Impact of Cerebral Microbleeds in Stroke Patients with Atrial Fibrillation.

OBJECTIVES: Cerebral microbleeds are associated with the risks of ischemic stroke and intracranial hemorrhage, causing clinical dilemmas for antithrombotic treatment decisions. We aimed to evaluate the risks of intracranial hemorrhage and ischemic stroke associated with microbleeds in patients with atrial fibrillation treated with vitamin K antagonists, direct oral anticoagulants, antiplatelets, and combination therapy (i.e. concurrent oral anticoagulant and antiplatelet). METHODS: We included patients with documented atrial fibrillation from the pooled individual patient data analysis by the Microbleeds International Collaborative Network. Risks of subsequent intracranial hemorrhage and ischemic stroke were compared between patients with and without microbleeds, stratified by antithrombotic use. RESULTS: A total of 7,839 patients were included. The presence of microbleeds was associated with an increased relative risk of intracranial hemorrhage (adjusted hazard ratio [aHR] = 2.74, 95% confidence interval = 1.76-4.26) and ischemic stroke (aHR = 1.29, 95% confidence interval = 1.04-1.59). For the entire cohort, the absolute incidence of ischemic stroke was higher than intracranial hemorrhage regardless of microbleed burden. However, for the subgroup of patients taking combination of anticoagulant and antiplatelet therapy, the absolute risk of intracranial hemorrhage exceeded that of ischemic stroke in those with 2 to 4 microbleeds (25 vs 12 per 1,000 patient-years) and ≥ 11 microbleeds (94 vs 48 per 1,000 patient-years). INTERPRETATION: Patients with atrial fibrillation and high burden of microbleeds receiving combination therapy have a tendency of higher rate of intracranial hemorrhage than ischemic stroke, with potential for net harm. Further studies are needed to help optimize stroke preventive strategies in this high-risk group. ANN NEUROL 2023;94:61-74.

Radiomics using non-contrast CT to predict hemorrhagic transformation risk in stroke patients undergoing revascularization.

OBJECTIVES: This study explores whether textural features from initial non-contrast CT scans of infarcted brain tissue are linked to hemorrhagic transformation susceptibility. MATERIALS AND METHODS: Stroke patients undergoing thrombolysis or thrombectomy from Jan 2012 to Jan 2022 were analyzed retrospectively. Hemorrhagic transformation was defined using follow-up magnetic resonance imaging. A total of 94 radiomic features were extracted from the infarcted tissue on initial NCCT scans. Patients were divided into training and test sets (7:3 ratio). Two models were developed with fivefold cross-validation: one incorporating first-order and textural radiomic features, and another using only textural radiomic features. A clinical model was also constructed using logistic regression with clinical variables, and test set validation was performed. RESULTS: Among 362 patients, 218 had hemorrhagic transformations. The LightGBM model with all radiomics features had the best performance, with an area under the receiver operating characteristic curve (AUROC) of 0.986 (95% confidence interval [CI], 0.971-1.000) on the test dataset. The ExtraTrees model performed best when textural features were employed, with an AUROC of 0.845 (95% CI, 0.774-0.916). Minimum, maximum, and ten percentile values were significant predictors of hemorrhagic transformation. The clinical model showed an AUROC of 0.544 (95% CI, 0.431-0.658). The performance of the radiomics models was significantly better than that of the clinical model on the test dataset (p < 0.001). CONCLUSIONS: The radiomics model can predict hemorrhagic transformation using NCCT in stroke patients. Low Hounsfield unit was a strong predictor of hemorrhagic transformation, while textural features alone can predict hemorrhagic transformation. CLINICAL RELEVANCE STATEMENT: Using radiomic features extracted from initial non-contrast computed tomography, early prediction of hemorrhagic transformation has the potential to improve patient care and outcomes by aiding in personalized treatment decision-making and early identification of at-risk patients. KEY POINTS: • Predicting hemorrhagic transformation following thrombolysis in stroke is challenging since multiple factors are associated. • Radiomics features of infarcted tissue on initial non-contrast CT are associated with hemorrhagic transformation. • Textural features on non-contrast CT are associated with the frailty of the infarcted tissue.

Association between substantia nigra degeneration and functional outcome in patients with basal ganglia infarction.

