The P-wave terminal force in embolic strokes of undetermined source

Atrial cardiomyopathy revisited-evolution of a concept: a clinical consensus statement of the European Heart Rhythm Association (EHRA) of the ESC, the Heart Rhythm Society (HRS), the Asian Pacific Heart Rhythm Society (APHRS), and the Latin American Heart Rhythm Society (LAHRS)

AIMS

The concept of "atrial cardiomyopathy" (AtCM) had been percolating through the literature since its first mention in 1972. Since then, publications using the term were sporadic until the decision was made to convene an expert working group with representation from four multinational arrhythmia organizations to prepare a consensus document on atrial cardiomyopathy in 2016 (EHRA/HRS/APHRS/SOLAECE expert consensus on atrial cardiomyopathies: definition, characterization, and clinical implication). Subsequently, publications on AtCM have increased progressively.

METHODS AND RESULTS

The present consensus document elaborates the 2016 AtCM document further to implement a simple AtCM staging system (AtCM stages 1-3) by integrating biomarkers, atrial geometry, and electrophysiological changes. However, the proposed AtCM staging needs clinical validation. Importantly, it is clearly stated that the presence of AtCM might serve as a substrate for the development of atrial fibrillation (AF) and AF may accelerates AtCM substantially, but AtCM per se needs to be viewed as a separate entity.

CONCLUSION

Thus, the present document serves as a clinical consensus statement of the European Heart Rhythm Association (EHRA) of the ESC, the Heart Rhythm Society (HRS), the Asian Pacific Heart Rhythm Society (APHRS), and the Latin American Heart Rhythm Society (LAHRS) to contribute to the evolution of the AtCM concept.

Embolic stroke of undetermined source: Focusing on atrial cardiopathy and patent foramen ovale

BACKGROUND

Atrial cardiopathy(AC) and patent foramen ovale (PFO) are two etiologies of embolic strokes of undetermined source (ESUS). We aimed to explore the relationship between them in ESUS.

METHODS

A total of 1146 participants were included from January 2019 to June 2022, which included the ESUS group and non-embolic stroke which includes LAA(large arterial atherosclerosis) + SAO(small artery occlusion) group. AC was defined as the presence of at least one of the following: PTFV1(P-wave terminal force in lead V1) > 4000 μV*ms in the electrocardiograms, NT-proBNP(N-terminal probrain natriuretic peptide) > 250 pg/mL in laboratory tests or LAD(left atrial diameter) > 3.8 cm for women and > 4.0 cm for men in cardiac ultrasound. The presence of PFO was assessed by transthoracic echocardiography, transcranial Doppler ultrasound, transesophageal echocardiography or cardiac MRI. PFO was considered pathogenic if the RoPE score was 7 to 10.

RESULTS

The prevalence of AC and PFO was higher in the ESUS group than the LAA + SAO group. The prevalence of AC was lower in ESUS patients with pathogenic PFO (37.9%) than those without PFO (68.4%) and with incidental PFO (64.0%) (p = 0.006). The prevalence of pathogenic PFO was lower in ESUS patients with AC than those without AC (6.0% vs. 17.8%, p = 0.006). The AUC(area under the curve) of PTFV1 for predicting ESUS was 0.724 [95%CI (0.686-0.762), p < 0.05)], indicating that PTFV1 the most valuable AC biomarker.

CONCLUSIONS

The prevalence of AC is inversely related to the prevalence of pathogenic PFO in ESUS patients. PTFV1 was the most valuable index to predict ESUS among the AC biomarkers.

Assessing atrial myopathy with cardiac magnetic resonance imaging in embolic stroke of undetermined source

BACKGROUND

Left atrial myopathy has been implicated in atrial fibrillation (AF)-related stroke and embolic stroke of undetermined source (ESUS).

OBJECTIVE

To use advanced cardiac magnetic resonance (CMR) imaging techniques, including left atrial (LA) strain and 4D flow CMR, to identify atrial myopathy in patients with ESUS.

METHODS

20 patients with ESUS and no AF or other cause for stroke, and 20 age and sex-matched controls underwent CMR with 4D flow analysis. Markers of LA myopathy were assessed including LA size, volume, ejection fraction, and strain. 4D flow CMR was performed to measure novel markers of LA stasis such as LA velocities and the LA residence time distribution time constant (RTDtc). These markers of LA myopathy were compared between the two groups.

RESULTS

There was no significant difference in: CMR-calculated LA velocities or LA total, passive or active ejection fractions between the groups. There was no significant difference in CMR-derived reservoir, conduit or contractile average longitudinal strain between the ESUS and control groups (22.9 vs 22.6%, p=0.379, 11.2 ± 3.5 vs 12.4 ± 2.6% p=0.224, 10.8 ± 3.2 vs 10.4 ± 2.3%, p=0.625 respectively). Similarly, RTDtc was not significantly longer in ESUS patients compared to controls (1.3 ± 0.2 vs 1.2 ± 0.2, p=0.1).

CONCLUSIONS

There were no significant differences in any CMR marker of atrial myopathy in ESUS patients compared to healthy controls, likely reflecting the multiple possible aetiologies of ESUS suggesting that the role LA myopathy plays in ESUS is smaller than previously thought.

