Evaluating Rates of Recurrent Ischemic Stroke Among Young Adults With Embolic Stroke of Undetermined Source: The Young ESUS Longitudinal Cohort Study.

Importance: Cryptogenic strokes constitute approximately 40% of ischemic strokes in young adults, and most meet criteria for the embolic stroke of undetermined source (ESUS). Two randomized clinical trials, NAVIGATE ESUS and RESPECT ESUS, showed a high rate of stroke recurrence in older adults with ESUS but the prognosis and prognostic factors among younger individuals with ESUS is uncertain. Objective: To determine rates of and factors associated with recurrent ischemic stroke and death and new-onset atrial fibrillation (AF) among young adults. Design, Setting, and Participants: This multicenter longitudinal cohort study with enrollment from October 2017 to October 2019 and a mean follow-up period of 12 months ending in October 2020 included 41 stroke research centers in 13 countries. Consecutive patients 50 years and younger with a diagnosis of ESUS were included. Of 576 screened, 535 participants were enrolled after 1 withdrew consent, 41 were found to be ineligible, and 2 were excluded for other reasons. The final follow-up visit was completed by 520 patients. Main Outcomes and Measures: Recurrent ischemic stroke and/or death, recurrent ischemic stroke, and prevalence of patent foramen ovale (PFO). Results: The mean (SD) age of participants was 40.4 (7.3) years, and 297 (56%) participants were male. The most frequent vascular risk factors were tobacco use (240 patients [45%]), hypertension (118 patients [22%]), and dyslipidemia (109 patients [20%]). PFO was detected in 177 participants (50%) who had transthoracic echocardiograms with bubble studies. Following initial ESUS, 468 participants (88%) were receiving antiplatelet therapy, and 52 (10%) received anticoagulation. The recurrent ischemic stroke and death rate was 2.19 per 100 patient-years, and the ischemic stroke recurrence rate was 1.9 per 100 patient-years. Of the recurrent strokes, 9 (64%) were ESUS, 2 (14%) were cardioembolic, and 3 (21%) were of other determined cause. AF was detected in 15 participants (2.8%; 95% CI, 1.6-4.6). In multivariate analysis, the following were associated with recurrent ischemic stroke: history of stroke or transient ischemic attack (hazard ratio, 5.3; 95% CI, 1.8-15), presence of diabetes (hazard ratio, 4.4; 95% CI, 1.5-13), and history of coronary artery disease (hazard ratio, 10; 95% CI, 4.8-22). Conclusions and Relevance: In this large cohort of young adult patients with ESUS, there was a relatively low rate of subsequent ischemic stroke and a low frequency of new-onset AF. Most recurrent strokes also met the criteria for ESUS, suggesting the need for future studies to improve our understanding of the underlying stroke mechanism in this population.

Nationwide screening for Fabry disease in unselected stroke patients.

BACKGROUND AND AIMS: Fabry disease (FD) is a rare X-linked lysosomal storage disorder caused by disease-associated variants in the alpha-galactosidase A gene (GLA). FD is a known cause of stroke in younger patients. There are limited data on prevalence of FD and stroke risk in unselected stroke patients. METHODS: A prospective nationwide study including 35 (78%) of all 45 stroke centers and all consecutive stroke patients admitted during three months. Clinical data were collected in the RES-Q database. FD was diagnosed using dried blood spots in a stepwise manner: in males-enzymatic activity, globotriaosylsphingosine (lyso-Gb3) quantification, if positive followed by GLA gene sequencing; and in females GLA sequencing followed by lyso-Gb3. RESULTS: 986 consecutive patients (54% men, mean age 70 years) were included. Observed stroke type was ischemic 79%, transient ischemic attack (TIA) 14%, intracerebral hemorrhage (ICH) 7%, subarachnoid hemorrhage 1% and cerebral venous thrombosis 0.1%. Two (0.2%, 95% CI 0.02-0.7) patients had a pathogenic variant associated with the classical FD phenotype (c.1235_1236delCT and p.G325S). Another fourteen (1.4%, 95% CI 0.08-2.4) patients had a variant of GLA gene considered benign (9 with p.D313Y, one p.A143T, one p.R118C, one p.V199A, one p.R30K and one p.R38G). The index stroke in two carriers of disease-associated variant was ischemic lacunar. In 14 carriers of GLA gene variants 11 strokes were ischemic, two TIA, and one ICH. Patients with positive as compared to negative GLA gene screening were younger (mean 60±SD, min, max, vs 70±SD, min, max, P = 0.02), otherwise there were no differences in other baseline variables. CONCLUSIONS: The prevalence of FD in unselected adult patients with acute stroke is 0.2%. Both patients who had a pathogenic GLA gene variant were younger than 50 years. Our results support FD screening in patients that had a stroke event before 50 years of age.

