Atrial Cardiopathy and the Risk of Ischemic Stroke in the CHS (Cardiovascular Health Study)

Association between P-wave terminal force in lead V1 and extent of left atrial low-voltage substrate in older patients with paroxysmal atrial fibrillation

BACKGROUND

The P-wave terminal force in lead V1 (PTFV1) is a marker of cardiomyopathy and risk of atrial fibrillation (AF). Low-voltage area (LVA) in the left atrium (LA), which indicates underlying atrial fibrosis, could predict AF recurrence. This study aimed to investigate the correlation between PTFV1 and LVA in older patients with paroxysmal AF.

METHODS

From May 1, 2020, to October 31, 2021, a total of 162 patients aged 65-80 years with paroxysmal AF who underwent index ablation procedures were enrolled. PTFV1 was measured in sinus rhythm (SR) using 12-lead electrocardiograms prior to the ablation. Abnormal PTFV1 was defined as a ≥ 4 mVms depression. Additional LVA ablation beyond circumferential pulmonary vein isolation (CPVI) was performed if LVAs were found.

RESULTS

Among the 162 patients, 88 had a normal PTFV1 and 74 had an abnormal PTFV1 prior to ablation. There was a significant difference in LVA in patients with and without an abnormal PTFV1 (LVA, 11.0 vs. 5.1 cm2, P < 0.001; LVA burden, 8.9% vs. 4.5%, P < 0.001). PTFV1 and PTAV1 were highest in the upper tertile with extensive LVAs (P < 0.001). Multivariate analysis revealed that abnormal PTFV1 was an independent predictor of LVAs (β = 4.961; 95% CI, 2.135-7.788; P < 0.001). After a median follow-up of 23 months, the AF-free survival rate was similar between the normal PTFV1 group and the abnormal PTFV1 group (13/88 vs. 12/74, hazard ratio [HR], 0.933 [95% CI, 0.425-2.047]; P = 0.861).

CONCLUSIONS

Abnormal PTFV1 at baseline was independently associated with the extent of LVA in older patients with paroxysmal AF.

Novel stroke prevention strategies following catheter ablation for atrial fibrillation

Stroke prevention following successful catheter ablation of atrial fibrillation remains a controversial topic. Oral anticoagulation is associated with a significant reduction in stroke risk in the general atrial fibrillation population but may be associated with an increased risk of major bleeding, and the benefit: risk ratio must be considered. Improvement in successful catheter ablation and widespread use of cardiac monitoring devices may allow for novel anticoagulation strategies in a subset of patients with atrial fibrillation, which may optimize stroke prevention while minimizing bleeding risk. In this review, we discuss stroke risk in atrial fibrillation and the effects of successful catheter ablation on thromboembolic risk. We also explore novel strategies for stroke prevention following successful catheter ablation.

Association between atrial cardiopathy and stroke severity in acute ischemic stroke

In this hospital-based cross-sectional analytic study, we retrospectively reviewed clinical data of patients with acute ischemic stroke (AIS) between January 2017 and April 2023. Atrial cardiopathy was defined as any presence of the following: left atrial diameter ≥ 52 mm (males) or ≥ 47 mm (females), elevated P-wave terminal force in V1 > 5000 μV ms, or serum N terminal pro B type natriuretic peptide > 250 pg/ml. Initial stroke severity was defined by the National Institutes of Health Stroke Scale (NIHSS; moderate-to-severe, ≥ 5; and severe, ≥ 15). Univariate and multivariate binary logistic regression analyses were performed to assess the association between atrial cardiopathy and stroke severity. Among 662 AIS patients (mean age 70 years [interquartile range 61-78], 31.3% women), 303 (45.8%) had atrial cardiopathy. Multivariable logistic regression analysis showed that the presence of atrial cardiopathy was significantly associated with a higher odd of moderate-to-severe stroke (adjusted odds ratio [OR] 2.16, 95% confidence interval [CI] 1.46-3.20, p < 0.001) and severe stroke (adjusted OR 4.89, 95%CI 2.45-9.76, p < 0.001). This association remained significant in a sensitivity analysis excluding those with atrial fibrillation or coronary artery disease. Findings of the current study revealed that the association of atrial cardiopathy was with initial stroke severity independent of atrial fibrillation and was even confirmed in patients without atrial fibrillation; future studies to explore improved stroke prevention strategies for patients with atrial cardiopathy are needed.

Atrial Fibrillation, Atrial Myopathy, and Thromboembolism: The Additive Value of Echocardiography and Possible New Horizons for Risk Stratification

Atrial fibrillation (AF) is the most common cardiac sustained arrhythmia, and it is associated with increased stroke and dementia risk. While the established paradigm attributes these complications to blood stasis within the atria and subsequent thrombus formation with cerebral embolization, recent evidence suggests that atrial myopathy (AM) may play a key role. AM is characterized by structural and functional abnormalities of the atria, and can occur with or without AF. Moving beyond classifications based solely on episode duration, the 4S-AF characterization has offered a more comprehensive approach, incorporating patient's stroke risk, symptom severity, AF burden, and substrate assessment (including AM) for tailored treatment decisions. The "ABC" pathway emphasizes anticoagulation, symptom control, and cardiovascular risk modification and emerging evidence suggests broader benefits of early rhythm control strategies, potentially reducing stroke and dementia risk and improving clinical outcomes. However, a better integration of AM assessment into the current framework holds promise for further personalizing AF management and optimizing patient outcomes. This review explores the emerging concept of AM and its potential role as a risk factor for stroke and dementia and in AF patients' management strategies, highlighting the limitations of current risk stratification methods, like the CHA2DS2-VASc score. Echocardiography, particularly left atrial (LA) strain analysis, has shown to be a promising non-invasive tool for AM evaluation and recent studies suggest that LA strain analysis may be a more sensitive risk stratifier for thromboembolic events than AF itself, with some studies showing a stronger association between LA strain and thromboembolic events compared to traditional risk factors. Integrating it into routine clinical practice could improve patient management and targeted therapies for AF and potentially other thromboembolic events. Future studies are needed to explore the efficacy and safety of anticoagulation in AM patients with and without AF and to refine the diagnostic criteria for AM.

The relationship between atrial cardiopathy biomarkers and prognosis of patients with acute ischemic stroke after endovascular treatment

Thromboembolism is a possible consequence of underlying atrial cardiopathy, which can occur even before the onset of atrial fibrillation. Our objective was to examine the association between biomarkers of atrial cardiopathy and outcomes of acute ischemic stroke (AIS) following endovascular treatment (EVT). We conducted a retrospective study that collected data from patients with AIS who underwent EVT and compared the outcomes between those with and without atrial cardiopathy. Neurological function was assessed using the modified Rankin Scale (mRS), with an mRS score >2 indicating poor function at day 90. Additionally, we evaluated secondary consequences, including symptomatic intracerebral hemorrhage (sICH), early neurological deterioration (END), and malignant cerebral edema (MCE). Our study included 87 patients (77.6 ​% male; mean age 60.93 ​± ​12.47 years). Among these patients, 29 (33.3 ​%) had atrial cardiopathy, while the remaining 58 (66.7 ​%) did not. In the atrial cardiopathy group, 12 patients (41.4 ​%) had poor functional outcomes (mRS>2), compared to 19 (32.8 ​%) in the non-atrial cardiopathy group. We observed sICH in 22 (25.3 ​%) patients, END in 14 (16.1 ​%) patients, MCE in 11 (12.6 ​%) patients, and two (2.3 ​%) patients who died in the hospital. We found that patients with PTFV1>5000 ​μV/ms (OR: 8.39, 95 ​% CI: 1.43-105.95, P ​= ​0.02) and NT-proBNP>250 ​pg/mL (OR: 5.09, 95 ​% CI: 1.20-27.63, P ​= ​0.03) had significantly higher risk of END. After adjusting for covariates in the Firth logistic regression, we further found that atrial cardiopathy was significantly associated with END, as revealed by both univariate (OR: 6.31, 95 ​% CI: 1.42-59.87, P ​= ​0.01) and multivariable firth regression models (Modle 1, OR: 7.10, 95 ​% CI: 1.57-67.38, P ​< ​0.01; Modle 2, OR: 7.82, 95 ​% CI: 1.69, 76.36, P ​< ​0.01; Modle 3, OR: 8.59, 95 ​% CI: 1.72-91.70, P ​< ​0.01). Moreover, we observed that atrial cardiopathy was associated with an increased risk of END in AIS patients with large artery atherosclerosis (LAA) receiving EVT. Therefore, clinicians should consider atrial cardiopathy as a possible underlying cause of AIS in their patients. Further investigation is warranted to elucidate the relationship between atrial cardiopathy and AIS's occurrence, progression, and prognosis.

Automated Atrial Fibrillation Diagnosis by Echocardiography without ECG: Accuracy and Applications of a New Deep Learning Approach

BACKGROUND

Automated rhythm detection on echocardiography through artificial intelligence (AI) has yet to be fully realized. We propose an AI model trained to identify atrial fibrillation (AF) using apical 4-chamber (AP4) cines without requiring electrocardiogram (ECG) data.