BACKGROUND AND PURPOSE: Cerebral infarction in the basal ganglia may cause secondary and delayed neuronal degeneration in the substantia nigra (SN). However, the clinical significance of SN degeneration remains poorly understood. METHODS: This retrospective observational study included patients with acute ischemic stroke in the basal ganglia on initial diffusion-weighted imaging who underwent follow-up diffusion-weighted imaging between 4 and 30 days after symptom onset. SN degeneration was defined as a hyperintensity lesion in the SN observed on diffusion-weighted imaging. We compared functional outcomes at 3 months between patients with and without SN degeneration. A poor outcome was defined as a score of 3-6 (functional dependence or death) on the modified Rankin Scale. RESULTS: Of 350 patients with basal ganglia infarction (median age = 74.0 years, 53.7% male), 125 (35.7%) had SN degeneration. The proportion of functional dependence or death was 79.2% (99/125 patients) in patients with SN degeneration, which was significantly higher than that in those without SN degeneration (56.4%, 127/225 patients, p < 0.001). SN degeneration was more frequent in patients with functional dependence or death (99/226 patients, 43.8%) than in those with functional independence (26/124 patients, 21.0%, p < 0.001). Multivariable logistic regression analysis showed a significant association between SN degeneration and functional dependence or death (odds ratio = 2.91, 95% confidence interval = 1.17-7.21, p = 0.021). CONCLUSIONS: The study showed that patients with degeneration of SN were associated with functional dependence or death at 3 months, suggesting that secondary degeneration is a predictor of poor stroke outcomes and a potential therapeutic target.

Coagulation Factor Expression and Composition of Arterial Thrombi in Cancer-Associated Stroke.

BACKGROUND: Cancer is associated with an increased risk of stroke. Tumor cells activate platelets, induce a coagulation cascade, and generate thrombin. The composition of thrombi may reflect the mechanism of thrombosis, aiding the determination of the treatment strategy. Here, we investigated the composition and expression of coagulation factors in the thrombi of patients with cancer-associated stroke. METHODS: Patients with stroke who underwent endovascular thrombectomy between September 2014 and June 2020 and whose cerebral thrombi were obtained were divided into those with cancer-associated stroke (cancer group) and propensity score-matched patients without cancer (control group), using 1:1 matching based on age and sex. Immunohistochemistry was performed of the thrombi, and the composition and expression of coagulation factors were compared between groups. RESULTS: Among the 320 patients who underwent endovascular thrombectomy and who had thrombi obtained, this study included 23 patients with cancer and 23 matched controls. In both groups, the median age was 65 years, and 12 patients (52.2%) were men. Platelet composition was significantly higher in the cancer group than in the control group (median [interquartile range], 51.3% [28.0%-61.4%] versus 9.5% [4.8%-14.0%]; P<0.001). Among coagulation factors, thrombin (26.2% [16.2%-52.7%] versus 4.5% [1.3%-7.2%]; P<0.001) and tissue factors (0.60% [0.34%-2.06%] versus 0.37% [0.22%-0.60%]; P=0.024) were higher and factor X was lower (1.25% [0.39%-3.60%] versus 2.33% [1.67%-4.48%]; P=0.034) in the cancer group. There was a positive correlation between thrombin and platelets in the cancer group (r=0.666; P=0.001) but not in the control group (r=-0.167; P=0.627). CONCLUSIONS: Cerebral thrombi in patients with cancer-associated stroke showed higher proportions of platelets, thrombin, and tissue factors, suggesting their key roles in arterial thrombosis in cancer and providing a therapeutic perspective for preventing stroke in patients with cancer-associated stroke.

Cancer Prediction With Machine Learning of Thrombi From Thrombectomy in Stroke: Multicenter Development and Validation.

BACKGROUND: We aimed to develop and validate machine learning models to diagnose patients with ischemic stroke with cancer through the analysis of histopathologic images of thrombi obtained during endovascular thrombectomy. METHODS: This was a retrospective study using a prospective multicenter registry which enrolled consecutive patients with acute ischemic stroke from South Korea who underwent endovascular thrombectomy. This study included patients admitted between July 1, 2017 and December 31, 2021 from 6 academic university hospitals. Whole-slide scanning was performed for immunohistochemically stained thrombi. Machine learning models were developed using transfer learning with image slices as input to classify patients into 2 groups: cancer group or other determined cause group. The models were developed and internally validated using thrombi from patients of the primary center, and external validation was conducted in 5 centers. The model was also applied to patients with hidden cancer who were diagnosed with cancer within 1 month of their index stroke. RESULTS: The study included 70 561 images from 182 patients in both internal and external datasets (119 patients in internal and 63 in external). Machine learning models were developed for each immunohistochemical staining using antibodies against platelets, fibrin, and erythrocytes. The platelet model demonstrated consistently high accuracy in classifying patients with cancer, with area under the receiver operating characteristic curve of 0.986 (95% CI, 0.983-0.989) during training, 0.954 (95% CI, 0.937-0.972) during internal validation, and 0.949 (95% CI, 0.891-1.000) during external validation. When applied to patients with occult cancer, the model accurately predicted the presence of cancer with high probabilities ranging from 88.5% to 99.2%. CONCLUSIONS: Machine learning models may be used for prediction of cancer as the underlying cause or detection of occult cancer, using platelet-stained immunohistochemical slide images of thrombi obtained during endovascular thrombectomy.

