Subacute Infarction Research Articles

Fatal rhabdomyolysis and fulminant myocarditis with malignant arrhythmias after one dose of ipilimumab and nivolumab.

Immune checkpoint inhibitors (ICIs) related myocarditis is a rare complication of modern immunotherapy. It can present as an asymptomatic subclinical condition or full-blown fulminant myocarditis with malignant arrythmias and cardiogenic shock. Myositis/rhabdomyolysis and/or myasthenic symptoms can be present concomitantly. We present a case of fatal fulminant myocarditis presenting with cardiac arrythmias and severe systolic dysfunction, with accompanying rhabdomyolysis after the first dose of ipilimumab and nivolumab immunotherapy. First working diagnosis of subacute late presenting acute myocardial infarction (ACS) was incorrect and the correct diagnosis was established only after additional testing and consultation. Treatment consisted of high-dose corticosteroids, intravenous immunoglobulins, sedation with mechanical ventilation, antibiotic coverage, hemodialysis, and sustained low-efficiency daily diafiltration (SLEDD) with CytoSorb or TheraNova membranes, and intra-aortic balloon pump mechanical cardiac support. No tangible improvement in the condition was observed during the whole treatment period and the patient died on the sixth day of intensive care treatment.

NIMG-43. INFARCTION RADIOLOGICALLY MIMICKING INTRA-AXIAL BRAIN TUMORS

Abstract There are several reports of brain lesions that radiologically mimicking the brain tumors. The abscess is representative lesion of resembling the intra-axial tumors in brain MRI. However, cerebral infarction is not a common lesion that resembles a brain tumor and can be easily distinguished from a brain tumor in MRI. Here, we represented the two cases of pathologically diagnosed infarction that radiologically suspected gliomas. A 67-year-old man presented with left side weakness and memory impairment. Brain MRI revealed the rim enhancing lesion radiologically suspected glioma. Navigation guided biopsy was performed and final pathological diagnosis was subacute infarction. A-41-year-old man represented the right side weakness. MRI showed the enhancing nodular lesion with perilesional edema. Surgical excision was performed and pathological diagnosis was infarction. Although advancement of brain imaging techniques, it is difficult to accurately discriminate the intracerebral lesions utilizing the MRI. Further comprehensive study should be executed for more precise differentiation of infarction and brain tumors.

8386 The Evolving Face of The Great Masquerader - Panhypopituitarism Associated with Neurosyphilis

Abstract Disclosure: M. Yabe: None. Z. Lin: None. F. Joseph: None. G. Philip: None. R. Silver: None. L. Callejas: None. J. Giunta: None. Untreated syphilis is on the rise in the United States. The CDC reported syphilis cases in newborns have increased 10-fold over a decade in November 2023, signifying the emergence of untreated infections. Pituitary involvement in syphilis is a very rare phenomenon, and endocrinological investigation is often overlooked. This will be the second reported case of neurosyphilis with pituitary involvement in a non-HIV infected patient. A 45-year-old female with no significant past medical history was admitted to the hospital with progressive neurological symptoms of intermittent left-side headache, hearing loss with tinnitus, and gait instability. Postcontrast MRI Brain revealed multifocal leptomeningeal enhancement involving supratentorial and infratentorial regions. Thickening of the enhanced pituitary infundibulum was also noted. Subsequent RPR titer showed 1:16 and lumbar puncture revealed CSF-VDRL titer 1:32, with pleocytosis 83 cells/uL, CSF-glucose 19 mg/dL, and CSF-protein 370 mg/dL. The patient completed Penicillin G 4 million/units intravenous every 4 hours for 14 days, with repeat MRI showing significant interval decrease in previously described extensive supratentorial and infratentorial leptomeningeal enhancement. However, there is no record of her sexual partner receiving treatment. The patient was readmitted one year later after a fall while displaying dysmetria. MRI Brain with contrast revealed a small subacute infarct along the right frontal corona radiata and pituitary gland measuring up to 1.2 cm in craniocaudal dimension compared to 0.4 cm on the prior exam. This prompted evaluation of pituitary hormones: FSH 0.8 IU/L, LH <0.3 IU/L, and ACTH 6.3 pg/mL, with normal serum growth hormone and prolactin levels. Further investigation revealed morning cortisol 2.5 ug/dL, thyrotropin < 0.2 uIU/mL, and free thyroxine 0.63 ng/dL. Radiological evidence is suspicious of inflammatory etiology of the pituitary gland. The patient was discharged with endocrinology follow-up and plan to perform a pituitary gland biopsy as an outpatient for confirmatory result. The association of neurosyphilis and hypophysitis leading to panhypopituitarism in a non-HIV infected patient was first reported in 2015. Since then, there remains limited research regarding their association due to rarity of pituitary involvement in neurosyphilis. With untreated syphilis on the rise and increased availability of MRI, clinicians should expect to encounter more cases of neurosyphilis with pituitary involvement in the future. Early detection of panhypopituitarism in those with positive CSF-VDRL titer could lead to better clinical outcomes. It is paramount that these cases are documented to emphasize pituitary involvement in neurosyphilis and encourage a low threshold to initiate endocrinological testing in the future. Presentation: 6/3/2024

