Repeated Cardioembolic Stroke after COVID-19 mRNA Vaccination: A Case Report.

OBJECTIVE: There have been no reports suggesting a relationship between the COVID-19 mRNA vaccines that encodes the spike glycoprotein of SARS-CoV-2 and cerebrovascular disease. A case of repeated cardioembolic stroke after vaccination with the BNT162b2 (Pfizer) COVID-19 mRNA vaccine is presented. METHODS: Imaging and laboratory findings, treatment decisions, and the outcome of this case are presented. RESULTS: An 83-year-old Japanese woman developed right hemiplegia and motor aphasia three days after receiving her first dose of the BNT162b2 (Pfizer) COVID-19 mRNA vaccine. She had been taking rivaroxaban for persistent atrial fibrillation for 10 years, but had no symptomatic ischemic strokes. On magnetic resonance imaging (MRI) the left middle cerebral artery (MCA) was occluded. Intravenous recombinant tissue-plasminogen activator (rt-PA) therapy and mechanical thrombectomy were performed, and she recovered almost fully. However, three days after the second dose, she developed left hemiplegia and left hemispatial neglect. MRI showed occlusion of the right MCA. Only mechanical thrombectomy was performed again, but it could not be resumed due to the hard thrombus. DISCUSSION: In this case, it is difficult to exclude a causal relationship between the COVID-19 mRNA vaccine and ischemic stroke. This association needs to be carefully monitored.

Ischemic Stroke.

This concise review of the epidemiology, pathophysiology, evaluation, acute management, and prevention of ischemic stroke targets internists, family practitioners, and emergency physicians who manage patient with stroke.

Artificial Inteligence-Based Decision for the Prediction of Cardioembolism in Patients with Chagas Disease and Ischemic Stroke.

BACKGROUND: Chagas disease (CD) and ischemic stroke (IS) have a close, but poorly understood, association. There is paucity of evidence on the ideal secondary prophylaxis and etiological determination, with few cardioembolic patients being identified. AIMS: This study aimed to describe a multicenter cohort of patients with concomitant CD and IS admitted in tertiary centers and to create a predictive model for cardioembolic embolism in CD and IS. MATERIALS AND METHODS: We retrospectively studied data obtained from electronic medical and regular medical records of patients with CD and IS in several academic, hospital-based, and university hospitals across Brazil. Descriptive analyses of cardioembolic and non-cardioembolic patients were performed. A prediction model for cardioembolism was proposed with 70% of the sample as the derivation sample, and the model was validated in 30% of the sample. RESULTS: A total of 499 patients were analyzed. The median age was similar in both groups; however, patients with cardioembolic embolism were younger and tended to have higher alcoholism, smoking, and death rates. The predictive model for the etiological classification showed close relation with the number of abnormalities detected on echocardiography and electrocardiography as well as with vascular risk factors. CONCLUSIONS: Our results replicate in part those previously published, with a higher prevalence of vascular risk factors and lower median age in patients with cardioembolic etiology. Our new model for predicting cardioembolic etiology can help identify patients with higher recurrence rate and therefore allow an optimized strategy for secondary prophylaxis.

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.

Endovascular Therapy for Acute Ischemic Stroke in Patients with Large-Vessel Occlusion due to Atherosclerotic Stenosis.

