bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract Number ‐ 227: Retrograde embolism from a Subclavian Thrombus causing Acute Ischemic Stroke in the Middle Cerebral Artery
Authors: Philip Karan , Blanden Adam , Kleinhenz Elena , Masoud Hesham 
Published: April 2023

Introduction
Intracranial embolism to the middle cerebral artery usually occurs because of embolization from the heart, carotid artery or the aorta. Here we describe a case of a subclavian thrombus, embolizing to the middle cerebral artery. Retrograde embolism is a rarely described mechanism of acute ischemic stroke.

Methods
A 49‐year‐old gentleman with a history of hyperlipidemia, peripheral artery disease, smoking, prior stroke, previously treated arteriovenous malformation (AVM) in the left parieto‐occipital region and active methamphetamine use presented with sudden onset dysarthria and left facial weakness (NIH stroke scale–3). CT angiogram (CTA) head and neck demonstrated a right M2 inferior division occlusion and noted nonocclusive thrombus attached to right subclavian artery atherosclerotic plaque, proximal to the origin of the right vertebral artery and otherwise minimal extracranial, and intracranial atherosclerotic disease. He was not a candidate for IV thrombolysis due to his AVM, or mechanical thrombectomy (MT) due to low NIHSS. Apixaban was started. Trans‐esophageal echocardiogram (TEE) demonstrated a grade 2 PFO. Venous doppler ultrasound performed of his upper and lower extremities was negative. On day 2 of hospitalization, his left hemiparesis and dysarthria worsened. Repeat CTA head and neck showed absence of the right subclavian thrombus and new distal M1‐MCA thrombus, suggestive of retrograde embolism from the right subclavian artery. The patient was started on IV heparin and aspirin. A stroke in young work‐up was sent including antinuclear antibodies (ANA), antineutrophil cytoplasmic antibodies (ANCA), homocysteine, hexagonal phase phospho proteins, antiphospholipid antibodies, HIV, rheumatoid factor, cryoglobulin, hepatitis B antibodies, hepatitis C antibodies, sickle cell screen, Sjogren’s syndrome antibodies, drug screen, and was negative.

Results
Embolism (cardioembolism and artery–artery embolism) to the intracranial vasculature is an important cause of acute ischemic stroke. Retrograde embolization is rarely described as a cause of ischemic stroke. Our patient presented initially with distal right M2 occlusion and subocclusive thrombus of the right subclavian artery, associated with focal atherosclerosis but otherwise patent extracranial and intracranial cerebral vessels. Work‐up including transesophageal echocardiogram, and hypercoagulable work‐up was unrevealing. Repeat CT angiogram obtained in view of worsening deficits revealed absence of his right subclavian thrombus and new distal M1‐MCA occlusion presumed retrograde embolism from the right subclavian artery. This is may represent the consequence of local turbulence and retrograde flow during diastole.

Conclusions
When considering sources of embolic stroke, retrograde embolism should be considered in patients with focal atherosclerosis.
Abstract Number ‐ 231: Role of Anticoagulation in Recurrent Basilar Artery Thrombosis Secondary to Dolichoectasia, a Case Report
Authors: Mannem Narmada , Yelverton Nicholas B 
Published: April 2023

Introduction
Basilar artery thrombosis accounts for a small part of ischemic strokes but contributes to one‐fifth of the posterior circulation strokes. Recurrent basilar artery thrombosis secondary to dolichoectasia is caused by abnormal flow in the dilated artery and can result in cerebral ischemia. We present a similar case of recurrent thrombosis with a missed dose of anticoagulation and dehydration on two separate occasions.

Methods
An 81‐year‐old man with a past medical history of ulcerative colitis with colostomy, provoked deep venous thrombosis presented as a transfer from an outside hospital with acute onset of dysarthria, nausea/vomiting, unsteadiness, and left hemiparesis. CT angiogram of head and neck revealed right vertebral thrombosis extending into the basilar artery with dolichoectasia involving distal right vertebral artery and basilar artery. He was started on heparin infusion with improvement in symptoms and a return to baseline. He was later transitioned to apixaban and discharged home. On a follow‐up office visit two months later, his repeat CT angiogram revealed resolution of the thrombus. He was advised to continue the medication due to the risk of recurrent occlusion secondary to vessel anomaly. After four months, the patient returned to the emergency department with acute onset dizziness, imbalance, nausea, and vomiting. CT angiogram of the head and neck was performed which revealed non‐occlusive thrombosis in the basilar artery. On evaluation by neurology, he admits to three missed doses of apixaban. Clinical and laboratory data were concerning for volume depletion. On further questioning about his symptoms, he mentions decreased oral intake on the day of colostomy change. He was advised to continue apixaban and stay hydrated.