Symptomatic Cerebellar Thrombosed Developmental Venous Anomaly: A Case Report

Abstract Background With the rising prevalence of advanced neuroradiological imaging, detection of incidental developmental venous anomalies (DVAs) is more commonplace. DVAs are rarely symptomatic (<2%). Typically, symptoms arise due to flow-related complications or mechanical effects. Of particular concern is venous thrombosis, a frequent flow-related complication, which can cause venous ischemia or haemorrhage. Thus, early recognition and intervention is important. Methods We describe a case of a 54-year-old male, with background of hypertension, presenting three days after sudden onset headache, ataxia, and diplopia. Initial clinical examination revealed bidirectional horizontal gaze-evoked nystagmus, skew deviation, and decreased temperature sensation of the left face. Ophthalmological examination identified left inferior rectus limitation. Results Initial non-contrast CT brain identified hypoattenuation in the right pons, suggestive of sub-acute infarction. Secondary prevention was initiated. Subsequent MRI performed 5 days later revealed hyperattenuation on T2 and FLAIR in the pons, right middle cerebellar peduncle, and right cerebellar hemisphere without restricted diffusion. SWI sequences identified an abnormal venous structure in the right cerebellum, with increased signal within it, suggestive of thrombus. The patient was diagnosed with a thrombosed DVA with associated venous oedema. Symptoms had resolved on dual antiplatelet therapy, without anticoagulation. Conclusion This case highlights the potential for DVAs, generally considered a benign entity, to become symptomatic with associated parenchymal damage and a rare, but important, stroke mimic. Moreover, it underscores the pivotal role of MRI imaging; while a CT scan might have led to the assumption of a subacute infarct, MR imaging led to a complete re-evaluation of the diagnosis in this case.

Extensive Multilabel Classification of Brain MRI Scans for Infarcts Using the Swin UNETR Architecture in Deep Learning Applications.

To distinguish infarct location and type with the utmost precision using the advantages of the Swin UNEt TRansformers (Swin UNETR) architecture. The research employed a two-phase training approach. In the first phase, the Swin UNETR model was trained using the Ischemic Stroke Lesion Segmentation Challenge (ISLES) 2022 dataset, which included cases of acute and subacute infarcts. The second phase involved training with data from 309 patients. The 110 categories result from classifying infarcts based on 22 specific brain regions. Each region is divided into right and left sides, and each side includes four types of infarcts (acute, acute lacunar, subacute, subacute lacunar). The unique architecture of Swin UNETR, integrating elements of both the transformer and u-net designs with a hierarchical transformer computed with shifted windows, played a crucial role in the study. During Swin UNETR training with the ISLES 2022 dataset, batch loss decreased to 0.8885±0.1897, with training and validation dice scores reaching 0.4224±0.0710 and 0.4827±0.0607, respectively. The optimal model weight had a validation dice score of 0.5747. In the patient data model, batch loss decreased to 0.0565±0.0427, with final training and validation accuracies of 0.9842±0.0005 and 0.9837±0.0010. The results of this study surpass the accuracy of similar studies, but they involve the issue of overfitting, highlighting the need for future efforts to improve generalizability. Such detailed classifications could significantly aid physicians in diagnosing infarcts in clinical settings.

