Hypothyroidism's effect on stroke limited to specific subtypes: A Mendelian randomization study.

BACKGROUND: The association between hypothyroidism and stroke remains controversial and the association between hypothyroidism and stroke subtypes has not been satisfactorily researched. This study aimed to explore the causal effect of hypothyroidism on the risk of stroke and its subtypes by Mendelian randomization (MR) analysis. METHODS: Single nucleotide polymorphisms (SNPs) were selected from published genome-wide association studies (GWAS) meta-analysis as instrumental variables (IVs) for hypothyroidism. As outcomes, summary GWAS data for stroke and its subtypes were obtained from two other large GWAS meta-analyses, including any stroke (AS), any ischemic stroke (AIS), large vessel stroke (LAS), cardiogenic embolic stroke (CES), small vessel stroke (SVS), and intracranial hemorrhage (ICH). Univariate Mendelian randomization (UVMR) and multivariate Mendelian randomization (MVMR) were used to assess the causal effect of hypothyroidism on stroke and its subtypes. RESULTS: In UVMR, genetically predicted hypothyroidism was significantly associated with LAS (OR = 1.14, 95CI = 1.02-1.27) and SVS (OR = 1.14, 95CI = 1.04-1.25), but not with AS, AIS, CES, and ICH. The results of the MVMR showed that after adjusting for smoking, alcohol consumption, hypertension, diabetes, low-density lipoprotein cholesterol (LDL-c), and body mass index (BMI), the causal association between hypothyroidism and SVS remained significant, while the association between hypothyroidism and LAS became nonsignificant. CONCLUSION: Hypothyroidism is causally associated with risk for LAS and SVS, but not for other stroke subtypes. Hypothyroidism may be an independent risk factor for SVS, and vascular risk factors play an important role in hypothyroidism causing LAS.

Clinical and Genetic Atrial Fibrillation Risk and Discrimination of Cardioembolic From Noncardioembolic Stroke.

BACKGROUND: Stroke is a leading cause of death and disability worldwide. Atrial fibrillation (AF) is a common cause of stroke but may not be detectable at the time of stroke. We hypothesized that an AF polygenic risk score (PRS) can discriminate between cardioembolic stroke and noncardioembolic strokes. METHODS: We evaluated AF and stroke risk in 26 145 individuals of European descent from the Stroke Genetics Network case-control study. AF genetic risk was estimated using 3 recently developed PRS methods (LDpred-funct-inf, sBayesR, and PRS-CS) and 2 previously validated PRSs. We performed logistic regression of each AF PRS on AF status and separately cardioembolic stroke, adjusting for clinical risk score (CRS), imputation group, and principal components. We calculated model discrimination of AF and cardioembolic stroke using the concordance statistic (c-statistic) and compared c-statistics using 2000-iteration bootstrapping. We also assessed reclassification of cardioembolic stroke with the addition of PRS to either CRS or a modified CHA2DS2-VASc score alone. RESULTS: Each AF PRS was significantly associated with AF and with cardioembolic stroke after adjustment for CRS. Addition of each AF PRS significantly improved discrimination as compared with CRS alone (P<0.01). When combined with the CRS, both PRS-CS and LDpred scores discriminated both AF and cardioembolic stroke (c-statistic 0.84 for AF; 0.74 for cardioembolic stroke) better than 3 other PRS scores (P<0.01). Using PRS-CS PRS and CRS in combination resulted in more appropriate reclassification of stroke events as compared with CRS alone (event reclassification [net reclassification indices]+=14% [95% CI, 10%-18%]; nonevent reclassification [net reclassification indices]-=17% [95% CI, 15%-0.19%]) or the modified CHA2DS2-VASc score (net reclassification indices+=11% [95% CI, 7%-15%]; net reclassification indices-=14% [95% CI, 12%-16%]) alone. CONCLUSIONS: Addition of polygenic risk of AF to clinical risk factors modestly improves the discrimination of cardioembolic from noncardioembolic strokes, as well as reclassification of stroke subtype. Polygenic risk of AF may be a useful biomarker for identifying strokes caused by AF.

Potential Embolic Sources in Embolic Stroke of Undetermined Source Patients with Patent Foramen Ovale.

INTRODUCTION: A patent foramen ovale (PFO) may coexist with other potential embolic sources (PESs) in patients with embolic stroke of undetermined source (ESUS), leading to difficulty in attributing the stroke to either the PFO or other PESs. We aimed to investigate the prevalence and predictors of concomitant PESs in ESUS patients with PFOs. METHODS: A retrospective cohort study was conducted in a tertiary stroke centre. Consecutive patients with ESUS and a concomitant PFO admitted between 2012 and 2021 were included in the study. Baseline characteristics and investigations as a part of stroke workup including echocardiographic and neuroimaging data were collected. PESs were adjudicated by 2 independent neurologists after reviewing the relevant workup. RESULTS: Out of 1,487 ESUS patients, a total of 309 patients who had a concomitant PFO with mean age of 48.8 ± 13.2 years were identified during the study period. The median Risk of Paradoxical Embolism (RoPE) score for the study cohort was 6 (IQR 5-7.5). Of the 309 patients, 154 (49.8%) only had PFO, 105 (34.0%) patients had 1 other PES, 34 (11.0%) had 2 PES, and 16 (5.2%) had 3 or more PES. The most common PESs were atrial cardiopathy (23.9%), left ventricular dysfunction (22.0%), and cardiac valve disease (12.9%). The presence of additional PESs was associated with age ≥60 years (p < 0.001), RoPE score ≤6 (p ≤0.001), and the presence of comorbidities including diabetes mellitus (p = 0.004), hypertension (p≤ 0.001), and ischaemic heart disease (p = 0.011). CONCLUSION: A large proportion of ESUS patients with PFOs had concomitant PESs. The presence of concomitant PESs was associated with older age and a lower RoPE score. Further, large cohort studies are warranted to investigate the significance of the PES and their overlap with PFOs in ESUS.