Patent Foramen Ovale and Risk of Recurrence in Stroke of Determined Etiology.

OBJECTIVE: Patent foramen ovale (PFO) is often found in stroke patients with determined etiologies. PFO may be the actual cause of stroke in some of them. We determined whether the risk of recurrent ischemic stroke differs with PFO status in stroke patients with determined etiologies. METHODS: This study included consecutive patients with stroke of determined etiology who underwent transesophageal echocardiography. We compared the rates of recurrent cerebral infarction in patients with versus without PFO, and according to PFO-Associated Stroke Causal Likelihood (PASCAL) classification. RESULTS: Of 2,314 included patients, 827 (35.7%) had PFO. During a median follow-up of 4.4 years, cerebral infarction recurred in 202 (8.7%). In multivariate modified Cox regression analyses, recurrence of infarction did not significantly differ between patients with PFO and those without PFO (hazard ratio [HR] = 0.86, 95% confidence interval [CI] = 0.64-1.17, p = 0.339). Interaction analysis showed a significant effect of PFO in patients aged <65 years (adjusted p for interaction = 0.090). PFO was independently associated with a decreased risk of recurrent infarction in patients younger than 65 years (HR = 0.41, 95% CI = 0.20-0.85, adjusted p = 0.016). Patients with probable PFO-associated stroke on the PASCAL classification had a significantly lower risk of recurrent infarction than those without PFO (HR = 0.31, 95% CI = 0.10-0.97, p = 0.044). INTERPRETATION: Considering the generally low risk of recurrence in PFO-associated stroke, PFO may be the actual cause of stroke in some patients with determined etiologies, especially younger patients or those with PFO features of probable PFO-associated stroke. ANN NEUROL 2022;92:596-606.

Prediction of cerebral hemorrhagic transformation after thrombectomy using a deep learning of dual-energy CT.

OBJECTIVES: To develop and validate a deep learning model for predicting hemorrhagic transformation after endovascular thrombectomy using dual-energy computed tomography (CT). MATERIALS AND METHODS: This was a retrospective study from a prospective registry of acute ischemic stroke. Patients admitted between May 2019 and February 2023 who underwent endovascular thrombectomy for acute anterior circulation occlusions were enrolled. Hemorrhagic transformation was defined using follow-up magnetic resonance imaging or CT. The deep learning model was developed using post-thrombectomy dual-energy CT to predict hemorrhagic transformation within 72 h. Temporal validation was performed with patients who were admitted after July 2022. The deep learning model's performance was compared with a logistic regression model developed from clinical variables using the area under the receiver operating characteristic curve (AUC). RESULTS: Total of 202 patients (mean age 71.4 years ± 14.5 [standard deviation], 92 men) were included, with 109 (54.0%) patients having hemorrhagic transformation. The deep learning model performed consistently well, showing an average AUC of 0.867 (95% confidence interval [CI], 0.815-0.902) upon five-fold cross validation and AUC of 0.911 (95% CI, 0.774-1.000) with the test dataset. The clinical variable model showed an AUC of 0.775 (95% CI, 0.709-0.842) on the training dataset (p < 0.01) and AUC of 0.634 (95% CI, 0.385-0.883) on the test dataset (p = 0.06). CONCLUSION: A deep learning model was developed and validated for prediction of hemorrhagic transformation after endovascular thrombectomy in patients with acute stroke using dual-energy computed tomography. CLINICAL RELEVANCE STATEMENT: This study demonstrates that a convolutional neural network (CNN) can be utilized on dual-energy computed tomography (DECT) for the accurate prediction of hemorrhagic transformation after thrombectomy. The CNN achieves high performance without the need for region of interest drawing. KEY POINTS: • Iodine leakage on dual-energy CT after thrombectomy may be from blood-brain barrier disruption. • A convolutional neural network on post-thrombectomy dual-energy CT enables individualized prediction of hemorrhagic transformation. • Iodine leakage is an important predictor of hemorrhagic transformation following thrombectomy for ischemic stroke.

Long Sleep Duration and Dissatisfaction with Sleep Quality Are Associated with Ischemic Stroke in Young Patients.