METHODS

Transthoracic echocardiography studies of consecutive patients ≥ 18 years old at our tertiary care centre were retrospectively reviewed for AF and sinus rhythm. The study was first interpreted by level III-trained echocardiography cardiologists as the gold standard for rhythm diagnosis based on ECG rhythm strip and imaging assessment, which was also verified with a 12-lead ECG around the time of the study. AP4 cines with three cardiac cycles were then extracted from these studies with the rhythm strip and Doppler information removed and introduced to the deep learning model ResNet(2+1)D with an 80:10:10 training-validation-test split ratio.

RESULTS

634 patient studies (1205 cines) were included. After training, the AI model achieved high accuracy on validation for detection of both AF and sinus rhythm (mean F1-score = 0.92; AUROC = 0.95). Performance was consistent on the test dataset (mean F1-score = 0.94, AUROC = 0.98) when using the cardiologist's assessment of the ECG rhythm strip as the gold standard, who had access to the full study and external ECG data, while the AI model did not.

CONCLUSIONS

AF detection by AI on echocardiography without ECG appears accurate when compared to an echocardiography cardiologist's assessment of the ECG rhythm strip as the gold standard. This has potential clinical implications in point-of-care ultrasound and stroke risk stratification.

The usefulness of global longitudinal peak strain and left atrial volume index in predicting atrial fibrillation in patients with ischemic stroke

Introduction

Detection of atrial fibrillation (AF) is crucial for preventing recurrence in patients with ischemic stroke. We aimed to examine whether the left atrial volume index (LAVI) and global longitudinal peak strain (GLPS) are associated with AF in patients with ischemic stroke.

Methods

We prospectively analyzed 678 consecutive patients with ischemic stroke. LAVI and GLPS were assessed using three-dimensional transthoracic echocardiography with speckle-tracking imaging. Multiple logistic regression was used to evaluate the association of AF with LAVI and GLPS. To evaluate the predictive value of LAVI and GLPS for the presence of AF, we used optimism-corrected c-statistics calculated by 100 bootstrap repetitions and the net reclassification improvement (NRI).

Results

The mean patient age was 68 ± 13 years (men, 60%). Patients with AF (18%) were a higher LAVI (41.7 ml/m2 vs. 74.9 ml/m2, P < 0.001) and a higher GLPS than those without AF (-14.0 vs. -17.3, P < 0.001). Among the 89 patients classified with embolic stroke of unknown source, the probable cardioembolic group had higher GLPS (n= 17, -14.6 vs. -18.6, respectively; P= 0.014) than the other groups (n= 72). Adding GLPS to age, hypertension, and the LAVI significantly improved the NRI, with an overall NRI improvement of 6.1% (P= 0.03).

Discussion

The LAVI andGLPS with speckle-tracking imaging echocardiography may help identify patients with AF.

Generalisability of and lessons learned from a mixed-methods study conducted in three low- and middle-income countries to identify care pathways for atrial fibrillation

BACKGROUND

Identifying existing care pathways is the first step for understanding how services can be improved to enable early diagnosis and effective follow-up care for non-communicable diseases (NCDs); however, evidence on how care pathways can and should be identified in low- and middle-income countries (LMICs) is lacking.

OBJECTIVE

To describe generalisability and lessons learned from recruitment and data collection for the quantitative component of a mixed methods study designed to determine the care pathway for atrial fibrillation (AF) in Brazil, China and Sri Lanka.

METHODS

Adults (≥18 years) that spoke the local language and with an AF diagnosis were eligible. We excluded anyone with a hearing or cognitive impairment or ineligible address. Eligible participants were identified using electronic records in Brazil and China; in Sri Lanka, researchers attended the outpatient clinics to identify eligible participants. Data were collected using two quantitative questionnaires administered at least 2-months apart. A minimum sample size of 238 was required for each country.

RESULTS

The required sample size was met in Brazil (n = 267) and China (n = 298), but a large proportion of AF patients could not be contacted (47% and 27%, respectively) or refused to participate (36% and 38%, respectively). In Sri Lanka, recruitment was challenging, resulting in a reduced sample (n = 151). Mean age of participants from Brazil, China and Sri Lanka was 69 (SD = 11.3), 65 (SD = 12.8) and 58 (SD = 11.7), respectively. Females accounted for 49% of the Brazil sample, 62% in China and 70% in Sri Lanka.

CONCLUSIONS

Generalisability was an issue in Brazil and China, as was selection bias. Recruitment bias was highlighted in Sri Lanka. Additional or alternative recruitment methods may be required to ensure generalisability and reduce bias in future studies aimed at identifying NCD care pathways in LMICs.

Markers of Atrial Myopathy in the General Population: Prevalence, Predictors, and Inter-Relations

BACKGROUND

Atrial myopathy refers to structural and functional cardiac abnormalities associated with atrial fibrillation and stroke, but appropriate diagnostic criteria are lacking.

OBJECTIVES

This study aimed to assess prevalence, clinical correlates, and overlap between potential atrial myopathy markers.

METHODS

The population-based SCAPIS (Swedish CArdioPulmonary bioImage Study) prospectively included 6,013 subjects without atrial fibrillation with 24-hour electrocardiograms. Resting electrocardiograms measuring P-wave indices were collected at 1 screening site (n = 1,201), and a random sample (n = 385) had echocardiographic left atrial volume index (LAVi). Atrial myopathy markers were defined as ≥500 premature atrial complexes/24 h, LAVi ≥34 mL/m2, P-wave duration >120 milliseconds, or P-wave terminal force in V1 >4,000 ms·s. Clinical correlates included age, sex, body mass index, height, smoking, physical activity, coronary artery disease, diabetes, systolic blood pressure, antihypertensive medication, and low education.

RESULTS

Atrial myopathy was common; 42% of the sample with all diagnostic modalities available had ≥1 atrial myopathy marker, but only 9% had 2 and 0.3% had ≥3. Only P-wave duration and LAVi were correlated (ρ = 0.10; P = 0.04). Clinical correlates of premature atrial complexes, P-wave indices, and LAVi differed; current smoking (34% increase; P < 0.001), systolic blood pressure (4%/mm Hg increase; P = 0.01), diabetes (35% increase; P = 0.001), and coronary artery disease (71% increase; P = 0.003) were associated with premature atrial complexes, physical activity ≥2 h/wk was associated with increased LAVi (β-coefficient = 3.1; P < 0.0001) and body mass index was associated with P-wave duration (β-coefficient = 0.4/kg/m2; P < 0.0001).

CONCLUSIONS

In the general population, indirect markers of atrial myopathy are common but only weakly correlated, and their risk factor patterns are different. More studies are needed to accurately identify individuals with atrial myopathy with diagnostic methods.

The Role of Electrocardiographic Markers for Predicting Atrial Fibrillation in Patients with Acute Ischemic Stroke: Data from the BIOSIGNAL Cohort Study

BACKGROUND AND AIMS

P-wave abnormalities in the 12-lead electrocardiogram (ECG) have been associated with a higher risk of acute ischemic stroke (AIS) as well as atrial fibrillation (AF). This study aimed to assess pre-determined ECG criteria during sinus rhythm in unselected AIS patients and their value for predicting newly diagnosed atrial fibrillation (NDAF) after hospital admission.

METHODS

P-wave alterations were measured on 12-lead ECG on admission in all consecutively enrolled patients without known AF between October 2014 and 2017. The outcome of interest was NDAF, identified by prolonged electrocardiographic monitoring within one year after the index AIS. Univariable and multivariable logistic regression was applied to assess the magnitude and independence of the association between pre-selected ECG markers and NDAF. The discriminatory accuracy was evaluated with the area under the receiver operating characteristic curve (AUC), and the incremental prognostic value was estimated with the net reclassification index.

RESULTS

NDAF was detected in 87 (10%) of 856 patients during a follow-up of 365 days. Out of the pre-selected ECG parameters, advanced interatrial block (aIAB) and PR interval in lead II were independently associated with NDAF in univariable regression analysis. Only aIAB remained a significant predictor in multivariable analysis. Adding aIAB to the best-performing multivariable regression model improved the discriminatory accuracy to predict NDAF from an AUC of 0.78 (95%-CI 0.77-0.80) to 0.81 (95%-CI 0.80-0.83, p < 0.001).

CONCLUSION

aIAB is independently and highly associated with NDAF in patients with AIS, has high inter-rater reliability, and therefore may be helpful to refine diagnostic work-up to search for AF in AIS.

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.

Atrial Myopathy Quantified by Speckle-tracking Echocardiography in Mice

BACKGROUND

Emerging evidence suggests that atrial myopathy may be the underlying pathophysiology that explains adverse cardiovascular outcomes in heart failure (HF) and atrial fibrillation. Lower left atrial (LA) function (strain) is a key biomarker of atrial myopathy, but murine LA strain has not been described, thus limiting translational investigation. Therefore, the objective of this study was to characterize LA function by speckle-tracking echocardiography in mouse models of atrial myopathy.