THE OUTCOME OF COGNITIVE THERAPY IN PATIENTS WITH FIRST-EVER STROKE AND RECURRENT STROKE

Background: Vascular dementia (VaD) is the second most prevalent type of dementia that impacts elderly adults, succeeding Alzheimer's disease. In contrast to Alzheimer's disease, Vascular Dementia (VaD) presents a wide range of cognitive changes, which are greatly influenced by the specific neural regions that are impacted by vascular pathology. The incidence of dementia in adults with a prior history of stroke is 30%, demonstrating a frequency that is 3-5 times more than those without any discernible stroke-related impairments. In addition, the intensity or frequency of strokes may contribute to a decrease in cognitive reserve in persons with vascular dementia. Case Report: We presented two cases of VaD. The first case was a 62-year-old man with a history of ischemic stroke without sequelae a year before the complaints of frequent forgetfulness and cognitive impairment. Neuropsychological examination showed neurocognitive disturbances in orientation, attention, memory, and visuospatial domain with impaired daily activities function. The MRI result showed senile brain atrophy with chronic infarction on the right temporoparietooccipital lobe, left side mesencephalon, right side pons accompanied by cortical laminar necrosis on the right frontal lobe and left temporoparietal lobe. The second case was a 79-year-old man with history of recurrent ischemic stroke (three times since 2021-2022) with sequelae of left hemiparesis and complaints of frequent forgetfulness and cognitive impairment in the last 1 year. Neuropsychological examination showed neurocognitive disturbances in orientation, attention, and visuospatial domain with impaired daily activities function. The MRI result showed subacute multiple lacunar infarctions in right insular cortex, right frontotemporal lobe cortex, right corona radiata, with multiple chronic infarcts on the right frontotemporoparietal lobe, right corona radiata, right internal genu capsule, right lateral periventricular anterior horn, pons, right left cerebellum, also senile brain atrophy. Both patients were diagnosed as VaD and given donepezil 1x10mg and memantine 1x5mg to treat the cognitive impairment. Both cases showed improvements after 6 months of therapy with MMSE from 17 to 28, MoCA-INA from 12 to 22 and MMSE from 19 to 23, MoCA-INA from 14 to 21 respectively. Discussion: The probability of acquiring vascular dementia (VaD) was strongly associated with the incidence and frequency of strokes. The prevalence of newly developed dementia after the initial stroke is approximately 10%, which increases to 30% with recurrent strokes. The likelihood of experiencing cognitive impairment and dementia after a stroke is primarily determined by the specific attributes of the stroke. While pharmacological therapy largely focuses on cognitive impairment, other factors, such as the stroke's characteristics, might contribute to neuronal and molecular abnormalities that result in cognitive loss. Two instances were shown, both demonstrating enhancements, with the initial instance, involving primary strokes, exhibiting a superior outcome compared to the subsequent instance with recurring strokes. A more profound or recurring stroke has the potential to reduce cognitive reserve, hence potentially heightening vulnerability to neurodegenerative disorders, either directly or by means of modifications in social contacts or lifestyle, which can subsequently affect cognitive performance. Conclusion: Recurrent stroke plays a role in reducing cognitive reserve and increasing the risk of dementia. Patients with VaD have shorter life expectancy, thus the severity of VaD is best managed by providing optimum acute stroke care and recurrent stroke prevention.

A Drive Interrupted: Stroke of the Anterior Choroidal Artery – A Case Report

The anterior choroidal artery (AChA) is the most distal branch of the internal carotid artery (ICA) The ACHA is significant because it supplies important structures in the brain, including the optic tract, anterior portion of cerebral peduncle, lateral geniculate body, uncus, globus pallidus, posterior and superficial areas of the thalamus, and the retrolenticular and posterior portions of the internal capsule on the same side as the artery. Isolated strokes involving the AChA are rare and can result in HHH Syndrome, consisting of contralateral hemiplegia, hemisensory loss, and homonymous hemianopia. Features which distinguish an AChA infarction from larger arterial pathology are lack of headache and lack of depressed level of consciousness in subacute infarction, and usually lack of aphasia acutely. The etiology remains controversial, with proposed mechanisms including cardioembolic, large-vessel atherosclerosis, dissection of the ICA, small-vessel occlusion, and cryptogenic causes. Herein, the authors report a case of an isolated AChA infarction resulting in a right-sided, pure motor hemiparesis with no sensory or vision loss, highly suggestive of cardioembolic origin, with the evaluation of the patient, and eventual treatment strategy.

Effect of visual feedback balance system combined with digital treadmill on gait kinematics in patients with subacute cerebral infarction.

Effect of visual feedback balance system combined with digital treadmill on gait kinematics in patients with subacute cerebral infarction.