INTRODUCTION: Suboptimal sleep duration and poor sleep quality have been proposed to increase stroke risk. However, their significance in young ischemic stroke is unclear. We aimed to investigate the importance of sleep duration and quality on young ischemic stroke patients. METHODS: A multicenter matched case-control study was performed to evaluate under-recognized risk factors in young (<45 years) ischemic stroke patients in 8 tertiary hospitals in Korea. A total of 225 patients and 225 age- and sex-matched controls were enrolled in the same period. Detailed information about patients' demographics, socioeconomic state, and traditional and nontraditional risk factors including sleep-related factors were obtained using structured questionnaires. Risk of ischemic stroke was estimated using conditional logistic regression analysis. RESULTS: Although average sleep duration was similar in patients and controls, patients were more likely to have long (≥9 h) or extremely short (<5 h) sleep durations. In addition, the proportion of subjects with dissatisfaction with sleep quality was higher in patients than controls (66.2 vs. 49.3%, p < 0.001). In multivariable conditional logistic regression analysis, long sleep duration (OR: 11.076, 95% CI: 1.819-67.446, p = 0.009) and dissatisfaction with sleep quality (OR: 2.116, 95% CI: 1.168-3.833, p = 0.013) were independently associated with risk of ischemic stroke. CONCLUSIONS: Long sleep duration and dissatisfaction with sleep quality may be associated with increased risk of ischemic stroke in young adults. Improving sleep habit or quality could be important for reducing the risk of ischemic stroke.

NSrp70 is a lymphocyte-essential splicing factor that controls thymocyte development.

Alternative pre-mRNA splicing is a critical step to generate multiple transcripts, thereby dramatically enlarging the proteomic diversity. Thus, a common feature of most alternative splicing factor knockout models is lethality. However, little is known about lineage-specific alternative splicing regulators in a physiological setting. Here, we report that NSrp70 is selectively expressed in developing thymocytes, highest at the double-positive (DP) stage. Global splicing and transcriptional profiling revealed that NSrp70 regulates the cell cycle and survival of thymocytes by controlling the alternative processing of various RNA splicing factors, including the oncogenic splicing factor SRSF1. A conditional-knockout of Nsrp1 (NSrp70-cKO) using CD4Cre developed severe defects in T cell maturation to single-positive thymocytes, due to insufficient T cell receptor (TCR) signaling and uncontrolled cell growth and death. Mice displayed severe peripheral lymphopenia and could not optimally control tumor growth. This study establishes a model to address the function of lymphoid-lineage-specific alternative splicing factor NSrp70 in a thymic T cell developmental pathway.

Intensive vs Conventional Blood Pressure Lowering After Endovascular Thrombectomy in Acute Ischemic Stroke: The OPTIMAL-BP Randomized Clinical Trial.

Importance: Optimal blood pressure (BP) control after successful reperfusion with endovascular thrombectomy (EVT) for patients with acute ischemic stroke is unclear. Objective: To determine whether intensive BP management during the first 24 hours after successful reperfusion leads to better clinical outcomes than conventional BP management in patients who underwent EVT. Design, Setting, and Participants: Multicenter, randomized, open-label trial with a blinded end-point evaluation, conducted across 19 stroke centers in South Korea from June 2020 to November 2022 (final follow-up, March 8, 2023). It included 306 patients with large vessel occlusion acute ischemic stroke treated with EVT and with a modified Thrombolysis in Cerebral Infarction score of 2b or greater (partial or complete reperfusion). Interventions: Participants were randomly assigned to receive intensive BP management (systolic BP target <140 mm Hg; n = 155) or conventional management (systolic BP target 140-180 mm Hg; n = 150) for 24 hours after enrollment. Main Outcomes and Measures: The primary outcome was functional independence at 3 months (modified Rankin Scale score of 0-2). The primary safety outcomes were symptomatic intracerebral hemorrhage within 36 hours and death related to the index stroke within 3 months. Results: The trial was terminated early based on the recommendation of the data and safety monitoring board, which noted safety concerns. Among 306 randomized patients, 305 were confirmed eligible and 302 (99.0%) completed the trial (mean age, 73.0 years; 122 women [40.4%]). The intensive management group had a lower proportion achieving functional independence (39.4%) than the conventional management group (54.4%), with a significant risk difference (-15.1% [95% CI, -26.2% to -3.9%]) and adjusted odds ratio (0.56 [95% CI, 0.33-0.96]; P = .03). Rates of symptomatic intracerebral hemorrhage were 9.0% in the intensive group and 8.1% in the conventional group (risk difference, 1.0% [95% CI, -5.3% to 7.3%]; adjusted odds ratio, 1.10 [95% CI, 0.48-2.53]; P = .82). Death related to the index stroke within 3 months occurred in 7.7% of the intensive group and 5.4% of the conventional group (risk difference, 2.3% [95% CI, -3.3% to 7.9%]; adjusted odds ratio, 1.73 [95% CI, 0.61-4.92]; P = .31). Conclusions and Relevance: Among patients who achieved successful reperfusion with EVT for acute ischemic stroke with large vessel occlusion, intensive BP management for 24 hours led to a lower likelihood of functional independence at 3 months compared with conventional BP management. These results suggest that intensive BP management should be avoided after successful EVT in acute ischemic stroke. Trial Registration: ClinicalTrials.gov Identifier: NCT04205305.