Cryptogenic stroke as a working diagnosis: the need for an early and comprehensive diagnostic work-up

In the Nordic Atrial Fibrillation and Stroke (NOR-FIB) study, the causes of ischemic stroke were identified in 43% of cryptogenic stroke patients monitored with implantable cardiac monitor (ICM), but one-third of these patients had non-cardioembolic causes. These results suggest the need for an early and comprehensive diagnostic work-up before inserting an ICM.

Neutrophil-to-Lymphocyte Ratio Predicts Early Neurological Deterioration after Endovascular Treatment in Patients with Ischemic Stroke

The worsening of neurological status that occurs early after acute ischemic stroke (AIS) remains a serious issue, and the inflammatory response plays a key role in stroke pathobiology. Recently, endovascular treatment (EVT) has revolutionized the management and outcome of patients with AIS due to either extracranial carotid disease or intracranial disease. The neutrophil-to-lymphocyte ratio (NLR) represents an easily available inflammatory biomarker. The aim of the study was to assess the relationship between the NLR at admission and the occurrence of early neurological deterioration (END) in patients with AIS who underwent EVT. Patients with AIS and proximal arterial occlusion in the anterior circulation undergoing EVT were retrospectively identified. Absolute neutrophil count (ANC) and absolute lymphocyte count (ALC) were collected from admission blood work to calculate the NLR. The study outcome was END defined as an increase in at least 4 points in NIHSS score or death between baseline and 24 h after the ischemic event. Patients included were 211, and END occurred in 30 (14.2%). Patients with older age (OR = 1.07, 95% CI: 1.02−1.13), higher serum glucose (OR = 1.01, 95% CI: 1.01−1.02), and higher NLR (OR = 1.011, 95% CI: 1.04−1.18) had an increased risk of END. The best predictive cut-off value of NLR was 6.4, and END occurred in 24.1% and 3.9% of the patients with NLR ≥ 6.4 and <6.4, respectively (p < 0.001). In patients with AIS undergoing EVT, higher NLR values predicted a higher risk of END. Biomarkers able to identify inflammatory mechanisms might identify novel treatment targets and enhance proof-of-concept trials of immunomodulation in stroke.

Utility of P-wave abnormalities for distinguishing embolic stroke from non-embolic stroke

BACKGROUND

Our aim was to analyze the incidence of P-wave abnormalities in embolic and non-embolic strokes, and evaluate its clinical usefulness for predicting stroke etiology.

METHODS

We included 376 consecutive patients hospitalized for acute ischemic stroke from January 2015 to September 2021. Among the patients in sinus rhythm at admission, 31 had ischemic stroke due to atrial fibrillation (AF)-related embolism, 59 had embolic stroke of unknown source (ESUS), and 143 had non-embolic stroke. P-wave abnormalities were defined as 1. P-wave axis abnormality (PWAA); 2. P-wave terminal force in V₁ (PTFV1) ≤ -4000 μV*ms; 3. advanced inter-atrial block (A-IAB).

RESULTS

The prevalence of each type of abnormality was consistently lower in patients with non-embolic stroke than in those with AF-related embolism (AF-related vs. ESUS vs. non-embolic; PWAA, 45% vs. 20% vs. 14%; PTFV1, 36% vs. 37% vs. 15%; and A-IAB, 55% vs. 31% vs. 13%, respectively). The identification of at least one type of P-wave abnormality improved the sensitivity compared to using a single abnormality parameter (sensitivity 72%, specificity 62%), while at least two types of abnormality had low sensitivity, but high specificity (sensitivity 29%, specificity 95%). Multivariate regression analysis revealed that identification of at least one type of P-wave abnormality was independently associated with embolic stroke (odds ratio 3.11, 95%CI 1.46-6.63).

CONCLUSIONS

The incidence of each type of P-wave abnormality was significantly lower in patients with non-embolic stroke. A combination of PWAA, PTFV1, and A-IAB parameters could be useful for distinguishing embolic from non-embolic stroke.

Review and update of the concept of embolic stroke of undetermined source

Ischaemic strokes have traditionally been classified according to the TOAST criteria, in which strokes with unclear aetiology are classified as cryptogenic strokes. However, the definition of cryptogenic stroke did not meet the operational criteria necessary to define patient populations for randomized treatment trials. To address this problem, the concept of embolic stroke of undetermined source (ESUS) was developed and published in 2014. A hypothesis that underpinned this concept was that most strokes in patients with ESUS are caused by embolic events, perhaps many cardioembolic, and that anticoagulation would prevent secondary ischaemic events. On this basis, two large randomized trials were conducted to compare the non-vitamin K antagonist oral anticoagulants (NOACs) dabigatran and rivaroxaban with aspirin. Neither NOAC was superior to aspirin in these trials, although subgroups of patients with ESUS seemed to benefit specifically from anticoagulation or antiplatelet therapy. The neutral results of the trials of anticoagulation and insights into ESUS from research conducted since the concept was introduced warrant reassessment of the ESUS construct as a research concept and a treatment target. In this Review, we discuss the evidence produced since the concept of ESUS was introduced, and propose updates to the criteria and diagnostic algorithm in light of the latest knowledge.

