Embolic Stroke Of Undetermined Source Research Articles

Acute ischemic stroke with a diagnosis of Marfan syndrome: A report of 3 cases in multifaceted settings.

Marfan syndrome (MFS), which is a dominantly inherited connective tissue disease resulting from a mutation in the FBN1 gene, exhibits variable manifestations affecting the cardiovascular, musculoskeletal, ophthalmologic, and pulmonary systems. Notably, neurologic deficiency, which involves ischemic or hemorrhagic stroke, is a rare but severe manifestation. The safety of rt-PA treatment for ischemic stroke caused by MFS is still under discussion. In the current report, we discuss 3 atypical MFS cases presented as acute ischemic stroke, compared to those exhibiting cardiovascular and musculoskeletal abnormalities. Three patients were diagnosed with acute ischemic stroke accompanied by MFS based on clinical manifestations, imaging examinations, and genetic testings. The first case underwent intravenous thrombolytic therapy with rt-PA, the second case received antiplatelet therapy, and the third case received anticoagulant therapy and perfusion therapy. The neurologic deficiency of all three patients showed improvement upon discharge, and there were no symptoms of recurrence observed during the follow-up period. MFS is a rare etiology in young people with embolic stroke of undetermined source. Physicians should take MFS into consideration when they observe the characteristic symptoms during a consultation. The potential pathogenesis of ischemic stroke secondary to MFS may include cardio-embolism, arterial dissection, and hypoperfusion. Although intravenous thrombolysis is a promising therapy to treat acute ischemic stroke, further examinations should be conducted to rule out contraindications in patients with a suspicion of MFS.

Embolic strokes of undetermined source: a clinical consensus statement of the ESC Council on Stroke, the European Association of Cardiovascular Imaging and the European Heart Rhythm Association of the ESC.

One in six ischaemic stroke patients has an embolic stroke of undetermined source (ESUS), defined as a stroke with unclear aetiology despite recommended diagnostic evaluation. The overall cardiovascular risk of ESUS is high and it is important to optimize strategies to prevent recurrent stroke and other cardiovascular events. The aim of clinicians when confronted with a patient not only with ESUS but also with any other medical condition of unclear aetiology is to identify the actual cause amongst a list of potential differential diagnoses, in order to optimize secondary prevention. However, specifically in ESUS, this may be challenging as multiple potential thromboembolic sources frequently coexist. Also, it can be delusively reassuring because despite the implementation of specific treatments for the individual pathology presumed to be the actual thromboembolic source, patients can still be vulnerable to stroke and other cardiovascular events caused by other pathologies already identified during the index diagnostic evaluation but whose thromboembolic potential was underestimated. Therefore, rather than trying to presume which particular mechanism is the actual embolic source in an ESUS patient, it is important to assess the overall thromboembolic risk of the patient through synthesis of the individual risks linked to all pathologies present, regardless if presumed causally associated or not. In this paper, a multi-disciplinary panel of clinicians/researchers from various backgrounds of expertise and specialties (cardiology, internal medicine, neurology, radiology and vascular surgery) proposes a comprehensive multi-dimensional assessment of the overall thromboembolic risk in ESUS patients through the composition of individual risks associated with all prevalent pathologies.

Predictors of atrial fibrillation after embolic stroke of undetermined source in patients with implantable loop recorders.

In patients with embolic stroke of undetermined source (ESUS), underlying subclinical atrial fibrillation (AF) is often suspected. Previous studies identifying predictors of AF have been limited in their ability to diagnose episodes of AF. Implantable loop recorders enable prolonged, continuous, and therefore more reliable detection of AF. The aim of this study was to identify clinical and ECG parameters as predictors of AF in ESUS patients with implantable loop recorders. 101 ESUS patients who received an implantable loop recorder between 2012 and 2020 were included in this study. Patients were followed up regularly on a three-monthly outpatient interval. During a mean follow-up of 647 ± 385days, AF was detected in 26 patients (26%). Independent risk factors of AF were age ≥ 60years (HR 2.753, CI 1.129-6.713, p = 0.026), P-wave amplitude in lead II ≤ 0.075mV (HR 3.751, CI 1.606-8.761, p = 0.002), and P-wave duration ≥ 125ms (HR 4.299, CI 1.844-10.021, p < 0.001). In patients without risk factors, the risk of developing AF was 16%. In the presence of one risk factor, the probability increased only slightly to 18%. With two or three risk factors, the risk of AF increased to 70%. AF was detected in about one in four patients after ESUS in this study. A comprehensive evaluation involving multiple parameters and the existence of multiple risk factors yields the highest predictive accuracy for detecting AF in patients with ESUS.