Gadolinium labelled nanoliposomes as the platform for MRI theranostics: in vitro safety study in liver cells and macrophages.

Gadolinium (Gd)-based contrast agents are extensively used for magnetic resonance imaging (MRI). Liposomes are potential nanocarrier-based biocompatible platforms for development of new generations of MRI diagnostics. Liposomes with Gd-complexes (Gd-lip) co-encapsulated with thrombolytic agents can serve both for imaging and treatment of various pathological states including stroke. In this study, we evaluated nanosafety of Gd-lip containing PE-DTPA chelating Gd+3 prepared by lipid film hydration method. We detected no cytotoxicity of Gd-lip in human liver cells including cancer HepG2, progenitor (non-differentiated) HepaRG, and differentiated HepaRG cells. Furthermore, no potential side effects of Gd-lip were found using a complex system including general biomarkers of toxicity, such as induction of early response genes, oxidative, heat shock and endoplasmic reticulum stress, DNA damage responses, induction of xenobiotic metabolizing enzymes, and changes in sphingolipid metabolism in differentiated HepaRG. Moreover, Gd-lip did not show pro-inflammatory effects, as assessed in an assay based on activation of inflammasome NLRP3 in a model of human macrophages, and release of eicosanoids from HepaRG cells. In conclusion, this in vitro study indicates potential in vivo safety of Gd-lip with respect to hepatotoxicity and immunopathology caused by inflammation.

Risk Factors in Ischemic Stroke Subtypes: A Community-Based Study in Brno, Czech Republic.

BACKGROUND: It is not known if risk factors differ between ischemic stroke (IS) subtypes in Central and Eastern Europe. AIMS: We performed a community-based analysis of risk factors in patients admitted with IS over a 1 year period in Brno, the second largest city in the Czech Republic (CR). METHODS: Based on the National Register of Hospitalized Patients, all patients with IS admitted in Brno in 2011 were identified. Comprehensive discharge summaries from hospital admissions were collected and reviewed. IS subtype and relevant risk factors were ascertained for all patients. The age- and sex-adjusted association of risk factors with IS subtypes was determined. RESULTS: Overall, 682 patients with IS were admitted in 2011 to Brno hospitals. The distribution of IS subtypes was: 35% cardioembolism, 28% large-artery atherosclerosis, 23% small-artery occlusion, 7% stroke of undetermined etiology, 7% stroke of other determined etiology. Several of the risk factors showed high prevalence in the overall sample - e.g. hypertension (84%) and hyperlipidemia (61%). Cardioembolism as compared to other subtypes was positively associated with a history of myocardial infarction, cardiac failure, and atrial fibrillation. Small-artery occlusion was positively associated with history of dementia. No significant association was found between IS subtypes and history of IS, hypertension, diabetes, obesity, alcohol abuse or smoking. CONCLUSIONS: We found high frequency of stroke risk factors in all IS subtypes. These findings have implications for stroke prevention strategies in the CR and across Central Europe.

