Atrial Fibrillation In Embolic Stroke Research Articles

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 – 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 – 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.

Abstract TP223: Predicting Atrial Fibrillation in Embolic Stroke of Unknown Source

Background: A considerable portion of patients with embolic stroke of unknown source(ESUS)are later found to have occult atrial fibrillation (AF). Studies have shown that prolonged outpatient cardiac monitoring increases the chances of AF detection and impacts choice of antithrombotic therapy. The Brown ESUS-AF Score, a prediction tool utilizing age and left atrial enlargement has previously shown promise in predicting AF in ESUS patients. In this study we aimed to externally validate the Brown ESUS-AF score and compare its performance against a random forest classifier. Methods: We included all patients with ESUS who underwent an inpatient stroke evaluation followed by outpatient cardiac monitoring between October 9,2015-March 31,2023. To validate the Brown ESUS-AF score, our cohort was divided between those who developed AF during follow-up versus those who did not. To develop the random forest classifier, we included demographics, medical comorbidities, lab records, echocardiographic and electrocardiographic findings. We did 80/20 train-test split to fine tune the model, and we identified features that had the greatest performance contribution. Results: Of 468 patients, 97(20.7%) patients had occult AF. AF patients were older(68.6±13.0 vs 60.1±15.6;p=0.0001), had a higher left atrial (LA) volume index(30.6±12.3 vs 26.2±10.0;p=0.0001) and larger LA diameter(3.8 ± 0.7 vs 3.5 ± 0.7;p=0.002) compared to those who did not develop AF. We found that a Brown ESUS-AF score of≥2 had lower sensitivity in our patient cohort than the original development cohort (42%vs63%). In comparing our random forest classifier to the Brown ESUS-AF score, our model had higher c-statistic (0.71vs0.64). The most important features we identified are age, LAVI, PR and QT Interval, triglyceride level and platelets. Conclusion: Our machine learning model incorporating 52 variables performed better than the Brown ESUS-AF score in predicting AF in our large and diverse ESUS cohort.

Atrial fibrillation in embolic stroke of undetermined source: role of advanced imaging of left atrial function.

Atrial fibrillation (AF) is detected in over 30% of patients following an embolic stroke of undetermined source (ESUS) when monitored with an implantable loop recorder (ILR). Identifying AF in ESUS survivors has significant therapeutic implications, and AF risk is essential to guide screening with long-term monitoring. The present study aimed to establish the role of left atrial (LA) function in subsequent AF identification and develop a risk model for AF in ESUS. We conducted a single-centre retrospective case-control study including all patients with ESUS referred to our institution for ILR implantation from December 2009 to September 2019. We recorded clinical variables at baseline and analysed transthoracic echocardiograms in sinus rhythm. Univariate and multivariable analyses were performed to inform variables associated with AF. Lasso regression analysis was used to develop a risk prediction model for AF. The risk model was internally validated using bootstrapping. Three hundred and twenty-three patients with ESUS underwent ILR implantation. In the ESUS population, 293 had a stroke, whereas 30 had suffered a transient ischaemic attack as adjudicated by a senior stroke physician. Atrial fibrillation of any duration was detected in 47.1%. The mean follow-up was 710 days. Following lasso regression with backwards elimination, we combined increasing lateral PA (the time interval from the beginning of the P wave on the surface electrocardiogram to the beginning of the A' wave on pulsed wave tissue Doppler of the lateral mitral annulus) [odds ratio (OR) 1.011], increasing Age (OR 1.035), higher Diastolic blood pressure (OR 1.027), and abnormal LA reservoir Strain (OR 0.973) into a new PADS score. The probability of identifying AF can be estimated using the formula. Model discrimination was good [area under the curve (AUC) 0.72]. The PADS score was internally validated using bootstrapping with 1000 samples of 150 patients showing consistent results with an AUC of 0.73. The novel PADS score can identify the risk of AF on prolonged monitoring with ILR following ESUS and should be considered a dedicated risk stratification tool for decision-making regarding the screening strategy for AF in stroke.

Monitoring for atrial fibrillation prior to patent foramen ovale closure after cryptogenic stroke.