Long-term outcomes of patients with embolic stroke of undetermined source according to subtype

The prognosis of patients with embolic stroke of undetermined source (ESUS) may vary according to the underlying cause. Therefore, we aimed to divide ESUS into subtypes and assess the long-term outcomes. Consecutive patients with acute ischemic stroke who underwent a comprehensive workup, including transesophageal echocardiography and prolonged electrocardiography monitoring, were enrolled. We classified ESUS into minor cardioembolic (CE) ESUS, arteriogenic ESUS, two or more causes ESUS, and no cause ESUS. Arteriogenic ESUS was sub-classified into complex aortic plaque (CAP) ESUS and non-stenotic (< 50%) relevant artery plaque (NAP) ESUS. A total of 775 patients were enrolled. During 1286 ± 748 days follow-up, 116 major adverse cardiovascular events (MACE) occurred (4.2 events/100 patient-years). Among the ESUS subtypes, CAP ESUS was associated with the highest MACE frequency (9.7/100 patient-years, p = 0.021). Cox regression analyses showed that CAP ESUS was associated with MACE (hazard ratio 2.466, 95% confidence interval 1.305–4.660) and any stroke recurrence (hazard ratio 2.470, 95% confidence interval, 1.108–5.508). The prognosis of ESUS varies according to the subtype, with CAP ESUS having the worst prognosis. Categorizing ESUS into subtypes could improve patient care and refine clinical trials.

Complex left appendage morphology is associated with Embolic Stroke of Undetermined Source.

Variations in the left atrial appendage (LAA) morphology are associated with different embolic risk in patients with atrial fibrillation (AF). Data are scarce regarding the association between LAA morphology and Embolic stroke of undetermined source (ESUS). Using cardiac computed tomography (CCT) scans, LAA morphology was categorized as either chicken wing (CW), cactus, windsock, or cauliflower. Furthermore, we examined the presence of large secondary lobes arising from the main lobe, considering their existence as indicative of a complex LAA morphology. LAA morphologies were compared between ESUS (n = 134) and AF patients (n = 120); and between ESUS patients with (n = 24) and without (n = 110) subsequent AF diagnosis during long-term follow-up. ESUS patients had a significantly higher prevalence of cauliflower morphology compared to AF group (52% vs 34%, respectively, p = 0.01); however, no significant difference was found between the groups when categorizing LAA morphology to either CW or non-CW. ESUS patients had significantly higher prevalence of large secondary lobes compared with AF patients (50% vs 29%, respectively, p = 0.001). When comparing ESUS patients with and without AF diagnosis during follow-up (20-48 months of follow-up, median 31 months), there were no significant differences in the prevalence of the "classical" morphologies, but large secondary lobes were significantly more prevalent among those without subsequent AF diagnosis. ESUS patients have a high prevalence of complex LAA morphology, which might be associated with an increased risk for thrombus formation even in the absence of AF.

The Role of Intrapulmonary Shunt (IPS) in Embolic Stroke of Undetermined Source (ESUS) (S34.007)

The Role of Intrapulmonary Shunt (IPS) in Embolic Stroke of Undetermined Source (ESUS) (S34.007)

PFO Closure in Older Patients with Embolic Stroke of Undetermined Source (P2-5.010)

PFO Closure in Older Patients with Embolic Stroke of Undetermined Source (P2-5.010)

MRI in the Evaluation of Cryptogenic Stroke and Embolic Stroke of Undetermined Source.