Chronic Lymphocytic Inflammation with Pontine Perivascular Enhancement Responsive to Steroids (CLIPPERS) Mimicking Posterior Circulation Infarction

CLIPPERS is a rare inflammatory condition of the central nervous system. It is pathologically characterised by white matter perivascular lymphohistiocytic infiltrate with or without parenchymal extension. A male patient in mid sixties presented with dysarthria and facial numbness underwent an MRI brain which supported a diagnosis of a subacute posterior circulation infarct. The patient re-presented with worsening of symptoms and a repeat MRI revealed changes atypical for ischaemia and consistent with CLIPPERS. Our case represents a common presentation of a very rare condition.

One and a Half Syndrome and Internuclear Ophthalmoplegia as Neuro-Ophthalmological Manifestations in Patients with Brainstem Stroke: A Case Series

Background: Brainstem stroke syndrome accounts for 10-15% of all types of strokes, which may result in relatively rare neuroophthalmological manifestations. The aim of this case report is to report findings of one and a half syndrome (OAHS) and internuclear ophthalmoplegia in a patient with brainstem stroke.
 Case presentation: First case, female, 56 years old, came with sudden weakness on the right side of the body. One and a half syndrome was found, namely when asked to glance to the left, conjugate gaze palsy was obtained horizontally, and when asked to glance to the right, there was adduction inability of the left eye (ipsilateral). Right eye abduction was normal with present nystagmus. Paresis of right central CN. VII, XII was present, along with hemiparesis dextra (contralateral). Head CT scan shows hemorrhage in pons and intraventricular. Second case, female, 65 years old, came with a protruding mouth, vertigo, and sudden double vision Internuclear ophthalmoplegia was present, namely an adduction inability of the left eye (ipsilateral) when asked to glance to the right. Right eye abduction was normal with present nystagmus. no abnormalities were seen in the primary position and when asked to glance to the left. Paresis of right peripheral CN. VII, hemiparesis and right (contralateral) hemihypesthesia was present. MRI shows multiple chronic infarcts as well as subacute infarcts in bilateral parietal and pons.
 Conclusion: Clinical knowledge is necessary for topic determination, rehabilitation process and evaluation.

Brain Diffusion in Brainstem Infarctions and Lesion Segmentation using Fluidattenuation Inversion Recovery: A Diagnostic Accuracy Study

Introduction: Diffusion can efficiently detect infratentorial and brainstem infarctions. Fluid-attenuation Inversion Recovery (FLAIR) is a widely used Magnetic Resonance Imaging (MRI) technique for the segmentation of brain lesions and strokes. Aim: To investigate the sensitivity of the Lesion Prediction Algorithm (LPA) within the Lesion Segmentation Tool (LST) in the automated segmentation of acute and subacute brainstem infarctions. Materials and Methods: This study was a retrospective diagnostic accuracy study where 24 patients with brainstem infarctions were referred from the Emergency Department to the Department of Radiodiagnosis at Kasr Alainy Hospital, Cairo University, Egypt. The study was conducted from September 2016 to June 2023. It included 24 patients (14 males and 10 females) with acute and subacute brainstem infarctions. MRI of the brain and diffusion were performed on all patients. Automated segmentation of brainstem infarctions using FLAIR was conducted in all cases. Manual and segmented volumes of brainstem infarctions were calculated. Sensitivity and accuracy of the LPA within the LST in automated segmentation of acute and subacute brainstem infarctions were evaluated. Pearson correlation was used to correlate volumes of White Matter Lesion (WML) burden in patients with brainstem infarctions and patients’ age. Results: The mean age of the participants was 51.75±11.95 years. The sensitivity of the LPA in automated segmentation of acute and subacute brainstem infarctions was 63.6% and 76.9%, respectively. An insignificant correlation (r=0.08; p-value=0.68) between the volumes of WML burden in patients with brainstem infarctions and patients’ age was noted. Conclusion: The sensitivity of the automated method in the segmentation of subacute brainstem infarctions was higher than that in acute brainstem infarctions.