Patients who had a cryptogenic stroke (CS) suspected to be causally related to a patent foramen ovale (PFO) are candidates for percutaneous PFO closure. In such patients, it is important to screen for atrial fibrillation (AF). Limited guidance is available regarding AF monitoring strategies in CS patients with PFO addressing optimal monitoring technology and duration. To provide a narrative review of cardiac rhythm monitoring in CS patients considered for PFO closure, including current practices, stroke recurrences after CS, findings from monitoring studies in CS patients, and predictors for AF detection published in the literature. To propose a personalized strategy for cardiac monitoring in CS patients, accounting for aspects predicting AF detection. AF detection in CS patients is predicted by age, left atrial enlargement, prolonged PR interval, frequent premature atrial contractions, interatrial conduction block, diabetes, prior brain infarctions, leukoaraiosis, elevated B-type natriuretic peptide (BNP)/N-terminal pro B-type natriuretic peptide (NT-proBNP) levels, and a family history of AF, as well as composed scores (e.g. CHA2DS2-VASc, atrial fibrillation in embolic stroke of undetermined source (AF-ESUS)). The causal role of the PFO may be accounted for by the risk of paradoxical embolism (RoPE) score and/or the PFO-Associated Stroke Causal Likelihood (PASCAL) classification. A personalized approach to AF detection in CS patients is proposed, accounting for the likelihood of AF detection and aimed at obtaining sufficient confidence regarding the absence of AF in patients considered for PFO closure. In addition, the impact of high-risk PFO features on the monitoring strategy is discussed.

Atrial cardiopathy predicts detection of atrial fibrillation in embolic stroke of undetermined source: real-life data.

Atrial cardiopathy (AC) is more frequent in patients with embolic stroke of undetermined source (ESUS) than in patients with non-cardioembolic stroke. The aim of this work was to describe AC in patients with ESUS and to study its impact on detection of atrial fibrillation (AF) during follow-up. This is an observational study of 123 consecutive ESUS patients and 55 ESUS patients from a previous cohort. AC was defined according to the presence of one or more of the following criteria: severe left atrial enlargement, p-wave terminal force in lead V1 > 5000 μVxms, and excessive premature atrial complexes. Unadjusted and adjusted survival analyses for the occurrence of AF and stroke or transient ischemic attack (TIA) were performed. Diagnostic performance of AC for the detection of AF was analyzed. Among 178 patients with ESUS, those with AC (42.7%) were older (p < 0.001), and more frequently had hypertension (p = 0.001) and lower total cholesterol levels (p = 0.001) than patients without AC. The detection of AF during follow-up (median 34months, interquartile range = 12.8-64) was higher in patients with AC (hazard ratio = 7.00, 95% confidence interval = 2.01-24.39, p = 0.002). This association persisted after adjusting for age, arterial hypertension, and other vascular risk factors. The c-statistic for detection of AF during follow-up for AC was 0.719. There were no differences in stroke or TIA recurrence between groups with and without AC. ESUS patients with AC have different baseline clinical characteristics than patients without AC and have a higher detection of AF during follow-up.

Artificial Intelligence-Enabled ECG to Identify Silent Atrial Fibrillation in Embolic Stroke of Unknown Source

ObjectivesEmbolic strokes of unknown source (ESUS) are common and often suspected to be caused by unrecognized paroxysmal atrial fibrillation (AF). An AI-enabled ECG (AI-ECG) during sinus rhythm has been shown to identify patients with unrecognized AF. We pursued this study to determine if the AI-ECG model differentiates between patients with ESUS and those with known causes of stroke, and to evaluate whether the AF prediction by AI-ECG among patients with ESUS was associated with the results of prolonged ambulatory cardiac rhythm monitoring. Materials and methodsWe reviewed consecutive patients admitted with acute ischemic stroke to a comprehensive stroke center between January 2018 and August 2019 and employed the TOAST classification to categorize the mechanisms of ischemia. Use and results of ambulatory cardiac rhythm monitoring after discharge were gathered. We ran the AI-ECG model to obtain AF probabilities from all ECGs acquired during the hospitalization and compared those probabilities in patients with ESUS versus those with known stroke causes (apart from AF), and between patients with and without AF detected by ambulatory cardiac rhythm monitoring. ResultsThe study cohort had 930 patients, including 263 patients (28.3%) with known AF or AF diagnosed during the index hospitalization and 265 cases (28.5%) categorized as ESUS. Ambulatory cardiac rhythm monitoring was performed in 226 (85.3%) patients with ESUS. AF probability by AI-ECG was not associated with ESUS. However, among patients with ESUS, the probability of AF by AI-ECG was associated with a higher likelihood of AF detection by ambulatory monitoring (P = 0.004). A probability of AF by AI-ECG greater than 0.20 was associated with AF detection by ambulatory cardiac rhythm monitoring with an OR of 5.47 (95% CI 1.51–22.51). ConclusionsAI-ECG may help guide the use of prolonged ambulatory cardiac rhythm monitoring in patients with ESUS to identify those who might benefit from anticoagulation.