Cryptogenic stroke refers to a stroke of undetermined etiology. It accounts for approximately one-fifth of ischemic strokes and has a higher prevalence in younger patients. Embolic stroke of undetermined source (ESUS) refers to a subgroup of patients with nonlacunar cryptogenic strokes in whom embolism is the suspected stroke mechanism. Under the classifications of cryptogenic stroke or ESUS, there is wide heterogeneity in possible stroke mechanisms. In the absence of a confirmed stroke etiology, there is no established treatment for secondary prevention of stroke in patients experiencing cryptogenic stroke or ESUS, despite several clinical trials, leaving physicians with a clinical dilemma. Both conventional and advanced MRI techniques are available in clinical practice to identify differentiating features and stroke patterns and to determine or infer the underlying etiologic cause, such as atherosclerotic plaques and cardiogenic or paradoxical embolism due to occult pelvic venous thrombi. The aim of this review is to highlight the diagnostic utility of various MRI techniques in patients with cryptogenic stroke or ESUS. Future trends in technological advancement for promoting the adoption of MRI in such a special clinical application are also discussed.

Subtype-Specific Association of Mitochondrial DNA Copy Number With Poststroke/TIA Outcomes in 10 241 Patients in China.

Mitochondrial DNA copy number (mtDNA-CN) is associated with the severity and mortality in patients with stroke, but the associations in different stroke subtypes remain unexplored. We conducted an observational prospective cohort analysis on patients with ischemic stroke or transient ischemic attack enrolled in the Third China National Stroke Registry. We applied logistic models to assess the association of mtDNA-CN with functional outcome (modified Rankin Scale score, 3-6 versus 0-2) and Cox proportional hazard models to assess the association with stroke recurrence (treating mortality as a competing risk) and mortality during a 12-month follow-up, adjusting for sex, age, physical activity, National Institutes of Health Stroke Scale at admission, history of stroke and peripheral artery disease, small artery occlusion, and interleukin-6. Subgroup analyses stratified by age and stroke subtypes were conducted. The Third China National Stroke Registry enrolled 15 166 patients, of which 10 241 with whole-genome sequencing data were retained (mean age, 62.2 [SD, 11.2] years; 68.8% men). The associations between mtDNA-CN and poststroke/transient ischemic attack outcomes were specific to patients aged ≤65 years, with lower mtDNA-CN significantly associated with stroke recurrence in 12 months (subdistribution hazard ratio, 1.15 per SD lower mtDNA-CN [95% CI, 1.04-1.27]; P=5.2×10-3) and higher all-cause mortality in 3 months (hazard ratio, 2.19 [95% CI, 1.41-3.39]; P=5.0×10-4). Across subtypes, the associations of mtDNA-CN with stroke recurrence were specific to stroke of undetermined cause (subdistribution hazard ratio, 1.28 [95% CI, 1.11-1.48]; P=6.6×10-4). In particular, lower mtDNA-CN was associated with poorer functional outcomes in stroke of undetermined cause patients diagnosed with embolic stroke of undetermined source (odds ratio, 1.53 [95% CI, 1.20-1.94]; P=5.4×10-4), which remained significant after excluding patients with recurrent stroke (odds ratio, 1.49 [95% CI, 1.14-1.94]; P=3.0×10-3). Lower mtDNA-CN is associated with higher stroke recurrence rate and all-cause mortality, as well as poorer functional outcome at follow-up, among stroke of undetermined cause, embolic stroke of undetermined source, and younger patients.

Edoxaban for the treatment of hypercoagulability and cerebral thromboembolism associated with cancer: A randomized clinical trial of biomarker targets.