Prevalence of markers of atrial cardiomyopathy in embolic stroke of undetermined source: A systematic review

BACKGROUND

Emerging evidence suggests the potential role of atrial cardiomyopathy (AC) as a direct thromboembolic determinant in embolic stroke of undetermined source (ESUS).

OBJECTIVE

We aimed to quantify the prevalence of potential AC markers among ESUS, non-cardioembolic (NCE) and cardioembolic (CE) stroke patients.

METHODS

PubMed and the Cochrane Central Register of Controlled Trials (CENTRAL) were searched for publications from inception to October 2021, with duplicate data extraction and risk of bias assessment. The Newcastle-Ottawa assessment scale was used to evaluate study quality.

RESULTS

Among 398 screened studies, 11 observational studies with 2009 ESUS patients (mean age 66.5 years) fulfilled the inclusion criteria. Of electrocardiographic markers, increased P-wave terminal force in lead V1 was more prevalent in ESUS vs NCE (OR=2.26, 95%CI: 1.40-3.66). Of imaging markers, left atrial volume index (LAVI) and left atrial diameter (LAd) were higher in ESUS vs NCE (OR=1.04, 95%CI: 1.02-1.06 and OR=3.41, 95%CI: 1.35-8.61 respectively). Non-chicken wing morphology of the left atrial appendage was more frequent in ESUS compared to NCE patients in the majority of studies. Of serum biomarkers, the prevalence of NT-proBNP >250 pg/ml did not differ among ESUS vs NCE (OR=0.73, 95%CI: 0.39 -1.35).

CONCLUSIONS

Electrocardiographic, echocardiographic markers and advanced imaging modalities able to assess the morphologic characteristics of left atrial appendage and left atrial function may be important tools to discriminate AC among ESUS vs NCE stroke patients. Prospective studies exploring the association of potential AC markers with ESUS occurrence are warranted to validate their clinical utility.

A critical assessment of the current pharmacotherapy for the treatment of embolic strokes of undetermined source

INTRODUCTION

"Embolic stroke of undetermined source" (ESUS) is a term coined to identify non-lacunar stroke whose mechanism is likely to be embolic, and the source remains unidentified. The best antithrombotic treatment for preventing stroke recurrence in this population has not been delineated.

AREAS COVERED

The authors summarize and critically appraise the currently available evidence about the antithrombotic treatment for preventing stroke recurrence in patients with ESUS. Randomized trials addressing this topic were identified through MEDLINE (accessed by PubMed, as of November 2021, week 4).

EXPERT OPINION

Recent randomized trials have failed to demonstrate a significant benefit of direct oral anticoagulants over aspirin in reducing the recurrence of cerebral infarctions in unselected cohorts of patients with ESUS. The heterogeneity and often overlap of embolic sources may be possible explanations for the overall absence of a benefit of oral anticoagulants in ESUS as a single homogeneous entity. The results of these trials and their subgroup analyses have provided important cues to understand the pathophysiology of ESUS. They have, furthermore, increased in the interest in researchers in identifying distinct etiological phenotypes within this stroke population. There is a good rationale for ongoing and future investigations in order to tailor antithrombotic treatment according to individual features of patients with ESUS.

Atrial cardiopathy and non-stenotic intracranial complicated atherosclerotic plaque in patients with embolic stroke of undetermined source

OBJECTIVE

To assess (1) the association between atrial cardiopathy (AC) and non-stenotic intracranial complicated atherosclerotic plaque (NICAP) in patients with embolic stroke of undetermined source (ESUS) or small-vessel disease (SVD), and (2) the performance of previously proposed biomarkers to identify AC as the underlying aetiology in ESUS.

METHODS

Based on our high-resolution MRI (HR-MRI) cohort, 403 subjects (243 ESUS and 160 SVD) were enrolled in the final analysis. All patients underwent intracranial HR-MRI to assess the presence of ipsilateral NICAP. Biomarkers of AC (ie, P-wave terminal force in lead V1 (PTFV1) on ECG, N-terminal probrain natriuretic peptide (NT-proBNP), high-sensitivity cardiac troponin T and left atrial diameter) were collected within 24 hours after admission.

RESULTS

Among patients without ipsilateral NICAP, we found an association between the presence of AC (adjusted OR (aOR): 4.76, 95% CI 2.48 to 9.14), increased PTFV1 (aOR: 5.70, 95% CI: 2.43 to 13.39) and NT-proBNP (aOR: 1.65, 95% CI: 1.16 to 2.35) with ESUS. This association was not evident among patients with ipsilateral NICAP. The discrimination between ESUS versus SVD by AC/AC-related biomarkers was significantly improved after excluding ipsilateral NICAP. Similarly, the discrimination between ESUS and SVD by ipsilateral NICAP was notably augmented after excluding AC, PTFV1 and NT-proBNP.

INTERPRETATION

AC is more prevalent in patients who had ESUS without ipsilateral NICAP compared with patients with, implying that AC and ipsilateral NICAP are two distinct, competing aetiologies of ESUS. Among the AC biomarkers studied in this analysis, PTFV1 seems to be the most informative.