Acquired Cerebral Achromatopsia Secondary to Occipital Stroke

Background: Acquired cerebral achromatopsia, a form of color vision impairment, is infrequently reported and often results from injuries to the occipital cortex. Case Presentation: We detail a case of a middle-aged women with vascular risk factors who visited the emergency department with blurred vision and disturbances in color perception, characterized as an inability to differentiate colors. A notable finding in her neurological examination was homonymous hemianopia. Hyperacute magnetic resonance imaging revealed a subacute infarction in the right occipital lobe. As she was outside the treatment window for alteplase and invasive interventions, she received aspirin and clopidogrel as treatment. Discussion: Patients with posterior circulation strokes often present with non-specific symptoms, which can lead to delayed diagnoses and treatment. Acquired cerebral achromatopsia, the inability to perceive color after acute brain injury, is a rare phenomenon associated with PCA stroke that has not been well studied yet. It usually involves the ventral occipitotemporal cortex in V4 complex, which anatomically is theorized to be the brain's color center. A comparison was made between two instances of acquired cerebral achromatopsia. In the first case, a 60-year-old woman displayed hemi-achromatopsia in the right visual field. In the second case, a 74-year-old woman suffered two strokes. The first stroke on the left hemisphere resulted only in a right homonymous hemianopia with normal color perception; however, upon the occurrence of the second stroke on the right hemisphere, she developed full field achromatopsia. The contrasting presentations of these cases after lesions in the ventral posterior regions of their left hemisphere suggests a hypothesis that individual differences might exist in the hemispheric laterality of color centers in the brain. Our patient experienced a right subacute occipital stroke; however, she exhibited bilateral achromatopsia. The exact cause of this full field achromatopsia from this specific lesion remains uncertain, but her presentation might support the hypothesis. Conclusion: Posterior circulation stroke infarctions often present with nonspecific symptoms making timely diagnosis and management challenging. Achromatopsia is an infrequent and subtle manifestation of posterior circulation infarctions that warrant further investigations and management.

The value of hyperintense acute reperfusion marker sign for evaluation of subacute cerebral infarction

The value of hyperintense acute reperfusion marker sign for evaluation of subacute cerebral infarction

Imaging of Vertebral Artery Dissection in Children: An Underrecognized Condition with High Risk of Recurrent Stroke.

Vertebral artery dissection (VAD) is a common cause of a rare condition, pediatric posterior circulation arterial ischemic stroke (PCAIS). VAD is clinically important due to the risk of multifocal and continuing infarcts from artery-to-artery thromboembolism, with the potential for occlusion of arteries that perfuse the brainstem. Early diagnosis is important, as recurrent stroke is a common effect of VAD in children. Although the relative efficacies of different treatment regimens for VAD in children remain unsettled, early initiation of treatment can mitigate the risk of delayed stroke. Clinical diagnosis of PCAIS may be delayed due to multiple factors, including nonspecific symptoms and the inability of younger patients to express symptoms. In fact, subacute or chronic infarcts are often present at initial imaging. Although the most common cause of isolated PCAIS is VAD, imaging of the cervical arteries has been historically underused in this setting. Cervical vascular imaging (MR angiography, CT angiography, and digital subtraction angiography) for VAD must be optimized to detect the sometimes subtle findings, which may be identified at initial or follow-up imaging. Osseous variants of the craniocervical junction and upper cervical spine and other extrinsic lesions that may directly injure the vertebral arteries or lead to altered biomechanics have been implicated in some cases. The authors review characteristic imaging features and optimized imaging of VAD and associated PCAIS and related clinical considerations. Identification of VAD has important implications for evaluation, treatment, and imaging follow-up, as this condition may result in progressive arteriopathy and recurrent stroke. © RSNA, 2023 Supplemental material is available for this article. Quiz questions for this article are available through the Online Learning Center.

Quiescent-yet-excitable pluripotent stem cell-derived cardiomyocytes engraft without fatal arrhythmias in minipig and primates