This study aimed compare efficacy of edoxaban and enoxaparin upon biomarkers of hypercoagulability in patients with cancer-related embolic stroke of undetermined source (ESUS). In this open-label, randomized, pilot trial, patients with cancer-related ESUS within 30 days of diagnosis were randomly assigned (1:1) to receive edoxaban (60 mg once daily) or enoxaparin (1 mg/kg twice daily) for 90 days. The primary endpoint was interval change of serum D-dimer level between days 0 and 7. The secondary endpoints were microembolic signals detected by transcranial Doppler at 7 and 90 days, the modified Rankin scale score, and stroke recurrence during 90 days. Safety outcomes included major bleeding and all-cause death at 90 days. Of 303 patients with ischemic stroke and cancer, 40 fully met enrollment criteria and were randomized. Baseline D-dimer levels were numerically higher in the edoxaban group (22.9 ± 15.9 μg/mL vs 16.9 ± 16.9 μg/mL). D-dimer level change (%) between days 0 and 7 was similar in the two groups (53.2 ± 25.7 vs 52.2 ± 52.0; P = 0.11). Microembolic signals were detected in 41.1% and 43.8% at baseline, 41.2% and 42.9% at day 7, and 25.0% and 28.6% at day 90 in the edoxaban and enoxaparin groups, respectively. Non-significantly higher major bleeding (35.0% vs 10.0%, P = 0.06) and 90-day mortality (40.0% vs 25.0%, P = 0.31) were noted in the edoxaban group. Edoxaban and enoxaparin were comparable with respect to the biomarkers of hypercoagulability and cerebral thromboembolism. Larger trials are warranted to compare effects of edoxaban and enoxaparin upon recurrent stroke and major bleeding in patients with cancer-related ESUS. clinicaltrials.gov Identifier: NCT03570281 (https://clinicaltrials.gov/ct2/show/NCT03570281).

Subclinical atrial fibrillation in embolic stroke of undetermined source: Management and stroke recurrence

Subclinical atrial fibrillation (SAF) represents the most prevalent underlying etiology detected after an embolic stroke of undetermined source (ESUS). Investigating SAF is strongly recommended during the diagnostic work-up. The efficacy of oral anticoagulant (OAC) therapy in reducing the risk of stroke recurrence post-SAF detection remains a conundrum. Thus, our study aimed to analyze the management of secondary antithrombotic prophylaxis and the rate of 12-month stroke recurrence in real-life ESUS patients. We retrospectively analyzed clinical, radiographic, and echocardiographic findings of patients with ESUS who underwent non-implantable 2-week electrocardiogram (ECG) monitoring after discharge. Episodes of SAF of any duration were considered diagnostic. Antithrombotic treatment at hospital discharge and after ECG monitoring, as well as 12-month recurrence, were registered. We compared the rate of stroke recurrence between patients with and without detection of SAF. One hundred and fifty-nine patients (75 females) with a median age of 73.5 (interquartile range [IQR] = 66.75 &amp;ndash; 79) years represented the study population. At hospital discharge, 96.9% of patients received antiplatelet therapy as secondary antithrombotic prophylaxis. SAF was detected in 82 patients (51.5%), and OAC was prescribed in 98.6% of them. The median time from stroke onset to OAC prescription was 143 (IQR = 94 &amp;ndash; 178) days. Overall, 12-month stroke recurrence occurred in eight patients (5%). The stroke recurrence rate was lower in patients prescribed OAC compared with those not prescribed it, although the difference was not significant (3.7% vs. 6.25%; P = 0.7202). In our study, OACs prescribed post-SAF detection in patients with ESUS reduced, but not significantly, the risk of stroke recurrence. Future research and prospective multicenter studies are warranted.

Association between Left Atrial Appendage Morphology and Clot Histology in Patients with Embolic Ischemic Stroke: An Exploratory Study.

Acute embolic ischemic stroke poses a significant healthcare challenge. Histological clot features' variability among patients with acute ischemic stroke treated by mechanical thrombectomy has potential implications for determining treatment and etiology. This study investigated the clot histological feature differences among patients who experienced cardioembolic stroke and embolic stroke of undetermined source with different left atrial appendage (LAA) morphologies. We conducted a prospective observational study involving 79 patients with acute embolic ischemic stroke undergoing mechanical thrombectomy. Computed tomography angiography images were used to classify LAA morphologies. An artificial intelligence algorithm assessed the clot fibrin and red blood cell contents. Patients with chicken-wing LAA morphology exhibited lower mean clot fibrin proportions than did those with non-chicken-wing morphology (p < 0.001). Linear regression analysis showed that chicken-wing LAA was significantly associated with a lower clot fibrin proportion (estimate, -0.177; 95% CI [-0.259, -0.096]; p < 0.001). The successful recanalization rate and first-pass effect between the groups did not differ significantly. The chicken-wing LAA morphological type is associated with lower clot fibrin contents, suggesting potentially different embolism mechanisms or diverse embolic sources, compared with the non-chicken-wing LAA types. Further studies are required to investigate this association.