Results
After fifteen months of the first presentation, the patient is symptom‐free but was continued on anticoagulation with apixaban to prevent recurrent events.

Conclusions
The role of short‐term and long‐term anticoagulation in basilar artery occlusion is less studied. No prospective trials were done so far to suggest that antithrombotic therapy lowers the risk of recurrent ischemic events and/or anticoagulation is superior to antiplatelets. Dolichoectasia by itself can increase the risk of recurrent thrombosis and dehydration likely facilitated the thrombosis in our patient during the event of missed anticoagulation.
Abstract Number ‐ 233: Vaccine‐Induced Thrombotic Thrombocytopenia presenting as Massive Stroke: Case Report and Literature Review
Authors: Ghani Mohammad R , Shi Ping , Brown Randall , Coghlan Meghan A , Hasan Saad , Ander Tracy M , Haboubi Michael , Liu Wei 
Published: April 2023

Introduction
Vaccines have been pivotal for the COVID‐19 pandemic. Rare adverse effects of the vaccines such as thrombosis have been observed. Here we report a case of an acute malignant ischemic stroke in a young healthy patient caused by thrombosis due to Vaccine‐Induced Thrombotic Thrombocytopenia (VITT).

Methods
Electronic chart review for a case report.

Results
A 43‐year‐old Caucasian female with a medical history of hypertension was found unresponsive on the morning of presentation. Her Last known normal was the night before. On arrival in the emergency department, she was globally aphasic, with left eye deviation, right‐sided neglect, right facial droop, and right‐side hemiplegia. Pupils were equal and reactive to light. NIHSS was 23. Head CT showed large left middle cerebral artery and anterior cerebral artery strokes with significant cerebral edema and midline shift. Head and neck CTA showed left ICA and left MCA occlusions. She was taken for decompressive craniectomy immediately. Ten days prior to the stroke, she received her first COVID vaccination. She smoked but did not take oral contraceptives. She did not have a family history of hypercoagulability. Stroke workup showed LDL 141, A1C 4.8%, and a negative COVID test. She had normal white and red blood cell counts but low platelet counts at 73,000, which was 233,000 one month prior. 2D echocardiogram showed an ejection fraction of 54% and no patent foramen ovale or thrombus. Lower extremity doppler showed deep vein thrombosis. Because of arterial and venous thrombosis with new thrombocytopenia, hematology was consulted. She was found to have positive anti–PF4–heparin antibody, leading to a VITT diagnosis. She received IVIG, rituximab, and steroid treatments, and her platelets gradually returned to the baseline. She was later transferred to a rehabilitation facility.

Conclusions
VITT is characterized by thrombosis and thrombocytopenia with positive PF4 antibodies after a median of 14 days post‐vaccination. It was reported in COVID vaccines from all manufacturers. The mechanism remains unclear. The current hypothesis describes a two‐hit process through which the vaccine triggers neoantigen formation (the first hit) followed by a systemic inflammatory response (the second hit). Incidence of VITT from COVID vaccinations is unknown but the reported cases were rare. VITT‐caused acute stroke, especially malignant strokes, is even rarer.Although the COVID vaccines can cause rare life‐threatening adverse events, they are essential for controlling the pandemic. When encountering an ischemic stroke patient with thrombocytopenia, we should consider VITT. Further study with post‐vaccination registration and monitoring is warranted.
Abstract Number ‐ 235: Stroke Management in Left Ventricular Non‐Compaction Syndrome (LVNC): Report of 2 Cases
Authors: Tamrazian Eric , Witter Danica , Zeitjian Armen , Mehta Bijal 
Published: April 2023

Introduction
Left Ventricular Non‐Compaction syndrome is a rare congenital cardiomyopathy that results in prominent endomyocardial trabeculations which increases the risk of left ventricular dysfunction, malignant arrhythmias and thromboembolic events. Its diagnosis is based on morphological changes seen on trans‐thoracic echocardiograph (TTE), which can often be missed as it is user dependent. Objective: To discuss two cases of stroke associated with LVNC at our institution as well as offer further diagnostic and therapeutic recommendations.