Abstract Background Pluripotent stem cell-derived cardiomyocyte (PSC-CM) transplantation is a promising therapy for subacute myocardial infarction (MI), but transient engraftment-related arrhythmia (EA) is major barrier to clinical development (1, 2). We hypothesize that PSC-CM genetically edited to remove automaticity but otherwise functionally intact will engraft in vivo with greater arrhythmic safety. Methods Combinatorial CRISPR/Cas9 genome editing to screen for electrically quiescent PSC-CM yielded a line deficient in the depolarization-associated genes HCN4, CACNA1H, and SLC8A1, combined with overexpression of the hyperpolarization-associated gene KCNJ2. Initially, we transplanted 150 million (n=3) and 500 million gene-edited (n=2) and 150 million wildtype (n=7) PSC-CMs into a minipig model of EA, and we monitored the animals for up to seven weeks on continuous ECG for arrythmia without anti-arrhythmic therapy. In a second study, we transplanted 750 million gene-edited (n=2) and wildtype (n=1) PSC-CMs into sub-acutely infarcted Macaca nemestrina primates. Sham transplant (n=1) was also performed, and all animals were observed for up to three months with immunosuppression and beta-blocker/amiodarone therapy. Results Gene-edited PSC-CM successfully engrafted and structurally coupled with the host myocardium of minipigs (Figure 1) and nonhuman primates (Figure 2). No significant EA occurred after transplanting edited PSC-CM at the 150 million dose, whereas brief EA (<24 hours) was observed and well tolerated at the higher 500 million dose. All five minipigs survived to prespecified timepoints without complication. Conversely, wildtype PSC-CM controls demonstrated uncontrolled and fatal ventricular tachycardia (VT). Of the seven WT control minipigs, only four survived (43% mortality); three expired or were euthanized due to unstable VT or ventricular fibrillation. Arrythmia burden for both 150 and 500 million doses were significantly reduced compared to the 150 million wildtype dose in the first 30-days post-transplant (p<0.0001 for both). We then tested edited PSC-CM in a clinically relevant nonhuman primate model of sub-acute myocardial infarction using standard medical therapy including modest antiarrhythmic therapy. No arrythmia was noted in both nonhuman primates dosed with 750 million edited PSC-CM whereas significant arrhythmia was observed with wildtype despite beta blocker and amiodarone therapy. All pig and primate grafts were structurally coupled with host myocardium. Conclusion Genetically-edited PSC-CM without pacemaker-like activity significantly reduced arrythmia burden and prevented arrhythmic death in a dose-escalation study in minipig. No arrhythmia was observed in a clinically relevant nonhuman primate model of cardiac remuscularization for sub-acute myocardial infarction. This study supports continued investigation of this novel strategy to improve safety and tolerability of PSC-CM transplantation.Edited PSC-CM transplant in minipigEdited PSC-CM transplant in primates

Abstract 15057: miR-132 Inhibitor CDR 132L Attenuates Cardiac Remodeling by Exhibiting Anti-Fibrotic Effects

Introduction: Increased cardiac expression levels of miRNA miR-132 have been associated with pathological cardiac remodeling including cardiac fibrosis. As a selective inhibitor for miR-132, the synthetic antisense oligonucleotide CDR132L, is capable to reverse cellular pathology and restore normal heart function. Pharmacological inhibition of miR-132 as well as genetic knockout has been shown to protect mice from transverse aortic constriction induced cardiac remodeling including interstitial fibrosis. Methods and Results: Treatment effects of CDR132L were investigated in several different pig models of ischemic and non-ischemic heart failure (HF) with the aim to further elucidate CDR132L’s mode of action and confirm species-independent effects on fibrotic remodeling. In a pig model of subacute post myocardial infarction (MI) induced HF, CDR132L was administered on day 3 and day 28 by intravenous (IV) or intracoronary (IC) infusion at doses of 1, 5 and 10 mg/kg and followed until day 56. In a chronic post-MI HF large animal model, beneficial effects were confirmed in a 6-month study comparing 5 monthly and 3 monthly repeated IV administrations of 5 mg/kg CDR132L starting one month post-MI. Further, CDR132L was tested in a porcine model of percutaneous aortic constriction by implantation of a reduction stent in the thoracic aorta and two IC injections of CDR132L on day 0 and day 28 followed for 56 days. As part of the pharmacodynamic analyses in these models, paraffin sections of cardiac tissue from the left ventricular remote region were stained with picrosirius red (PSR) and fibrosis was assessed based on collagen quantity. Analysis of fibrosis in PSR-staining revealed that the degree of interstitial fibrosis was significantly reduced in CDR132L treatment groups compared to placebo between 22% and 61%. Moreover, results of the first-in-human safety and tolerability study of CDR132L in patients with stable HF of ischemic origin (NCT04045405) showed encouraging positive trends for relevant cardiac fibrosis biomarkers. Conclusion: By blocking aberrant miR-132 expression, CDR132L is capable to halt and reverse pathological cardiac remodeling partly due to its anti-fibrotic effects.

Abstract 12088: Left Ventricular Non-Compaction, Coronary Artery Fistula, and Infective Endocarditis: A Rare Combination