Evaluation of miRNA detection methods for the analytical characteristic necessary for clinical utilization.

miRNAs are promising biomarkers but methods for their measurement are not clear. We therefore examined three miRNA detection technologies and considered the analytical characteristics essential for clinical utilization. TaqMan assays, SplintR-qPCR and miREIA were compared for their absolute quantification bias, conformity and robustness. Absolute concentrations of miR-142-5p, miR-23a-3p and miR-93-5p were measured with all three methods using 30 samples. Robustness was evaluated by measurement of miR-21-5p in five uniform experiments. Correlations were miRNA-specific, but we observed a different absolute concentration range in RT-qPCR (fmol/µl) and methods evading the RT process (amol/µl). Consistently, RT-less methods reported better robustness (CV 8-19%) than RT-qPCR (CV 39-50%). The calibration curve in TaqMan Advanced assay was influenced by dilution media. Methods avoiding RT seem to be a promising future alternative for miRNA measurement.

Hyaluronic Acid Surface Modified Liposomes Prepared via Orthogonal Aminoxy Coupling: Synthesis of Nontoxic Aminoxylipids Based on Symmetrically α-Branched Fatty Acids, Preparation of Liposomes by Microfluidic Mixing, and Targeting to Cancer Cells Expressing CD44.

New synthetic aminoxy lipids are designed and synthesized as building blocks for the formulation of functionalized nanoliposomes by microfluidization using a NanoAssemblr. Orthogonal binding of hyaluronic acid onto the outer surface of functionalized nanoliposomes via aminoxy coupling ( N-oxy ligation) is achieved at hemiacetal function of hyaluronic acid and the structure of hyaluronic acid-liposomes is visualized by transmission electron microscopy and cryotransmission electron microscopy. Observed structures are in a good correlation with data obtained by dynamic light scattering (size and ζ-potential). In vitro experiments on cell lines expressing CD44 receptors demonstrate selective internalization of fluorochrome-labeled hyaluronic acid-liposomes, while cells with down regulated CD44 receptor levels exhibit very low internalization of hyaluronic acid-liposomes. A method based on microfluidization mixing was developed for preparation of monodispersive unilamellar liposomes containing aminoxy lipids and orthogonal binding of hyaluronic acid onto the liposomal surface was demonstrated. These hyaluronic acid-liposomes represent a potentially new drug delivery platform for CD44-targeted anticancer drugs as well as for immunotherapeutics and vaccines.

Characterization of Patients with Embolic Strokes of Undetermined Source in the NAVIGATE ESUS Randomized Trial.

BACKGROUND: The New Approach Rivaroxaban Inhibition of Factor Xa in a Global Trial vs. ASA to Prevent Embolism in Embolic Stroke of Undetermined Source (NAVIGATE-ESUS) trial is a randomized phase-III trial comparing rivaroxaban versus aspirin in patients with recent ESUS. AIMS: We aimed to describe the baseline characteristics of this large ESUS cohort to explore relationships among key subgroups. METHODS: We enrolled 7213 patients at 459 sites in 31 countries. Prespecified subgroups for primary safety and efficacy analyses included age, sex, race, global region, stroke or transient ischemic attack prior to qualifying event, time to randomization, hypertension, and diabetes mellitus. RESULTS: Mean age was 66.9 ± 9.8 years; 24% were under 60 years. Older patients had more hypertension, coronary disease, and cancer. Strokes in older subjects were more frequently cortical and accompanied by radiographic evidence of prior infarction. Women comprised 38% of participants and were older than men. Patients from East Asia were oldest whereas those from Latin America were youngest. Patients in the Americas more frequently were on aspirin prior to the qualifying stroke. Acute cortical infarction was more common in the United States, Canada, and Western Europe, whereas prior radiographic infarctions were most common in East Asia. Approximately forty-five percent of subjects were enrolled within 30 days of the qualifying stroke, with earliest enrollments in Asia and Eastern Europe. CONCLUSIONS: NAVIGATE-ESUS is the largest randomized trial comparing antithrombotic strategies for secondary stroke prevention in patients with ESUS. The study population encompasses a broad array of patients across multiple continents and these subgroups provide ample opportunities for future research.