OBJECTIVES: Endovascular therapy (EVT) is safe and effective for acute ischemic stroke (AIS) due to large-vessel occlusion (LVO). However, the influence of the AIS subtype (large-artery atherosclerosis [LAA] or cardioembolism [CE]) on clinical outcome in patients treated with EVT remains unclear. This study aimed to evaluate the differences in clinical results between the two subtypes using data from a multicenter prospective registry (RESCUE-Japan Registry 2). MATERIALS AND METHODS: Among 2420 patients in RESCUE-Japan Registry, 682 patients who were diagnosed with LAA or CE were enrolled. The primary outcome was a modified Rankin Scale (mRS) score of 0-2 at 90 days. The secondary outcomes were 90-day mRS 0-1, 0-3, and 6. The relationship between time from onset and clinical outcome was also analyzed. RESULTS: Among the 682 patients, 124 were classified into the LAA group and 558 into the CE group. The baseline National Institutes of Health Stroke Scale score was significantly lower (median 15 vs. 18, p < 0.001). At 90 days, mRS 0-2 was observed in 54 of 124 patients (44%) in the LAA group and 232 of 558 patients (42%) in the CE group (p = 0.69). The proportion of patients with mRS 0-2 tended to decrease according to onset-to-puncture time in the CE group but not in the LAA group (ptrend=0.0007). CONCLUSIONS: The rate of good outcome was similar between LVO due to LAA and CE. However, the rate of favorable outcome did not decrease according to onset-to-puncture time in the LAA group.

Analyzing Cost-Effectiveness of Allocating Neurointerventionist for Drive and Retrieve System for Patients with Acute Ischemic Stroke.

OBJECTIVES: There are regional disparities in implementation rates of endovascular thrombectomy due to time and resource constraints such as endovascular thrombectomy specialists. In Hokkaido, Japan, Drive and Retrieve System (DRS), where endovascular thrombectomy specialists perform early endovascular thrombectomies by traveling from the facilities where they normally work to facilities closer to the patient. This study analyzed the cost-effectiveness of allocating a endovascular thrombectomy specialist for DRS to treat stroke patients. MATERIALS AND METHODS: he number of ischemic stroke patients expected to receive endovascular thrombectomy in Hokkaido in 2015 was estimated. It was assumed that an additional neutointerventionist was allocated for DRS. The analysis was performed from the government's perspective, which includes medical and nursing-care costs, and the personnel cost for endovascular thrombectomy specialist. The analysis was conducted comparing the current scenario, where patients received endovascular thrombectomy in facilities where endovascular thrombectomy specialists normally work, with the scenario with DRS within 60 min drive distance. Patient transport time was analyzed using geographic information system, and patient severity was estimated from the transport time. The primary outcome was incremental cost-effectiveness ratio (ICER) in each medical area which was calculated from the incremental costs and the incremental quality-adjusted life years (QALYs), estimated from patient severity using published literature. The entire process was repeated 100 times. RESULTS: DRS was most cost-effective in Kamikawachubu area, where the ICER was $14,173±16,802/QALY, significantly lower than the threshold that the Japanese guideline suggested. CONCLUSIONS: Since DRS was cost-effective in Kamikawachubu area, the area should be prioritized when a endovascular thrombectomy specialist for DRS is allocated as a policy.

ASPECTS-Region-Dependent Functional Outcomes after Endovascular Therapy in Patients with Cardioembolic Stroke.

OBJECTIVES: Cardioembolic stroke has a poor prognosis. We evaluated the region-dependent efficacy of endovascular therapy (EVT) based on diffusion-weighted imaging-Alberta Stroke Program Early CT Score (DWI-ASPECTS). METHODS: This post-hoc analysis of the RELAXED study, which investigated the optimal timing of rivaroxaban to prevent nonvalvular atrial fibrillation (NVAF) recurrence in patients with acute ischemic stroke (AIS), included NVAF patients admitted with AIS or transient ischemic attack in the middle cerebral artery (MCA), with internal carotid artery (ICA), M1, or M2-MCA occlusion. Relationships between DWI-ASPECTS region and functional outcome (modified Rankin Scale [mRS]), mortality, recurrence, and hemorrhagic stroke were compared between patients with and without EVT, and adjusted odds ratios for age, pre-stroke mRS, National Institutes of Health Stroke Scale (NIHSS), ICA occlusion, infarct size, recombinant tissue plasminogen activator (rt-PA) use, and onset-to-hospitalization time were estimated. RESULTS: EVT patients had significantly lower hemoglobin levels, higher median NIHSS scores, more lentiform nucleus infarcts, ICA or M1-MCA occlusions, treatment with rt-PA, and fewer M3, M5, or M6 infarcts and M2-MCA occlusions than no-EVT patients. EVT patients had shorter onset-to-hospitalization times and more frequent favorable functional outcomes (p=0.007). Mortality, recurrent ischemic stroke, and hemorrhagic infarction were similar in both groups. EVT was associated with significantly better functional outcomes among patients with insular ribbon (p=0.043) and M3 (p=0.0008) infarcts. M3 patients had significantly fewer rt-PA and EVT, and longer onset-to-hospitalization times. CONCLUSIONS: An occlusion in the insular ribbon or M3 region was associated with favorable functional outcomes in patients treated with EVT after cardioembolic stroke.