Predictors of Atrial Fibrillation Development in Patients With Embolic Stroke of Undetermined Source: An Analysis of the RE-SPECT ESUS Trial.

BACKGROUND: A proportion of patients with embolic stroke of undetermined source have silent atrial fibrillation (AF) or develop AF after the initial evaluation. Better understanding of the risk for development of AF is critical to implement optimal monitoring strategies with the goal of preventing recurrent stroke attributable to underlying AF. The RE-SPECT ESUS trial (Randomized, Double-Blind Evaluation in Secondary Stroke Prevention Comparing the Efficacy and Safety of the Oral Thrombin Inhibitor Dabigatran Etexilate Versus Acetylsalicylic Acid in Patients With Embolic Stroke of Undetermined Source) provides an opportunity to assess predictors for developing AF and associated recurrent stroke. METHODS: RE-SPECT ESUS was a randomized, controlled trial (564 sites, 42 countries) assessing dabigatran versus aspirin for the prevention of recurrent stroke in patients with embolic stroke of undetermined source. Of 5390 patients enrolled and followed for a median of 19 months, 403 (7.5%) were found to develop AF reported as an adverse event or using cardiac monitoring per standard clinical care. Univariable and multivariable regression analyses were performed to define predictors of AF. RESULTS: In the multivariable model, older age (odds ratio for 10-year increase, 1.99 [95% CI, 1.78-2.23]; P<0.001), hypertension (odds ratio, 1.36 [95% CI, 1.03-1.79]; P=0.0304), diabetes (odds ratio, 0.74 [95% CI, 0.56-0.96]; P=0.022), and body mass index (odds ratio for 5-U increase, 1.29 [95% CI, 1.16-1.43]; P<0.001) were independent predictors of AF during the study. In a sensitivity analysis restricted to 1117 patients with baseline NT-proBNP (N-terminal prohormone of brain natriuretic peptide) measurements, only older age and higher NT-proBNP were significant independent predictors of AF. Performance of several published predictive models was assessed, including HAVOC (AF risk score based on hypertension, age ≥75 years, valvular heart disease, peripheral vascular disease, obesity, congestive heart failure, and coronary artery disease) and CHA2DS2-VASc (stroke risk score based on congestive heart failure, hypertension, age ≥75 years [doubled], diabetes, previous stroke, transient ischemic attack or thromboembolism [doubled], vascular disease, age 65 to 74 years, and sex category [female]) scores, and higher scores were associated with higher rates of developing AF. CONCLUSIONS: Besides age, the most important variable, several other factors, including hypertension, higher body mass index, and lack of diabetes, are independent predictors of AF after embolic stroke of undetermined source. When baseline NT-proBNP was available, only older age and elevation of this biomarker were predictive of subsequent AF. Understanding who is at higher risk of developing AF will assist in identifying patients who may benefit from more intense, long-term cardiac monitoring. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02239120.

Transdermal oestradiol for androgen suppression in prostate cancer: long-term cardiovascular outcomes from the randomised Prostate Adenocarcinoma Transcutaneous Hormone (PATCH) trial programme.