Mechanical thrombectomy performs similarly in real world practice: a 2016 nationwide study from the Czech Republic.

BACKGROUND: Randomized clinical trials have proven mechanical thrombectomy (MT) to be a highly effective and safe treatment in acute stroke. The purpose of this study was to compare neurothrombectomy data from the Czech Republic (CR) with data from the HERMES meta-analysis. METHODS: Available nationwide data for the CR from 2016 from the Safe Implementation of Treatments in Stroke-Thrombectomy (SITS-TBY) registry for patients with terminal internal carotid artery (ICA) and/or middle cerebral artery (MCA) occlusions were compared with data from HERMES. CR and HERMES patients were comparable in age, sex, and baseline National Institutes of Health Stroke Scale scores. RESULTS: From a total of 1053 MTs performed in the CR, 845 (80%) were reported in the SITS-TBY. From these, 604 (72%) were included in this study. Occlusion locations were as follows (CR vs HERMES): ICA 22% versus 21% (P=0.16), M1 MCA 62% versus 69% (P=0.004), and M2 MCA 16% versus 8% (P<0.0001). Intravenous thrombolysis was given to 76% versus 83% of patients, respectively (P=0.003). Median onset to reperfusion times were comparable: 232 versus 285 min, respectively (P=0.66). A modified Thrombolysis in Cerebral Infarction score of 2b/3 was achieved in 74% (433/584) versus 71% (390/549) of patients, respectively (OR 1.17, 95% CI 0.90-1.5, P=0.24). There was no statistically significant difference in the percentage of parenchymalhematoma type 2 (OR 1.12, 95% CI 0.66-1.90, P=0.68). A modified Rankin Scale score of 0-2 at 3 months was achieved in 48% (184/268) versus 46% (291/633) of patients, respectively (OR 0.92, 95% CI 0.71-1.18, P=0.48). CONCLUSIONS: Data on efficacy, safety, and logistics of MT from the CR were similar to data from the HERMES collaboration.

Should We Treat a Patient's Symptoms or Angiography Image in TIA?: Two Case Reports.

OBJECTIVES: Data on vascular status in the first hours after onset of transient ischemic attack (TIA) and its clinical significance are missing. Also, it is not known whether arterial occlusion, if present in TIA, should be the target for revascularization. We present 2 patients to demonstrate that TIA can be due to acute major intracranial arterial occlusion and to show how such arterial occlusion may affect the outcome. CASE REPORTS: Two patients (54 and 63 years old) were diagnosed with TIA and at the same time had occlusion of the middle cerebral artery. No recanalization therapy was performed, as there was no or minimal neurological deficit. After several hours, the condition of both patients clinically deteriorated. One patient experienced spontaneous recanalization in the first 24 hours and clinical improvement over the subsequent days, resulting in complete resolution of the neurological deficit. The other patient did not recanalize and developed a significant brain infarction as well as hemorrhagic transformation requiring decompression surgery. Over the long term, the patient remained hemiplegic, unable to walk, and dependent on assistance for most activities of daily living. CONCLUSIONS: The cases presented here raise important questions: (1) How frequently is arterial occlusion present in clinically asymptomatic patients? (2) If occlusion is present but not symptoms, is stroke a more correct diagnosis than TIA? and (3) What would be the benefit of recanalization therapy? Studies addressing these questions should be conducted.

Ipsilateral Sinus Hypoplasia and Poor Leptomeningeal Collaterals as Midline Shift Predictors.