Age Alters Prevalence of Left Atrial Enlargement and Nonstenotic Carotid Plaque in Embolic Stroke of Undetermined Source

BACKGROUND

Nonstenotic carotid plaque and undetected atrial fibrillation are potential mechanisms of embolic stroke of undetermined source (ESUS), but it is unclear which is more likely to be the contributing stroke mechanism. We explored the relationship between left atrial enlargement (LAE) and nonstenotic carotid plaque across age ranges in an ESUS population.

METHODS

A retrospective multicenter cohort of consecutive patients with unilateral, anterior circulation ESUS was queried (2015 to 2021). LAE and plaque thickness were determined by transthoracic echocardiography and computed tomography angiography, respectively. Descriptive statistics were used to compare plaque features in relation to age and left atrial dimensions.

RESULTS

Among the 4155 patients screened, 273 (7%) met the inclusion criteria. The median age was 65 years (interquartile range [IQR] 54-74), 133 (48.7%) were female, and the median left atrial diameter was 3.5 cm (IQR 3.1-4.1). Patients with any LAE more frequently had hypertension (85.9% versus 67.2%, P<0.01), diabetes (41.0% versus 25.6%, P=0.01), dyslipidemia (56.4% versus 40.0%, P=0.01), and coronary artery disease (22.8% versus 11.3%, P=0.02). Carotid plaque thickness was greater ipsilateral versus contralateral to the stroke hemisphere in the overall cohort (median 1.9 mm [IQR 0-3] versus 1.5 mm [IQR 0-2.6], P<0.01); however, this was largely driven by the subgroup of patients without any LAE (median 1.8 mm [IQR 0-2.9] versus 1.5 mm [IQR 0-2.5], P<0.01). Compared with patients ≥70 years, younger patients had more carotid plaque ipsilateral versus contralateral (mean difference 0.42 mm±1.24 versus 0.08 mm±1.54, P=0.047) and less moderate-to-severe LAE (6.3% versus 15.3%, P=0.02).

CONCLUSIONS

Younger patients with ESUS had greater prevalence of ipsilateral nonstenotic plaque, while the elderly had more LAE. The differential effect of age on the probability of specific mechanisms underlying ESUS should be considered in future studies.

The Relationship Between Atrial Cardiopathy Biomarkers and Prognosis of Patients With Embolic Stroke of Undetermined Source

Objective

To compare the proportion of atrial cardiopathy in patients with embolic stroke of undetermined source (ESUS) and other non-cardiac strokes, and to evaluate the prognostic value of atrial cardiopathy biomarkers in patients with ESUS.

Methods

This retrospective study enrolled patients with ischemic stroke from January 2018 to April 2020 in a single stroke center, and compared the proportion of atrial cardiopathy in (1) ESUS group, (2) large artery atherosclerosis (LAA) group, and (3) small-vessel occlusion (SVO) group. Then, it compared the baseline characteristics between ESUS patients with atrial cardiopathy and cardioembolism (CE) group. In addition, the relationship was compared between the biomarkers of atrial cardiopathy and prognosis in patients with ESUS.

Results

In total, 316 patients with ischemic stroke were included that included 105 (33.23%) ESUS, 84 (26.58%) LAA, 73 (23.10%) SVO, and 54 (17.09%) CE. Among these patients, patients with ESUS were younger, and had lower triglyceride, lower low-density lipoprotein than non-ESUS group. The proportion of atrial cardiopathy in ESUS group was higher than LAA group or SVO group (42.86 vs. 17.86 vs. 8.22%, p < 0.001). Compared with non-atrial cardiopathy group, patients with atrial cardiopathy were older, had lower EF value, larger left ventricular diameter, and longer PR interval. Among 105 patients with ESUS, 11 (10.78%) cases died, 32 (31.37%) cases had poor functional outcome (mRS >2). In the multivariable model, the risk factor associated with the death risk of patients with ESUS was N-terminal pro-B-type natriuretic peptide (NT-proBNP) >250 pg/ml [p = 0.025, hazard ratio (HR) = 4.626, 95% CI: 1.212–17.652] after a 1-year follow-up.

Conclusions

Atrial cardiopathy is more common in patients with ESUS, and the characteristics of ESUS patients with atrial cardiopathy are similar to those in patients with CE. NT-proBNP >250 pg/ml is related to the risk of death in patients with ESUS.

Association Between Carotid Artery Perivascular Fat Density and Embolic Stroke of Undetermined Source

Aim

This study aims to retrospectively evaluate the association between pericarotid inflammation and the presence of embolic stroke of undetermined source (ESUS).

Methods

In total, 126 patients with ESUS and 118 patients with ischemic stroke from large artery atherosclerosis (LAA) were enrolled. All the patients underwent brain MRI and a neck CT angiography (CTA) examination. Reviewers were blinded to infarct location and stroke cause. Paired t-tests assessed within-subjects differences in mean Hounsfield units (HUs) in carotid perivascular fat between the cerebral infarction side and contralateral side for ESUS and LAA ischemic stroke cases. The unpaired Student's t-test was used to assess between-subjects differences in mean HUs between ESUS and LAA ischemic stroke cases.