BACKGROUND: Androgen suppression is a central component of prostate cancer management but causes substantial long-term toxicity. Transdermal administration of oestradiol (tE2) circumvents first-pass hepatic metabolism and, therefore, should avoid the cardiovascular toxicity seen with oral oestrogen and the oestrogen-depletion effects seen with luteinising hormone releasing hormone agonists (LHRHa). We present long-term cardiovascular follow-up data from the Prostate Adenocarcinoma Transcutaneous Hormone (PATCH) trial programme. METHODS: PATCH is a seamless phase 2/3, randomised, multicentre trial programme at 52 study sites in the UK. Men with locally advanced or metastatic prostate cancer were randomly allocated (1:2 from August, 2007 then 1:1 from February, 2011) to either LHRHa according to local practice or tE2 patches (four 100 µg patches per 24 h, changed twice weekly, reducing to three patches twice weekly if castrate at 4 weeks [defined as testosterone ≤1·7 nmol/L]). Randomisation was done using a computer-based minimisation algorithm and was stratified by several factors, including disease stage, age, smoking status, and family history of cardiac disease. The primary outcome of this analysis was cardiovascular morbidity and mortality. Cardiovascular events, including heart failure, acute coronary syndrome, thromboembolic stroke, and other thromboembolic events, were confirmed using predefined criteria and source data. Sudden or unexpected deaths were attributed to a cardiovascular category if a confirmatory post-mortem report was available and as other relevant events if no post-mortem report was available. PATCH is registered with the ISRCTN registry, ISRCTN70406718; the study is ongoing and adaptive. FINDINGS: Between Aug 14, 2007, and July 30, 2019, 1694 men were randomly allocated either LHRHa (n=790) or tE2 patches (n=904). Overall, median follow-up was 3·9 (IQR 2·4-7·0) years. Respective castration rates at 1 month and 3 months were 65% and 93% among patients assigned LHRHa and 83% and 93% among those allocated tE2. 157 events from 145 men met predefined cardiovascular criteria, with a further ten sudden deaths with no post-mortem report (total 167 events in 153 men). 26 (2%) of 1694 patients had fatal cardiovascular events, 15 (2%) of 790 assigned LHRHa and 11 (1%) of 904 allocated tE2. The time to first cardiovascular event did not differ between treatments (hazard ratio 1·11, 95% CI 0·80-1·53; p=0·54 [including sudden deaths without post-mortem report]; 1·20, 0·86-1·68; p=0·29 [confirmed group only]). 30 (34%) of 89 cardiovascular events in patients assigned tE2 occurred more than 3 months after tE2 was stopped or changed to LHRHa. The most frequent adverse events were gynaecomastia (all grades), with 279 (38%) events in 730 patients who received LHRHa versus 690 (86%) in 807 patients who received tE2 (p<0·0001) and hot flushes (all grades) in 628 (86%) of those who received LHRHa versus 280 (35%) who received tE2 (p<0·0001). INTERPRETATION: Long-term data comparing tE2 patches with LHRHa show no evidence of a difference between treatments in cardiovascular mortality or morbidity. Oestrogens administered transdermally should be reconsidered for androgen suppression in the management of prostate cancer. FUNDING: Cancer Research UK, and Medical Research Council Clinical Trials Unit at University College London.

Risk Factors, and Clinical and Etiological Characteristics of Ischemic Strokes in COVID-19-Infected Patients: A Systematic Review of Literature.

BACKGROUND AND PURPOSE: Coronavirus disease 2019 (CO-VID-19) infection is an ongoing pandemic and worldwide health emergency that has caused important changes in healthcare systems. Previous studies reported an increased risk of thromboembolic events, including stroke. This systematic review aims to describe the clinical features and etiological characteristics of ischemic stroke patients with CO-VID-19 infection. METHOD: A literature search was performed in principal databases for studies and case reports containing data concerning risk factors, clinical features, and etiological characteristics of patients infected with COVID-19 and suffering from stroke. Descriptive and analytical statistics were applied. RESULTS: Overall, 14 articles were included for a total of 93 patients. Median age was 65 (IQR: 55-75) years with prevalence in males. Stroke occurred after a median of 6 days from COVID-19 infection diagnosis. Median National of Institute of Health Stroke Scale (NIHSS) score was 19. Cryptogenic (Cry) strokes were more frequent (51.8%), followed by cardioembolic etiology, and they occurred a long time after COVID-19 diagnosis compared with large-artery atherosclerosis strokes (ptrend: 0.03). The clinical severity of stroke was significantly associated with the severity grade of COVID-19 infection (ptrend: 0.03). CONCLUSIONS: Ischemic strokes in COVID-19-infected patients were clinically severe, affecting younger patients mainly with Cry and cardioembolic etiologies. Further multicenter prospective registries are needed to better describe the causal association and the effect of COVID-19 infection on stroke.

Incidence of Stroke and Ischemic Stroke Subtypes: A Community-Based Study in Brno, Czech Republic.

BACKGROUND: There are few contemporary epidemiological data on stroke for Central Europe. We performed a population-based study evaluating the incidence of stroke, stroke types, and ischemic stroke (IS) subtypes in Brno, the second biggest city in the Czech Republic (CR). METHODS: Using the National Registry of Hospitalized Patients, and hospital databases, we identified all patients hospitalized with a stroke diagnosis in Brno hospitals in 2011. For Brno residents with validated stroke diagnosis, we calculated (a) the overall incidence of hospitalized stroke, (b) incidence rates for IS, subarachnoid hemorrhage (SAH) and intracerebral hemorrhage (ICH), and (c) incidence rates for IS subtypes. We calculated the average annual age- and sex-standardized incidence (European Standard Population and World Health Organization), to compare our results with other studies. RESULTS: The overall crude incidence of stroke in Brno was 213/100,000 population. The incidence of stroke for stroke types were as follows: SAH, 6.9; ICH, 26.4; and IS, 180 cases per 100,000 population, respectively. The WHO-standardized annual stroke incidence was 107 for all strokes and 88 for IS, 14.4 for ICH, and 5 for SAH. For IS subtypes, the WHO-standardized incidence was large artery atherosclerosis 25.8, cardioembolism 27.8, lacunar 21.6, other determined etiology 6.2, and undetermined etiology 6.5 cases per 100,000 population. CONCLUSIONS: The stroke incidence is lower than that previously reported for the CR and Eastern Europe probably reflecting socioeconomic changes in post-communistic countries in the region. These findings could contribute to stroke prevention strategies and influence health policies.

