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1.
Journal of Stroke ; : 300-311, 2024.
مقالة ي الانجليزية | WPRIM | ID: wpr-1044094

الملخص

Background@#and Purpose Accurate classification of ischemic stroke subtype is important for effective secondary prevention of stroke. We used diffusion-weighted image (DWI) and atrial fibrillation (AF) data to train a deep learning algorithm to classify stroke subtype. @*Methods@#Model development was done in 2,988 patients with ischemic stroke from three centers by using U-net for infarct segmentation and EfficientNetV2 for subtype classification. Experienced neurologists (n=5) determined subtypes for external test datasets, while establishing a consensus for clinical trial datasets. Automatically segmented infarcts were fed into the model (DWI-only algorithm). Subsequently, another model was trained, with AF included as a categorical variable (DWI+AF algorithm). These models were tested: (1) internally against the opinion of the labeling experts, (2) against fresh external DWI data, and (3) against clinical trial dataset. @*Results@#In the training-and-validation datasets, the mean (±standard deviation) age was 68.0±12.5 (61.1% male). In internal testing, compared with the experts, the DWI-only and the DWI+AF algorithms respectively achieved moderate (65.3%) and near-strong (79.1%) agreement. In external testing, both algorithms again showed good agreements (59.3%–60.7% and 73.7%–74.0%, respectively). In the clinical trial dataset, compared with the expert consensus, percentage agreements and Cohen’s kappa were respectively 58.1% and 0.34 for the DWI-only vs. 72.9% and 0.57 for the DWI+AF algorithms. The corresponding values between experts were comparable (76.0% and 0.61) to the DWI+AF algorithm. @*Conclusion@#Our model trained on a large dataset of DWI (both with or without AF information) was able to classify ischemic stroke subtypes comparable to a consensus of stroke experts.

2.
Journal of Stroke ; : 252-259, 2024.
مقالة ي الانجليزية | WPRIM | ID: wpr-1044098

الملخص

Background@#and Purpose Infarct volume and other imaging markers are increasingly used as surrogate measures for clinical outcome in acute ischemic stroke research, but how improvements in these imaging surrogates translate into better clinical outcomes is currently unclear. We investigated how changes in infarct volume at 24 hours alter the probability of achieving good clinical outcome (modified Rankin Scale [mRS] 0–2). @*Methods@#Data are from endovascular thrombectomy patients from the randomized controlled ESCAPE-NA1 (Efficacy and Safety of Nerinetide for the Treatment of Acute Ischaemic Stroke) trial. Infarct volume at 24 hours was manually segmented on non-contrast computed tomography or diffusion-weighted magnetic resonance imaging. Probabilities of achieving good outcome based on infarct volume were obtained from a multivariable logistic regression model. The probability of good outcome was plotted against infarct volume using linear spline regression. @*Results@#A total of 1,099 patients were included in the analysis (median final infarct volume 24.9 mL [interquartile range: 6.6–92.2]). The relationship between total infarct volume and good outcome probability was nearly linear for infarct volumes between 0 mL and 250 mL. In this range, a 10% increase in the probability of achieving mRS 0–2 required a decrease in infarct volume of approximately 34.0 mL (95% confidence interval: -32.5 to -35.6). At infarct volumes above 250 mL, the probability of achieving mRS 0–2 probability was near zero. The relationships of tissue-specific infarct volumes and parenchymal hemorrhage volume generally showed similar patterns, although variability was high. @*Conclusion@#There seems to be a near-linear association between total infarct volume and probability of achieving good outcome for infarcts up to 250 mL, whereas patients with infarct volumes greater than 250 mL are highly unlikely to have a favorable outcome.