Results

In both the ESUS cases and LAA ischemic stroke cases, the pericarotid fat density around the carotid artery ipsilateral to the stroke significantly increased compared with contralateral stroke position in both the groups (ESUS cases −56.31 ± 18.70 vs. −67.31 ± 20.01, p = 0.000; LAA ischemic stroke cases −51.62 ± 19.95 vs. −64.58 ± 22.68, p = 0.000). However, there was no significant difference in ipsilateral and contralateral positions to infarct between ESUS cases and LAA ischemic stroke cases (ipsilateral to infarct −56.31 ± 18.70 vs. −51.62 ± 19.95, p = 0.059; contralateral to infarct −67.31 ± 20.01 vs. −64.58 ± 22.68, p = 0.320).

Conclusion

We found increased density in the fat surrounding carotid artery ipsilateral to stroke compared with contralateral in ESUS, suggesting the presence of an inflammatory reaction that extends beyond the vessel lumen in patients with ESUS with a risk factor profile similar to LAA strokes.

The Association Between Standard Electrocardiography and Cerebral Small Vessel Disease in a Memory Clinic Study

BACKGROUND

P-wave terminal force in lead V1 (PTFV1) on electrocardiography has been associated with atrial fibrillation and ischemic stroke.

OBJECTIVE

To investigate whether PTFV1 is associated with cerebral small vessel disease (CSVD) markers and etiological subtypes of cognitive impairment and dementia.

METHODS

Participants were recruited from ongoing memory clinic study between August 2010 to January 2019. All participants underwent physical and medical evaluation along with an electrocardiography and 3 T brain magnetic resonance imaging. Participants were classified as no cognitive impairment, cognitive impairment no dementia, vascular cognitive impairment no dementia, and dementia subtypes (Alzheimer's disease and vascular dementia). Elevated PTFV1 was defined as >  4,000μV×ms and measured manually on ECG.

RESULTS

Of 408 participants, 78 (19.1%) had elevated PTFV1 (37 women [47%]; mean [SD] age, 73.8 [7.2] years). The participants with elevated PTFV1 had higher burden of lacunes, cerebral microbleeds (CMB), and cortical microinfarcts. As for the CMB location, persons with strictly deep CMB and mixed CMB had significantly higher PTFV1 than those with no CMB (p = 0.005, p = 0.007). Regardless of adjustment for cardiovascular risk factors and/or heart diseases, elevated PTFV1 was significantly associated with presence of CMB (odds ratio, 2.26; 95% CI,1.33-3.91).

CONCLUSION

Elevated PTFV1 was associated with CSVD, especially deep CMB. PTFV1 in vascular dementia was also higher compared to Alzheimer's disease. Thus, PTFV1 might be a potential surrogate marker of brain-heart connection and vascular brain damage.

How Old is Too Old? Closure of Patent Foramen Ovale in Older Patients

Percutaneous closure of a patent foramen ovale (PFO) reduces the risk of recurrent cryptogenic stroke specifically in younger patients. The three randomized controlled trials that led to the widespread adoption of PFO closure excluded patients over the age of 60 years. Older patients frequently have other cardiac and vascular conditions that are common risk factors for stroke, whereas paradoxical embolism through a PFO is relatively rare. Younger patients theoretically benefit the most from closure due to longer lifetime exposure risk and absence of other traditional risk factors. PFO in older patients with cryptogenic strokes is often encountered in clinical practice, making up an increasing number of cardiology referrals, yet cardiologists lack guidelines and evaluation tools for these patients. This review explores the history of PFO closure – emphasizing data in older adults – and discusses the evaluation and treatment of older people with cryptogenic stroke and PFO while further trials in this important population are awaited.

Systemic Inflammatory Response Index and Futile Recanalization in Patients with Ischemic Stroke Undergoing Endovascular Treatment

Futile recanalization remains a significant challenge for endovascular treatment (EVT) of acute ischemic stroke (AIS). The inflammatory response that occurs after cerebral infarct plays a central role in stroke pathobiology that can influence the outcome of a recanalization procedure. The aim of this study was to evaluate the relationship between the systemic inflammatory response index (SIRI) and futile recanalization in patients with AIS. We retrospectively identified consecutive patients with ischemic stroke due to proximal arterial occlusion in the anterior circulation, who were treated with EVT and achieved near-complete or complete recanalization. Absolute neutrophil count (ANC), absolute monocyte count (AMC), and absolute lymphocyte count (ALC) were collected from admission blood work to calculate SIRI as ANC × AMC/ALC. The study outcome was futile recanalization, defined as poor functional status [modified Rankin scale (mRS) score ≥ 3] at 3 months despite complete or near-complete recanalization. A total of 184 patients were included. Futile recanalization was observed in 110 (59.8%) patients. Older patients (odds ratio (OR) = 1.07, 95% confidence interval (CI): 1.04–1.10, p < 0.001), higher admission National Institutes of Health stroke scale score (OR = 1.10, 95% CI: 1.02–1.19, p = 0.013), and higher admission SIRI (OR = 1.08, 95% CI: 1.01–1.17, p = 0.028) increased the risk of the poor outcome at 3 months despite complete or near-complete recanalization.