Methods
Case Report

Results
Case1: A 29‐year‐old gentleman with a history dilated cardiomyopathy of unclear etiology and prior stroke presented to our institution complaining of dizziness and right sided headache. He was found to have a right M2 occlusion resulting in an insular infarct. Patient was out of the window for any chemical or mechanical thrombectomy. Initial TTE showed a depressed ejection fraction of 45‐50‐% with a 6mm LV apical thrombus. Patient was started on anticoagulation with coumadin and follow up TTE 3 months later showed the same EF, but with resolution of the apical thrombus. Given the unclear etiology of his heart failure, he was sent for cardiac MRI which demonstrated deep endomyocardial trabeculae consistent with Left Ventricular Non‐Compaction Syndrome. Given new findings, patient was recommended to continue anticoagulation with coumadin indefinitely. Case 2: A 12‐year old boy with a history of Cerebral Palsy and cardiomyopathy due to a formal diagnosis of Left Ventricular Non‐Compaction syndrome shortly after birth presented with sudden right sided weakness. Patient was admitted to the PICU team for elevated level of care. He underwent an MRI of the brain and found to have a left MCA ischemic stroke. He was out of the window for any mechanical or chemical thrombectomy. He was started on anticoagulation after 4 days with a stable CT scan of the stroke.

Conclusions
In the first case, several TTE’s in the outpatient setting and two done while the patient was hospitalized did not identify the pathogenic trabeculae. The diagnosis was only made after a cardiac MRI was done, posing a delay in diagnosis and possible treatment that could have prevented thrombogenic environment in the patient’s LV leading to an acute stroke. In the second case, the patient did have a diagnosis of LVNC, but anticoagulation was never started. Currently, there there exists no current accepted guidelines for diagnoses and management of LVNC. We recommend a cardiac MRI if there is a concern for stroke in a patient with cardiac myopathy of unclear etiology. Furthermore, professional opinion based on several meta‐analysis suggests that anticoagulation should be started when LVEF is less than 40% or presence of a prior stroke in patient with LVNC. Given the rarity of this syndrome and the challenge with its diagnosis, further studies are needed to better evaluate its timely diagnosis and proper management.
Abstract Number ‐ 262: Cognitive Decline in Patients with Symptomatic Intracranial Stenosis and Effect of Serum Lipid Profile
Authors: Fakih Rami 
Published: April 2023

Introduction
We determined the effect of baseline low density lipoprotein (LDL) and triglyceride (TG) concentrations on cognitive decline, in patients with symptomatic high grade intracranial stenosis.

Methods
We analyzed a cohort of stroke patients who had baseline and 4 months follow‐up Montreal Cognitive Assessment (MoCA) scores. MoCA score worsening after 4 months was the outcome of interest, defined as worsening of ≥ 2 points from baseline. Baseline LDL and TG concentrations (mg/dl) were assessed, and univariate and multivariate analysis using logistic regression were performed to identify predictors of worsening MoCA scores.

Results
A total of 349 patients were analyzed. 313 and 315 patients had baseline LDL and TG, respectively. 61 (17%) had a worsening of MoCA scores. The mean baseline LDL was 97.3 (39.1) in the worsening group, compared to 110.6 (44.8) in those with no worsening (p = 0.014). 23% of patients with LDL < 100 had worsening in MoCA score compared to 11% of patients with LDL ≥ 100 (p< 0.006). The mean baseline TG was 145.7 (102.2) in the worsening group, compared to 170.7 (135.4) (p = 0.053). On multivariate analysis, higher age (p = 0.014) and lower baseline LDL (p = 0.046) were predictors of worsening MoCA scores.

