IC atherosclerotic lesions especially in younger patients.