3.
مقالة ي الانجليزية | WPRIM | ID: wpr-1000865

الملخص

Background@#and Purpose The congestive heart failure, hypertension, age, diabetes, previous stroke/transient ischemic attack (CHA2DS2-VASc) and hypertension, abnormal renal/liver function, stroke, bleeding history or predisposition, labile international normalized ratio, elderly, drugs/alcohol (HAS-BLED) scores have been validated in estimating the risks of ischemic stroke and major bleeding, respectively, in patients with atrial fibrillation (AF). This study investigated stroke-specific predictors of major bleeding in patients with stroke and AF who were taking oral anticoagulants (OACs). @*Methods@#Subjects were selected from patients enrolled in the Korean ATrial fibrillaTion EvaluatioN regisTry in Ischemic strOke patieNts (K-ATTENTION) nationwide multicenter registry between 2013 and 2015. Patients were excluded if they were not taking OACs, had no brain imaging data, or had intracranial bleeding directly related to the index stroke. Major bleeding was defined according to International Society of Thrombosis and Haemostasis criteria. Cox regression analyses were performed to assess the associations between clinical variables and major bleeding and Kaplan-Meier estimates were performed to analyze event-free survival. @*Results@#Of a total of 3,213 patients, 1,414 subjects (mean age of 72.6 years, 52.5% males) were enrolled in this study. Major bleeding was reported in 34 patients during the median follow-up period of 1.73 years. Multivariable analysis demonstrated that initial National Institutes of Health Stroke Scale scores (hazard ratio [HR] 1.07, p=0.006), hypertension (HR 3.18, p=0.030), persistent AF type (HR 2.51, p=0.016), and initial hemoglobin level (HR 0.74, p=0.001) were independently associated with major bleeding risk. Except for hypertension, these associations remained significant after adjusting for the HAS-BLED score. Intracranial atherosclerosis presented a trend of association without statistical significance (HR 2.21, p=0.050). @*Conclusions@#This study found that major bleeding risk was independently associated with stroke-specific factors in anticoagulated patients with stroke and AF. This has the clinical implication that baseline characteristics of patients with stroke and AF should be considered in secondary prevention, which would bring the net clinical benefit of balancing recurrent stroke prevention with minimal bleeding complications.

4.
Journal of Stroke ; : 251-265, 2023.
مقالة ي الانجليزية | WPRIM | ID: wpr-1001578

الملخص

Background@#and Purpose This study aimed to evaluate whether extracellular-vesicle-incorporated microRNAs (miRNAs) are potential biomarkers for cancer-related stroke. @*Methods@#This cohort study compared patients with active cancer who had embolic stroke of unknown sources (cancer-stroke group) with patients with only cancer, patients with only stroke, and healthy individuals (control groups). The expression profiles of miRNAs encapsulated in plasma exosomes and microvesicles were evaluated using microarray and validated using quantitative real-time polymerase chain reaction. The XENO-QTM miRNA assay technology was used to determine the absolute copy numbers of individual miRNAs in an external validation cohort. @*Results@#This study recruited 220 patients, of which 45 had cancer-stroke, 76 were healthy controls, 39 were cancer controls, and 60 were stroke controls. Three miRNAs (miR-205-5p, miR-645, and miR-646) were specifically incorporated into microvesicles in patients with cancer-related stroke, cancer controls, and stroke controls. The area under the receiver operating characteristic curves of these three miRNAs were 0.7692–0.8510 for the differentiation of patients with cancer-stroke from cancer-controls and 0.8077–0.8846 for the differentiation of patients with cancer-stroke from stroke controls. The levels of several miRNAs were elevated in the plasma exosomes of patients with cancer, but were lower than those in plasma microvesicles. An in vivo study showed that systemic injection of miR-205-5p promoted the development of arterial thrombosis and elevation of D-dimer levels. @*Conclusion@#Stroke due to cancer-related coagulopathy was associated with deregulated expression of miRNAs, particularly microvesicle-incorporated miR-205-5p, miR-645, and miR-646. Further prospective studies of extracellular-vesicle-incorporated miRNAs are required to confirm the diagnostic role of miRNAs in patients with stroke and to screen the roles of miRNAs in patients with cancer.

5.
Journal of Stroke ; : 242-250, 2023.
مقالة ي الانجليزية | WPRIM | ID: wpr-1001579

الملخص

Background@#and Purpose Moderate-intensity statin plus ezetimibe versus high-intensity statin alone may provide a greater low-density lipoprotein cholesterol (LDL-C) reduction in patients with recent ischemic stroke. @*Methods@#This randomized, open-label, controlled trial assigned patients with recent ischemic stroke <90 days to rosuvastatin/ezetimibe 10/10 mg once daily (ROS10/EZT10) or to rosuvastatin 20 mg once daily (ROS20). The primary endpoint was LDL-C reduction ≥50% from baseline at 90 days. Key secondary endpoints were LDL-C <70 mg/dL and multiple lipid goal achievement, and composite of major vascular events. @*Results@#Of 584 randomized, 530 were included in the modified intention-to-treat analysis. The baseline LDL-C level was 130.2±34.7 mg/dL in the ROS10/EZT10 group and 131.0±33.9 mg/dL in the ROS20 group. The primary endpoint was achieved in 198 patients (72.5%) in the ROS10/EZT10 group and 148 (57.6%) in the ROS20 group (odds ratio [95% confidence interval], 1.944 [1.352–2.795]; P= 0.0003). LDL-C level <70 mg/dL was achieved in 80.2% and 65.4% in the ROS10/EZT10 and ROS20 groups (P=0.0001). Multiple lipid goal achievement rate was 71.1% and 53.7% in the ROS10/EZT10 and ROS20 groups (P<0.0001). Major vascular events occurred in 1 patient in the ROS10/EZT10 group and 9 in the ROS20 group (P=0.0091). The adverse event rates did not differ between the two groups. @*Conclusion@#Moderate-intensity rosuvastatin plus ezetimibe was superior to high-intensity rosuvastatin alone for intensive LDL-C reduction in patients with recent ischemic stroke. With the combination therapy, more than 70% of patients achieved LDL-C reduction ≥50% and 80% had an LDL-C <70 mg/dL at 90 days.