Left atrial shape as a marker of atrial myopathy in embolic stroke of undetermined source.

Embolic Stroke of Undetermined Source (ESUS) results in significant morbidity. A left atrial (LA) myopathy is implicated in a proportion of these patients. We hypothesized that LA shape varies by cause of stroke (cardioembolic versus ESUS). 236 ischemic stroke, atrial fibrillation (AF) patients and controls were recruited prospectively. AF was classified as paroxysmal (PAF) or persistent AF (PersAF). Stroke patients comprised cardioembolic stroke (CE) secondary to AF and ESUS. There were 81 AF (47 PAF, 34 PersAF), 50 ESUS, 57 CE patients (subdivided into CE with PAF (CEpaf) and CE with PersAF (CEpers) and 48 controls. Echocardiographic parameters including LA volume, function, and shape/sphericity (3D LA-sphericity and 2D-derived LA-circularity, ellipticity, sphericity and eccentricity indices) were evaluated. Increased LA volume and sphericity with LA dysfunction was present in CE, AF and ESUS groups compared to controls. K-means cluster analysis demonstrated a spectrum of LA myopathy with controls at the lowest and CEpers and PersAF at the upper extremes, with ESUS, PAF and CEpaf being similar and falling between these extremes. After adjusting for age, sex and left ventricular (LV) and LA parameters, LA sphericity markers differentiated ESUS from controls (p < 0.01). Alterations in LA shape are present in ESUS, AF and CE patients, particularly increased spherical remodelling. The novel markers of LA sphericity proposed may identify LA myopathy in ESUS patients and potentially guide management for secondary prevention.

Use of wearable technology in cardiac monitoring after cryptogenic stroke or embolic stroke of undetermined source: a systematic review.

Prolonged cardiac monitoring after cryptogenic stroke or embolic stroke of undetermined source (ESUS) is necessary to identify atrial fibrillation (AF) that requires anticoagulation. Wearable devices may improve AF detection compared to conventional management. We aimed to review the evidence for the use of wearable devices in post-cryptogenic stroke and post-ESUS monitoring. We performed a systematic search of PubMed, EMBASE, Scopus and clinicaltrials.gov on 21 July 2022, identifying all studies that investigated the use of wearable devices in patients with cryptogenic stroke or ESUS. The outcomes of AF detection were analysed. Literature reports on electrocardiogram (ECG)-based (external wearable, handheld, patch, mobile cardiac telemetry [MCT], smartwatch) and photoplethysmography (PPG)-based (smartwatch, smartphone) devices were summarised. A total of 27 relevant studies were included (two randomised controlled trials, seven prospective trials, 10 cohort studies, six case series and two case reports). Only four studies compared wearable technology to Holter monitoring or implantable loop recorder, and these studies showed no significant differences on meta-analysis (odds ratio 2.35, 95% confidence interval [CI] 0.74-7.48, I2 = 70%). External wearable devices detected AF in 20.7% (95% CI 14.9-27.2, I2 = 76%) of patients and MCT detected new AF in 9.6% (95% CI 7.4%-11.9%, I2 = 56%) of patients. Other devices investigated included patch sensors, handheld ECG recorders and PPG-based smartphone apps, which demonstrated feasibility in the post-cryptogenic stroke and post-ESUS setting. Wearable devices that are ECG or PPG based are effective for paroxysmal AF detection after cryptogenic stroke and ESUS, but further studies are needed to establish how they compare with Holter monitors and implantable loop recorder.