Promising Biomarker Candidates for Cardioembolic Stroke Etiology. A Brief Narrative Review and Current Opinion

Determining the cause of stroke is considered one of the main objectives in evaluating a stroke patient in clinical practice. However, ischemic stroke is a heterogeneous disorder and numerous underlying disorders are implicated in its pathogenesis. Although progress has been made in identifying individual stroke etiology, in many cases underlying mechanisms still remain elusive. Since secondary prevention strategies are tailored toward individual stroke mechanisms, patients whose stroke etiology is unknown may not receive optimal preventive treatment. Cardioembolic stroke is commonly defined as cerebral vessel occlusion by distant embolization arising from thrombus formation in the heart. It accounts for the main proportion of ischemic strokes, and its share to stroke etiology is likely to rise even further in future decades. However, it can be challenging to distinguish cardioembolism from other possible etiologies. As personalized medicine advances, stroke researchers' focus is increasingly drawn to etiology-associated biomarkers. They can provide deeper insight regarding specific stroke mechanisms and can help to unravel previously undetected pathologies. Furthermore, etiology-associated biomarkers could play an important role in guiding future stroke prevention strategies. To achieve this, broad validation of promising candidate biomarkers as well as their implementation in well-designed randomized clinical trials is necessary. This review focuses on the most-promising candidates for diagnosis of cardioembolic stroke. It discusses existing evidence for possible clinical applications of these biomarkers, addresses current challenges, and outlines future perspectives.

Endovascular treatment and cognitive outcome after anterior circulation ischemic stroke

The impact of reperfusion therapies on cognition has been poorly explored and little knowledge exists. We explored the influence of endovascular treatment (EVT) on cognitive outcome in patients with anterior circulation ischemic stroke. Patients presenting with ischemic stroke due to anterior large vessel occlusion who underwent intravenous thrombolysis (IVT) alone or EVT plus IVT were recruited. Cognitive abilities were evaluated at 6 months from stroke through a neuropsychological test battery. A total of 88 patients with a mean age of 66.3 ± 12.9 years were included, of which 38 treated with IVT alone and 50 with IVT plus EVT. Compared to patients treated with IVT alone, patients who received EVT plus IVT performed significantly better at the neuropsychological tests exploring executive functions, attention, abstract reasoning, visuospatial ability, visual and verbal and memory. At multivariable regression analysis, the EVT was independently associated with the 6-month cognitive performance after the adjustment for age, sex, admission National Institutes of Health Stroke Scale score, systolic blood pressure, glucose level, Alberta Stroke Program Early CT score, side of stroke, site of occlusion, and Back Depression Inventory score [Stroop Test Word Reading: _adjβ = 13.99, 95% confidence interval (CI) 8.47–19.50, p < 0.001; Stroop Test Colour Naming: _adjβ = 6.63, 95% CI 2.46–10.81, p = 0.002; Trail Making Test-A: _adjβ = − 92.98, 95% CI − 153.76 to − 32.20, p = 0.003; Trail Making Test-B: _adjβ = − 181.12, 95% CI − 266.09 to − 96.15; p < 0.001; Digit Span Test Forward: _adjβ = 1.44, 95% CI 0.77–2.10, p < 0.001; Digit Span Test Backward: _adjβ = 1.10, 95% CI 0.42–1.77, p = 0.002; Coloured Progressive Matrices: _adjβ = 5.82, 95% CI 2.71–8.93, p < 0.001; Rey Complex Figure Test-Copy: _adjβ = 6.02, 95% CI 2.74–9.30, p < 0.001; Rey Complex Figure Test-Immediate recall: _adjβ = 6.00, 95% CI 2.34–9.66, p = 0.002; Rey Complex Figure Test-Delayed recall: _adjβ = 5.73, 95% CI 1.95–9.51, p = 0.003; Rey Auditory Verbal Learning Test-Immediate recall: _adjβ = 12.60, 95% CI 6.69–18.52, p < 0.001; Rey Auditory Verbal Learning Test-Delayed recall: _adjβ = 1.85, 95% CI 0.24–3.45, p = 0.025]. Patients treated with EVT plus IVT had better cognitive performance than patients treated with IVT alone at 6 months from anterior circulation ischemic stroke.

Identification of Co-expressed Genes Between Atrial Fibrillation and Stroke

Atrial fibrillation (AF) increases the risk of ischemic stroke and systemic arterial embolism. However, the risk factors or predictors of stroke in AF patients have not been clarified. Therefore, it is necessary to find effective diagnostic and therapeutic targets. Two datasets were downloaded from the Gene Expression Omnibus (GEO) database. Differently expressed genes (DEGs) were identified between samples of atrial fibrillation without stroke and atrial fibrillation with stroke. Enrichment analysis of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) by Gene Set Enrichment Analysis (GSEA), construction and analysis of protein-protein interaction (PPI) network and significant module, and the receiver operator characteristic (ROC) curve analysis were performed. A total of 524 DEGs were common to both datasets. Analysis of KEGG pathways indicated that the top canonical pathways associated with DEGs were ubiquitin-mediated proteolysis, endocytosis, spliceosome, and so on. Ten hub genes (SMURF2, CDC42, UBE3A, RBBP6, CDC5L, NEDD4L, UBE2D2, UBE2B, UBE2I, and MAPK1) were identified from the PPI network and were significantly associated with a diagnosis of atrial fibrillation and stroke (AFST). In summary, a total of 524 DEGs and 10 hub genes were identified between samples of atrial fibrillation without stroke and atrial fibrillation with stroke. These genes may serve as the target of early diagnosis or treatment of AF complicated by stroke.