METHODS

We used 3 models of atrial myopathy in wild-type male and female C57Bl6/J mice: (1) aged 16 to 17 months, (2) Ang II (angiotensin II) infusion, and (3) high-fat diet+Nω-nitro-L-arginine methyl ester (HF with preserved ejection fraction, HFpEF). LA reservoir, conduit, and contractile strain were measured using speckle-tracking echocardiography from a modified parasternal long-axis window. Left ventricular systolic and diastolic function, and global longitudinal strain were also measured. Transesophageal rapid atrial pacing was used to induce atrial fibrillation.

RESULTS

LA reservoir, conduit, and contractile strain were significantly reduced in aged, Ang II and HFpEF mice compared with young controls. There were no sex-based interactions. Left ventricular diastolic function and global longitudinal strain were lower in aged, Ang II and HFpEF, but left ventricular ejection fraction was unchanged. Atrial fibrillation inducibility was low in young mice (5%), moderately higher in aged mice (20%), and high in Ang II (75%) and HFpEF (83%) mice.

CONCLUSIONS

Using speckle-tracking echocardiography, we observed reduced LA function in established mouse models of atrial myopathy with concurrent atrial fibrillation inducibility, thus providing the field with a timely and clinically relevant platform for understanding the pathophysiology and discovery of novel treatment targets for atrial myopathy.

Atrial Myopathy and Ischemic Stroke in Heart Failure With Preserved Ejection Fraction

Recent studies suggested an association between atrial myopathy and stroke independent of atrial fibrillation (AF). We examined the hypothesis that atrial myopathy may be associated with ischemic stroke in patients with heart failure with preserved ejection fraction. This is an exploratory, post hoc analysis of the Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist (TOPCAT) trial. Patients with sinus rhythm documented at baseline electrocardiogram and without known AF were included in this analysis. Atrial myopathy was defined by echocardiographic evidence of left atrial (LA) enlargement (LA diameter >46 mm or LA volume index >36 ml/m2) or elevated natriuretic peptides (brain natriuretic peptide >100 pg/ml or N-terminal Pro-B-type natriuretic peptide >400 pg/ml). We used Cox regression to investigate the effect of atrial myopathy on incident ischemic stroke over the study period. In 3,445 patients in the TOPCAT trial, 2,225 (mean age 67.5 ± 4.9 years; female 54.8%) had normal sinus rhythm at baseline and no history of AF. Atrial myopathy was present in 756 patients (34.0%). During a median follow-up of 2 years, 56 patients (2.5%) developed ischemic stroke, including 25 with atrial myopathy. Atrial myopathy was associated with increased risk of stroke (hazard ratio = 1.74, 95% confidence interval 1.01 to 2.98, p = 0.04) in multivariate analysis. Diabetes mellitus (hazard ratio = 2.02, 95% confidence interval 1.19 to 3.43 p = 0.01) was the only other independent predictor of stroke. In patients with heart failure with preserved ejection fraction, atrial myopathy increases the risk of ischemic stroke, in the absence of AF. Further investigations are needed to better characterize this association and implement stroke prevention strategies.

Association of Atrial Fibrillation With Stroke and Dementia Accounting for Left Atrial Function and Size

BACKGROUND

Atrial fibrillation (AF) is associated with higher risks of ischemic stroke (IS) and dementia. Whether alterations in left atrial (LA) function or size-atrial myopathy-confound these associations remains unknown.

OBJECTIVES

The purpose of this study was to examine the association of prevalent and incident AF with ischemic stroke and dementia in the ARIC (Atherosclerosis Risk In Communities) study, adjusting for LA function and size.

METHODS

Participants at visit 5 (2011-2013) with echocardiographic LA function (reservoir, conduit, contractile strain, and emptying fraction) and size (maximal, minimal volume index) data, and without prevalent stroke or dementia were followed through 2019. For analysis, we used time-varying Cox regression.

RESULTS

Among 5,458 participants (1,193 with AF, mean age of 76 years) in the stroke analysis and 5,461 participants (1,205 with AF, mean age of 75 years) in the dementia analysis, 209 participants developed ischemic stroke, and 773 developed dementia over 7.1 years (median). In a demographic and risk factor-adjusted model, AF was significantly associated with ischemic stroke (HR, 1.63; 95% CI: 1.11-2.37) and dementia (HR: 1.38, 95% CI: 1.13-1.70). After additionally adjusting for LA reservoir strain, these associations were attenuated and no longer statistically significant (stroke [HR: 1.33, 95% CI: 0.88-2.00], dementia [HR: 1.15, 95% CI: 0.92-1.43]). Associations with ischemic stroke and dementia were also attenuated and not statistically significant after adjustment for LA contractile strain, emptying fraction, and minimal volume index.

CONCLUSIONS

AF-ischemic stroke and AF-dementia associations were not statistically significant after adjusting for measures of atrial myopathy. This proof-of-concept analysis does not support AF as an independent risk factor for ischemic stroke and dementia.

Atrial Cardiopathy: Redefining Stroke Risk Beyond Atrial Fibrillation

Atrial fibrillation (AF) and ischemic stroke are dual epidemics in society, both associated with poor clinical outcomes, patient disability, and significant healthcare expenditure. The conditions are interrelated and share complex causal pathways. Risk stratification algorithms such as the CHADS₂ and CHA₂DS₂-VASc score offer predictive value in stroke and systemic embolism risk in the AF population, however, have limitations. Recent evidence suggests that an intrinsically prothrombotic atrial substrate may precede and promote AF and lead to thromboembolic events independent of the arrhythmia, allowing for a window of intervention before arrhythmia detection and development of ischemic stroke. Initial work has found incremental value in addition of parameters of atrial cardiopathy to traditional stroke risk stratification algorithms, however, requires evaluation with dedicated prospective randomized studies before use in real-world clinical practice. In this narrative review, we explore current evidence and literature on the use of measures of atrial cardiopathy in stroke risk stratification and management.

P-wave terminal force in lead V1 and outcomes in patients with persistent atrial fibrillation undergoing catheter ablation

AIMS

The P-wave terminal force in electrocardiogram lead V1 (PTFV1) correlates with outcomes in patients with paroxysmal atrial fibrillation (AF). Nevertheless, the correlation between the PTFV1 and outcomes after AF ablation in patients with persistent AF remains unclear. This study aimed to determine whether the PTFV1 at 3 months after AF ablation could predict AF recurrence and cardiovascular events in patients with persistent AF.

METHODS

This historical cohort study examined 453 consecutive patients with persistent AF who underwent a first-time AF ablation. We measured the PTFV1 at 3 months after the ablation. An abnormal PTF was defined as a ≥4 mVms depression. The 3-year incidence of AF recurrence and composite cardiovascular events, including strokes, heart failure hospitalizations, and cardiovascular death, were compared between the abnormal and normal PTF groups.

RESULTS

Among 434 enrolled patients, 101 had an abnormal, and 333 normal PTF at 3 months after AF ablation. Compared with the normal PTF group, the abnormal PTF group had a significantly higher incidence of AF recurrence (52.6% vs 28.1%, log-rank P < .001) and cardiovascular events (13.7% vs 2.6%, log-rank P = .005). After adjusting for the risk factors, an abnormal PTF was established as an independent predictor of AF recurrence (hazard ratio [HR] 2.12, 95% confidence interval [CI]: 1.44-3.13, P < .001) and cardiovascular events (HR 3.26, 95% CI: 1.19-8.97, P = .022).

CONCLUSIONS

The PTFV1 at 3 months after AF ablation could be a valuable noninvasive predictor of both AF recurrence and cardiovascular events in patients with persistent AF.

Plasma Proteomic Associations With Incident Ischemic Stroke in Older Adults: The Cardiovascular Health Study

BACKGROUND AND OBJECTIVES

Plasma proteomics may elucidate novel insights into the pathophysiology of ischemic stroke (IS), identify biomarkers of IS risk, and guide development of nascent prevention strategies. We evaluated the relationship between the plasma proteome and IS risk in the population-based Cardiovascular Health Study (CHS).

METHODS

Eligible CHS participants were free of prevalent stroke and underwent quantification of 1,298 plasma proteins using the aptamer-based SOMAScan assay platform from the 1992-1993 study visit. Multivariable Cox proportional hazards regression was used to evaluate associations between a 1-SD increase in the log2-transformed estimated plasma protein concentrations and incident IS, adjusting for demographics, IS risk factors, and estimated glomerular filtration rate. For proteins independently associated with incident IS, a secondary stratified analysis evaluated associations in subgroups defined by sex and race. Exploratory analyses evaluated plasma proteomic associations with cardioembolic and noncardioembolic IS and proteins associated with IS risk in participants with left atrial dysfunction but without atrial fibrillation.