Predictors of atrial fibrillation detection in embolic stroke of undetermined source patients with implantable loop recorder.

Covert atrial fibrillation (AF) is a predominant aetiology of embolic stroke of undetermined source (ESUS). Evidence suggested that AF is more frequently detected by implantable loop recorder (ILR) than by conventional monitoring. However, the predictive factors associated with occult AF detected using ILRs are not well established yet. In this study we aim to investigate the predictors of AF detection in patients with ESUS undergoing an ILR. This observational multi-centre study included consecutive ESUS patients who underwent ILR implantation. The infarcts were divided in deep, cortical infarcts or both. The infarction sites were categorized as anterior and middle cerebral artery, posterior cerebral artery with and without brainstem/cerebellum involvement. Multivariable logistic regression analysis was performed to investigate variables associated with AF detection. Overall, 3,000 patients were initially identified. However, in total, 127 patients who consecutively underwent ILR implantation were included in our analysis. AF was detected in 33 (26%) out of 127 patients. The median follow-up was 411 days. There were no significant differences in clinical characteristics and comorbidities between patients with and without AF detected. AF was detected more often after posterior cerebral artery infarct with brainstem/cerebellum involvement (p < 0.001) whereas less often after infarction in the anterior and middle cerebral artery (p = 0.021). Multivariable regression analysis demonstrated that posterior cerebral artery infarct with brainstem/cerebellum involvement was an independent predictor of AF detection. Our study showed that posterior circulation infarcts with brainstem/cerebellum involvement are associated with AF detection in ESUS patients undergoing ILR. Larger prospective studies are needed to validate our findings.

Artificial intelligence predicts undiagnosed atrial fibrillation in patients with embolic stroke of undetermined source using sinus rhythm electrocardiograms

BackgroundArtificial intelligence (AI)–enabled sinus rhythm (SR) electrocardiogram (ECG) interpretation can aid in identifying undiagnosed paroxysmal atrial fibrillation (AF) in patients with embolic stroke of undetermined source (ESUS). ObjectiveThe purpose of this study was to assess the efficacy of an AI model in identifying AF based on SR ECGs in patients with ESUS. MethodsA transformer-based vision AI model was developed using 737,815 SR ECGs from patients with and without AF to detect current paroxysmal AF or predict the future development of AF within a 2-year period. Probability of AF was calculated from baseline SR ECGs using this algorithm. Its diagnostic performance was further tested in a cohort of 352 ESUS patients from 4 tertiary hospitals, all of whom were monitored using an insertable cardiac monitor (ICM) for AF surveillance. ResultsOver 25.1-month follow-up, AF episodes lasting ≥1 hour were identified in 58 patients (14.4%) using ICMs. In the receiver operating curve (ROC) analysis, the area under the curve for the AI algorithm to identify AF ≥1 hour was 0.806, which improved to 0.880 after integrating the clinical parameters into the model. The AI algorithm exhibited greater accuracy in identifying longer AF episodes (ROC for AF ≥12 hours: 0.837, for AF ≥24 hours: 0.879) and a temporal trend indicating that the AI-based AF risk score increased as the ECG recording approached the AF onset (P for trend <.0001). ConclusionsOur AI model demonstrated excellent diagnostic performance in predicting AF in patients with ESUS, potentially enhancing patient prognosis through timely intervention and secondary prevention of ischemic stroke in ESUS cohorts.

A Simple Score for Predicting Paroxysmal Atrial Fibrillation in Patients with Embolic Stroke of Undetermined Source in a Tunisian Cohort Study.