Impact of Renal Function on Short-Term Outcome After Reperfusion Therapy in Patients With Ischemic Stroke.

BACKGROUND: A high and low estimated glomerular filtration rate (eGFR) could affect outcomes after reperfusion therapy for ischemic stroke. This study aimed to determine whether renal function based on eGFR affects mortality risk in patients with ischemic stroke within 6 months following reperfusion therapy. METHODS: This prospective registry-based cohort study included 2266 patients who received reperfusion therapy between January 2000 and September 2019 and were registered in the SECRET (Selection Criteria in Endovascular Thrombectomy and Thrombolytic Therapy) study or the Yonsei Stroke Cohort. A high and low eGFR were based on the Chronic Kidney Disease Epidemiology Collaboration equation and defined, respectively, as the 5th and 95th percentiles of age- and sex-specific eGFR. Occurrence of death within 6 months was compared among the groups according to their eGFR such as low, normal, or high eGFR. RESULTS: Of the 2266 patients, 2051 (90.5%) had a normal eGFR, 110 (4.9%) a low eGFR, and 105 (4.6%) a high eGFR. Patients with high eGFR were younger or less likely to have hypertension, diabetes, or atrial fibrillation than the other groups. Active cancer was more prevalent in the high-eGFR group. During the 6-month follow-up, there were 24 deaths (22.9%) in the high-eGFR group, 37 (33.6%) in the low-eGFR group, and 237 (11.6%) in the normal-eGFR group. After adjusting for variables with P<0.10 in the univariable analysis, 6-month mortality was independently associated with high eGFR (hazard ratio, 2.22 [95% CI, 1.36-3.62]; P=0.001) and low eGFR (HR, 2.29 [95% CI, 1.41-3.72]; P=0.001). These associations persisted regardless of treatment modality or various baseline characteristics. CONCLUSIONS: High eGFR as well as low eGFR were independently associated with 6-month mortality after reperfusion therapy. Kidney function could be considered a prognostic factor in patients with ischemic stroke after reperfusion therapy.

Short-Term Cessation of Dabigatran Causes a Paradoxical Prothrombotic State.

OBJECTIVE: It is unclear if stopping treatment with dabigatran, a new oral anticoagulant (NOAC), induces a paradoxical rebound prothrombotic state. We investigated if short-term (1-3 days) dabigatran cessation is associated with a higher thrombus volume than expected from a simple reversal of the anticoagulant effect. METHODS: Ten-week-old C57Bl/6 mice (n = 338) received one of the following oral treatments: phosphate-buffered saline (PBS), dabigatran for 7 days with or without 1 to 4 day cessation, and aspirin in either a single dose or daily for 7 days. Some of the animals that ceased dabigatran for 1 to 3 days received single-dose aspirin. Thereafter, we induced FeCl3 -mediated carotid thrombosis in 130 mice, after which we performed micro computed tomography thrombus imaging. The other 208 mice underwent coagulation assays or platelet function tests. As an explorative pilot study, we reviewed the medical records of 18 consecutive patients with NOAC cessation-related cerebral infarction in a large acute stroke cohort. RESULTS: We observed a ~ 40% higher volume of carotid thrombus after dabigatran cessation at 1 to 3 days than after vehicle treatment and showed that this effect could be prevented by single-dose aspirin pretreatment. Dabigatran cessation unduly increased platelet aggregability for 2 days after drug cessation, an effect mediated through thrombin or arachidonic acid, which effect was significantly attenuated by single-dose aspirin pretreatment. In patients, short-term (≤ 3 days) cessation of NOAC therapy, compared with longer-term (≥ 5 days) cessation, tended to be associated with relatively high stroke severity. INTERPRETATION: We provide the first preclinical evidence that a rebound prothrombotic state follows short-term cessation of dabigatran therapy. ANN NEUROL 2021;89:444-458.

Immediate and Long-Term Outcomes of Reperfusion Therapy in Patients With Cancer.