RESULTS

Of 2,983 eligible participants, the mean age was 74.3 (±4.8) years, 61.2% were women, and 15.4% were Black. Over a median follow-up of 12.6 years, 450 participants experienced an incident IS. N-terminal probrain natriuretic peptide (NTproBNP, adjusted HR 1.37, 95% CI 1.23-1.53, p = 2.08 × 10-08) and macrophage metalloelastase (MMP12, adjusted HR 1.30, 95% CI 1.16-1.45, p = 4.55 × 10-06) were independently associated with IS risk. These 2 associations were similar in men and women and in Black and non-Black participants. In exploratory analyses, NTproBNP was independently associated with incident cardioembolic IS, E-selectin with incident noncardioembolic IS, and secreted frizzled-related protein 1 with IS risk in participants with left atrial dysfunction.

DISCUSSION

In a cohort of older adults, NTproBNP and MMP12 were independently associated with IS risk. We identified plasma proteomic determinants of incident cardioembolic and noncardioembolic IS and found a novel protein associated with IS risk in those with left atrial dysfunction.

New pharmacotherapeutic options for oral anticoagulant treatment in atrial fibrillation patients aged 65 and older: factor XIa inhibitors and beyond

INTRODUCTION

Although much progress has been made using anticoagulation for stroke prevention in patients with non-valvular atrial fibrillation, bleeding is still a major concern.

AREAS COVERED

This article reviews current pharmacotherapeutic options in this setting. Particular emphasis is placed on the ability of the new molecules to minimize the bleeding risk in elderly patients. A systematic search of PubMed, Web of Science, and the Cochrane Library up to March 2023 was carried out.

EXPERT OPINION

Contact phase of coagulation is a possible new target for anticoagulant therapy. Indeed, congenital or acquired deficiency of contact phase factors is associated with reduced thrombotic burden and limited risk of spontaneous bleeding. These new drugs seem particularly suitable for stroke prevention in elderly patients with non-valvular atrial fibrillation in whom the hemorrhagic risk is high. Most of anti Factor XI (FXI) drugs are for parenteral use only. A group of small molecules are for oral use and therefore are candidates to substitute direct oral anticoagulants (DOACs) for stroke prevention in elderly patients with atrial fibrillation. Doubts remain on the possibility of impaired hemostasis. Indeed, a fine calibration of inhibition of contact phase factors is crucial for an effective and safe treatment.

Atrial cardiomyopathy and incident ischemic stroke risk: a systematic review and meta-analysis

BACKGROUND AND PURPOSE

Growing evidence suggests that atrial cardiomyopathy may play an essential role in thrombosis and ischemic stroke. The aim of this systematic review and meta-analysis was to quantify the values of cardiomyopathy markers for predicting ischemic stroke risk.

METHODS

PubMed, Embase, and the Cochrane Library were searched for longitudinal cohort studies evaluating the association between cardiomyopathy markers and incident ischemic stroke risk.

RESULTS

We included 25 cohort studies examining electrocardiographic, structural, functional, and serum biomarkers of atrial cardiomyopathy involving 262,504 individuals. P-terminal force in the precordial lead V1 (PTFV1) was found to be an independent predictor of ischemic stroke as both a categorical variable (HR 1.29, CI 1.06-1.57) and a continuous variable (HR 1.14, CI 1.00-1.30). Increased maximum P-wave area (HR 1.14, CI 1.06-1.21) and mean P-wave area (HR 1.12, CI 1.04-1.21) were also associated with an increased risk of ischemic stroke. Left atrial (LA) diameter was independently associated with ischemic stroke as both a categorical variable (HR 1.39, CI 1.06-1.82) and a continuous variable (HR 1.20, CI 1.06-1.35). LA reservoir strain independently predicted the risk of incident ischemic stroke (HR 0.88, CI 0.84-0.93). N-terminal pro-brain natriuretic peptide (NT-proBNP) was also associated with incident ischemic stroke risk, both as a categorical variable (HR 2.37, CI 1.61-3.50) and continuous variable (HR 1.42, CI 1.19-1.70).

CONCLUSION

Atrial cardiomyopathy markers, including electrocardiographic markers, serum markers, LA structural and functional markers, can be used to stratify the risk of incident ischemic stroke.

High-Sensitivity C-Reactive Protein Modifies P-Wave Terminal Force in Lead V1-Associated Prognosis in Acute Ischemic Stroke or TIA Patients

Little is known about the role of high-sensitivity C-reactive protein (hsCRP) in the relationship between P-wave terminal force in lead V1 (PTFV1) and stroke prognosis. We aimed to investigate how hsCRP influences the effect of PTFV1 on ischemic stroke recurrence and mortality. In this study, patients enrolled in the Third China National Stroke Registry, which enrolled consecutive patients who had suffered an ischemic stroke or transient ischemic attack in China, were analyzed. After excluding patients with atrial fibrillation, 8271 patients with PTFV1 and hsCRP measurements were included in this analysis. Cox regression analyses were used to assess the association between PTFV1 and stroke prognosis according to different inflammation statuses stratified by an hsCRP level of 3 mg/L. A total of 216 (2.6%) patients died, and 715 (8.6%) patients experienced ischemic stroke recurrence within 1 year. In patients with hsCRP levels ≥ 3 mg/L, elevated PTFV1 was significantly associated with mortality (HR, 1.75; 95% CI, 1.05-2.92; p = 0.03), while in those with hsCRP levels < 3 mg/L, such an association did not exist. In contrast, in patients with hsCRP levels < 3 mg/L and those with hsCRP levels ≥ 3 mg/L, elevated PTFV1 remained significantly associated with ischemic stroke recurrence. The predictive role of PTFV1 towards mortality but not ischemic stroke recurrence differed in terms of hsCRP levels.

Current perspectives on the clinical management of cryptogenic stroke

INTRODUCTION

Cryptogenic stroke is a heterogeneous entity defined as an ischemic stroke for which no probable cause is identified despite thorough diagnostic evaluation. Since about a quarter of all ischemic strokes are classified as cryptogenic, it is a commonly encountered problem for providers as secondary stroke prevention is guided by stroke etiology.

AREAS COVERED

In this review, the authors provide an overview of stroke subtype classification schemes and diagnostic evaluation in cryptogenic stroke. They then detail putative cryptogenic stroke mechanisms, their therapeutic implications, and ongoing research. This review synthesizes the available evidence on PubMed up to December 2022.

EXPERT OPINION

Cryptogenic stroke is an evolving concept that changes with ongoing research. Investigations are focused on improving our diagnostic capabilities and solidifying useful constructs within cryptogenic stroke that could become therapeutically targetable subgroups within an otherwise nonspecific entity. Advances in technology may help move specific proposed cryptogenic stroke mechanisms from undetermined to known source of ischemic stroke.

Atrial cardiomyopathy: Diagnosis, clinical implications and unresolved issues in anticoagulation therapy

Atrial cardiomyopathy (AC) is an evolving pathophysiological entity that has expanded our understanding regarding the atrium and its role in arrhythmogenesis and cardiac thromboembolism. The pathological myocardium in AC promotes arrhythmogenesis through mechanical dysfunction (hypocontractility, fibrosis), adverse alterations of the endothelium and secretion of prothrombotic factors (IL-6, IL-8, TNF-a). 'Red flags', indicative of AC, can be recognized either non-invasively by electrocardiography, echocardiography and cardiac magnetic resonance imaging or invasively by high-density electroanatomical mapping as low bipolar voltage areas of the affected myocardium. Signs of AC have been strongly associated with an increased risk of ischemic stroke, even embolic strokes of undetermined source, regardless of the coexistence of atrial fibrillation (AF). The underlying existence of AC has been negatively correlated with the success rate of catheter ablation of AF. The clinical value of AC is the provision of a novel pathway regarding the potential mechanisms of cerebrovascular events of cardiac thromboembolic origin. In addition, AC may serve as a risk stratification tool to predict the long-term responders of AF catheter ablation.

Left Atrial Mechanical Dysfunction and the Risk for Ischemic Stroke in People Without Prevalent Atrial Fibrillation or Stroke : A Prospective Cohort Study

BACKGROUND

Atrial myopathy-characterized by changes in left atrial function and size-may precede and promote atrial fibrillation (AF) and cardiac thromboembolism. In people without prior AF or stroke, whether analysis of left atrial function and size can improve ischemic stroke prediction is unknown.

OBJECTIVE

To evaluate the association of echocardiographic left atrial function (reservoir, conduit, and contractile strain) and left atrial size (left atrial volume index) with ischemic stroke and determine whether these measures can improve the stroke prediction achieved by CHA2DS2-VASc score variables.

DESIGN

Prospective cohort study.

SETTING

ARIC (Atherosclerosis Risk in Communities) study.

PARTICIPANTS

4917 ARIC participants without prevalent stroke or AF.

MEASUREMENTS

Ischemic stroke events (2011 to 2019) were adjudicated by physicians. Left atrial strain was measured using speckle-tracking echocardiography.