Conclusions
Patients who did not undergo any worsening MoCA scores had higher LDL and TG levels at baseline, and only older age and lower baseline LDL scores predicted worsening scores at 4 months. Presumably, the patients with high baseline lipid levels were treated more aggressively with dietary modifications and statins, which could have led to cognitive protective effect regardless of serum lipid profile.
Abstract Number ‐ 265: Reduced‐dose ticagrelor versus full‐dose ticagrelor in patients with stroke: A retrospective cohort study
Authors: Tarabichi Ammar , Morsi Rami Z. , Metman Okker , Desai Harsh , Kothari Sachin , Carrión‐Penagos Julián , Thind Sonam , Coleman Elisheva , Brorson James R. , Mendelson Scott , Mansour Ali , Prabhakaran Shyam , Kass‐Hout Tareq 
Published: April 2023

Introduction
There has been an increase in use of ticagrelor in patients with ischemic stroke, particularly in the setting of clopidogrel resistance. Our study aims to retrospectively determine if aspirin plus ticagrelor at a reduced dose is effective in reducing the risk of recurrent stroke and/or other thrombotic events, without increasing the risk of bleeding.

Methods
In a prospectively maintained database, we performed a retrospective analysis of consecutive patients with acute ischemic stroke in a large academic comprehensive stroke center between September 1, 2020 to July 1, 2022. We compared in‐hospital mortality, 90‐day mortality, favorable functional outcome, defined as a modified Rankin Scale (mRS) score of 0 to 2, at 90 days, symptomatic intracranial hemorrhage (sICH), and asymptomatic intracranial hemorrhage (ICH), between patients on reduced‐dose ticagrelor versus those on full‐dose ticagrelor, in unadjusted and adjusted logistic regression models.

Results
We included 567 patients in our study. The mean age of these patients was 67.0 ± 15.0 years. Females represented 59.5% of the patients, and the majority of the patients were Black (80.0%). Intracranial atherosclerotic disease was the presumed stroke etiology in 96 patients (17.0%). Out of 567 patients, 432 were on a combination of both ticagrelor and aspirin. A total of 62 patients were on a reduced dose of ticagrelor (45 mg or 60 mg twice daily). The remaining 505 patients were on 90 mg twice daily dosing. New or recurrent ischemic stroke was similar across both groups (10.2% vs. 12.0%, p = 0.08). Symptomatic ICH was also found to be similar across both groups (8.2% vs. 9.3%, p = 0.06). Mortality or favorable functional outcome at 90 days also did not differ between the two groups (25.3% vs. 24.7%, p = 0.007; 28.2% vs. 27.3%, p = 0.006).

Conclusions
A lower dose of ticagrelor (45 or 60 mg twice daily) appears to be a safe and effective regimen in reducing risk of ischemic strokes without increasing hemorrhagic complications when compared to full‐dose ticagrelor at 90 mg twice daily. Further randomized trials are necessary to inform this recommendation.
Abstract Number ‐ 273: Gender differences in comborbidities among acute ischemic stroke patients with heart failure and thrombolytic therapy.
Authors: Joffe Jonah , Chen Willian 
Published: April 2023

Introduction
Aim: The purpose of this study is to determine risk factors that contribute to a gender difference in Acute Ischemic Stroke (AIS) patients with a past medical history of heart failure(HF) excluded from recombinant tissue plasminogen activator (rtPA).

Methods
Methods: The data for this analysis was extracted from the stroke registry of a regional stroke center from January 2010 until June 2016 in Greenville, SC. Data was analyzed using the logistic regression to identify factors significantly associated with exclusion receiving rtPA therapy in the AIS‐HF patient population stratified by gender.

Results
Results:A total of 590 AIS patients with HF that presented with AIS were identified. Factorsassociated with exclusion from rtPA for males included past history of antidepressants (OR = 0.728, 95% CI, 0.264‐2.012, P < 0.541), previous history of coronary artery stenosis (OR = 0.269,95%, Cl, 0.077‐0.941, P < 0.040). Factors associated with exclusion for females included age over75(OR = 0.975, 95% CI, 0.949‐1.000, P < 0.054), and history of chronic renal failure (OR = 0.235,95% CI, 0.078‐0.708, P < 0.010).