Background and Purpose: Patients with acute stroke are often accompanied by comorbidities, such as active cancer. However, adequate treatment guidelines are not available for these patients. The purpose of this study was to evaluate the association between cancer and the outcomes of reperfusion therapy in patients with stroke. Methods: We compared treatment outcomes in patients who underwent reperfusion therapy, using a nationwide reperfusion therapy registry. We divided the patients into 3 groups according to cancer activity: active cancer, nonactive cancer, and without a history of cancer. We investigated reperfusion processes, 24-hour neurological improvement, adverse events, 3-month functional outcome, and 6-month survival and related factors after reperfusion therapy. Results: Among 1338 patients who underwent reperfusion therapy, 62 patients (4.6%) had active cancer, 78 patients (5.8%) had nonactive cancer, and 1198 patients (89.5%) had no history of cancer. Of the enrolled patients, 969 patients received intravenous thrombolysis and 685 patients underwent endovascular treatment (316 patients received combined therapy). Patients with active cancer had more comorbidities and experienced more severe strokes; however, they showed similar 24-hour neurological improvement and adverse events, including cerebral hemorrhage, compared with the other groups. Although the functional outcome at 3 months was poorer than the other groups, 36.4% of patients with active cancer showed functional independence. Additionally, 52.9% of the patients with determined stroke etiology showed functional independence despite active cancer. During the 6-month follow-up, 46.6% of patients with active cancer died, and active cancer was independently associated with poor survival (hazard ratio, 3.973 [95% CI, 2.528­6.245]). Conclusions: In patients with active cancer, reperfusion therapy showed similar adverse events and short-term outcomes to that of other groups. While long-term prognosis was worse in the active cancer group than the nonactive cancer groups, not negligible number of patients had good functional outcomes, especially those with determined stroke mechanisms.

The role of cardiac CT throughout the full cardiac cycle in diagnosing patent foramen ovale in patients with acute stroke.

OBJECTIVES: We explored the hypothesis that the diagnostic performance of cardiac computed tomography (CT) throughout the full cardiac cycle would be superior to single-phase CT and comparable to transesophageal echocardiography (TEE) in diagnosing patent foramen ovale (PFO). METHODS AND RESULTS: From May 2011 to April 2015, 978 patients with stroke were diagnosed with PFO by TEE. In patients with stroke, cardiac CT was performed if the patients had more than two cardiovascular risk factors. We prospectively enrolled 70 patients with an indication for cardiac CT. Cardiac CT images were reconstructed at 10% increments of the R-R interval. The sensitivity of cardiac CT throughout the full cardiac cycle in diagnosing PFO was compared to that for TEE and single-phase cardiac CT. To evaluate the specificity of cardiac CT, we analyzed patients without PFO confirmed by TEE who underwent cardiac CT within 1 month of pre-cardiac surgery. Sixty-six patients with cardiac CT and TEE were included in the final analysis. Throughout the full cardiac cycle, cardiac CT had a sensitivity of 89.4% and a specificity of 92.3% in diagnosing PFO, compared to TEE as a reference. PFO was primarily detected in the 60% and 70% intervals in 10-phase reconstructed images. The sensitivity of PFO diagnosis with cardiac CT was 81.8% when analyzing both the 60% and 70% intervals instead of the full cardiac cycle. CONCLUSION: Cardiac CT throughout the full cardiac cycle outperforms single-phase cardiac CT in detecting PFO. Cardiac CT can be used as an alternative method to TEE for detecting PFO in stroke patients. KEY POINTS: • Throughout the full cardiac cycle, cardiac computed tomography (CT) had a sensitivity of 89.4% and a specificity of 92.3% in diagnosing patent foramen ovale (PFO), compared to transesophageal echocardiography. • The sensitivity of diagnosing patent foramen ovale with cardiac CT was 81.8% when analyzing 60% and 70% R-R intervals instead of the full cardiac cycle. • Cardiac CT with retrospective electrocardiographic gating throughout the full cardiac cycle can increase the detectability of PFO, compared to single-phase cardiac CT.

Association between the severity of liver fibrosis and cardiovascular outcomes in patients with type 2 diabetes.

BACKGROUND AND AIM: Cardiovascular disease (CVD) is the principal cause of death in patients with type 2 diabetes (T2D). In this study, we assessed whether liver fibrosis predicted the risk of CVD in patients with T2D. METHODS: A total of 1481 patients who had commenced oral antidiabetic drugs to treat newly diagnosed T2D between 2006 and 2010 were recruited. The fibrosis-4 index (FIB-4), non-alcoholic fatty liver disease fibrosis score (NFS), and BARD score were used to assess fibrotic burden at the time of T2D diagnosis. RESULTS: During the follow-up period (median 88.1 [interquartile range 36.6-113.6] months), 242 (16.3%) patients developed CVD. CVD occurred frequently in older patients and was associated with hypertension; metabolic syndrome; obesity; smoking; administration of statin, which is an antihyperlipidemic drug; lower platelet counts; lower alanine aminotransferase, total cholesterol, and HbA1c levels; higher C-peptide and homeostatic model assessment of insulin resistance levels; and higher FIB-4, NFS, and BARD score (all P < 0.05). FIB-4 (hazard ratio [HR] = 1.163), NFS (HR = 1.322), BARD score (HR = 1.564), metabolic syndrome (HR = 1.556), smoking (HR = 2.829), and statin use (HR = 0.603) independently predicted the risk of CVD (all P < 0.05). The cumulative incidence of CVD was significantly different among groups stratified by liver fibrotic burden (all P < 0.05, log-rank test). Competing risk analysis showed a significant association between the severity of liver fibrosis and CVD development (all P < 0.001, Gray's test). CONCLUSIONS: The severity of liver fibrosis independently predicted CVD in patients with T2D. Thus, assessment of liver fibrosis might allow physicians to optimize the timing of appropriate cardiovascular interventions in such patients.