Description of Case: A 48-year-old man underwent echocardiography for multifocal subacute infarctions found on brain MRI. No intracardiac shunts were found, but prominent LV trabeculae raised suspicion of LV non-compaction (LVNC). LV ejection fraction was 53%, and LV volume was within upper-normal range. Cardiac MRI confirmed these findings, although non-compacted:compacted myocardium ratio was 1.9. (Panel A-B) A right coronary artery to LV fistula was also diagnosed. (Panel C-D) The patient was followed-up uneventfully, but 10 months later was admitted after a generalized seizure episode. Brain MRI detected multiple new hemorrhagic infarcts, and echocardiography revealed a 10.8mmх10.1mm mobile mass and high-speed diastolic flow near the basolateral LV wall. (Panel E-F) Gemella morbillorum was identified on two blood cultures. The patient underwent surgery for fistula closure and vegetation resection. Vegetation pathology and culture however was negative for bacterial growth. Paroxysmal atrial fibrillation was also detected, before discharge with full recovery. Discussion: LVNC and coronary artery fistula (CAF) are both caused by arrest in embryonic myocardial compaction. Despite a hypothetical common origin, reports of co-occurrence are extremely rare. This is the first to report the association of a mild form of LVNC and a single large CAF. This is also the first to report infective endocarditis due to CAF by G. morbillorum . G. morbillorum infective endocarditis is rare, subacute in course, and causes significant destruction. The extensive, prolonged embolism found here has not been reported in other cases of CAF-associated infective endocarditis and may be due to G. morbillorum .

Abstract 121: Misdiagnosis in a case of pediatric stroke

Introduction Pediatric patients presenting with atypical stroke symptoms pose a diagnostic challenge, which often causes delays in management. Around a quarter of pediatric stroke patients will present with new onset seizures. We report this case to emphasize the importance of early consideration of ischemia as a differential diagnosis. We also want to emphasize the collaborative approach between pediatric and adult neurologists in challenging cases. Methods Case report Results A 15‐year‐old male presented to an outside hospital for new onset seizure. The patient later mentioned that he had difficulty writing the morning of the seizure. Initial blood work, CBC, CMP, urine analysis and toxicology were unremarkable. A second seizure occurred while in the ED. CT head revealed a questionable area of decreased attenuation in the left frontal lobe, felt to be artifact. Patient was transferred to our hospital for higher level of care. MRI of the brain showed gyriform signal abnormality within the left frontal lobe with restricted diffusion, no abnormal enhancement. Serum MOG, NMDA, LGI1, NMO antibodies were sent. LP was done and there was no evidence of infection. MRI of the C, T and L spine were unremarkable. CTA/CTV of the head was done and there was no evidence of vessel abnormalities or sinus thrombosis. Patient was started on high dose steroids for possible autoimmune etiology on hospital day 2. On Hospital Day 3, the case was re‐evaluated, and the possibility of infarction was proposed. The case was discussed with an adult vascular neurology attending physician, thus further imaging was obtained. CT Perfusion of Brain revealed a subacute left frontal infarct and possible dural AVF. A diagnostic cerebral angiography revealed enhanced capillary blush consistent with shunt in region of left peri‐Sylvian infarct. There was no evidence of other vascular malformations. A hypercoagulable panel was unremarkable. The patient was discharged on Hospital Day 6 on Vimpat and aspirin with outpatient follow‐up. Echo revealed a PFO on Valsalva maneuver. MRI spectroscopy revealed depressed creatine peak, low NAA and a high choline peak in the left frontal opercular T2 hyperintensity ‐ findings consistent with an evolving infarct with increased choline due to gliosis. He is planned for PFO closure and has not had further recurrent seizures. Conclusion According to Hollist et al., pediatric stroke incidence is 2.5‐13 per 100,000 children per year [1]. There are thousands of stroke misdiagnoses every year [2]. Stroke misdiagnosis is more likely in younger patients [2, 3]. 60% of pediatric stroke patients will end up with disability and half will have a decreased quality of life [4]. Misdiagnosis also results in misutilization of health care resources. Similar to our case, a collaborative approach between adult stroke neurologists and pediatric neurologists, where pediatric stroke neurologists are not available, helps avoid stroke misdiagnosis. As a result, this helps better patient outcomes and avoids preventable morbidity and mortality.

Abstract 268: Validation of an automated method to assess 24‐hour infarct volume in stroke patients