6.
Journal of Stroke ; : 199-213, 2023.
مقالة ي الانجليزية | WPRIM | ID: wpr-1001582

الملخص

Atrial fibrillation (AF) is a leading cause of cardioembolic stroke, which is often fatal or disabling. Prevention of stroke is crucial in AF management, and anticoagulation with non-vitamin K oral anticoagulants (NOACs) is the mainstay of AF management for stroke prevention. Because NOAC prescriptions have been surging worldwide, the development of acute ischemic stroke in patients with AF who receive NOAC treatment is an increasingly important issue in clinical practice. Moreover, these patients show a high risk of recurrence, with more than a 50% higher risk, than do patients with AF and no prior anticoagulation therapy. Careful evaluation is mandatory to determine possible causes of ischemic stroke during NOAC therapy. Differentiation of AF-unrelated stroke and demonstration of combined cardiac disease/systemic coagulopathy are important in these patients and may provide improved results in their treatment. In addition, ensuring appropriate dosing and good adherence to NOAC treatment is important. Cardioembolism, despite sufficient anticoagulation and no other causes, is the most common and challenging complication because switching to anticoagulants or adding antiplatelets to the treatment regimen does not reduce the risk of recurrent stroke, and there are no guidelines for this specific situation. This review article aimed to present the most updated data on the prevalence, causes, and secondary prevention strategies, specifically focusing on non-pharmacological approaches, together with relevant cases of AF in patients who developed ischemic stroke on NOAC therapy.

7.
مقالة ي الانجليزية | WPRIM | ID: wpr-891444

الملخص

Background@#and Purpose: Blood pressure (BP) control is strongly recommended, but BP control rate has not been well studied in patients with stroke. We evaluated the BP control rate with fimasartan-based antihypertensive therapy initiated in patients with recent cerebral ischemia. @*Methods@#This multicenter, prospective, single-arm trial involved 27 centers in South Korea. Key inclusion criteria were recent cerebral ischemia within 90 days and high BP [systolic blood pressure (SBP) >140 mm Hg or diastolic blood pressure (DBP) >90 mm Hg]. BP lowering was initiated with fimasartan. BP management during the follow-up was at the discretion of the responsible investigators. The primary endpoint was the target BP goal achievement rate (<140/90 mm Hg) at 24 weeks. Key secondary endpoints included achieved BP and BP changes at each visit, and clinical events (ClinicalTrials.gov Identifier: NCT03231293). @*Results@#Of 1,035 patients enrolled, 1,026 were included in the safety analysis, and 951 in the efficacy analysis. Their mean age was 64.1 years, 33% were female, the median time interval from onset to enrollment was 10 days, and the baseline SBP and DBP were 162.3±16.0 and 92.2±12.4 mm Hg (mean±SD). During the study period, 55.5% of patients were maintained on fimasartan monotherapy, and 44.5% received antihypertensive therapies other than fimasartan monotherapy at at least one visit. The target BP goal achievement rate at 24-week was 67.3% (48.6% at 4-week and 61.4% at 12-week). The mean BP was 139.0/81.8±18.3/11.7, 133.8/79.2±16.4/11.0, and 132.8/78.5±15.6/10.9 mm Hg at 4-, 12-, and 24-week. The treatment-emergent adverse event rate was 5.4%, including one serious adverse event. @*Conclusions@#Fimasartan-based BP lowering achieved the target BP in two-thirds of patients at 24 weeks, and was generally well tolerated.