Endovascular Treatment of Infective Endocarditis-Related Acute Large Vessel Occlusion Stroke.

OBJECTIVES: Embolic stroke is a frequent complication of infective endocarditis yet lacks acute treatment as intravenous thrombolysis should be avoided due to high risk of intracerebral hemorrhage. Mechanical thrombectomy for large vessel occlusion may be a promising treatment but there is limited data on safety outcomes in infective endocarditis. MATERIALS AND METHODS: In this multi-center retrospective case series, we reviewed data from patients with infective endocarditis-related large vessel occlusion who underwent mechanical thrombectomy in 9 US hospitals. RESULTS: We identified 15 patients at 9 hospitals. A minority presented with signs suggesting infection (2 patients (14%) had fever, 7 (47%) were tachycardic, 2 (13%) were hypotensive, and 8 (53%) had leukocytosis). The median National Institute of Health Stroke Score decreased from 19 (range 9-25) at presentation to 7 post-thrombectomy (range 0-22, median best score post-thrombectomy), and the median modified Rankin Scale on or after discharge for survivors was 3 (range 0-6). Approximately 57% of patients had a modified Rankin Scale between 0 and 3 on or after discharge. Hemorrhagic transformation was observed in 7/15 (47%). The mechanical thrombectomy group had 2/9 petechial hemorrhagic transformation (22%), compared to 4/6 parenchymal hematomas (67%) in the tissue plasminogen activator + mechanical thrombectomy group. CONCLUSIONS: Our findings suggest that patients with large vessel occlusion due to infective endocarditis may not present with overt signs of infection. Mechanical thrombectomy may be an effective treatment in this patient population for whom intravenous thrombolysis should be avoided.

Cancer and Embolic Stroke of Undetermined Source.

One-quarter to one-third of ischemic strokes have no established mechanism after standard diagnostic evaluation and are classified as embolic stroke of undetermined source (ESUS). Failure of randomized trials to demonstrate a benefit of direct oral anticoagulants over aspirin for the treatment of ESUS as a single homogeneous entity has led to renewed interest by stroke experts to divide ESUS into subgroups. Emerging data suggest that active cancer, which is present in 5% to 10% of patients with ESUS, is a distinct and important subgroup of ESUS with unique clinical characteristics, underlying pathophysiologies, and treatment and prognostic considerations. Furthermore, the prevalence of cancer-related ESUS is expected to increase as patients with cancer, even those with distant metastases, survive longer due to improvements in cancer treatments. In this topical review, we examine the epidemiological link between ESUS and cancer, the clinical features and potential mechanistic underpinnings of ESUS with cancer (with a focus on novel biomarkers and their relationship to recurrent stroke and other thromboembolic events), and the potential treatment strategies for cancer-related ESUS. We include a critical appraisal of existing data and ongoing or planned clinical trials of different antithrombotic approaches. As cancer-related ESUS is a dynamic disease with variable course, we recommend close collaboration between neurologists and oncologists to develop individualized management plans.

4-Hydroxyl-2-Nonenal Localized Expression Pattern in Retrieved Clots is Associated with Large Artery Atherosclerosis in Stroke Patients.