RESULTS

Over 5 years, the cumulative incidences of ischemic stroke in the lowest quintiles of left atrial reservoir, conduit, and contractile strain were 2.99% (95% CI, 1.89% to 4.09%), 3.18% (CI, 2.14% to 4.22%), and 2.15% (CI, 1.09% to 3.21%), respectively, and that of severe left atrial enlargement was 1.99% (CI, 0.23% to 3.75%). On the basis of the Akaike information criterion, left atrial reservoir strain plus CHA2DS2-VASc variables was the best predictive model. With the addition of left atrial reservoir strain to CHA2DS2-VASc variables, 11.6% of the 112 participants with stroke after 5 years were reclassified to higher risk categories and 1.8% to lower risk categories. Among the 4805 participants who did not develop stroke, 12.2% were reclassified to lower and 12.7% to higher risk categories. Decision curve analysis showed a predicted net benefit of 1.34 per 1000 people at a 5-year risk threshold of 5%.

LIMITATION

Underascertainment of subclinical AF.

CONCLUSION

In people without prior AF or stroke, when added to CHA2DS2-VASc variables, left atrial reservoir strain improves stroke prediction and yields a predicted net benefit, as shown by decision curve analysis.

PRIMARY FUNDING SOURCE

National Heart, Lung, and Blood Institute of the National Institutes of Health.

Atrial fibrillation and stroke

INTRODUCTION

Stroke is one of the leading causes of mortality and morbidity globally. Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. It is set to reach epidemic proportions. AF is associated with a five-fold increase in risk of stroke. Strokes caused by AF more often are fatal or result in severe disability. Even though the incidence of stroke has been significantly reduced by oral anticoagulation, AF is thought to account for a significant proportion of cryptogenic strokes where no etiology is identified.

AREAS COVERED

This article reviews the literature related to AF and stroke, pathophysiological insights, diagnosis of AF in stroke patients, and its management (Graphical Abstract).

EXPERT OPINION

The pathophysiology of thrombogenesis that links AF and stroke is not well understood and is an area of active research to identify new therapeutic targets to prevent AF and stroke. As the nature of AF and stroke is multifaceted, an integrated care approach to managing AF and stroke is increasingly essential.

Atrial cardiomyopathy markers predict ischemic cerebrovascular events independent of atrial fibrillation in patients with acute myocardial infarction

Background

Contemporary data on atrial cardiomyopathy (ACM) markers and ischemic cerebrovascular events (ICVE) in patients with acute myocardial infarction (AMI) is lacking. We aimed to examine whether ACM markers predict ICVE among AMI patients.

Materials and methods

A total of 4,206 AMI cases diagnosed in clinical examinations between January 2016 and June 2021 were assessed for markers of ACM including B-type natriuretic peptide (BNP), P-wave terminal force in ECG lead V1 (PTFV1), and left atrium diameter (LAD). Left atrial enlargement (LAE) and abnormal PTFV1 were defined by previously published cut-off points. The primary outcome was incident ICVE composed of ischemic stroke (IS) and transient ischemic attack (TIA). Receiver operating curve analyses were used to compare the predictive performance of the CHA2DS2-VASc score combined with ACM markers to the CHA2DS2-VASc score alone.

Results

During a median follow-up of 44.0 months, 229 (5.44%) ICVE occurred. Of these, 156 individuals developed IS and the remaining 73 cases were diagnosed with TIAs. The ICVE group showed larger PTFV1 and increased LAD as well as elevated BNP levels at baseline. In the multivariate analysis, we found significant associations with ICVE for PTFV1 (HR per 1,000 μV*ms, 1.143; 95% CI, 1.093–1.196), LAD (HR per millimeter, 1.148; 95% CI, 1.107–1.190), but not BNP after adjusting for known ICVE risk factors and interim atrial fibrillation (AF). The addition of abnormal PTFV1 and LAE improved the predictive accuracy of the CHA2DS2-VASc score with C-statistic increasing from 0.708 to 0.761 (p &lt; 0.001).

Conclusion

Atrial cardiomyopathy markers including PTFV1 and LAD were associated with incident ICVE independent of well-established risk factors and AF occurrence. The addition of ACM markers with CHA2DS2-VASc score may well discriminate individuals at high risk of ICVE in AMI patients.

Construction of a Clinical Predictive Model of Left Atrial and Left Atrial Appendage Thrombi in Patients with Nonvalvular Atrial Fibrillation

Background. The purpose of this study was to investigate the risk factors of left atrial (LA) or left atrial appendage (LAA) thrombi in patients with nonvalvular atrial fibrillation (NVAF) and to establish and validate relevant predictive models. It might improve thromboembolic risk stratification in patients with NVAF. Methods. This study retrospectively included 1210 consecutive patients with NVAF undergoing transesophageal echocardiography (TEE), of whom 139 patients had thrombi in LA or in LAA. Through literature review and the ten events per variable (10EPV) principle, 13 variables were finally identified for inclusion in multivariate analysis. Models were constructed by multivariate logistic stepwise regression and least absolute shrinkage and selection operator (lasso) regression. Results. After logistic regression, five variables (AF type, age, B-type natriuretic peptide, E/e’ ratio, and left atrial diameter) were finally screened out as model 1. After Lasso regression, AF type, age, gender, B-type natriuretic peptide, E/e’ ratio, left atrial diameter, and left ventricular ejection fraction were finally screened as model 2. After comparing the two models, the simpler model 1 was finally selected. The area under the ROC curve (AUC) of the model 1 was 0.865 (95% CI: 0.838–0.892), the Hosmer–Lemeshow test = 0.898, and the AUC = 0.861 after internal validation. The clinical decision curve showed that the new clinical prediction model could achieve a net clinical benefit when the expected threshold was between 0 and 0.6. Conclusion. This study constructed a new clinical prediction model of LA or LAA thrombi, with a higher discriminative degree than the CHADS2 and CHA2DS2-VASc scoring systems (AUC: 0.865 vs. 0.643; AUC: 0.865 vs 0.652).

Prognostic significance of atrial cardiopathy in patients with acute ischemic stroke

Introduction:

Whether atrial cardiopathy is associated with stroke prognosis remains unclear. We evaluated the association between atrial cardiopathy markers and outcomes in patients with ischemic stroke using a nationwide prospective registry.

Patients and methods:

Based on the Third China National Stroke Registry, we evaluated different atrial cardiopathy markers including increased P-wave terminal force in V1 (PTFV1), advanced interatrial block (aIAB), prolonged P-wave duration, prolonged P-wave dispersion, paroxysmal supraventricular tachycardia, premature atrial contractions, prolonged PR interval, and severe left atrial enlargement in ischemic stroke patients. The outcomes were death and ischemic stroke recurrence at 1 year. The association between atrial cardiopathy markers and outcomes was analyzed using Cox regression models.

Results:

At 1-year follow-up, 486 (3.4%) patients had died and 1317 (9.3%) patients had experienced ischemic stroke recurrence. After adjustment for clinical risk factors including atrial fibrillation, PTFV1 > 5000 μV·ms (adjusted hazard ratio [HR] 1.70, 95% confidence interval [CI]: 1.18–2.45, p = 0.004) and aIAB (adjusted HR 1.47, 95% CI: 1.14–1.91, p = 0.003) were significantly associated with mortality. PTFV1 > 5000 μV·ms was significantly associated with ischemic stroke recurrence (adjusted HR 1.54, 95% CI: 1.22–1.96, p = 0.0004). This association was observed although we excluded patients diagnosed with atrial fibrillation.

Discussion and Conclusion:

Atrial cardiopathy markers, especially PTFV1 and aIAB, are significantly associated with a higher risk of poor prognosis in patients with ischemic stroke.

Early diagnosis and better rhythm management to improve outcomes in patients with atrial fibrillation: the 8th AFNET/EHRA consensus conference

Despite marked progress in the management of atrial fibrillation (AF), detecting AF remains difficult and AF-related complications cause unacceptable morbidity and mortality even on optimal current therapy. This document summarizes the key outcomes of the 8th AFNET/EHRA Consensus Conference of the Atrial Fibrillation NETwork (AFNET) and the European Heart Rhythm Association (EHRA). Eighty-three international experts met in Hamburg for 2 days in October 2021. Results of the interdisciplinary, hybrid discussions in breakout groups and the plenary based on recently published and unpublished observations are summarized in this consensus paper to support improved care for patients with AF by guiding prevention, individualized management, and research strategies. The main outcomes are (i) new evidence supports a simple, scalable, and pragmatic population-based AF screening pathway; (ii) rhythm management is evolving from therapy aimed at improving symptoms to an integrated domain in the prevention of AF-related outcomes, especially in patients with recently diagnosed AF; (iii) improved characterization of atrial cardiomyopathy may help to identify patients in need for therapy; (iv) standardized assessment of cognitive function in patients with AF could lead to improvement in patient outcomes; and (v) artificial intelligence (AI) can support all of the above aims, but requires advanced interdisciplinary knowledge and collaboration as well as a better medico-legal framework. Implementation of new evidence-based approaches to AF screening and rhythm management can improve outcomes in patients with AF. Additional benefits are possible with further efforts to identify and target atrial cardiomyopathy and cognitive impairment, which can be facilitated by AI.