Conclusions
Conclusion: Our study identified risk factors that can be managed to eliminate gender difference and improve the eligibly of AIS patients with a history of heart failure for thrombolytic therapy.
Abstract Number ‐ 276: Stroke Management and Outcomes in Low‐ and Lower‐Middle‐Income Countries: A Systematic Review of 29,626 Patients
Authors: Brown Nolan , Aguirre Alexander , Rodgers James , Reardon Taylor , Shlobin Nathan , Ballatori Alexander , Shahrestani Shane , Gendreau Julian 
Published: April 2023

Introduction
Strokes affects almost 13 million new people each year and while the outcomes of stroke have improved over the past several decades in high income countries, the same cannot be seen in low‐ and lower‐middle‐income countries. This is the first study to identify the availability of diagnostic tools along with the rates of stroke mortality and other post‐stroke complications in the low‐and lower‐middle‐income countries.

Methods
A systematic review was completed with a search of the MEDLINE, Embase, and Scopus databases with adherence to the PRISMA guidelines. Studies were included if they reported any outcomes of stroke in low‐ and lower‐middle‐income countries as designated by The World Bank classification.

Results
A total of 24 studies were included, of which seven originated from Ethiopia, three from Zambia, two from Tanzania, Zimbabwe, and Iran. A single study from each of Botswana, Nigeria, Senegal, Ghana, Kenya, Cameroon, Uganda, and Sierra Leone were included. Of these studies the time from symptom onset to diagnosis varied greatly (< 24 hours to 28 days). Out of 20 studies reporting, 95% stated they had access to CT/MRI. Stroke mortality rates differed greatly across included studies with in‐hospital mortality occurring between 5.0%‐35.4% and 30‐day mortality between 11.7%‐60.1%. Good clinical outcomes (mRS score 0–2) was reported by several studies and was found to have a range between 4.9%‐19.6% at 30 days.

Conclusions
A severe healthcare disparity in access to care is present in low‐ and lower‐middle‐income countries where there is delayed diagnosis of strokes leading to increased rates of poor clinical outcomes for these patients.
Abstract Number: LBA18 Tissue‐Based Perfusion Imaging in Acute Cerebral Small Vessel Disease Ischemic Stroke
Authors: Fourcand Farah , Sahito Sindhu , Bozkurt Subutay , Fourcand Farah , Vyas Shrinjay , Fleyzor Suanne , Gadallah Nancy , Panezai Spozhmy , Mehta Siddhart , Kirmani Jawad 
Published: April 2023

Introduction
There is growing evidence for the role of CT perfusion in tissue‐based treatment of acute ischemic stroke (AIS) secondary to large vessel occlusion (LVO). The utility of tissue‐based perfusion imaging in acute cerebral small vessel disease AIS may be low yield with current technology available. The purpose of this study was to evaluate the utility of CT perfusion in identifying small lenticulostriate hypoperfusion in cerebral small vessel disease strokes.

Methods
Get With The Guidelines database was used for retrospective chart review of patients presenting to our comprehensive stroke center with small vessel disease stroke defined as subcortical or brain stem lacunar infarction < 1.5 cm. Other stroke etiologies were excluded. A tissue‐based grading system was used to identify regions of hypoperfusion ordinally ranging from 0 to 5 (1‐thalamocapsular, 1‐basal ganglia, 2‐internal capsule, 1 caudate). Two board‐certified vascular neurologists independently evaluated CT perfusion maps, and Cohen’s K was used to determine kappa inter‐rater agreement. Lesions were later confirmed with MR diffusion‐weighted imaging. Social science statistics software was used for data analysis.

Results
From April 2017 to July 2022, out of 563 patients with small vessel disease stroke, 77 patients had CT perfusion. Thirty‐nine subjects were excluded because they did not meet inclusion criteria. Mean age was 67.09 (95% CI 62.82, 71.37), and 10 subjects (31.25%) were female. and presenting NIHSS was 5.28 (95% CI 3.97, 6.58). Baseline characteristics including history of coronary artery disease, atrial fibrillation, diabetes mellitus including hemoglobin A1C, hypertension, hyperlipidemia including LDL, stroke, intracranial hemorrhage, tobacco use, anti‐thrombotic use, presenting systolic blood pressure, presenting blood glucose, last known normal were assessed. Three subjects received IV thrombolytics. All subjects (n = 32) had normal CT perfusion maps (kappa = 1).

Conclusions
Mismatch was not identified on CT perfusion in all subjects with small vessel disease stroke using conventional CT perfusion map protocols, that could have been useful in potentially guiding therapeutic optimization of hemodynamics. Larger, prospective studies are needed to validate our results.