Appropriateness of the Direct Oral Anticoagulants Dosing in the Middle East Gulf Region.

ABSTRACT: Direct oral anticoagulants (DOACs) have proven efficacy to prevent cardioembolic strokes. Data are scarce about the appropriateness of DOAC dosing in the Middle East. We investigated the prevalence of inappropriate DOAC dosing in the region. A cross-sectional study was conducted at our hospital between April 2015 and February 2019 of patients receiving 1 of the 3 available DOACs. Patients with incomplete data sets, those prescribed DOACs for indications other than atrial fibrillation, on DOACs for <30 days, and dialysis patients were excluded. A total of 608 met the inclusion criteria. The mean age was 65.2 ± 13.9 years, and most were men (58.6%). The mean CHA2DS2-VASc score was 3.8 ± 2.0. There were 346 (56.9%) on apixaban, 123 (20.2%) on dabigatran, and 139 (22.9%) on rivaroxaban. The logistic regression model showed that for the 3 agents together, age, eGFR, major bleeding history, and history of prior stroke were significantly associated with the decision to inappropriately underdose (P < 0.05). Fifteen patients had an ischemic stroke after apixaban initiation (5 underdosed and 3 overdosed). Among patients with at least one follow-up encounter, major bleeding occurred in 13 patients (11.7%) with inappropriate dosing compared with 29 patients (6.0%) with appropriate dosing (P = 0.04). Ischemic stroke occurred in 11 patients (9.9%) with inappropriate dosing compared with 15 patients (3.1%) with appropriate dosing (P < 0.01). We concluded that inappropriate DOAC underdosing is common in our region, particularly with apixaban and rivaroxaban. It is associated with increased risk of stroke and bleeding. More education targeting prescribers is needed to encourage adherence to standard dosing criteria.

Burden of oral anticoagulation in embolic stroke of undetermined source without atrial fibrillation.

OBJECTIVE: Prevention of recurrent stroke in patients with embolic stroke of undetermined source (ESUS) is challenging. The advent of safer anticoagulation in the form of direct oral anticoagulants (DOACs) has prompted exploration of prophylactic anticoagulation for all ESUS patients, rather than anticoagulating just those with documented atrial fibrillation (AF). However, recent trials have failed to demonstrate a clinical benefit, while observing increased bleeding. We modeled the economic impact of anticoagulating ESUS patients without documented AF across multiple geographies. METHODS: CRYSTAL-AF trial data were used to assess ischaemic stroke event rates in ESUS patients confirmed AF-free after long-term monitoring. Anticipated bleeding event rates (including both minor and major bleeds) with aspirin, dabigatran 150 mg, and rivaroxaban 20 mg were sourced from published meta-analyses, whilst a 30% ischaemic stroke reduction for both DOACs was assumed. Cost data for clinical events and pharmaceuticals were collected from the local payer perspective. RESULTS: Compared with aspirin, dabigatran and rivaroxaban resulted in 17.9 and 29.9 additional bleeding events per 100 patients over a patient's lifetime, respectively. Despite incorporating into our model the proposed 30% reduction in ischaemic stroke risk, both DOACs were cost-additive over patient lifetime, as the costs of bleeding events and pharmaceuticals outweighed cost savings associated with the reduction in ischaemic strokes. DOACs added £5953-£7018 per patient (UK), €6683-€7368 (Netherlands), €4933-€9378 (Spain), AUD$5353-6539 (Australia) and $26,768-$32,259 (US) of payer cost depending on the agent prescribed. Additionally, in the U.S. patient pharmacy co-payments ranged from $2468-$12,844 depending on agent and patient plan. In all settings, cost-savings could not be demonstrated even when the modelling assumed 100% protection from recurrent ischaemic strokes, due to the very low underlying risk of recurrent ischaemic stroke in this population (1.27 per 100 patient-years). CONCLUSIONS: Anticoagulation of non-AF patients may cause excess bleeds and add substantial costs for uncertain benefits, suggesting a personalised approach to anticoagulation in ESUS patients.

The efficacy and safety of Hirudin plus Aspirin versus Warfarin in the secondary prevention of Cardioembolic Stroke due to Nonvalvular Atrial Fibrillation: A multicenter prospective cohort study.