8.
Journal of Stroke ; : 244-252, 2021.
مقالة ي الانجليزية | WPRIM | ID: wpr-892940

الملخص

Background@#and Purpose We aimed to develop a model predicting early recanalization after intravenous tissue plasminogen activator (t-PA) treatment in large-vessel occlusion. @*Methods@#Using data from two different multicenter prospective cohorts, we determined the factors associated with early recanalization immediately after t-PA in stroke patients with large-vessel occlusion, and developed and validated a prediction model for early recanalization. Clot volume was semiautomatically measured on thin-section computed tomography using software, and the degree of collaterals was determined using the Tan score. Follow-up angiographic studies were performed immediately after t-PA treatment to assess early recanalization. @*Results@#Early recanalization, assessed 61.0±44.7 minutes after t-PA bolus, was achieved in 15.5% (15/97) in the derivation cohort and in 10.5% (8/76) in the validation cohort. Clot volume (odds ratio [OR], 0.979; 95% confidence interval [CI], 0.961 to 0.997; P=0.020) and good collaterals (OR, 6.129; 95% CI, 1.592 to 23.594; P=0.008) were significant factors associated with early recanalization. The area under the curve (AUC) of the model including clot volume was 0.819 (95% CI, 0.720 to 0.917) and 0.842 (95% CI, 0.746 to 0.938) in the derivation and validation cohorts, respectively. The AUC improved when good collaterals were added (derivation cohort: AUC, 0.876; 95% CI, 0.802 to 0.950; P=0.164; validation cohort: AUC, 0.949; 95% CI, 0.886 to 1.000; P=0.036). The integrated discrimination improvement also showed significantly improved prediction (0.097; 95% CI, 0.009 to 0.185; P=0.032). @*Conclusions@#The model using clot volume and collaterals predicted early recanalization after intravenous t-PA and had a high performance. This model may aid in determining the recanalization treatment strategy in stroke patients with large-vessel occlusion.

9.
Journal of Stroke ; : 213-222, 2021.
مقالة ي الانجليزية | WPRIM | ID: wpr-892943

الملخص

Background@#and Purpose Previous studies have assessed the relationship between cerebral vessel tortuosity and intracranial aneurysm (IA) based on two-dimensional brain image analysis. We evaluated the relationship between cerebral vessel tortuosity and IA according to the hemodynamic location using three-dimensional (3D) analysis and studied the effect of tortuosity on the recurrence of treated IA. @*Methods@#We collected clinical and imaging data from patients with IA and disease-free controls. IAs were categorized into outer curvature and bifurcation types. Computerized analysis of the images provided information on the length of the arterial segment and tortuosity of the cerebral arteries in 3D space. @*Results@#Data from 95 patients with IA and 95 controls were analyzed. Regarding parent vessel tortuosity index (TI; P<0.01), average TI (P<0.01), basilar artery (BA; P=0.02), left posterior cerebral artery (P=0.03), both vertebral arteries (VAs; P<0.01), and right internal carotid artery (P<0.01), there was a significant difference only in the outer curvature type compared with the control group. The outer curvature type was analyzed, and the occurrence of an IA was associated with increased TI of the parent vessel, average, BA, right middle cerebral artery, and both VAs in the logistic regression analysis. However, in all aneurysm cases, recanalization of the treated aneurysm was inversely associated with increased TI of the parent vessels. @*Conclusions@#TIs of intracranial arteries are associated with the occurrence of IA, especially in the outer curvature type. IAs with a high TI in the parent vessel showed good outcomes with endovascular treatment.