Multimodal Approach for the Prediction of Atrial Fibrillation Detected After Stroke: SAFAS Study

Background

Intensive screening for atrial fibrillation (AF) has led to a better recognition of this cause in stroke patients. However, it is currently debated whether AF Detected After Stroke (AFDAS) has the same pathophysiology and embolic risk as prior-to-stroke AF. We thus aimed to systematically approach AFDAS using a multimodal approach combining clinical, imaging, biological and electrocardiographic markers.

Methods

Patients without previously known AF admitted to the Dijon University Hospital (France) stroke unit for acute ischemic stroke were prospectively enrolled. The primary endpoint was the presence of AFDAS at 6 months, diagnosed through admission ECG, continuous electrocardiographic monitoring, long-term external Holter during the hospital stay, or implantable cardiac monitor if clinically indicated after discharge.

Results

Of the 240 included patients, 77 (32%) developed AFDAS. Compared with sinus rhythm patients, those developing AFDAS were older, more often women and less often active smokers. AFDAS patients had higher blood levels of NT-proBNP, osteoprotegerin, galectin-3, GDF-15 and ST2, as well as increased left atrial indexed volume and lower left ventricular ejection fraction. After multivariable analysis, galectin-3 ≧ 9 ng/ml [OR 3.10; 95% CI (1.03–9.254), p = 0.042], NT-proBNP ≧ 290 pg/ml [OR 3.950; 95% CI (1.754–8.892, p = 0.001], OPG ≥ 887 pg/ml [OR 2.338; 95% CI (1.015–5.620), p = 0.046) and LAVI ≥ 33.5 ml/m2 [OR 2.982; 95% CI (1.342–6.625), p = 0.007] were independently associated with AFDAS.

Conclusion

A multimodal approach combining imaging, electrocardiography and original biological markers resulted in good predictive models for AFDAS. These results also suggest that AFDAS is probably related to an underlying atrial cardiopathy.

Clinical Trial Registration

[www.ClinicalTrials.gov], identifier [NCT03570060].

Signs of left atrial disease and 10-year risk of atrial fibrillation

Background

The contribution of left atrial disease and excessive supraventricular ectopic activity (ESVEA) to the risk for incident atrial fibrillation (AF) is incompletely understood.

Objective

To analyse the ten-year risk to develop AF in patients with cardiovascular risk factors and to define the impact of parameters of left atrial disease and ESVEA on AF risk.

Methods

148 patients from the Diast-CHF trial with at least one cardiovascular risk factor and free of AF at baseline were followed for 10 years. Left atrial disease was defined as left atrial volume index (LAVI) >35 ml/m², P-terminal force in lead V₁ (PTFV₁) >4000 ms*μV or elevated N-terminal pro-B-type natriuretic peptide (NT-proBNP) >250 pg/ml. We analyzed the association of these parameters and ESVEA (either >720 premature atrial contractions (PAC) or one atrial run >20 beats per day) on AF-free survival.

Results

After ten years, AF was newly detected in twelve patients (13.4%) with signs of left atrial disease and two patients (3.4%) without signs of left atrial disease (p = 0.04). LAVI (p = 0.005), ESVEA (p = 0.016) and NT-proBNP (p = 0.010) were significantly associated with AF-free survival in univariate analysis. A combined Cox model of left atrial disease parameters showed associations for NT-proBNP (HR 3.56; 95%CI 1.33–5.31; p = 0.04) and PAC (HR 2.66; 95%CI 1.25–10.15; p = 0.01) but not for LAVI or PTFV₁ with AF-free survival.

Conclusion

The risk for AF is higher in patients with cardiovascular risk factors and signs of left atrial disease. NT-proBNP and premature atrial contractions independently predict AF-free survival. The role of excessive supraventricular ectopic activity for the assessment of AF risk may be underestimated and requires further study.

Cardiac Risk Factors for Stroke: A Comprehensive Mendelian Randomization Study

BACKGROUND

Observational studies suggest an association of stroke with cardiac traits beyond atrial fibrillation, the leading source of cardioembolism. However, controversy remains regarding a causal role of these traits in stroke pathogenesis. Here, we leveraged genetic data to systematically assess associations between cardiac traits and stroke risk using a Mendelian Randomization framework.

METHODS

We studied 66 cardiac traits including cardiovascular diseases, magnetic resonance imaging-derived cardiac imaging, echocardiographic imaging, and electrocardiographic measures, as well as blood biomarkers in a 2-sample Mendelian Randomization approach. Genetic predisposition to each trait was explored for associations with risk of stroke and stroke subtypes in data from the MEGASTROKE consortium (40 585 cases/406 111 controls). Using multivariable Mendelian Randomization, we adjusted for potential pleiotropic or mediating effects relating to atrial fibrillation, coronary artery disease, and systolic blood pressure.

RESULTS

As expected, we observed strong independent associations between genetic predisposition to atrial fibrillation and cardioembolic stroke and between genetic predisposition to coronary artery disease as a proxy for atherosclerosis and large-artery stroke. Our data-driven analyses further indicated associations of genetic predisposition to both heart failure and lower resting heart rate with stroke. However, these associations were explained by atrial fibrillation, coronary artery disease, and systolic blood pressure in multivariable analyses. Genetically predicted P-wave terminal force in V1, an electrocardiographic marker for atrial cardiopathy, was inversely associated with large-artery stroke.

CONCLUSIONS

Available genetic data do not support substantial effects of cardiac traits on the risk of stroke beyond known clinical risk factors. Our findings highlight the need to carefully control for confounding and other potential biases in studies examining candidate cardiac risk factors for stroke.

Atrial Cardiopathy and Cryptogenic Stroke

Recent advances in pathophysiology suggest that a pathological atrial substrate can cause embolic stroke even in patients without atrial fibrillation (AF). This pathological condition is called “atrial cardiopathy”, which indicates atrial structural and functional disorders that can precede AF. The objective of this narrative review was to provide a current overview of atrial cardiopathy and cryptogenic stroke. We searched the PubMed database and summarized the recent findings of the identified studies, including the pathogenesis of atrial cardiopathy, biomarkers of atrial cardiopathy, relationship between atrial cardiopathy and cryptogenic stroke, and therapeutic interventions for atrial cardiopathy. Abnormal atrial substrate (atrial cardiopathy) that leads to AF can result in embolic stroke before developing AF, and may explain the source of cryptogenic stroke in some patients. Although there are several potential biomarkers indicative of atrial cardiopathy, P-wave terminal force in lead V1 (>5,000 μV^* ms), N-terminal pro-brain natriuretic peptide (>250 pg/ml), and left atrial enlargement are currently promising biomarkers for the diagnosis of atrial cardiopathy. Because the optimal combination and thresholds of biomarkers for diagnosing atrial cardiopathy remain uncertain, atrial cardiopathy represents a spectrum disorder. The concept of atrial cardiopathy appears to be most valuable as a starting point for therapeutic intervention to prevent stroke. Validation of the diagnosis of atrial cardiopathy and whether it can be used as a new therapeutic target for direct oral anticoagulants are currently being covered in the ARCADIA trial.

From the Heart to the Brain: Building Bridges to a Better Future

This Presidential Address was delivered at the International Stroke Conference in March 2021, during the coronavirus pandemic. Dr Elkind, the President of the American Heart Association (AHA) at the time, is a vascular neurologist with a research focus on stroke epidemiology. This address interweaves personal reflections on a career in clinical neurology, stroke research, and public health with a discussion of the role of the AHA in improving cardiovascular health at multiple levels. Throughout its history, the AHA has had leaders representing many different areas of cardiovascular science and medicine, including stroke. More recently, its focus has expanded from a traditional emphasis on cardiovascular events illness and events, like heart disease and stroke, to an appreciation of the role of the vascular system in brain health, healthy aging, cognitive decline, and dementia. During the pandemic, as the bidirectional effects of the coronavirus on cardiovascular disease has been elucidated, the benefits of a broad and multidisciplinary approach to cardiovascular disease and public health have become more apparent than ever. In addition, with growing awareness of the disproportionate effects of the pandemic on communities of color in the United States and globally, the AHA has redoubled its focus on addressing the social determinants of health, including structural racism. Central to these efforts is the construction of bridges between the generation of scientific knowledge and action for the public good. Our success will depend on the combination of basic, translational, clinical and population research with programs of public and professional education, advocacy, and social action.

N-Terminal Pro-brain Natriuretic Peptide Is Associated With Hemorrhagic Transformation and Poor Outcomes in Patients With Stroke Treated With Intravenous Thrombolysis

Background: N-terminal pro-brain natriuretic peptide (NT-proBNP) levels are a promising biomarker for predicting stroke outcomes; however, their prognostic validity is not well-understood in patients who have undergone intravenous thrombolysis. This study was designed to evaluate the prognostic value of NT-proBNP levels in patients with acute ischemic stroke treated with intravenous thrombolysis.