Prognostic effect of increased left ventricular wall thickness in severe aortic stenosis.

BACKGROUND: It is unclear whether increased left ventricular (LV) thickness is associated with worse clinical outcomes in severe aortic stenosis (AS). The aim of this study was to determine the effect of increased LV wall thickness (LVWT) on major clinical outcomes in patients with severe AS. METHODS AND RESULTS: This study included 290 severe AS patients (mean age 69.4 ± 11.0 years; 136 females) between January 2008 and December 2018. For outcome assessment, the endpoint was defined as death from all causes, cardiovascular death, and the aortic valve replacement (AVR) surgery rate. During follow-up (48.7 ± 39.0 months), 157 patients had AVR, 43 patients died, and 28 patients died from cardiovascular causes. Patients with increased LVWT underwent AVR surgery much more than those without LVWT (60.0% vs. 39.0%, p < 0.001). Furthermore, in patients with increased LVWT, the all-cause and cardiovascular death rates were significantly lower in the AVR group than in the non-AVR group (8.8% vs. 27.3%, p < 0.001, 4.8%, vs. 21.0%, p < 0.001). Multivariate analysis revealed that increased LVWT, age, dyspnea, and AVR surgery were significantly correlated with cardiovascular death. CONCLUSIONS: In patients with severe AS, increased LVWT was associated with a higher AVR surgery rate and an increased rate of cardiovascular death independent of other well-known prognostic variates. Thus, these findings suggest that increased LVWT might be used as a potential prognostic factor in severe AS patients.

Virtual reality-based neurological examination teaching tool(VRNET) versus standardized patient in teaching neurological examinations for the medical students: a randomized, single-blind study.

BACKGROUND: The conventional methods for teaching neurological examination with real patients to medical students have some limitations if the patient with the symptom or disease is not available. Therefore, we developed a Virtual Reality-based Neurological Examination Teaching Tool (VRNET) and evaluated its usefulness in in teaching neurological examinations for the medical students. METHODS: In this prospective, randomized, single-blind study, we recruited 98 medical students and divided them into two groups: 1) A standardized patient(SP) group that received the clinical performance examination utilizing standard patients complaining of dizziness was provided neurological findings using conventional method such as verbal description, photographs, and video clips; 2) A SP with VRNET group that was provided the neurological findings using the newly developed tool. Among the 98 students, 3 did not agree to participate, and 95 were enrolled in this study. The SP group comprised 39 students and the SP with VRNET group had 56 students. RESULTS: There were no statistical differences in VRNET's realness and student satisfaction between the SP and SP with VRNET groups. However, a statistically significant difference was found in the Neurologic Physical Exam (NPE) score (p = 0.043); the SP with VRNET group had higher NPE scores (3.81 ± 0.92) than the SP group (3.40 ± 1.01). CONCLUSIONS: VRNET is useful in teaching senior (graduating) medical students with SP with a neurologic problem.

Modeling Sialidosis with Neural Precursor Cells Derived from Patient-Derived Induced Pluripotent Stem Cells.

Sialidosis, caused by a genetic deficiency of the lysosomal sialidase gene (NEU1), is a systemic disease involving various tissues and organs, including the nervous system. Understanding the neurological dysfunction and pathology associated with sialidosis remains a challenge, partially due to the lack of a human model system. In this study, we have generated two types of induced pluripotent stem cells (iPSCs) with sialidosis-specific NEU1G227R and NEU1V275A/R347Q mutations (sialidosis-iPSCs), and further differentiated them into neural precursor cells (iNPCs). Characterization of NEU1G227R- and NEU1V275A/R347Q- mutated iNPCs derived from sialidosis-iPSCs (sialidosis-iNPCs) validated that sialidosis-iNPCs faithfully recapitulate key disease-specific phenotypes, including reduced NEU1 activity and impaired lysosomal and autophagic function. In particular, these cells showed defective differentiation into oligodendrocytes and astrocytes, while their neuronal differentiation was not notably affected. Importantly, we found that the phenotypic defects of sialidosis-iNPCs, such as impaired differentiation capacity, could be effectively rescued by the induction of autophagy with rapamycin. Our results demonstrate the first use of a sialidosis-iNPC model with NEU1G227R- and NEU1V275A/R347Q- mutation(s) to study the neurological defects of sialidosis, particularly those related to a defective autophagy-lysosome pathway, and may help accelerate the development of new drugs and therapeutics to combat sialidosis and other LSDs.