Background: To investigate the efficacy and safety of hirudin plus aspirin therapy compared with warfarin in the secondary prevention of cardioembolic stroke due to nonvalvular atrial fibrillation (NVAF). Methods: Patients with cardioembolic stroke due to NVAF were prospectively enrolled from 18 collaborating hospitals from Dec 2011 to June 2015. Fourteen days after stroke onset, eligible patients were assigned to the hirudin plus aspirin group (natural hirudin prescribed as the traditional Chinese medicine Maixuekang capsule, 0.75 g, three times daily, combined with aspirin 100 mg, once daily) or the warfarin group (dose-adjusted warfarin targeting international normalized ratio (INR) 2-3, with an initial daily dose of 1.25 mg). Patients were followed up at 1, 2, 3, 6, 9, and 12 months after stroke onset. Time in therapeutic range (TTR) was calculated according to Rosendaal methodology to evaluate the quality of INR management in the warfarin group. The primary efficacy endpoint was the recurrence of stroke within 12 months after stroke onset. Safety was assessed as the occurrence of the composite event "intracranial hemorrhage and other bleeding events, death, and other serious adverse events". The Cox proportional hazard model and Kaplan-Meier curve were used to analyze the efficacy and safety events. Results: A total of 221 patients entered final analysis with 112 patients in the hirudin plus aspirin group and 109 in the warfarin group. Over the whole duration of our study, TTR for patients taking warfarin was 66.5 % ± 21.5%. A significant difference was not observed in the recurrence of stroke between the two groups (3.57% vs. 2.75%; P = 0.728). The occurrence of safety events was significantly lower in the hirudin plus aspirin group (2.68% vs.10.09%; P = 0.024). The risk for efficacy event was similar between the two groups (hazard ratio (HR), 1.30; 95% confidence interval (CI), 0.29-5.80). The safety risk was significantly lower in the hirudin plus aspirin group (HR, 0.27; 95% CI, 0.07-0.95). Kaplan-Meier analysis revealed significant difference in the temporal distribution in safety events (P = 0.023) but not in stroke recurrence (P = 0.726). Conclusion: Significant difference in efficacy was not detected between warfarin group and hirudin plus aspirin group. Compared with warfarin, hirudin plus aspirin therapy had lower safety risk in the secondary prevention of cardioembolic stroke due to NVAF.

Carotid Atherosclerosis and Patent Foramen Ovale in Embolic Stroke of Undetermined Source.

BACKGROUND: Carotid atherosclerosis and likely pathogenic patent foramen ovale (PFO) are two potential embolic sources in patients with embolic stroke of undetermined source (ESUS). The relationship between these two mechanisms among ESUS patients remains unclear. AIM: To investigate the relation between carotid atherosclerosis and likely pathogenic PFO in patients with ESUS. We hypothesized that ipsilateral carotid atherosclerotic plaques are less prevalent in ESUS with likely pathogenic PFO compared to patients with likely incidental PFO or without PFO. METHODS: The presence of PFO was assessed with transthoracic echocardiography with microbubble test and, when deemed necessary, through trans-oesophageal echocardiography. The presence of PFO was considered as likely incidental if the RoPE (Risk of Paradoxical Embolism) score was 0-6 and likely pathogenic if 7-10. RESULTS: Among 374 ESUS patients (median age: 61years, 40.4% women), there were 63 (49.6%) with likely incidental PFO, 64 (50.4%) with likely pathogenic PFO and 165 (44.1%) with ipsilateral carotid atherosclerosis. The prevalence of ipsilateral carotid atherosclerosis was lower in patients with likely pathogenic PFO (7.8%) compared to patients with likely incidental PFO (46.0%) or patients without PFO (53.0%) (p<0.001). After adjustment for multiple confounders, the prevalence of ipsilateral carotid atherosclerosis remained lower in patients with likely pathogenic PFO compared to patients with likely incidental PFO or without PFO (adjusted OR=0.32, 95%CI:0.104-0.994, p=0.049). CONCLUSIONS: The presence of carotid atherosclerosis is inversely related to the presence of likely pathogenic PFO in patients with ESUS.

Detection of Myocardial Infarction by Cardiac Magnetic Resonance in Embolic Stroke Related to First Diagnosed Atrial Fibrillation.

INTRODUCTION: Elevated troponin levels are found in a significant number of patients who are diagnosed with acute embolic stroke (AES) after first diagnosed atrial fibrillation (AF). These myocardial injuries, which are known as cardiocerebral infarction (CCI), are potentially caused by coronary embolism and correspond to simultaneous cardiac and cerebral embolisms. However, this severe condition remains poorly understood. In this prospective study, we aimed to investigate the prevalence and the cardiac magnetic resonance (CMR) characteristics of CCI. MATERIALS AND METHODS: Consecutive patients with first diagnosed AF hospitalized for AES in a neurovascular intensive care unit from 2019 to 2020 were included. Troponin Ic kinetic were measured <72 h, MRI and coronary angiography or CT scan were performed <7 days after admission. Patients with significant coronary lesions were excluded. RESULTS: During the study period, 1150 patients with strokes were hospitalized in the neurovascular intensive care unit (ICU). Of these patients, 955 had an ischemic stroke and 97 had a transient ischemic attack. Among the 44 patients with AES and with first diagnosed AF, 34 patients underwent CMR and CMR analysis identified 12 MI. A significant rise in troponin (>0.10 µg/L) was observed in 35% of the total population (12/34 patients). More specifically, a rise was seen in 23% of the AES without MI group, 58% of the AES with MI. In addition, coronary embolism was identified in 3 patients who underwent coronary angiography (3/12) and MI was often (30%) localized in infero-latero-medial and infero-apical segments. Most AES were localized in the superficial sylvian territory. CONCLUSION: We found a high prevalence of CMR-confirmed double embolization sites in the acute phase of an embolic stroke. Further studies are required to better characterize the pathophysiology, clinical course and prognostic value of CCI. Moreover, optimal management strategies, including antiplatelet therapy, remain to be determined.