10.
مقالة ي الانجليزية | WPRIM | ID: wpr-899148

الملخص

Background@#and Purpose: Blood pressure (BP) control is strongly recommended, but BP control rate has not been well studied in patients with stroke. We evaluated the BP control rate with fimasartan-based antihypertensive therapy initiated in patients with recent cerebral ischemia. @*Methods@#This multicenter, prospective, single-arm trial involved 27 centers in South Korea. Key inclusion criteria were recent cerebral ischemia within 90 days and high BP [systolic blood pressure (SBP) >140 mm Hg or diastolic blood pressure (DBP) >90 mm Hg]. BP lowering was initiated with fimasartan. BP management during the follow-up was at the discretion of the responsible investigators. The primary endpoint was the target BP goal achievement rate (<140/90 mm Hg) at 24 weeks. Key secondary endpoints included achieved BP and BP changes at each visit, and clinical events (ClinicalTrials.gov Identifier: NCT03231293). @*Results@#Of 1,035 patients enrolled, 1,026 were included in the safety analysis, and 951 in the efficacy analysis. Their mean age was 64.1 years, 33% were female, the median time interval from onset to enrollment was 10 days, and the baseline SBP and DBP were 162.3±16.0 and 92.2±12.4 mm Hg (mean±SD). During the study period, 55.5% of patients were maintained on fimasartan monotherapy, and 44.5% received antihypertensive therapies other than fimasartan monotherapy at at least one visit. The target BP goal achievement rate at 24-week was 67.3% (48.6% at 4-week and 61.4% at 12-week). The mean BP was 139.0/81.8±18.3/11.7, 133.8/79.2±16.4/11.0, and 132.8/78.5±15.6/10.9 mm Hg at 4-, 12-, and 24-week. The treatment-emergent adverse event rate was 5.4%, including one serious adverse event. @*Conclusions@#Fimasartan-based BP lowering achieved the target BP in two-thirds of patients at 24 weeks, and was generally well tolerated.

11.
Journal of Stroke ; : 244-252, 2021.
مقالة ي الانجليزية | WPRIM | ID: wpr-900644

الملخص

Background@#and Purpose We aimed to develop a model predicting early recanalization after intravenous tissue plasminogen activator (t-PA) treatment in large-vessel occlusion. @*Methods@#Using data from two different multicenter prospective cohorts, we determined the factors associated with early recanalization immediately after t-PA in stroke patients with large-vessel occlusion, and developed and validated a prediction model for early recanalization. Clot volume was semiautomatically measured on thin-section computed tomography using software, and the degree of collaterals was determined using the Tan score. Follow-up angiographic studies were performed immediately after t-PA treatment to assess early recanalization. @*Results@#Early recanalization, assessed 61.0±44.7 minutes after t-PA bolus, was achieved in 15.5% (15/97) in the derivation cohort and in 10.5% (8/76) in the validation cohort. Clot volume (odds ratio [OR], 0.979; 95% confidence interval [CI], 0.961 to 0.997; P=0.020) and good collaterals (OR, 6.129; 95% CI, 1.592 to 23.594; P=0.008) were significant factors associated with early recanalization. The area under the curve (AUC) of the model including clot volume was 0.819 (95% CI, 0.720 to 0.917) and 0.842 (95% CI, 0.746 to 0.938) in the derivation and validation cohorts, respectively. The AUC improved when good collaterals were added (derivation cohort: AUC, 0.876; 95% CI, 0.802 to 0.950; P=0.164; validation cohort: AUC, 0.949; 95% CI, 0.886 to 1.000; P=0.036). The integrated discrimination improvement also showed significantly improved prediction (0.097; 95% CI, 0.009 to 0.185; P=0.032). @*Conclusions@#The model using clot volume and collaterals predicted early recanalization after intravenous t-PA and had a high performance. This model may aid in determining the recanalization treatment strategy in stroke patients with large-vessel occlusion.

12.
Journal of Stroke ; : 213-222, 2021.
مقالة ي الانجليزية | WPRIM | ID: wpr-900647

الملخص

Background@#and Purpose Previous studies have assessed the relationship between cerebral vessel tortuosity and intracranial aneurysm (IA) based on two-dimensional brain image analysis. We evaluated the relationship between cerebral vessel tortuosity and IA according to the hemodynamic location using three-dimensional (3D) analysis and studied the effect of tortuosity on the recurrence of treated IA. @*Methods@#We collected clinical and imaging data from patients with IA and disease-free controls. IAs were categorized into outer curvature and bifurcation types. Computerized analysis of the images provided information on the length of the arterial segment and tortuosity of the cerebral arteries in 3D space. @*Results@#Data from 95 patients with IA and 95 controls were analyzed. Regarding parent vessel tortuosity index (TI; P<0.01), average TI (P<0.01), basilar artery (BA; P=0.02), left posterior cerebral artery (P=0.03), both vertebral arteries (VAs; P<0.01), and right internal carotid artery (P<0.01), there was a significant difference only in the outer curvature type compared with the control group. The outer curvature type was analyzed, and the occurrence of an IA was associated with increased TI of the parent vessel, average, BA, right middle cerebral artery, and both VAs in the logistic regression analysis. However, in all aneurysm cases, recanalization of the treated aneurysm was inversely associated with increased TI of the parent vessels. @*Conclusions@#TIs of intracranial arteries are associated with the occurrence of IA, especially in the outer curvature type. IAs with a high TI in the parent vessel showed good outcomes with endovascular treatment.