OBJECTIVES: The relationship between stroke etiology and clot pathology remains controversial. MATERIALS AND METHODS: We performed histological analysis of clots retrieved from 52 acute ischemic stroke patients using hematoxylin and eosin staining and immunohistochemistry (CD42b and oxidative/hypoxic stress markers). The correlations between clot composition and the stroke etiological group (i.e., cardioembolic, cryptogenic, or large artery atherosclerosis) were assessed. RESULTS: Of the 52 clots analyzed, there were no significant differences in histopathologic composition (e.g., white blood cells, red blood cells, fibrin, and platelets) between the 3 etiological groups (P = .92). By contrast, all large artery atherosclerosis clots showed a localized pattern with the oxidative stress marker 4-hydroxyl-2-nonenal (P < .01). From all 52 clots, 4-hydroxyl-2-nonenal expression patterns were localized in 28.8% of clots, diffuse in 57.7% of clots, and no signal in 13.5% of clots. CONCLUSIONS: A localized pattern of 4-hydroxyl-2-nonenal staining may be a novel and effective marker for large artery atherosclerosis (sensitivity 100%, specificity 82%).

Inconsistent centralised versus non-centralised ischaemic stroke aetiology.

BACKGROUND AND PURPOSE: The Trial of Org 10 172 in Acute Stroke Treatment (TOAST) system is the most widely used aetiological categorisation system in clinical practice and research. Limited studies have validated the accuracy of routine aetiological diagnosis of patients with ischaemic stroke according to the TOAST criteria when the reported subtype is assumed to be correct. We investigated the agreement between centralised and non-centralised (site-reported, at discharge) stroke subtypes in the Third China National Stroke Registry (CNSR-III), and analysed the influence of classification consistency on evaluation during hospitalisation and for secondary prevention strategy. METHODS: All patients with ischaemic stroke from the CNSR-III study with complete diffusion-weighted imaging data were included. We used multivariable Cox proportional-hazard regression models to evaluate the factors associated with consistency between centralised and non-centralised stroke subtypes. Sensitivity analyses were conducted of the subgroup of patients with complete information. RESULTS: This study included 12 180 patients (mean age, 62.3 years; and women, 31.4%). Agreement between centralised and non-centralised subtype was the highest for the large-artery atherosclerosis subtype stroke (77.4% of centralised patients), followed by the small-vessel occlusion subtype (40.6% of centralised patients). Agreements for cardioembolism and stroke of other determined aetiology subtypes were 38.7% and 12.2%, respectively. Patient-level and hospital-level factors were associated with the inconsistency between centralised/non-centralised aetiological subtyping. This inconsistency was related to differences in secondary prevention strategies. Only 15.3% of the newly diagnosed patients with cardioembolism underwent centralised subtyping with indications to receive oral anticoagulants at discharge. In comparison, 51.3% of the consistent cardioembolism group and 42.0% of the centrally reassigned cardioembolism group with anticoagulation indications were prescribed oral anticoagulants. CONCLUSIONS: Substantial inconsistency exists between centralised and non-centralised subtyping in China. Inaccurate aetiological subtyping could lead to inadequate secondary prevention, especially in patients with cardioembolic stroke.

Quantitative Morphology of Cerebral Thrombi Related to Intravital Contraction and Clinical Features of Ischemic Stroke.