Introduction In stroke patients, accurate infarct volume assessment at 24 hours typically requires manual segmentation of lesions that often are not well defined. We aimed to validate an automated machine learning algorithm (MethinksFIV) specifically trained to automatically segment and measure subacute infarcts on non‐contrast CT (NCCT) scans. Methods We retrospectively studied stroke patients with a large vessel occlusion prospectively admitted to a comprehensive stroke center. The final infarct volume was segmented on the 24h NCCT manually (man‐FIV) and with the automated method (auto‐FIV). Both measurements were correlated with clinical outcomes. Results We included 346 patients. On 24h‐NCCT median auto‐FIV was lower than man‐FIV (8.6 ml [2.3‐40.7] vs. 16.9 ml [1.1‐70.8], p<0.001). Auto‐FIV and man‐FIV were highly correlated (r=0.8; p<0.001; mean dice coefficient of 0.61). The Auto‐FIV correlated better than man‐FIV with 24h (r=0.54 vs. r=0.51, both p<0.001) and discharge NIHSS (r=0.59 vs r=0.54, both p<0.001). An increase of 1 ml in auto‐FIV was associated with an increase in the odds of higher ordinal mRS at three months (OR=1.01 95%CI 1.01‐1.02, p<0.001). Auto‐FIV was a better predictor of mRS>2 at three months (OR: 1.02 95%CI 1.01‐1.13, p=0.002) than manual segmentation (OR=1.01, 95%CI 1.00‐1.01, p=0.01). In a multivariable analysis, only auto‐FIV remained a significant predictor of mRS>2 at three months (aOR: 1.03 95% CI 1.01‐1.05, p=0.004). Conclusion An automated method to measure subacute infarct volumes in stroke patients is accurate and correlates well with further clinical outcomes. The method appears to outperform manual segmentation and may be used to facilitate infarct characterization in large clinical trials.

Abstract 109: Endonasal Endoscopic Approach Associated Cerebral Vasospasm and Management: A Case Report

Introduction Endoscopic endonasal approach(EEA) techniques have been increasingly utilized and have been associated with development of cerebrospinal fluid(CSF) leak, meningitis, diabetes insipidus post‐operatively. Cerebral vasospasm following EEA has rarely been described. Here, we describe the clinical course and management of a patient who underwent EEA for encephalocele repair whose course was complicated by postoperative subarachnoid hemorrhage(SAH) and cerebral vasospasm. Methods n/a Results Case Presentation: 40 year old female with past medical history significant for cerebral venous sinus stent on aspirin, CSF rhinorrhea secondary to right nasal encephalocele s/p endoscopic transnasal transethmoidal repair with nasoseptal flap reconstruction and lumbar drain placement eleven days prior presented with speech difficulties and right sided weakness. On exam, patient was noted to have mild right hemiparesis and expressive aphasia. MRI brain showed subacute infarcts in left greater than right frontal lobes, corpus collosum and right anterior perforated substance. MRA head demonstrated multifocal arterial stenosis. In light of postoperative CT head showing SAH in the basilar, perimesencephalic, prepontine cisterns, interhemispheric fissure and right frontal sulci as well as intraventricular hemorrhage in fourth ventricle, her presentation was thought to be secondary to cerebral vasospasm in the setting of postoperative SAH. She was treated with intravenous hydration, permissive hypertension with head of bed in flat position and transferred for further evaluation. On arrival, she continued have mild right hemiparesis and aphasia. Repeat CTA head/neck and CT perfusion showed severe stenosis of bilateral M1 segments and left greater than right A1 segments as well as ischemic penumbra in left ACA/MCA watershed territory. Diagnostic cerebral angiogram showed bilateral severe A1 stenosis and mild to moderate bilateral M1 and supraclinoid ICA stenosis which improved with intra‐arterial verapamil. She was started on nimodipine. Systolic blood pressure was augmented with vasopressors for goal of 150‐180mmHg. Daily TCDs were followed. She developed worsening right leg weakness following day, thus she was taken for repeat diagnostic cerebral angiogram during which time she was re‐administered intra‐arterial verapamil with improvement in vasospasm. After the second treatment, she had improvement in speech and motor strength. Systolic blood pressure goal was gradually normalized. She was noted to have incidental left internal jugular (IJ) vein thrombosis for which anticoagulation was held in the setting of recent neurosurgical procedure and SAH. Workup for vasculitis and hypercoagulability was unrevealing. Lumbar puncture demonstrated 13 WBC/cu mm with lymphocytic predominance(90%), 23 RBC/cu mm, glucose 89mg/dl, protein 30mg/dl. CSF cultures were negative. Pleocytosis in CSF was attributed to recent neurosurgical procedure. Her neurological exam improved to baseline on hospital day(HD) 9.On HD12, she was found to have left common femoral deep venous thrombus in addition to the left IJ thrombus. Anticoagulation with low dose heparin infusion was started which was transitioned to apixaban on discharge. She was discharged home on HD20. Conclusion We report a case of EEA associated with severe multifocal cerebral vasospasm secondary to postoperative SAH that was successfully treated with induced hypertension, oral nimodipine and intra‐arterial verapamil as an adjunct therapy with an excellent outcome.