13.
Journal of Stroke ; : 113-123, 2021.
مقالة ي الانجليزية | WPRIM | ID: wpr-874951

الملخص

Background@#and Purpose To evaluate the outcome events and bleeding complications of the European Society of Cardiology (ESC) guideline-matched oral anticoagulant therapy for patients with acute ischemic stroke and atrial fibrillation (AF). @*Methods@#Patients with acute ischemic stroke and AF from a nationwide multicenter registry (Korean ATrial fibrillaTion EvaluatioN regisTry in Ischemic strOke patieNts [K-ATTENTION]) between January 2013 and December 2015 were included in the study. Patients were divided into the ESC guideline-matched and the non-matched groups. The primary outcome was recurrence of any stroke during the 90-day follow-up period. Secondary outcomes were major adverse cerebrovascular and cardiovascular events, ischemic stroke, intracranial hemorrhage, acute coronary syndrome, allcause mortality, and major hemorrhage. Propensity score matching and logistic regression analyses were performed to assess the effect of the treatments administered. @*Results@#Among 2,321 eligible patients, 1,126 patients were 1:1 matched to the ESC guidelinematched and the non-matched groups. As compared with the non-matched group, the ESC guideline-matched group had a lower risk of any recurrent stroke (1.4% vs. 3.4%; odds ratio [OR], 0.41; 95% confidence interval [CI], 0.18 to 0.95). The risk of recurrent ischemic stroke was lower in the ESC guideline-matched group than in the non-matched group (0.9% vs. 2.7%; OR, 0.32; 95% CI, 0.11 to 0.88). There was no significant difference in the other secondary outcomes between the two groups. @*Conclusions@#ESC guideline-matched oral anticoagulant therapy was associated with reduced risks of any stroke and ischemic stroke as compared with the non-matched therapy.

14.
Journal of Stroke ; : 1-10, 2020.
مقالة | WPRIM | ID: wpr-834647

الملخص

Systemic cancer and ischemic stroke are common conditions and two of the most frequent causes of death among the elderly. The association between cancer and stroke has been reported worldwide. Stroke causes severe disability for cancer patients, while cancer increases the risk of stroke. Moreover, cancer-related stroke is expected to increase due to advances in cancer treatment and an aging population worldwide. Because cancer and stroke share risk factors (such as smoking and obesity) and treatment of cancer can increase the risk of stroke (e.g., accelerated atherosclerosis after radiation therapy), cancer may accelerate conventional stroke mechanisms (i.e., atherosclerosis, small vessel disease, and cardiac thrombus). In addition, active cancer and chemotherapy may enhance thrombin generation causing stroke related to coagulopathy. Patients with stroke due to cancer-related coagulopathy showed the characteristics findings of etiologic work ups, D-dimer levels, and infarct patterns. In this review, we summarized the frequency of cancer-related stroke among patients with ischemic stroke, mechanisms of stroke with in cancer patients, and evaluation and treatment of cancer-related stroke. We discussed the possibility of cancer-related stroke as a stroke subtype, and presented the most recent discoveries in the pathomechanisms and treatment of stroke due to cancer-related coagulopathy.

15.
مقالة ي الانجليزية | WPRIM | ID: wpr-785398

الملخص

BACKGROUND@#Differences in the performance of suggested warfarin dosing algorithms among different ethnicities and genotypes have been reported; this necessitates the development of an algorithm with enhanced performance for specific population groups. Previous warfarin dosing algorithms underestimated warfarin doses in VKORC1 1173C carriers. We aimed to develop and validate a new warfarin dosing algorithm for Korean patients with VKORC1 1173C.@*METHODS@#A total of 109 patients carrying VKORC1 1173CT (N=105) or 1173CC (N=4) were included in this study. Multiple regression analysis was performed to deduce a new dosing algorithm. Following literature searches for genotype-guided warfarin dosing algorithms, 21 algorithms were selected and evaluated using the correlation coefficient (ρ) of actual dose and estimated dose, mean error, and root mean square error.@*RESULTS@#The developed algorithm is as follows: maintenance dose (mg/week)=exp [3.223−0.009×(age)+0.577×(body surface area [BSA])+0.178×(sex)−0.481×(CYP2C9 genotype)+0.227×(VKORC1 genotype)]. Integrated variables explained 44% of the variance in the maintenance dose. The predicted and actual doses showed moderate correlation (ρ=0.641) with the best performance with a mean error of −1.30 mg/week. The proportion of underestimated groups was 17%, which was lower than with the other algorithms.@*CONCLUSIONS@#This is the first study to develop and validate a warfarin dosing algorithm based on data from VKORC1 1173C carriers; it showed superior predictive performance compared with previously published algorithms.