Recurrent Ischemic Stroke - A Systematic Review and Meta-Analysis.

OBJECTIVES: Recurrent stroke remains a challenge though secondary prevention is initiated immediately post-stroke. Stroke subtype may determine the risk of recurrent stroke and require specific preventive measures. We aimed to identify subtype-specific stroke recurrence and associated risk factors over time. METHODS AND MATERIALS: A systematic review was performed using PubMed and Embase for studies including adults >18 years, first-ever ischemic stroke in population-based observational studies or registries, documented TOAST-criteria and minimum 1-year follow-up. Meta-analysis on stroke recurrence rate was performed. Final search: November 2019. RESULTS: The search retrieved 26 studies (between 1997 and 2019). Stroke recurrence rate ranged from 5.7% to 51.3%. Recurrent stroke was most frequent in large artery atherosclerosis (LAA) and cardioembolic (CE) stroke with recurrent stroke similar to index stroke subtype. We identified a lower recurrence rate for small vessel occlusion (SVO) stroke with recurrence frequently of another stroke subtype. Based on a meta-analysis the summary proportion recurrence rate of recurrent stroke in studies using TOAST-criteria = 0.12 and = 0.14 in studies using TOAST-like criteria. Hypertension, diabetes mellitus, atrial fibrillation previous transient ischemic attack, and high stroke severity were independent risk factors for recurrence. CONCLUSION: Stroke recurrence rates seem unchanged over time despite the use of secondary prevention. The highest recurrence rate is in LAA and CE stroke eliciting same subtype recurrent stroke. A lower recurrence rate is seen with SVO stroke with a more diverse recurrence pattern. Extensive workup is important in all stroke subtypes - including SVO stroke. Future research needs to identify better preventive treatment and improve compliance to risk factor prevention to reduce stroke recurrence.

Trends, Predictors and Outcomes of Ischemic Stroke Among Patients Hospitalized with Takotsubo Cardiomyopathy.

OBJECTIVES: This study assessed the temporal trends in the incidence of ischemic stroke among patients hospitalized with takotsubo cardiomyopathy (TCM) stratified by the subtypes of ischemic stroke (cardioembolic versus thrombotic). Predictors of each stroke subtype, the association with atrial fibrillation (AF), the occurrence of ventricular fibrillation/ventricular tachycardia (VF/VT), cardiogenic shock (CS), in-hospital mortality, length of stay (LOS), and total healthcare cost were also assessed. BACKGROUND: Ischemic stroke in TCM is thought to be primarily cardioembolic from left ventricular mural thromboembolism. Limited data are available on the incidence of thrombotic ischemic stroke in TCM. MATERIALS AND METHODS: We identified 27,970 patients hospitalized with the primary diagnosis of TCM from the 2008 to 2017 National Inpatient Sample, of which 751 (3%) developed ischemic stroke. Of those with ischemic stroke, 571 (76%) had thrombotic stroke while 180 (24%) had cardioembolic stroke. Cochrane armitage test was used to assess the incidence of thrombotic and cardioembolic strokes and multivariate regression was used to identify risk factors associated with each stroke subtype. We compared the incidence of AF, VF/VT, CS, LOS, in-hospital mortality and total cost between hospitalized patients with TCM alone to those with cardioembolic and thrombotic strokes. RESULTS: From 2008 - 2017, the incidence of thrombotic stroke (4.7%-9.5% (p< 0.0001) increased while it was unchanged for cardioembolic stroke (0.5%-0.7% P=0.5). In the multivariate regression, peripheral artery disease, prior history of stroke, and hyperlipidemia were significantly associated with thrombotic stroke, while CS, AF, and Asian race (compared to White race) were associated with cardioembolic stroke. Both cardioembolic and thrombotic strokes were associated with higher odds of IHM, AF, CS, longer LOS and increased cost. Trends in in-hospital mortality and the utilization of thrombolysis, cerebral angiography, and mechanical thrombectomy among patients with TCM and ischemic stroke were unchanged from 2008 to 2017. CONCLUSION: Among patients with TCM and ischemic stroke, thrombotic stroke was more common compared to cardioembolic stroke. Ischemic stroke was associated with poorer outcomes, including higher in-hospital mortality and increased healthcare resource utilization in TCM.

Microbleeds and Outcome in Patients With Acute Ischemic Stroke and Atrial Fibrillation Taking Anticoagulants.