BACKGROUND: We explore the role of dural sinus morphology, leptomeningeal collaterals, and clot localization in the development of malignant brain edema in acute ischemic stroke in anterior circulation. METHODS: This is a single-center retrospective study of consecutive stroke patients with acute occlusion (middle cerebral artery M1 ± intracranial internal carotid artery) treated with intravenous thrombolysis (from November 2009 to November 2014). Admission computed tomography angiography data were evaluated for hypoplasia of dural sinuses, leptomeningeal collaterals, and clot location. Primary outcome was midline shift (<5 mm versus ≥5 mm) on follow-up computed tomography. Secondary outcomes were infarct volume and modified Rankin Scale score of 2 or lower at 90 days. Multivariate logistic regression was used. RESULTS: Of 86 patients (49 females), 36 (42%) had poor collaterals, 26 (30%) had ipsilesional sinus hypoplasia, and 38 (44%) had proximal clots. A midline shift of 5 mm or higher was diagnosed in 14 patients (16%). Infarct volume was larger in the group with midline shift (median: 318 mL [interquartile range {IQR} = 260-350]) than in the group without midline shift (median: 44 mL [IQR = 28-60]) (P = .007). In multivariate analysis, poor leptomeningeal collaterals (odds ratio [OR] = .11, 95% confidence interval [CI] = .03-.44, P = .002 for good collaterals) and ipsilesional sinus hypoplasia (OR = 6.43, 95% CI = 1.5-46.1, P = .008) were independently associated with a midline shift of 5 mm or higher. CONCLUSION: Patients with poor leptomeningeal collaterals and ipsilesional hypoplasia of dural sinuses are more likely to develop midline shift.

Alcohol consumption at midlife and risk of stroke during 43 years of follow-up: cohort and twin analyses.

BACKGROUND AND PURPOSE: Although alcohol-stroke association is well known, the age-varying effect of alcohol drinking at midlife on subsequent stroke risk across older adulthood has not been examined. The effect of genetic/early-life factors is also unknown. We used cohort and twin analyses of data with 43 years of follow-up for stroke incidence to help address these gaps. METHODS: All 11 644 members of the population-based Swedish Twin Registry born 1886 to 1925 with alcohol data aged ≤60 years were included. The interaction of midlife alcohol consumption by age at stroke was evaluated in Cox-regression and analyses of monozygotic twins were used. Covariates were baseline age, sex, cardiovascular diseases, diabetes mellitus, stress reactivity, depression, body mass index, smoking, and exercise. RESULTS: Altogether 29% participants developed stroke. Compared with very-light drinkers (<0.5 drink/d), heavy drinkers (>2 drinks/d) had greater risk of stroke (hazard ratio, 1.34; P=0.02) and the effect for nondrinkers approached significance (hazard ratio, 1.11; P=0.08). Age increased stroke risk for nondrinkers (P=0.012) and decreased it for heavy drinkers (P=0.040). Midlife heavy drinkers were at high risk from baseline until the age of 75 years when hypertension and diabetes mellitus grew to being the more relevant risk factors. In analyses of monozygotic twin-pairs, heavy drinking shortened time to stroke by 5 years (P=0.04). CONCLUSIONS: Stroke-risk associated with heavy drinking (>2 drinks/d) in midlife seems to predominate over well-known risk factors, hypertension and diabetes, until the age of ≈75 years and may shorten time to stroke by 5 years above and beyond covariates and genetic/early-life factors. Alcohol consumption should be considered an age-varying risk factor for stroke.

Predictors of noticing stroke educational campaign.

BACKGROUND: Long-term campaigns to improve stroke awareness, such as the campaign conducted in the Czech Republic since 2006, have not been effective. However, the small subpopulation that noticed the campaign had better stroke awareness than the population that did not. To better understand this awareness campaign responsiveness and to design more successful future campaigns, predictors of noticing campaigns were identified. MATERIALS AND METHODS: This study is a secondary analysis of cross-sectional nationwide survey data of the Czech population older than 40 years, collected in 2009. The survey used a 3-stage random sampling method (area, household, and household member) and personal semistructured interview questionnaires concerning participants' stroke knowledge, demographic characteristics, medical history, and stroke information sources. To identify the association between these variables and whether the campaign was noticed (the primary outcome of the study), multivariate binary logistic regression analysis was used. RESULTS: A total of 601 participants were surveyed (90% response rate), 19% of them stated that they noticed the stroke awareness campaign. Primary independent predictors of campaign efficiency were heart disease (odds ratio [OR], 1.8; 95% confidence interval [CI], 1.0-3.2), obesity (OR, 2.4; 95% CI, 1.3-4.7), and current smoking (OR, .4; 95% CI, .3-.7). CONCLUSIONS: Tobacco smokers in particular should be targeted by stroke awareness campaigns, for example, through health warning labels on cigarette packs. People with some stroke risk factors, such as heart disease and obesity, are responsive to information about stroke. Therefore, educational campaigns should target the groups with increased risk of stroke.