16.
مقالة ي الانجليزية | WPRIM | ID: wpr-764361

الملخص

BACKGROUND AND PURPOSE: The clinical implications of echocardiography findings for long-term outcomes in atrial fibrillation (AF)-related stroke patients are unknown. METHODS: This was a substudy of the Korean ATrial fibrillaTion EvaluatioN regisTry in Ischemic strOke patieNts (K-ATTENTION), which is a multicenter-based cohort comprising prospective stroke registries from 11 tertiary centers. Stroke survivors who underwent two-dimensional transthoracic echocardiography during hospitalization were enrolled. Echocardiography markers included the left-ventricle (LV) ejection fraction (LVEF), the left atrium diameter, and the ratio of the peak transmitral filling velocity to the mean mitral annular velocity during early diastole (E/e′ ratio). LVEF was categorized into normal (≥55%), mildly decreased (>40% and <55%), and severely decreased (≤40%). The E/e′ ratio associated with the LV filling pressure was categorized into normal (<8), borderline (≥8 and <15), and elevated (≥15). Kaplan-Meier and Cox regression analyses were performed for recurrent stroke, major adverse cardiac events, and all-cause death. RESULTS: This study finally included 1,947 patients. Over a median follow-up of 1.65 years (interquartile range, 0.42–2.87 years), the rates of recurrent stroke, major adverse cardiac events, and all-cause death were 35.1, 10.8, and 69.6 cases per 1,000 person-years, respectively. Multivariable analyses demonstrated that severely decreased LVEF was associated with a higher risks of major adverse cardiac events [hazard ratio (HR), 3.91; 95% confidence interval (CI), 1.58–9.69] and all-cause death (HR, 1.95; 95% CI, 1.23–3.10). The multivariable fractional polynomial plot indicated that recurrent stroke might be associated with a lower LVEF. CONCLUSIONS: Severe LV systolic dysfunction could be a determinant of long-term outcomes in AF-related stroke.


الموضوعات
Humans , Atrial Fibrillation , Cohort Studies , Diastole , Echocardiography , Follow-Up Studies , Heart Atria , Hospitalization , Prospective Studies , Registries , Stroke , Survivors
17.
Journal of Stroke ; : 332-339, 2019.
مقالة ي الانجليزية | WPRIM | ID: wpr-766258

الملخص

BACKGROUND AND PURPOSE: To investigate the number and characteristics of patients eligible for endovascular treatment (EVT) determined using three different selection methods: clinical-core mismatch, target mismatch, and collateral status. METHODS: Using the data of consecutive patients from two prospectively maintained registries of university medical centers, the number and characteristics of patients according to the three selection methods were investigated and their correlation was analyzed. Patients with anterior circulation stroke due to occlusion of the middle cerebral and/or internal carotid artery and a National Institute of Health Stroke Scale (NIHSS) score of ≥6 points, who arrived within 8 hours or between 6 and 12 hours of symptom onset and underwent magnetic resonance imaging prior to EVT, were included. Collateral status was assessed using magnetic resonance perfusion-derived collateral flow maps. RESULTS: Three hundred thirty-five patients were investigated; the proportions of patients who were eligible and ineligible for EVT in all three selection methods were both small (n=85, 25.4%; n=54, 16.1%, respectively). The intercorrelation among the three selection methods was low (κ=0.235). The baseline NIHSS score and onset-to-selection time interval were associated with the presence of clinical-core mismatch, while the penumbra/core volume ratio and onset-to-selection time interval were related to target mismatch; none of these variables were associated with collateral status. The infarct core volume was associated with favorable profiles in all three selection methods. CONCLUSIONS: Although the application of individual selection methods resulted in favorable outcomes after EVT in clinical trials, there is a significant discrepancy in EVT eligibility depending on the selection method used.