Left Ventricular Abnormality and Covert Atrial Fibrillation in Embolic Stroke of Undetermined Source.

Aims: The relationship between left ventricular (LV) function and AF detection in embolic stroke of undetermined source (ESUS) patients with insertable cardiac monitors (ICMs) remains unclear. We investigated the association between LV function and AF detection in patients with ESUS after ICMs implantation. Methods: We enrolled patients with ESUS who underwent ICMs implantation from September 2016 to September 2020 using a single-center, prospective registry. LV systolic and diastolic functions were assessed on precordial echocardiography by LV fractional shortening (LVFS) and average E/e’, respectively. Associations between characteristics of LV function and detection of AF by ICMs were analyzed. Results: Participants comprised 101 patients (median age, 74 years; male, 62%). During a median follow-up period of 442 days (interquartile range (IQR), 202–770 days), AF was detected in 24 patients (24%). Median duration from ICMs implantation to AF detection was 71 days (IQR, 13–150 days). When LVFS and E/e’ were dichotomized by cutoff value, each of low LVFS (＜35.5%; adjusted hazard ratio (HR), 4.77; 95% confidence interval (CI), 1.77–12.9) and high E/e’ (≥ 8.65; adjusted HR, 4.56; 95%CI, 1.17–17.7) were independently associated with AF detection after adjusting for age and sex. When patients were divided into four groups according to dichotomized LVFS and E/e’, the combination of low LVFS and high E/e’ was independently associated with AF. Conclusions: In patients with ESUS after ICMs implantation, the LV characteristics of low LVFS and high E/e’ were associated with AF detection.

Association of Electrocardiographic P-Wave Markers and Atrial Fibrillation in Embolic Stroke of Undetermined Source

Background: Several P-wave indices are thought to represent underlying atrial remodeling and have been associated with ischaemic stroke even in the absence of atrial fibrillation (AF). However, the utility of these P-wave indices in predicting outcomes in patients with embolic stroke of undetermined source (ESUS) has not been studied. The aim of this study is to examine these different P-wave indices towards predicting new-onset AF and stroke recurrence in a cohort of patients with ESUS, thereby demonstrating the value of these electrocardiographic markers for stroke risk stratification. Methods: Between October 2014 and October 2017, consecutive patients diagnosed with ESUS were followed for new-onset AF and ischaemic stroke recurrence. The various P-wave indices, namely, the P-terminal force in the precordial lead V1 (PTFV1), P-wave duration, P-wave dispersion, interatrial blocks, and P-wave axis, were assessed on the initial electrocardiogram on presentation and studied for their relation to eventual AF detection and recurrent stroke. Results: 181 ischaemic stroke patients with ESUS were recruited and followed up for a median duration of 2.1 years. An abnormal PTFV1 was associated with occult AF detection but not with recurrent ischaemic strokes. No significant association was observed between the other P-wave indices with either occult AF or stroke recurrence. Conclusion: PTFV1 is associated with AF detection but not recurrent strokes in ESUS patients and can be a useful electrocardiographic marker for further risk stratification in ESUS patients.