Initial Stroke Severity in Patients With Atrial Fibrillation According to Antithrombotic Therapy Before Ischemic Stroke.

BACKGROUND AND PURPOSE: Atrial fibrillation (AF) is the leading cause of ischemic stroke. Preventive antithrombotic use, especially for anticoagulation, reduces the incidence of ischemic stroke in patients with AF. Using data from the nationwide multicenter stroke registry, we investigated the trends of preceding antithrombotic medication use in patients with acute ischemic stroke (AIS) with AF and its association with initial stroke severity and in-hospital outcomes. METHODS: This study included 6786 patients with AIS with known AF before stroke admission across 39 hospitals between June 2008 and December 2018. We collected the data on antithrombotic medication use (no antithrombotic/antiplatelet/anticoagulant) preceding AIS. Initial stroke severity was measured using the National Institutes of Health Stroke Scale, and in-hospital outcome was determined by modified Rankin Scale score at discharge. RESULTS: During the study period, anticoagulant use continued to increase. However, nearly one-third of patients with AIS with known AF did not receive antithrombotics before stroke. Initial National Institutes of Health Stroke Scale scores varied according to preceding antithrombotic therapy (P<0.001). It was higher in patients who did not receive antithrombotics than in those who received antiplatelets or anticoagulants (median National Institutes of Health Stroke Scale score: 8 versus 7 and 8 versus 6, respectively). Favorable outcome at discharge (modified Rankin Scale score, 0-2) was more prevalent in patients who received antiplatelets or anticoagulants (P<0.001). Use of antiplatelets (odds ratio, 1.23 [95% CI, 1.09-1.38]) and anticoagulants (odds ratio, 1.31 [95% CI, 1.15-1.50]) was associated with a mild initial neurological deficit (National Institutes of Health Stroke Scale score ≤5) in patients with AIS with AF. CONCLUSIONS: Throughout the study period, the proportion of patients taking anticoagulants increased among patients with AIS with known AF. However, a large portion of AF patients still did not receive antithrombotics before AIS. Furthermore, prehospitalization use of anticoagulants was associated with a significantly higher likelihood of a mild initial neurological deficit and favorable outcome at discharge.

Nonalcoholic Fatty Liver Disease and Sarcopenia Are Independently Associated With Cardiovascular Risk.

OBJECTIVES: Nonalcoholic fatty liver disease (NAFLD) and sarcopenia have a close association with an increased risk of atherosclerotic cardiovascular disease (ASCVD). This study investigated the influence of NAFLD and sarcopenia on ASCVD risk. METHODS: Data from the 2008-2011 Korean National Health and Nutrition Examination Surveys database were analyzed (n = 7,191). The sarcopenia index was calculated using dual-energy x-ray absorptiometry. Sarcopenia was defined as the lowest quintile sarcopenia index value (cutoffs = 0.882 for men and 0.582 for women). NAFLD was defined as a comprehensive NAFLD score ≥40. Liver fibrosis was assessed using the fibrosis-4 (FIB-4) index. ASCVD risk was evaluated using American College of Cardiology/American Heart Association guidelines. High probability of ASCVD was defined as ASCVD risk >10%. RESULTS: The prevalence rates of NAFLD and sarcopenia were 31.2% (n = 2,241) and 19.5% (n = 1,400), respectively. The quartile-stratified ASCVD risk scores were positively associated with NAFLD and sarcopenia (all P for trend < 0.001). Subjects with both NAFLD and sarcopenia had a higher risk for high probability of ASCVD (odds ratio = 1.83, P = 0.014) compared with controls without NAFLD and sarcopenia. Among subjects with NAFLD, FIB-4-defined significant liver fibrosis and sarcopenia additively raised the risk for high probability of ASCVD (odds ratio = 3.56, P < 0.001) compared with controls without FIB-4-defined significant liver fibrosis or sarcopenia. DISCUSSION: NAFLD and sarcopenia were significantly associated with an increased risk of ASCVD in the general population. In addition, NAFLD with significant liver fibrosis and sarcopenia were significantly associated with an increased risk of ASCVD in subjects with NAFLD.