Decompressive surgery for malignant supratentorial infarction remains underutilized after guideline publication.

Decompressive surgery <48 h from stroke onset reduces the prevalence of mortality and morbidity from malignant supratentorial infarction. We investigated if utilization of decompressive surgery changed in the Czech Republic (CZ) after the release of new guidelines regarding treatment of malignant brain infarction. The volume of decompressive surgery in 2009 in all centers in the CZ was assessed using the same methodology as in 2006. All neurosurgery departments in the CZ were asked to complete a questionnaire and asked to identify all cases of decompressive surgery for malignant brain infarction through a combination of discharge codes for "brain infarction" and "decompressive surgery" from electronic hospital charts. Data for 56 patients were obtained from 15 of the 16 neurosurgery departments in the CZ. The average age was 53 ± 13; number of males 20; median time to surgery was 48 h (range 24-62); median NIHSS score was 25 (IQR, 20-30); median infarct volume was 300 cm(3) [interquartile (IQR, 250-350)]; mean shift on CT was 10.6 ± 3.6 mm and size of hemicraniectomy was 125 cm(2) (IQR, 110-154). A favorable outcome was achieved in 45% of the patients. The number of procedures increased from 39 in 2,006 to 2,056 in 2009. Based on data from one stroke center, 10% suffered from malignant supratentorial infarction and 2.3% met the criteria for decompressive surgery. In 2009, as compared to 2006, the volume of decompressive surgery carried out moderately increased. However, procedures remained underutilized because only ~10% of those who needed decompressive surgery underwent surgery.

Nationwide study of decompressive surgery for malignant supratentorial infarction in the Czech Republic: utilization and outcome predictors. Clinical article.

OBJECT: Decompressive surgery within 48 hours in patients younger than 60 years of age reduces mortality and morbidity from malignant supratentorial infarction. The goal of this study was to characterize the utilization of decompressive surgery in the Czech Republic in 2006. METHODS: This nationwide study was undertaken from September to December 2007 using a questionnaire sent to all neurosurgery departments in the Czech Republic. Diagnosis of brain infarction and decompressive surgery was based on discharge codes. Patient data were retrieved from hospital charts. Favorable outcome was defined as a modified Rankin scale score ≤4 on the day of discharge from the hospital. RESULTS: Data were obtained from 15 of the 16 neurosurgery departments in the Czech Republic (94%) and from 39 patients (11 female [28%]). The average patient age was 52 +/-14 years (11 patients > 60), median time to surgery was 48 hours (interquartile range [IQR] 26-67 hours; 15 patients > 48 hours), median National Institutes of Health Stroke Scale score was 22 (IQR 16-30), median infarct volume was 341 cm³ (IQR 243-375 cm³), mean shift from the midline was 9.9 +/- 4.1 mm, median duration of hospitalization was 19 days (IQR 13-30 days), and mean bone flap surface area was 75 cm² (IQR 70-97 cm²). A favorable outcome was achieved in 19 patients (49%). The median number of procedures per site in 2006 was 1.5 (range 0-13 procedures). Five sites (31%) serving one-third of the entire population did not perform any decompressive surgery. No variable was a significant predictor of outcome in a multiple regression model. CONCLUSIONS: In 2006 decompressive surgery was underutilized and occurred late in the clinical course in the Czech Republic. Revision of national guidelines is necessary to incorporate the latest data and ensure that the patients who can benefit most receive treatment.