Editors' note: Carotid plaques and detection of atrial fibrillation in embolic stroke of undetermined source

In “Carotid plaques and detection of atrial fibrillation in embolic stroke of undetermined source,” Ntaios et al. studied 777 patients with embolic stroke of undetermined source (ESUS) and found that the presence of ipsilateral nonstenotic carotid plaque was associated with a significantly lower likelihood for atrial fibrillation. Siegler et al. questioned the modality used to identify nonstenotic carotid plaque and paroxysmal atrial fibrillation, given that this affects incidence rates. Furthermore, they noted that although the authors commented on the frequency of conditions during which atrial fibrillation was detected (such as routine ECG, stroke recurrence, and myocardial infarction), it would have been useful to compare the incidence rates for patients with and without plaque. Ntaios responded that unfortunately, they did not have access to information about the technique used to diagnose carotid plaque or atrial fibrillation and that they did not think it was appropriate to compare the incidence of conditions during which atrial fibrillation was detected without this information. Lattanzi et al. commented that it would be useful to assess the relationship between plaques and atrial fibrillation and other variables, such as atrial cardiopathy, which has been shown to be inversely related to artery-to-artery strokes. Ntaios responded that they have performed additional analysis and hope to have their results published soon. It is clear that further research into workup and management of ESUS is needed. In “Carotid plaques and detection of atrial fibrillation in embolic stroke of undetermined source,” Ntaios et al. studied 777 patients with embolic stroke of undetermined source (ESUS) and found that the presence of ipsilateral nonstenotic carotid plaque was associated with a significantly lower likelihood for atrial fibrillation. Siegler et al. questioned the modality used to identify nonstenotic carotid plaque and paroxysmal atrial fibrillation, given that this affects incidence rates. Furthermore, they noted that although the authors commented on the frequency of conditions during which atrial fibrillation was detected (such as routine ECG, stroke recurrence, and myocardial infarction), it would have been useful to compare the incidence rates for patients with and without plaque. Ntaios responded that unfortunately, they did not have access to information about the technique used to diagnose carotid plaque or atrial fibrillation and that they did not think it was appropriate to compare the incidence of conditions during which atrial fibrillation was detected without this information. Lattanzi et al. commented that it would be useful to assess the relationship between plaques and atrial fibrillation and other variables, such as atrial cardiopathy, which has been shown to be inversely related to artery-to-artery strokes. Ntaios responded that they have performed additional analysis and hope to have their results published soon. It is clear that further research into workup and management of ESUS is needed.

Author response: Carotid plaques and detection of atrial fibrillation in embolic stroke of undetermined source.

Author response: Carotid plaques and detection of atrial fibrillation in embolic stroke of undetermined source.

Reader response: Carotid plaques and detection of atrial fibrillation in embolic stroke of undetermined source.

We read with great interest the article by Ntaios et al.,1 which demonstrated a lower cumulative probability of atrial fibrillation (AF) detection in patients with embolic strokes of undetermined source (ESUS) with ipsilateral nonstenotic carotid plaques compared with those without.

Reader response: Carotid plaques and detection of atrial fibrillation in embolic stroke of undetermined source.

We read with much interest the multicenter observational experience of Ntaios et al.1 regarding the incidence of atrial fibrillation among patients with embolic stroke of undetermined source (ESUS). The article added considerably to the increasing evidence regarding the heterogeneity of ESUS and the clinical relevance of nonstenotic carotid artery plaque.2,3 It may also assist in decision making regarding outpatient cardiac event monitoring.

Author response: Carotid plaques and detection of atrial fibrillation in embolic stroke of undetermined source.

I thank Dr. Lattanzi and Dr. Silvestrini for their interest in our work1 and their constructive suggestions. Several of the proposed analyses were already conducted and are currently under review in peer-reviewed journals. Hopefully, the results of these analyses will be publicly available soon.