Exploring the causal pathway from ischemic stroke to atrial fibrillation: a network Mendelian randomization study

BACKGROUND AND PURPOSE

Previous studies have found ischemic stroke is associated with atrial fibrillation. However, the causal association between ischemic stroke and atrial fibrillation is not clear. Furthermore, the network relationship among ischemic stroke, atrial fibrillation and its risk factors need further attention. This study aims to examine the potential causal association between ischemic stroke and atrial fibrillation and further to explore potential mediators in the causal pathway from ischemic stroke to atrial fibrillation.

METHODS

Summary statistics from the ISGC (case = 10,307 and control = 19,326) were used as ischemic stroke genetic instruments, AFGen Consortium data (case = 65,446 and control = 522,744) were used for atrial fibrillation, and other consortia data were used for potential mediators (fasting insulin, white blood cell count, procalcitonin, systolic and diastolic blood pressure, body mass index, waist circumference, and height). Under the framework of network Mendelian randomization, two-sample Mendelian randomization study was performed using summary statistics from several genome-wide association studies. Inverse-variance weighted method was performed to estimate causal effect.

RESULTS

Blood pressure mediates the causal pathways from ischemic stroke to atrial fibrillation. The total odds ratio of ischemic stroke on atrial fibrillation was 1.05 (95% confidence interval [CI], 1.02 to 1.07; P = 1.3 × 10-5). One-unit increase of genetically determined ischemic stroke was associated with 0.02 (DBP: 95% CI, 0.001 to 0.034, P = 0.029; SBP: 95% CI, 0.006 to 0.034, P = 0.003) upper systolic and diastolic blood pressure levels. Higher genetically determined systolic and diastolic blood pressure levels were associated with higher atrial fibrillation risk (DBP: RR, 1.18; 95% CI, 1.03 to 1.35; P = 0.012. SBP: RR, 1.18; 95% CI, 1.01 to 1.38; P = 0.04). Specially, we also found the bidirectional causality between blood pressure and ischemic stroke.

CONCLUSIONS

Our study provided a strong evidence that raised blood pressure in stroke patients increases the risk of atrial fibrillation and active acute blood pressure lowering can improve the outcome in ischemic stroke patients.

Atrial cardiopathy in patients with embolic strokes of unknown source and other stroke etiologies

Objective

To investigate the prevalence and clinical determinants of atrial cardiopathy in patients with embolic stroke of unknown source (ESUS) and compare with other established stroke etiologies.

Methods

In a cross-sectional study of 846 consecutive patients with ischemic stroke, we compared the prevalence of atrial cardiopathy (defined by p-wave terminal force in V1 >5,000 µV·ms or severe left atrial enlargement) between ESUS patients and patients with large artery atherosclerosis (LAA) and small vessel disease (SVD) strokes. Baseline characteristics were also compared between ESUS and cardioembolic (CE) patients.

Results

Of all, 158 (19%) patients met ESUS diagnostic criteria, while others were classified into LAA (n = 224, 26%), SVD (n = 154, 18%), and CE (n = 310, 37%). The prevalence of atrial cardiopathy was higher in ESUS patients compared to noncardioembolic stroke patients (26.6% vs 12.1% in LAA vs 16.9% in SVD; p = 0.001). ESUS patients were younger, were less hypertensive, and had higher cholesterol and low-density lipoprotein levels, but also had less left ventricular or atrial abnormalities when compared to CE patients.

Conclusion

The prevalence of atrial cardiopathy was high in ESUS patients compared with patients with nonembolic strokes. Interestingly, ESUS patients were also clinically different from CE patients. While the presence of atrial cardiopathy may reflect a unique mechanism of thromboembolism in ESUS patients, it is still unclear if they may benefit from anticoagulation, or if the presence of atrial cardiopathy in this population could serve as a risk-stratifying marker for stroke recurrence. Further efforts are necessary to provide better characterization of the ESUS population in order to develop better stroke preventive strategies.

Electrocardiographic left atrial abnormality and silent vascular brain injury: The Northern Manhattan Study

Hypothesis

We hypothesized that P wave terminal Force in the V1 lead (PTFV₁) would be associated with leukoaraiosis and subclinical infarcts, especially cortical infarcts, in a population-based, multi-ethnic cohort.

Methods

PTFV₁ was collected manually from baseline electrocardiograms of clinically stroke-free Northern Manhattan Study participants. Investigators read brain MRIs for superficial infarcts, deep infarcts, and white matter hyperintensity volume (WMHV). WMHV was adjusted for head size and log transformed, achieving a normal distribution. Logistic regression models investigated the association of PTFV₁ with cortical and with all subclinical infarcts. Linear regression models examined logWMHV. Models were adjusted for demographics and risk factors.