BACKGROUND AND PURPOSE: We investigated the impact of the presence, burden, and location of cerebral microbleeds (CMBs) on the risk of major adverse cerebrovascular and cardiovascular events (MACCE) in patients with acute ischemic stroke and atrial fibrillation treated with oral anticoagulants (OACs). We also examined whether the clinical effect of CMBs differs according to the type of OACs. METHODS: A total of 1742 patients with acute ischemic stroke and atrial fibrillation treated with OACs were enrolled in this cohort study. The primary composite outcome was the occurrence of MACCE (a composite of stroke, acute myocardial infarction, or vascular death) over a 2-year period according to CMB status. RESULTS: CMB presence was significantly associated with the risk of future MACCE (hazard ratio, 1.89 [95% CI, 1.23-2.88]; P=0.003) after adjustment for confounders in patients with acute ischemic stroke and atrial fibrillation taking OACs. Patients with exactly 1 CMB had a similar rate of MACCE compared with those without CMBs (P=0.461). However, patients with multiple CMBs (≥2), particularly high burden CMBs (≥5), had a significantly higher proportion of MACCE. Both CMB-positive groups with lobar and deep CMB had more frequent MACCE than the CMB-negative group, and the rate of MACCE was not different according to CMB location. In patients treated with warfarin, CMB was significantly associated with a risk of MACCE (P=0.002), but not in patients treated with direct OACs (P=0.517). CONCLUSIONS: The study results indicate that the risk of future MACCE increased with increasing CMB burden in patients with AIS and atrial fibrillation taking OACs, while the anatomic location of CMBs did not influence the risk of future MACCE. This risk seemed to be more apparent in patients taking warfarin.

Sleep Duration and Stroke: Prospective Cohort Study and Mendelian Randomization Analysis.

BACKGROUND AND PURPOSE: Studies of sleep duration in relation to specific types of stroke are scarce. Moreover, the results are inconclusive and causality remains unclear. Our objective was to investigate whether sleep duration is associated with risk of stroke and its types using observational and Mendelian randomization designs. METHODS: The prospective study included 79 881 women and men (45-79 years of age) who were followed up for incident stroke or death over a mean follow-up of 14.6 years (1 164 646 person-years) through linkage to Swedish Registers. For the Mendelian randomization study, single-nucleotide polymorphisms associated with sleep duration were identified from a genome-wide association study. Summarized data for genetic associations with stroke were obtained from publicly available data of the MEGASTROKE and the International Stroke Genetics Consortia. RESULTS: Compared with normal sleep duration, long sleep (≥9 hours per day) was associated with increased risk of total and ischemic stroke (hazard ratios [95% CI], 1.12 [1.03-1.22] and 1.14 [1.03-1.24], respectively), whereas short sleep (<7 h/d) was linked to higher risk of intracerebral hemorrhage (hazard ratio [95% CI], 1.21 [1.03-1.41]). The 2-sample Mendelian randomization analysis supported no causal association of short or long sleep duration with ischemic stroke as a whole. CONCLUSIONS: In a prospective study, long sleep duration was associated with increased risk of total and ischemic stroke, whereas short sleep was linked to increased risk of intracerebral hemorrhage. However, the Mendelian randomization analysis did not show a significant detrimental effect of short or long sleep duration on the risk of total stroke or stroke types.

Anticoagulation and Risk of Stroke Recurrence in Patients with Embolic Stroke of Undetermined Source Having No Potential Source of Embolism.

BACKGROUND: This study aimed to determine whether use of oral anticoagulants (OACs) was associated with a reduced risk of recurrent stroke compared with use of antiplatelets (APs) in patients with embolic stroke of undetermined source (ESUS) having no potential source of embolism. METHODS: Of 8,790 patients with acute ischemic stroke registered at 7 centers in the Fukuoka Stroke Registry from June 2007 to May 2017, we included 681 patients (mean age 69.7 [SD 14.1] years, 48.3% men) who experienced ESUS without a potential source of embolism and received OAC alone or AP alone. We estimated hazard ratios (HRs) and 95% confidential intervals (CIs) of recurrent ischemic stroke or any stroke after discharge using a Cox proportional hazards model and Fine and Gray model. RESULTS: During a mean follow-up of 3.4 (SD 1.7) years, event rates of recurrent ischemic stroke were 4.4 per 100 person-years in 489 patients treated with AP and 2.0 per 100 person-years in 192 patients treated with OAC. OAC use was associated with a reduced risk of recurrent ischemic stroke, even after adjusting for potential confounding factors (multivariable-adjusted HR [95% CI], 0.42 [0.23-0.80]) and when additionally considering death as a competing risk (0.45 [0.24-0.85]). The reduced risk of recurrent ischemic stroke was still observed in patients treated with OAC (0.32 [0.15-0.67]) in reference to propensity score-matched patients treated with AP. These associations were maintained for all types of stroke, including ischemic and hemorrhagic stroke. CONCLUSIONS: This nonrandomized observational study suggests that anticoagulation therapy might be associated with a reduced risk of recurrent stroke compared with antiplatelet therapy in patients with ESUS in whom no potential source of embolism was identified. Further study should be performed in consideration of a potential source of embolism even in patients with ESUS.

Embolic stroke of undetermined source: Focusing on atrial cardiopathy and patent foramen ovale.