The annualized recurrent stroke rate in patients with Embolic Stroke of Undetermined Source (ESUS) under antiplatelet therapy is around 4.5%. Only a fraction of these patients will develop atrial fibrillation (FA), to which a stroke can be attributed retrospectively. The challenge is to identify patients at risk of occult AF during follow-up. This work aims to determine clinical factors and electrocardiographic and ultrasound parameters that can predict occult AF in patients with ESUS and build a simple predictive score applicable worldwide. This is a single-center, registry-based retrospective study conducted at the stroke unit of Sahloul University Hospital, Sousse, Tunisia, between January 2016 and December 2020. Consecutive patients meeting ESUS criteria were monitored for a minimum of one year, with a standardized follow-up consisting of outpatient visits, including ECG every three months and a new 24-hour Holter monitoring in case of palpitations. We performed multivariate stepwise regression to identify predictors of new paroxysmal AF among initial clinical, electrocardiographic (ECG and 24-hour Holter monitoring) and echocardiographic parameters. The coefficient of each independent covariate of the fitted multivariable model was used to generate an integerbased point-scoring system. Three hundred patients met the criteria for ESUS. Among them, 42 (14%) patients showed at least one episode of paroxysmal AF during a median follow-up of two years. In univariate analysis, age, gender, coronary artery disease, history of ischemic stroke, higher NIHSS at admission and lower NIHSS at discharge, abnormal P-wave axis, prolonged P-wave duration, premature atrial contractions (PAC) frequency of more than 500/24 hours, and left atrial (LA) mean area of more than 20 cm2 were associated with the risk of occurrence of paroxysmal AF. We proposed an AF predictive score based on (1.771 x NIHSS score at admission) + (10.015 x P-wave dispersion; coded 1 if yes and 0 if no) + (9.841x PAC class; coded 1 if ≥500 and 0 if no) + (9.828x LA class surface; coded 1 if ≥20 and 0 if no) + (0.548xNIHSS score at discharge) + 0.004. A score of ≥33 had a sensitivity of 76% and a specificity of 93%. In this cohort of patients with ESUS, NIHSS at both admission and discharge, Pwave dispersion, PAC≥500/24h on a 24-hour Holter monitoring, and LA surface area≥20 cm2 provide a simple AF predictive score with very reasonable sensitivity and specificity and is applicable almost worldwide. An external validation of this score is ongoing.

Abstract TP259: Slower Early Mitral Inflow Velocity and Lesion in Anterior Circulation is Associated With Right-to-Left Shunt in Embolic Stroke of Undetermined Source Right-to-Left Shunt in Embolic Stroke of Undetermined Source

Background and Purpose: Right-to-left shunt (RLS) is one of the potential embolic sources in embolic stroke of undetermined source (ESUS), but the eligibility of conducting shunt study to detect RLS in ESUS is still unknown. To reveal clinical features associated with RLS in ESUS, we aimed to compare clinical features including transthoracic echocardiography findings and imaging findings with and without RLS in ESUS. Methods: Consecutive ischemic stroke patients in a comprehensive stroke center were screened between April 2013 and April 2023. Inclusion criteria were: 1) who fulfilled the ESUS criteria based on NAVIGATE-ESUS trial, 2) who underwent transesophageal echocardiogram, and 3) admitted 7 days from the onset. We compared clinical features, including transthoracic echocardiography findings and imaging findings such as lesion characteristics (size, cortical or subcortical, and anterior or posterior), between ESUS patients with RLS (RLS-ESUS) and without RLS (non RLS-ESUS). Results: We screened 2,304 consecutive ischemic stroke patients, including 225 ESUS patients (166 [74%] male, median age 64 years old). Of all, 76 patients had RLS (59 [78%] male, median age 62 years old, Figure A). RLS-ESUS showed higher frequency of anterior circulation lesion (RLS-ESUS vs. non RLS-ESUS; 84% vs. 71%, p = 0.035), slower early mitral inflow velocity (E) (51.6 vs. 54.9 cm/s, p = 0.021). In multivariable analysis, E (OR 0.83, 95%CI0.70-0.99, p = 0.037) and anterior circulation lesion (OR 2.23, 95%CI 1.08-4.62, p = 0.036) were independently associated with RLS-ESUS (Figure B). Conclusions: In ESUS patients, slower early mitral inflow velocity and lesion in anterior circulation was associated with RLS, suggesting shunt study should be conducted to reveal RLS in such patients.