Abstract WMP61: RNA Expression Signature to Diagnosis Stroke Etiology by Atrial Fibrillation versus Large Artery Atherosclerosis Cause: A BASE Clinical Trial Analysis

Background: Identifying atrial fibrillation in embolic stroke of ischemic stroke populations would be of significant clinical utility. Using the Biomarkers of Acute Stroke Etiology (BASE) trial (NCT02014896) dataset, our goal was to determine if blood gene expression signatures accurately differentiated patients with atrial fibrillation from large artery stroke patients. Methods: The BASE trial enrolled suspected stroke patients presenting to 20 hospitals within 24 hrs of symptom onset. Final gold standard diagnosis and stroke etiology were determined by an adjudication committee using all hospital data but blinded to RNA test results. Whole blood, obtained in PAXgene tubes, was frozen at -20C within 72 hrs and analyzed at a core lab (Ischemia Care, LLC, Dayton, OH) using Affymetrix HTA micro arrays. Approximately 38,000 genes on the HTA microarray were filtered to eliminate genes with low expression or high CV (&gt; 10%) when run on replicate samples leaving 9,513 potential signature genes. A two-way random forest classifier was built through cross validation of the training data resulting in a 23 gene diagnostic signature. Results: There were 58 patients enrolled between 18 and 24 hours of symptom onset, with NIHSS&gt;5, 27 (47%) with atrial fibrillation cause of stroke and 31 (53%) with large artery stroke; 64% were male, and median (IQR) age was 69.7 (62.8, 81.0). Median (IQR) time from symptoms to sample collection was 1323.5 (1208.8, 1381.3) minutes. Coexistent pathology at presentation was high blood pressure 49 (84%), hyperlipidemia 28 (48%), diabetes 9 (16%), and coronary artery disease 15 (26%). The panel was able to distinguish atrial fibrillation from large vessel stroke with a C-statistic 0.92 (0.55-1.0, 95% CI), sensitivity 0.90 (0.51-1.0, 95% CI) and specificity of 0.85. Conclusion: RNA expression differentiates strokes due to atrial fibrillation from large artery stroke and may have therapeutic and outcome implications in ischemic stroke populations.

Left atrial diameter thresholds and new incident atrial fibrillation in embolic stroke of undetermined source

Background and purposeWe analyzed consecutive patients with embolic stroke of undetermined source (ESUS) from three prospective stroke registries to compare the prognostic performance of different LAD thresholds for the prediction of new incident AF. MethodsWe calculated the sensitivity, specificity, positive prognostic value (PPV), negative prognostic value (NPV) and Youden's J-statistic of different LAD thresholds to predict new incident AF. We performed multivariate stepwise regression with forward selection of covariates to assess the association between the LAD threshold with the highest Youden's J-statistic and AF detection. ResultsAmong 675 patients followed for 2437 patient-years, the mean LAD was 38.5 ± 6.8 mm. New incident AF was diagnosed in 115 (17.0%) patients. The LAD threshold of 40mm yielded the highest Youden's J-statistic of 0.35 with sensitivity 0.69, specificity 0.66, PPV 0.27 and NPV 0.92. The likelihood of new incident AF was nearly twice in patients with LAD > 40 mm compared to LAD ≤ 40 mm (HR:1.92, 95%CI:1.24–2.97, p = 0.004). The 10-year cumulative probability of new incident AF was higher in patients with LAD>40 mm compared to LAD ≤ 40 mm (53.5% and 22.4% respectively, log-rank-test: 28.2, p < 0.001). The annualized rate of stroke recurrence of 4.0% in the overall population did not differ significantly in patient above vs. below this LAD threshold (HR:0.96, 95%CI:0.62–1.48, p = 0.85). ConclusionsThe LAD threshold of 40 mm has the best prognostic performance among other LAD values to predict new incident AF after ESUS. The diagnostic yield of prolonged cardiac rhythm monitoring in patients with LAD ≤ 40 mm seems low; therefore, such patients may have lower priority for prolonged cardiac monitoring.

Markers of endothelial pathology to support detection of atrial fibrillation in embolic stroke of undetermined source