BACKGROUND: Atrial cardiopathy(AC) and patent foramen ovale (PFO) are two etiologies of embolic strokes of undetermined source (ESUS). We aimed to explore the relationship between them in ESUS. METHODS: A total of 1146 participants were included from January 2019 to June 2022, which included the ESUS group and non-embolic stroke which includes LAA(large arterial atherosclerosis) + SAO(small artery occlusion) group. AC was defined as the presence of at least one of the following: PTFV1(P-wave terminal force in lead V1) > 4000 µV*ms in the electrocardiograms, NT-proBNP(N-terminal probrain natriuretic peptide) > 250 pg/mL in laboratory tests or LAD(left atrial diameter) > 3.8 cm for women and > 4.0 cm for men in cardiac ultrasound. The presence of PFO was assessed by transthoracic echocardiography, transcranial Doppler ultrasound, transesophageal echocardiography or cardiac MRI. PFO was considered pathogenic if the RoPE score was 7 to 10. RESULTS: The prevalence of AC and PFO was higher in the ESUS group than the LAA + SAO group. The prevalence of AC was lower in ESUS patients with pathogenic PFO (37.9%) than those without PFO (68.4%) and with incidental PFO (64.0%) (p = 0.006). The prevalence of pathogenic PFO was lower in ESUS patients with AC than those without AC (6.0% vs. 17.8%, p = 0.006). The AUC(area under the curve) of PTFV1 for predicting ESUS was 0.724 [95%CI (0.686-0.762), p < 0.05)], indicating that PTFV1 the most valuable AC biomarker. CONCLUSIONS: The prevalence of AC is inversely related to the prevalence of pathogenic PFO in ESUS patients. PTFV1 was the most valuable index to predict ESUS among the AC biomarkers.

Silent brain infarctions in patients with acute cardioembolic stroke.

INTRODUCTION AND AIM: The advances and the wide use of brain imaging have considerably increased the prevalence of silent brain infarctions (SBI). We aim in this study to determine the prevalence of SBI in patients presenting with acute cardioembolic stroke and the predictive cardiovascular risk factors. METHODS: This retrospective study included 267 patients presenting with acute cardioembolic stroke in the emergency and/or neurology departments of the Hassan II University Hospital Center. Clinical, biological and echocardiographic characteristics were recorded. All patients were screened for SBI by brain imaging. RESULTS: The prevalence of SBI in our series was 46%. A group of 203 non-valvular patients and a group of 64 valvular patients were distinguished. In non-valvular group, the average age was 72.97±10.53years. The prevalence of SBI was 45.3%. Forty-four percent of patients with SBI had atrial fibrillation (AF). In multivariate regression analysis, the history of previous stroke, CHA2DS2-VASc Score≥4, enlarged left atrium (LA), the association of AF with enlarged LA and the lability of International Normalized Ratio in patients initially treated with anticoagulants were significantly associated with the occurrence of SBI (P=0.013, P=0.032, P=0.0001, P=0.01, P=0.03, respectively). Territorial location was significantly the most frequent (P=0.007). In valvular group, the average age was 57.19±14.38years. The prevalence of SBI was 48.4%. In multivariate regression analysis, SBI were significantly associated with moderate or severe mitral stenosis (P=0.02) and with the enlarged LA (P=0.02). In all patients, Modified Rankin Scale at 3 months of discharge from the acute stroke was significantly higher (mRS≥3) in patients with SBI (P=0.04). CONCLUSIONS: SBI requires good management of associated cardiovascular risk factors in a population presenting with initial cardioembolic stroke.

Mechanisms of Hypercoagulability Driving Stroke Risk in Obesity: A Mendelian Randomization Study.

BACKGROUND AND OBJECTIVES: Obesity is hypothesized to induce a hypercoagulable state that increases stroke risk. The molecular mechanisms underlying this association are largely uncharacterized. We aimed to apply mendelian randomization to identify whether the association of genetically proxied body mass index (BMI) with cardioembolic stroke risk is mediated by changes in levels of circulating coagulation factors. METHODS: Genetic proxies for BMI and levels of circulating coagulation factors were obtained, respectively, from the Genetic Investigation of ANthropometric Traits consortium (n = 694,649) and deCODE cohort (n = 35,559). Genetic associations with cardioembolic stroke risk were obtained from the GIGASTROKE consortium (10,804 cases and 1,234,804 controls). We performed a two-sample mendelian randomization analysis testing the association of genetically proxied BMI with cardioembolic stroke risk, genetically proxied BMI with levels of coagulation factors, and genetically proxied levels of coagulation factors with cardioembolic stroke risk. These estimates were carried forward to mediation and sensitivity analyses. RESULTS: A 1-SD increase in genetically proxied BMI associated with increased cardioembolic stroke risk (OR of cardioembolic stroke per 1-SD of BMI 1.20, 95% CI 1.08-1.33, p = 8.65 × 10-4) with similar findings in statistical sensitivity analyses more robust to the inclusion of pleiotropic variants. Genetically proxied BMI was further associated with increased levels of Factor VII, Factor Xa, Factor XI, and Protein S (all p < 5.9 × 10-6). Of these factors, genetically proxied levels of Factor XI were associated with cardioembolic stroke risk (OR of cardioembolic stroke per 1-SD increase in Factor XI levels 1.32, 1.19-1.46, p = 6.18 × 10-8). The mediated effect of genetically proxied BMI through Factor XI accounted for 26% (6%-49%) of the total effect of BMI on cardioembolic stroke. DISCUSSION: Human genetic data support increased levels of Factor XI as a mechanistic explanation for how obesity increases cardioembolic stroke risk. The clinical relevance of this association warrants further investigation within ongoing clinical trials of Factor XI inhibition.