BACKGROUND AND PURPOSE: The purpose was to assess quantitatively and qualitatively the composition and structure of cerebral thrombi and correlate them with the signs of intravital clot contraction (retraction), as well as with etiology, severity, duration, and outcomes of acute ischemic stroke. METHODS: We quantified high-resolution scanning electron micrographs of 41 cerebral thrombi for their detailed cellular and noncellular composition and analyzed histological images for the overall structure with the emphasis on red blood cell compression, fibrin age, and the signs of inflammation. RESULTS: Cerebral thrombi were quite compact and had extremely low porosity. The prevailing cell type was polyhedral compressed erythrocytes (polyhedrocytes) in the core, and fibrin-platelet aggregates were concentrated at the periphery; both findings are indicative of intravital contraction of the thrombi. The content of polyhedrocytes directly correlated with the stroke severity. The prevalence of fibrin bundles was typical for more severe cases, while the content of fibrin sponge prevailed in cases with a more favorable course. The overall platelet content in cerebral thrombi was surprisingly small, while the higher content of platelet aggregates was a marker of stroke severity. Fibrillar types of fibrin prevailed in atherothrombogenic thrombi. Older fibrin prevailed in thrombi from the patients who received thrombolytics, and younger fibrin dominated in cardioembolic thrombi. Alternating layers of erythrocytes and fibrin mixed with platelets were common for thrombi from the patients with more favorable outcomes. Thrombi with a higher number of leukocytes were associated with fatal cases. CONCLUSIONS: Most cerebral thrombi undergo intravital clot contraction (retraction) that may be of underestimated clinical importance. Despite the high variability of the composition and structure of cerebral thrombi, the content of certain types of blood cells and fibrin structures combined with the morphological signs of intravital contraction correlate with the clinical course and outcomes of acute ischemic stroke.

Neuroinflammatory Mechanisms in Ischemic Stroke: Focus on Cardioembolic Stroke, Background, and Therapeutic Approaches.

One of the most important causes of neurological morbidity and mortality in the world is ischemic stroke. It can be a result of multiple events such as embolism with a cardiac origin, occlusion of small vessels in the brain, and atherosclerosis affecting the cerebral circulation. Increasing evidence shows the intricate function played by the immune system in the pathophysiological variations that take place after cerebral ischemic injury. Following the ischemic cerebral harm, we can observe consequent neuroinflammation that causes additional damage provoking the death of the cells; on the other hand, it also plays a beneficial role in stimulating remedial action. Immune mediators are the origin of signals with a proinflammatory position that can boost the cells in the brain and promote the penetration of numerous inflammatory cytotypes (various subtypes of T cells, monocytes/macrophages, neutrophils, and different inflammatory cells) within the area affected by ischemia; this process is responsible for further ischemic damage of the brain. This inflammatory process seems to involve both the cerebral tissue and the whole organism in cardioembolic stroke, the stroke subtype that is associated with more severe brain damage and a consequent worse outcome (more disability, higher mortality). In this review, the authors want to present an overview of the present learning of the mechanisms of inflammation that takes place in the cerebral tissue and the role of the immune system involved in ischemic stroke, focusing on cardioembolic stroke and its potential treatment strategies.

Mechanical circulatory support for cardiovascular complications in a young COVID-19 patient.

BACKGROUND: The current coronavirus (COVID-19) pandemic is associated with severe pulmonary and cardiovascular complications. CASE PRESENTATION: This report describes a young patient with COVID-19 without any comorbidity presenting with severe cardiovascular complications, manifesting with pulmonary embolism, embolic stroke, and right heart failure. CONCLUSION: Management with short-term mechanical circulatory support, including different cannulation strategies, resulted in a successful outcome despite his critical cardiovascular status.

The role of echocardiography in the embolic stroke of undetermined source.

: Echocardiography plays an important role both in the diagnosis and the treatment/prevention of embolic stroke of undetermined source and should be performed as soon as possible for preventing ischemic stroke recurrencies, which occur more frequently during the first week after the first ischemic event. Early identification of the cause of a transient ischemic attack or stroke is indeed a primary goal for the neurologist in the Stroke Unit and requires specific diagnostic strategies. Echocardiography, together with other diagnostic tools such as carotid and transcranial ultrasounds, provides this information promptly. In particular, echocardiography might be able to detect the main sources of the embolic stroke, such as atrial fibrillation, ventricular akinesia, aortic atheroma plaques and/or cardiac shunts. The present review discusses the importance and the practical role of echocardiography as a crucial diagnostic tool for detecting the main source of emboli in the setting of the acute stroke.