A relevant part of embolic strokes of undetermined source (ESUS) is assumed to be cardiogenic. As shown previously, certain biomarkers of endothelial pathology are related to atrial fibrillation (AF). In this long-term follow-up study, we aimed to investigate whether these biomarkers are associated with subsequently diagnosed AF and with atrial cardiopathy. In 98 patients who suffered ischemic stroke of known and unknown origin L-arginine, Asymmetric (ADMA) and Symmetric Dimethylarginine (SDMA) have been measured on follow-up at least one year after index stroke. Stroke-diagnostics were available for all patients, including carotid Intima-Media-Thickness (CIMT) and comprehensive echocardiography studies. CIMT was larger in AF- compared with ESUS-patients (P < 0.001), independently from CHA2DS2VASC in the regression analysis (P = 0.004). SDMA-values were stable over time (P < 0.001; r = 0.788), whereas for ADMA moderate correlation with the initial values could be found (P = 0.007; r = 0.356). According to Kaplan-Meier-analyses, AF-detection rates were associated with CIMT (P = 0.003) and SDMA (P < 0.001). SDMA correlated with left atrial volume-index within the whole collective (P = 0.003, r = 0.322) and within the ESUS-subgroup (P = 0.003; r = 0.446). These associations were independent from CHA2DS2VASC and renal function in the regression analysis (P = 0.02 and P = 0.005, respectively). In conclusion, these results highlight SDMA and CIMT as potential markers of atrial cardiopathy and AF in ESUS-patients.

Advanced interatrial block: A predictor of covert atrial fibrillation in embolic stroke of undetermined source

AimsOne third of ischemic strokes are of unknown etiology. Interatrial block (IAB) is a marker of atrial electromechanical dysfunction that may predispose to the development of atrial fibrillation (AF). We hypothesized that IAB, especially in its advanced form, could be a marker of covert AF in patients with embolic stroke of undetermined source (ESUS). MethodsWe reviewed a single center cohort of ESUS patients with no prior history of AF. According to P-wave analysis of baseline ECG we distinguished 3 groups: normal P-wave duration (P-wave < 120 ms), partial IAB (P-IAB, P-wave ≥ 120 ms) and A-IAB (A-IAB, P-wave ≥ 120 ms with biphasic morphology in inferior leads). Follow-up was done 1, 6 and 12 months after discharge; then every 6 months. AF episodes, frequent premature atrial contractions (PACs) (>1%) and atrial tachyarrhythmias (runs of >3 consecutive PACs) were detected on 24 h Holter. The primary endpoint was new-onset AF detection on follow-up by any means. ResultsA high prevalence of both P-IAB (n = 30, 40%) and A-IAB (n = 23, 31%) was found in 75 ESUS patients. After a 521 day mean follow-up, 14 patients (19%) were diagnosed of AF. A-IAB independently predicted AF diagnosis (p =0.042) on follow-up. 24 h Holter analysis showed greater frequency of PACs and atrial tachyarrhythmia episodes in patients with IAB (p = 0.0275). ConclusionsIn this hypothesis-generating study, A-IAB in the setting of ESUS is an independent risk predictor of covert AF. Although additional randomized clinical trials are warranted, A-IAB identifies ESUS patients with advanced atrial disease that could potentially benefit from early oral anticoagulation in secondary prevention.

P4139Prediction of atrial fibrillation in embolic stroke of unknown source

Abstract Background Atrial fibrillation (AF) is one of the leading cardiogenic causes for embolic stroke of unknown source (ESUS). Its incidence is growing with patients' age. Detection and rule out of AF is complex and cumbersome. The best method is an implantable loop recorder (ILR). In patients elder than 60 years, incidence of AF is reported incongruently and reliable patient characteristics that can predict a low or high risk for AF are scarce. Purpose This study reports real life incidences of AF in a group of patients undergoing ILR after ESUS. It aims to depict age dependency of AF and to identify potential confounding factors. Methods In a single center study, we analysed 111 patients (age=62±13 years, nmale=65) who received an ILR in our centre following ESUS. Patient characteristics, brain imaging, hemodynamic monitoring, blood pressure, electrocardiography, holter ecg and echocardiography data from the initial hospital stay and ILR follow-up over a mean of 460 days were analysed. Primary endpoint was the recording of AF during follow-up. Results AF was detected in 23% of all patients. Patients with AF were significantly elder than those without AF (p=0.01). Incidence of AF was in Patients &lt;60y: 14%, 60–69y: 13%, 70–79y: 45%, &gt;80y: 67%. We observed a significant difference in AF incidence comparing patients younger and elder than 70 years (p=0.034). Both, CHADS-Vasc (p=0.036) and HATCH-scores (p=0.018) were higher in the AF group while the simple CHADS2 Score missed significance (p=0.068). PQ duration was longer in AF patients (p=0.022) and baseline heart rate at admission was lower (p=0.027). NIHSS scores were lower in the AF group at admission (2.97 vs. 4.10; p=0.049) but due to less neurological improvement in the AF group, this difference faded until dismission (1.09 vs 1.79 p=ns). Conclusions In our real life ILR group following ESUS, strongest predictor of AF was age. Pivot point rather was at 70 than at 60 years of age.