Abstract 42: Validation of a New Plaque-RADS Classification System to a Cohort of Embolic Stroke of Undetermined Source Patients

Introduction: A new Plaque-RADS classification (I-IV) is proposed to categorize the degree of carotid plaque instability and risk of embolic ischemic stroke. We tested the Plaque-RADS classification in a cohort of patients with embolic stroke of undetermined source (ESUS) and imaged with neck CTAs. Methods: Patients with unilateral anterior circulation ischemic stroke due to ESUS and neck CTAs showing &lt;50% carotid stenosis were retrospectively identified. Carotid total plaque thickness and ulceration were scored by a neuroradiologist blinded to stroke side. A semiautomated segmentation software measured intraplaque hemorrhage (IPH) volumes. The Plaque-RADS classification is defined as: I: no plaque; II: plaque thickness &lt;3mm ; III: plaque thickness ≥ 3mm or ulcerated; and IV: plaque with IPH&gt;50mL irrespective of thickness. Prevalence of Plaque-RADS subtypes was analyzed ipsilateral versus contralateral to stroke side. The proportion of low (subtypes I/II) versus high-risk (III/IV) carotid plaques on the ipsilateral versus contralateral stroke-side was tested using a McNemar’s test. Results: Ninety-four patients (N=52 female, mean age 65.4; N=188 plaques) met criteria. Plaque-RADS distribution was classified as: Plaque-RADS I: 18.1%; II: 44.7%; III: 36.7% (III ulc : 1.6%); IV: 0.5%. High-risk Plaque-RADS subtypes were significantly more prevalent on the ipsilateral (42.6%) compared to the contralateral side of stroke (31.9%, p=0.008). Conclusions: Carotid plaque ipsilateral to stroke side showed a higher proportion of Plaque-RADS III/IV subtypes. The Plaque-RADS classification may be used to risk-stratify carotid plaque phenotypes in patients with ESUS.

Abstract WP287: AI-ECG Algorithm Outperforms CHA2DS2-VASc in Prediction of Occult Atrial Fibrillation Detection on Prolonged Cardiac Monitoring Following Cerebral Infarction

Introduction: Patients diagnosed with ischemic stroke routinely undergo prolonged cardiac telemetry (PCT) to evaluate for occult atrial fibrillation (AF), but this approach is limited by high cost and low yield. Clinical scores including CHA2DS2-VASc and CHARGE-AF can risk stratify patients but lack desired accuracy. Therefore, we aimed to evaluate an artificial intelligence (AI)-enabled ECG algorithm to predict AF detected by PCT after index stroke. Methods: This retrospective study included all adult patients with ischemic stroke evaluated at Mayo Clinic with baseline electrocardiogram (ECG) and PCT between 2018-2020. We recorded demographics, CHA2DS2-VASc score, CHARGE-AF score, stroke etiology, duration of PCT, and if PCT detected AF. ECGs were analyzed using the AI-ECG algorithm to determine AF likelihood. Stroke etiology was adjudicated using TOAST and embolic stroke of undetermined source (ESUS) definitions. The ability of the AI-ECG algorithm, CHA2DS2-VASc, and CHARGE-AF to predict AF detected by PCT was assessed via receiver operating characteristics analysis, calculating the area under curve (AUC) (c-statistic). Sensitivity and specificity analyses were performed for each tool using optimal cutoffs (using maximum Youden indices). Results: 863 patients were included; median age was 69 years, 496 (57.5%) were male, and 561 (65%) patients were categorized as ESUS. PCT detected AF in 85 (9.8%) patients. Median duration of cardiac telemetry was 30 (IQR 25-30) days. Sensitivity and specificity analyses are outlined in Table 1. The AI-ECG algorithm outperformed the CHA2DS2-VASc score (AUC 0.690 vs. 0.597, p=0.013), but was similar to the CHARGE-AF score (AUC 0.690 vs 0.651, p=0.233). Conclusions: Our AI-ECG algorithm demonstrated improved ability to predict AF detection on PCT after index stroke when compared to the CHA2DS2-VASc score, but was similar in performance to the CHARGE-AF score. All three methods had suboptimal accuracy.