Methods: Patients with ischemic stroke who underwent intravenous thrombolysis between April 2015 and December 2020 were analyzed. Demographic information, information related to intravenous thrombolysis, medical history, and laboratory test results were collected. Outcomes, such as hemorrhagic transformation, early neurologic deterioration, poor 3-month functional outcomes, and 3-month mortality were recorded. Correlations between NT-proBNP levels and the above outcomes were analyzed, an individualized prediction model based on NT-proBNP levels for functional outcomes was developed, and a nomogram was drafted.

Results: A total of 404 patients were included in the study. Elevated NT-proBNP levels were independently associated with hemorrhagic transformation, poor 3-month functional outcomes, and 3-month mortality, while early neurological deterioration was not. An association between NT-proBNP levels and hemorrhagic transformation was noted. An individualized prediction model for poor functional outcomes was established, which was composed of ln(NT-proBNP), National Institutes of Health Stroke Scale (NIHSS), and baseline glucose, with good discrimination [area under the curve (AUC) 0.764] and calibration (P > 0.05).

Conclusion: To the best of our knowledge, this is the first report on the association between NT-proBNP levels and hemorrhagic transformation in patients who have undergone intravenous thrombolysis. The 3-month functional outcomes and mortality were found to be associated with NT-proBNP levels. An individualized prediction model based on NT-proBNP levels to predict the 3-month functional outcomes was established. Our results suggest that NT-proBNP levels could be used as a prognostic biomarker in patients with acute ischemic stroke treated with intravenous thrombolysis.

Embolic Stroke of Undetermined Source: Approaches in Risk Stratification for Cardioembolism

Ischemic stroke is a leading cause of morbidity and mortality worldwide. Embolic stroke of undetermined source has been recently proposed to categorize nonlacunar ischemic strokes without confirmed etiology after adequate investigation with a likely embolic stroke mechanism. A strategy of empirical anticoagulation for embolic stroke of undetermined source patients is attractive but may only be beneficial in a select subset of patients. Strategies which would help identify the subset of embolic stroke of undetermined source patients most likely to have cardioembolic origin of stroke, and hence benefit from anticoagulation, are needed. This article will review current evidence which may be useful in the development of a risk stratification approach based on arrhythmia monitoring, cardiac imaging, and clinical risk stratification. This approach may be beneficial in clinical practice in improving patient outcomes and reducing stroke recurrence in this population; however, further work is required with active trials underway.

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

OBJECTIVES

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.

METHODS

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.

RESULTS

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 34 months, 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.

DISCUSSION

ESUS patients with AC have different baseline clinical characteristics than patients without AC and have a higher detection of AF during follow-up.

Mechanical concordance between left atrium and left atrial appendage in nonvalvular atrial fibrillation: can it be exploited to avoid transesophageal echocardiography prior to electrical cardioversion during Covid-19 pandemic?

Transesophageal echocardiography (TEE) is the gold standard for assessing left atrial appendage (LAA) mechanic and thrombosis (LAAT); however, TEE is a high-risk procedure for viral transmission during coronavirus disease 2019 (COVID-19) pandemic. We investigated whether deformation indices of left atrium (LA) at transthoracic echocardiography (TTE) correlate with those of LAA assessed by TEE in nonvalvular atrial fibrillation (NVAF) patients undergoing electrical cardioversion (ECV). Consecutive patients with NVAF of ≥ 48 h or unknown duration, who underwent TEE and TTE at our Institution before ECV were retrospectively investigated. Standard echo-Doppler and LA and LAA myocardial strain and strain rate parameters were analyzed. A total of 115 NVAF patients (71.3 ± 8.1 yr/o, 59.1% men) were included: LAAT was diagnosed in 25 (21.7%) patients. Compared to patients without LAAT, those with LAAT had significantly higher CHA₂DS₂-VASc Risk score (4.5 ± 1.4 vs. 3.5 ± 1.1, p < 0.001), and lower ejection fraction (46.0 ± 14.8 vs. 57.6 ± 8.6%, p < 0.001). In LAAT patients, global strain of LA (8.7 ± 2.6 vs. 16.3 ± 4.5%, p < 0.001) and LAA (7.0 ± 1.7 vs. 11.7 ± 2.0%, p < 0.001) was significantly reduced compared to non-LAAT patients. A close relationship between left atrial strain reservoir (LASr) and LAA-global strain was demonstrated (r = 0.81). By univariable analysis, CHA₂DS₂-VASc Risk Score (OR 2.01, 95%CI 1.34–3.00), NT-proBNP (OR 1.36, 95%CI 1.19–1.54), ejection fraction (OR 0.92, 95%CI 0.88–0.96), E/e’ ratio (OR 2.07, 95%CI 1.51–2.85), and LASr (OR 0.39, 95%CI 0.25–0.62) were strongly associated with LAAT presence at TEE. By multivariable analysis, only LASr (OR 0.40, 95%CI 0.24–0.70) retained statistical significance. ROC curve analysis revealed that an LASr cut-off value ≤ 9.3% had 98.9% sensibility and 100% specificity to identify LAAT by TEE (AUC = 0.98). In patients with NVAF of ≥ 48 h or unknown duration, scheduled to undergo ECV, LA deformation assessment by TTE might substitute invasive measurement of LAA function by TEE, simplifying diagnostic approach and possibly contributing to reduce COVID-19 infection diffusion.

Rapid Risk Stratification of Acute Ischemic Stroke Patients in the Emergency Department: The Incremental Prognostic Role of Left Atrial Reservoir Strain

OBJECTIVES

To determine the prognostic value of positive global left atrial strain (LA-GSA+), measured by two-dimensional speckle tracking echocardiography (2D-STE) in a population of acute ischemic stroke (AIS) patients without atrial fibrillation (AF), in the setting of Emergency Department (ED).

METHODS

All consecutive AIS patients with sinus rhythm on ECG and without AF history entered this prospective study. All patients underwent complete blood tests and transthoracic echocardiography implemented with 2D-STE analysis of LA strain parameters within 6-12 h after symptoms onset. At 6-months follow-up, we evaluated the composite endpoint of all-cause mortality plus cardiovascular re-hospitalizations.

RESULTS

A total of 102 AIS patients (76.4 ± 10.8 yrs, 47% males) were prospectively included. LA-GSA+ was markedly reduced in AIS patients (20.8 ± 7.7%), without any statistically significant difference between the stroke subtypes. At 6-months follow-up, 7 deaths and 27 re-hospitalizations occurred. On multivariate Cox regression analysis, variables independently associated with outcome were: LA-GSA+ (per unit) (HR 0.29, 95% CI 0.19-0.39) and C-reactive protein (CRP) (per 0.1 mg/dl) (HR 1.45, 95% CI 1.15-1.75) as continuous variables; statin therapy (HR 0.45, 95%CI 0.28-0.62), and type 2 diabetes (HR 1.65, 95% CI 1.15-2.35) as categorical variables. A LA-GSA+ ≤20.0% predicted the occurrence of the above-mentioned outcome at 6-months follow-up with 94% sensitivity and 81% specificity (AUC=0.84). Interestingly, GSA+ showed a strong inverse correlation with CRP levels (r = -0.86).

CONCLUSIONS

A LA-GSA+ ≤20% reflects a more advanced atrial cardiomyopathy and might provide a rapid and reliable prognostic risk stratification of AIS patients without AF history in the setting of ED.

Atrial Cardiomyopathy: An Emerging Cause of the Embolic Stroke of Undetermined Source

Nearly 30% of ischemic strokes have an unknown cause, which are referred to as cryptogenic strokes (CS). Imaging studies suggest that a large proportion of these patients show features that are consistent with embolism, and thus the term embolic stroke of undetermined source (ESUS) was proposed to describe these CS patients. Atrial cardiomyopathy predisposes to thrombus formation and thus embolic stroke even in the absence of atrial fibrillation (AF). This may provide a mechanistic link with ESUS, suggesting that anticoagulant therapy may be more beneficial than antiplatelet therapy in ESUS patients with atrial cardiomyopathy. The present review discusses the concept of atrial cardiomyopathy and ESUS and the relationship between them based on the mechanisms and clinical evidence, suggests that atrial cardiomyopathy may be a potential mechanism of ESUS, and highlights a theoretical basis that supports that anticoagulant therapy may be more applicable to ESUS patients with atrial cardiomyopathy and aims to help us better understand and identify the risk of ESUS, thereby improving the management of these patients in clinical practice.

Abnormal P-wave terminal force in lead V1 is a marker for atrial electrical dysfunction but not structural remodelling

Aims

There is a lack of diagnostic and therapeutic options for patients with atrial cardiomyopathy and paroxysmal atrial fibrillation. Interestingly, an abnormal P‐wave terminal force in electrocardiogram lead V₁ (PTFV₁) has been associated with atrial cardiomyopathy, but this association is poorly understood. We investigated PTFV₁ as a marker for functional, electrical, and structural atrial remodelling.