Association between Bilateral Infarcts Pattern and Detection of Occult Atrial Fibrillation in Embolic Stroke of Undetermined Source (ESUS) Patients with Insertable Cardiac Monitor (ICM)

Background and AimsIncreasingly, insertable cardiac monitors (ICM) have been used to detect Atrial Fibrillation (AF) in patients with cryptogenic stroke or embolic strokes of undetermined source (ESUS). We aim to examine the characteristics of these patients who were subsequently found to have AF. MethodsWe studied 83 consecutive patients who were comprehensively evaluated using neuroimaging and vessel imaging (computed tomography angiography, magnetic resonance angiography, or transcranial and extracranial Doppler sonography) to have met the previously established ESUS criteria. All 83 patients had ICM implanted between 2015 and 2017. All patients were followed up for at least 1 year, with a median follow-up period of 1.5 ± .5 years. We compared the baseline clinical, laboratory, echocardiographic, neuro-imaging profiles, and clinical outcomes in terms of functional recovery, recurrent stroke, and mortality in patients with and without detected AF. ResultsAF detection rate in this ESUS cohort was 12% over the study period. Patients with detected AF were associated with bilateral infarcts pattern at presentation (30% versus 5.5%, P = .035). Infarcts involving multiple vascular territories was not significantly associated with the detection of AF. There were no significant differences in the other clinical characteristics and outcomes between the AF group compared to the group without detected AF. Echocardiographic parameters including left ventricular ejection fraction and left atrial diameter were also not shown to be significantly different. ConclusionOur study found that a neuroimaging profile of bilateral infarcts was associated with AF detection using insertable cardiac monitor in ESUS patients. Larger prospective studies are needed to validate our findings.

Septal total atrial conduction time for prediction of atrial fibrillation in embolic stroke of unknown source: a pilot study

BackgroundSubclinical atrial fibrillation (AF) is the underlying cause in a relevant part of patients with embolic stroke of unknown source (ESUS). This pilot study aims to identify novel echocardiographic parameters predicting AF subsequently detected in patients originally hospitalized with ESUS.Methods and resultsPatients with acute ischemic stroke [baseline diagnosis of ESUS (n = 69), stroke of macro- or microvascular cause (n = 16/25), stroke caused by AF (n = 5)] and controls with paroxysmal AF without acute ischemic stroke (n = 22) as well as healthy controls of young and old age (n = 21/17) in sinus rhythm were included (overall n = 175). Echocardiography was performed in all participants. Prolonged Holter-ECG-monitoring was performed in all stroke patients. In the overall cohort, septal total atrial conduction time (sPA-TDI), left atrial (LA) volume index to tissue Doppler velocity (LAVI/a`) and second negative peak strain rate during LA contraction (SRa), representing echocardiographic parameters of LA remodelling and function, were statistically significant different in patients with and without AF and predictive for subclinical AF (multivariate regression analysis: sPA-TDI: HR 1.06 [1.04–1.08], p < 0.001; LAVI/a`: HR 0.85, [0.74–0.97], p = 0.02; SRa: HR 2.35 [0.9–5.5], p = 0.05). Multivariate Cox regression analysis revealed sPA-TDI as an independent predictor of AF in ESUS patients (sPA-TDI: HR 1.10 [1.04–1.17], p = 0.001). A sPA-TDI of 126 ms strictly discriminated between presence and absence of subclinical AF within 48 h after initiation of Holter-ECG-monitoring in ESUS patients.ConclusionssPA-TDI seems to be a strong independent predictor of subclinical AF in patients hospitalized for ESUS and might support risk-stratified clinical decision making in these patients.Graphic abstractSeptal Total Atrial Conduction Time (sPA-TDI) determined by echocardiography for prediction of Atrial Fibrillation in Embolic Stroke of Unknown Source (ESUS).