الموضوعات
Humans , Academic Medical Centers , Carotid Artery, Internal , Magnetic Resonance Imaging , Methods , Prospective Studies , Registries , Stroke
18.
Journal of Stroke ; : 208-217, 2018.
مقالة ي الانجليزية | WPRIM | ID: wpr-714419

الملخص

Intracranial large artery disease (ILAD) is the major cause of stroke worldwide. With the application of recently introduced diagnostic techniques, the prevalence of non-atherosclerotic ILAD is expected to increase. Herein, we reviewed recent reports and summarized progress in the diagnosis and clinical impact of differentiation between ILAD of atherosclerotic and non-atherosclerotic origin. Our review of the literature suggests that more careful consideration of non-atherosclerotic causes and the application of appropriate diagnostic techniques in patients with ILAD may not only provide better results in the treatment of patients, but it may also lead to more successful clinical trials for the treatment of intracranial atherosclerosis.


الموضوعات
Humans , Arteries , Atherosclerosis , Constriction, Pathologic , Diagnosis , Intracranial Arteriosclerosis , Magnetic Resonance Imaging , Prevalence , Stroke
19.
Journal of Stroke ; : 88-96, 2017.
مقالة ي الانجليزية | WPRIM | ID: wpr-121539

الملخص

BACKGROUND AND PURPOSE: Perfusion-diffusion mismatch has been evaluated to determine whether the presence of a target mismatch helps to identify patients who respond favorably to recanalization therapies. We compared the impact on infarct growth of collateral status and the presence of a penumbra, using magnetic resonance perfusion (MRP) techniques. METHODS: Consecutive patients who were candidates for recanalization therapy and underwent serial diffusion-weighted imaging (DWI) and MRP were enrolled. A collateral flow map derived from MRP source data was generated by automatic post-processing. The impact of a target mismatch (Tmax>6 s/apparent diffusion coefficient (ADC) volume≥1.8, ADC volume10 s for ADC volume<100 mL) on infarct growth was compared with MR-based collateral grading on day 7 DWI, using multivariate linear regression analysis. RESULTS: Among 73 patients, 55 (75%) showed a target mismatch, whereas collaterals were poor in 14 (19.2%), intermediate in 36 (49.3%), and good in 23 (31.5%) patients. After adjusting for initial severity of stroke, early recanalization (P<0.001) and the MR-based collateral grading (P=0.001), but not the presence of a target mismatch, were independently associated with infarct growth. Even in patients with a target mismatch and successful recanalization, the degree of infarct growth depended on the collateral status. Perfusion status at later Tmax time points (beyond the arterial phase) was more closely correlated with collateral status. CONCLUSIONS: Patients with good collaterals show a favorable outcome in terms of infarct growth, regardless of the presence of a target mismatch pattern. The presence of slow blood filling predicts collateral status and infarct growth.


الموضوعات
Humans , Collateral Circulation , Diffusion , Linear Models , Magnetic Resonance Imaging , Perfusion , Stroke
20.
Journal of Stroke ; : 77-87, 2017.
مقالة ي الانجليزية | WPRIM | ID: wpr-121540

الملخص

BACKGROUND AND PURPOSE: Patients with active cancer are at an increased risk for stroke. Hypercoagulability plays an important role in cancer-related stroke. We aimed to test whether 1) hypercoagulability is a predictor of survival, and 2) correction of the hypercoagulable state leads to better survival in patients with stroke and active cancer. METHODS: We recruited consecutive patients with acute ischemic stroke and active systemic cancer between January 2006 and July 2015. Hypercoagulability was assessed using plasma D-dimer levels before and after 7 days of anticoagulation treatment. The study outcomes included overall and 1-year survival. Plasma D-dimer levels before and after treatment were tested in univariate and multivariate Cox regression models. We controlled for systemic metastasis, stroke mechanism, age, stroke severity, primary cancer type, histology, and atrial fibrillation using the forward stepwise method. RESULTS: A total of 268 patients were included in the analysis. Patients with high (3rd–4th quartiles) pre-treatment plasma D-dimer levels showed decreased overall and 1-year survival (adjusted HR, 2.19 [95% CI, 1.46–3.31] and 2.70 [1.68–4.35], respectively). After anticoagulation treatment, post-treatment D-dimer level was significantly reduced and independently associated with poor 1-year survival (adjusted HR, 1.03 [95% CI, 1.01–1.05] per 1 μg/mL increase, P=0.015). The successful correction of hypercoagulability was a protective factor for 1-year survival (adjusted HR 0.26 [CI 0.10–0.68], P=0.006). CONCLUSIONS: Hypercoagulability is associated with poor survival after stroke in patients with active cancer. Effective correction of hypercoagulability may play a protective role for survival in these patients.


الموضوعات
Humans , Atrial Fibrillation , Methods , Mortality , Neoplasm Metastasis , Plasma , Prognosis , Protective Factors , Stroke , Thrombophilia
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