Methods and results

Fifty‐six patients with acute myocardial infarction and 13 kidney donors as control cohort prospectively underwent cardiac magnetic resonance imaging to evaluate the association between PTFV₁ and functional remodelling (atrial strain). To further investigate underlying pathomechanisms, right atrial appendage biopsies were collected from 32 patients undergoing elective coronary artery bypass grafting. PTFV₁ was assessed as the product of negative P‐wave amplitude and duration in lead V₁ and defined as abnormal if ≥4000 ms*μV. Activity of cardiac Ca/calmodulin‐dependent protein kinase II (CaMKII) was determined by a specific HDAC4 pull‐down assay as a surrogate for electrical remodelling. Atrial fibrosis was quantified using Masson's trichrome staining as a measure for structural remodelling. Multivariate regression analyses were performed to account for potential confounders. A total of 16/56 (29%) of patients with acute myocardial infarction, 3/13 (23%) of kidney donors, and 15/32 (47%) of patients undergoing coronary artery bypass grafting showed an abnormal PTFV₁. In patients with acute myocardial infarction, left atrial (LA) strain was significantly reduced in the subgroup with an abnormal PTFV₁ (LA reservoir strain: 32.28 ± 12.86% vs. 22.75 ± 13.94%, P = 0.018; LA conduit strain: 18.87 ± 10.34% vs. 10.17 ± 8.26%, P = 0.004). Abnormal PTFV₁ showed a negative correlation with LA conduit strain independent from clinical covariates (coefficient B: −7.336, 95% confidence interval −13.577 to −1.095, P = 0.022). CaMKII activity was significantly increased from (normalized to CaMKII expression) 0.87 ± 0.17 to 1.46 ± 0.15 in patients with an abnormal PTFV₁ (P = 0.047). This increase in patients with an abnormal PTFV₁ was independent from clinical covariates (coefficient B: 0.542, 95% confidence interval 0.057 to 1.027, P = 0.031). Atrial fibrosis was significantly lower with 12.32 ± 1.63% in patients with an abnormal PTFV₁ (vs. 20.50 ± 2.09%, P = 0.006), suggesting PTFV₁ to be a marker for electrical but not structural remodelling.

Conclusions

Abnormal PTFV₁ is an independent predictor for impaired atrial function and for electrical but not for structural remodelling. PTFV₁ may be a promising tool to evaluate patients for atrial cardiomyopathy and for risk of atrial fibrillation.

Impact of Left Atrial Appendage Morphology on Recurrence in Embolic Stroke of Undetermined Source and Atrial Cardiopathy

Background: The left atrial appendage (LAA) is a major source of thrombus and non-chicken wing (CW). LAA morphology is a risk factor for embolic events in atrial fibrillation. However, the association of non-CW morphology with embolic stroke recurrence is unknown in patients with embolic stroke of undetermined source (ESUS) and atrial cardiopathy.

Methods: We conducted retrospective analyses using a prospective institutional stroke registry (2013–2017). Patients with ESUS and atrial cardiopathy were enrolled. Atrial cardiopathy was diagnosed if an increased left atrial diameter (>40 mm, men; >38 mm, women), supraventricular tachycardia, or LAA filling defect on computed tomography (CT) were present. Patients admitted >24 h after onset were excluded. LAA morphology was evaluated using CT and categorized into CW vs. non-CW types. The primary outcome was embolic stroke recurrence. Multivariable Cox proportional hazards models were used to examine the independent association between LAA morphology and outcome.

Results: Of 157 patients, 81 (51.6%) had CW LAA morphology. The median follow-up was 41.5 (interquartile range 12.3–58.5) months corresponding to 509.8 patient years. In total, 18 participants experienced embolic stroke recurrences (3.80 per 100 patient-years). Non-CW morphology was more associated with embolic stroke recurrence than CW morphology (hazard ratio (HR), 3.17; 95% confidence interval (CI), 1.13–8.91; p = 0.029). After adjusting for CHA₂DS₂-VASc score and number of potential embolic sources, non-CW morphology showed an independent association with outcome (adjusted HR, 2.90; 95% CI, 1.02–8.23; p = 0.045).

Conclusions: The LAA morphology types may help identify high risk of embolic stroke recurrence in ESUS with atrial cardiopathy. LAA morphology in atrial cardiopathy may provide clues for developing therapies tailored to specific mechanisms.

Atrial Cardiopathy Biomarkers and MRI-Based Infarct Patterns in Patients with Embolic Strokes of Undetermined Source

OBJECTIVES

The study aimed to investigate whether N-terminal pro-B-type natriuretic peptide (NT-proBNP) concentration and/or left atrial volume index (LAVI), as atrial cardiopathy biomarkers, were associated with infarct patterns on diffusion-weighted imaging in patients with embolic strokes of undetermined source (ESUS).

MATERIALS AND METHOD

We retrospectively evaluated patient with ESUS from our stroke registry between January 2018 and November 2019. Cut-off values for atrial cardiopathy biomarkers were defined as >250 pg/mL for NT-proBNP and >34 mL/m² for LAVI. Eligible patients were then assigned to 3 groups and infarct patterns were compared according to their atrial cardiopathy markers: Group 1 (no atrial cardiopathy markers), Group 2 (one marker), and Group 3 (both markers).

RESULTS

Among 194 eligible patients with ESUS (76 women; mean age, 69.2 years), simultaneous increases of NT-proBNP concentration and LAVI were identified in 39 (20.1%). Group 3 had a significantly larger infarct volume, relative to Group 1 and Group 2 (P=0.043) Multivariable logistic regression analyses revealed that these patients (Group 3) were significantly more likely to have multi-territorial infarcts (adjusted odds ratio [aOR]: 3.03, 95% confidence interval [CI]: 1.05-8.72; P=0.04), a maximal lesion diameter >15mm (aOR: 4.51, 95% CI: 1.70-11.93; P=0.001), and large cortical infarctions (aOR: 4.17, 95% CI: 1.75-9.96; P=0.001).

CONCLUSION

We found that simultaneously increased values for NT-proBNP concentration and LAVI were independently associated with multi-territorial and large cortical infarct patterns in patients with ESUS. These findings suggest that NT-proBNP and LAVI may be useful biomarkers for identifying cardioembolic subtypes and guiding treatment selection in patients with ESUS.

Left atrial dimension and ischemic stroke in patients with and without atrial fibrillation

The incidence of ischemic stroke (IS) increases in patients with enlarged left atrium (LA) irrespective of whether or not the existence of atrial fibrillation (AF). In such situation, it is unclear whether the impact of LA on incidence of IS still significant in young, non-AF patients with enlarged LA who are primarily unconcerned on anticoagulation therapy. The study population consisted of 18,511 consecutive patients not receiving oral anticoagulants and undergoing echocardiography with measurement of LAD at baseline. The incidence rate of ischemic stroke was calculated in 3 groups according to left atrial dimension (LAD; < 30, 30-45 and ≥ 45 mm) in AF and non-AF patients. Further subgroup analysis was performed in stratification by elderly and young (aged ≥ 65 and < 65 years, respectively). The incidences of IS (per 100 patient-years) were 0.11 and 0.71 in non-AF and AF patients with LAD < 30 mm, respectively, which increased to 0.58 and 1.35 in LAD ≥ 45 mm (adjusted hazard ratios [HRs]; 1.95 [95% confidence intervals, CIs: 0.76-5.01] and 1.22 [95% CIs: 0.27-5.58], interaction P was 0.246). In non-AF patients, the incidences of IS were 0.30 and 0.04 in elderly and young patients with LAD < 30 mm, which increased to 0.67 and 0.48 in LAD ≥ 45 mm (adjusted HRs; 1.34 [95% CIs: 0.43-4.15] and 4.21 [95% CIs: 0.77-23.12], interaction P was 0.158). The incidence of IS significantly increased with increase of LAD in non-AF, especially in non-AF and young patients, although the difference was not independent of other clinical factors. The impact of LAD on IS was numerically larger in non-AF than in AF, and larger in young and non-AF than in elderly counterpart, although a significant interaction was not observed in this small population. Further studies with large population are necessary to judge whether these population with enlarged LA need antithrombotic therapy.

Atrial fibrillation and atrial cardiomyopathies

Atrial fibrillation (AF) is the most common arrhythmia among adults. While there have been incredible advances in the management of AF and its clinical sequelae, investigation of atrial cardiomyopathies (ACMs) is becoming increasingly more prominent. ACM refers to the electromechanical changes-appreciated subclinically and/or clinically-that underlie atrial dysfunction and create an environment ripe for the development of clinically apparent AF. There are several subtypes of ACM, distinguished by histologic features. Recent progress in cardiovascular imaging, including echocardiography with speckle-tracking (e.g., strain analysis), cardiovascular magnetic resonance imaging (CMR), and atrial 4-D flow CMR, has enabled increased recognition of ACM. Identification of ACM and its features carry clinical implications, including elevating a patient's risk for development of AF, as well as associations with outcomes related to catheter-based and surgical AF ablation. In this review, we explore the definition and classifications of ACM, its complex relationship with clinical AF, imaging modalities, and clinical implications. We propose next steps for a more unified approach to ACM recognition that can direct further research into this complex field.