Results

Among 1174 participants with PTFV₁ measurements, the mean age at MRI was 70 ± 9 years. Participants were 14.4% white, 17.6% black, and 65.8% Hispanic. Mean PTFV₁ was 3587.35 ± 2315.62 μV-ms. Of the 170 subclinical infarcts, 40 were cortical. PTFV₁ ≥ 5000 μV-ms was associated with WMHV in a fully adjusted model (mean difference in logWMHV 0.15, 95% confidence interval 0.01–0.28). PTFV₁ exhibited a trend toward an association with cortical infarcts (unadjusted OR per SD change logPTFV₁ 1.30, 95% CI 0.94–1.81), but not with all subclinical infarcts.

Conclusion

Electrocardiographic evidence of left atrial abnormality was associated with leukoaraiosis.

Atrial Cardiopathy and Sympatho-Vagal Imbalance in Cryptogenic Stroke: Pathogenic Mechanisms and Effects on Electrocardiographic Markers

Recently, atrial cardiopathy has emerged as possible pathogenic mechanism in cryptogenic stroke and many electrocardiographic (ECG) markers have been proposed in order to detect an altered atrial substrate at an early stage. The autonomic nervous system (ANS) plays a well-known role in determining significant and heterogeneous electrophysiological changes of atrial cardiomyocytes, that promote atrial fibrillation episodes in cardioembolic stroke. Conversely, the role of ANS in atrial cardiopathy and cryptogenic stroke is less known, as well as ANS effects on ECG markers of atrial dysfunction. In this paper, we review the evidence linking ANS dysfunction and atrial cardiopathy as a possible pathogenic factor in cryptogenic stroke.

Embolic strokes of undetermined source in a cohort of Polish stroke patients

We aimed to provide a descriptive analysis of embolic stroke of undetermined etiology (ESUS) population based on a long-term prospective stroke registry. We retrospectively analyzed data collected in a detailed registry regarding consecutive patients admitted for first-ever ischemic stroke (IS) between January 2001 and December 2015. We used Org 10172 in Acute Stroke Treatment classification supplemented with ESUS criteria proposed by the Cryptogenic Stroke/ESUS International Working Group. Within the ESUS group, we additionally compared patients ≤ 60 and > 60 years of age. During the study period, there was a total of 3008 (1615 females and 1393 males) admissions of first-ever strokes. The most frequent cause was undetermined (38.7%), followed by cardioembolic (27.7%), large artery atherosclerosis (18.2%), small vessel disease (11.9%), and other determined (3.6%). We identified 326 patients as ESUS, which accounted for 10.8% of all strokes and 28% of strokes of undetermined etiology. ESUS patients were the youngest. Compared to all types of stroke but for those with small vessel disease, ESUS patients were most often independent before stroke and had the least severe neurological deficit at admission and the best outcome at discharge. ESUS patients ≤ 60 years were more frequently independent at discharge than ESUS patients > 60 years. Approximately 11% of patients from our registry met ESUS criteria. ESUS patients were younger when compared to all other stroke etiologies, suffered less severe strokes, and had more favorable outcome at discharge than other groups except for those with small vessel disease strokes.

Patent Foramen Ovale and Cryptogenic Stroke or Transient Ischemic Attack: To Close or Not to Close? A Systematic Review and Meta-Analysis

BACKGROUND

The optimal strategy of secondary stroke prevention in patients with patent foramen ovale (PFO) is controversial. This study was performed to evaluate the efficacy and safety of the device closure (DC) versus the medical therapy (MT) in patients with cryptogenic stroke or transient ischemic attack (TIA) and PFO.

SUMMARY

Randomized controlled trials with active and control groups receiving the DC plus MT and MT alone in patients with history of cryptogenic stroke/TIA and diagnosis of PFO were systematically searched. The main efficacy outcome was stroke recurrence. Subgroup-analyses were performed according to age, shunt size, and presence of atrial septal aneurysm (ASA). Safety endpoints included any serious adverse event (SAE), atrial fibrillation (AF), and major bleeding complications. Risk ratios (RRs) and hazard ratios (HRs) with 95% CIs were estimated. Five trials were included, involving 3,440 participants (DC = 1,829, MT = 1,611). There was a protective effect of closure in the risk of recurrent stroke (RR 0.43 [0.21-0.90]; p = 0.024; HR = 0.39 [0.19-0.83]; p = 0.014). The benefit of PFO closure was significant in patients with PFO associated with substantial right-to-left shunt or ASA. There were no differences in the risks of SAEs and major bleedings between the groups. The rate of new-onset AF was higher in the DC than in the MT arm (RR 4.46 [2.35-8.41]; p < 0.001). Successful device implantation and effective PFO closure were achieved in 96 and 91% of the patients respectively. Key Messages: In selected adult patients with PFO and history of cryptogenic stroke, the DC plus MT is more effective to prevent stroke recurrence and is associated with an increased risk of new-onset AF compared to the MT alone.