Stroke type and severity in patients with subclinical atrial fibrillation: An analysis from the Asymptomatic Atrial Fibrillation and Stroke Evaluation in Pacemaker Patients and the Atrial Fibrillation Reduction Atrial Pacing Trial (ASSERT)

Antithrombotic therapy in patients with atrial high-rate episodes (AHREs): Current evidence and open questions

With the increasing use of cardiac electronic implantable devices in recent years, the identification of asymptomatic atrial arrhythmias, including atrial high-rate episodes (AHREs) and device-detected subclinical atrial fibrillation (SCAF), has become common in clinical practice. AHREs have potentially important clinical implications because they are considered precursors of atrial fibrillation (AF). Although to a lesser extent than clinical AF, both AHREs and device-detected SCAF are associated with thromboembolic events, however routine use of anticoagulants in these conditions is not recommended. In addition, patients with AHREs are at increased risk of cardiovascular events, including myocardial infarction, heart failure, and cardiovascular hospitalization. The relationship between stroke and AHREs and the potential benefit of anticoagulant therapy in this setting is the subject of ongoing debate. In this review, we aimed to appraise the available evidence and current gaps in the risk stratification and management of patients with AHREs/device-detected SCAF.

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society, the Asia Pacific Heart Rhythm Society, and the Latin American Heart Rhythm Society.

Characteristics of Patients With Asymptomatic Atrial Fibrillation and Ischemic Stroke-Insights From the GLORIA-AF Registry (Phase 2)

BACKGROUND

Asymptomatic nonvalvular atrial fibrillation is often suspected in patients with cryptogenic stroke which constitute 20%-30% of ischemic strokes. Detection of atrial fibrillation (AF) and treatment with anticoagulation can reduce the risk of stroke. We sought to investigate the prevalence of asymptomatic atrial fibrillation (aAF) in patients with a history of stroke or an acute stroke on admission.

METHODS

From November 2011 until December 2014, 15,308 patients with a first episode of AF were enrolled in phase 2 of the international, prospective, multicenter global registry on long-term oral anticoagulation treatment in patients with AF (GLORIA-AF) Registry. For the present analysis, we focused on patients with aAF regarding the prevalence of stroke.

RESULTS

One third of patients (n = 4892, 32%) had aAF. Of these, 611 (12.5%) had a history of stroke or an acute stroke on admission. In contrast, 519 of 10,416 (5.0%) patients with symptomatic AF (sAF) had a history of stroke or an acute stroke on admission. Higher age, male gender, permanent AF, stroke, and the combination of stroke, TIA or systemic embolism were associated with a higher prevalence of aAF on admission. In a multivariable analysis, patients with aAF had a 2.3-fold (95% confidence interval (CI), 2.02-2.54) risk for stroke compared to patients with sAF. Other independent risk factors for stroke were a history of prior bleeding (odds ratio 1.62, 95% CI, 1.34-1.92), chronic kidney disease (1.38, 1.21-1.56), and diabetes mellitus (1.24, 1.10-1.41).

CONCLUSION

aAF is reported in about one third of patients with newly diagnosed AF and is associated with a 2.3-fold risk for stroke compared to sAF. Therefore, screening for aAF in high-risk patients might be appropriate to prevent further embolic cerebrovascular events.

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society, the Asia Pacific Heart Rhythm Society, and the Latin American Heart Rhythm Society.

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society (HRS), the Asia Pacific HRS, and the Latin American HRS.

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society, the Asia Pacific Heart Rhythm Society, and the Latin American Heart Rhythm Society .

Association between antithrombotic therapy after stroke in patients with atrial fibrillation and the risk of net clinical outcome: an observational cohort study

AIMS

Data on the optimal use of antithrombotic drugs and associated clinical outcomes in patients with atrial fibrillation (AF) and acute ischaemic stroke (IS) are limited. We investigated the prescription patterns of antithrombotics in community practice and long-term clinical prognosis according to early post-stroke antithrombotic therapy in patients with AF and acute IS.

METHODS AND RESULTS

Patients with AF who were admitted for acute IS at a single tertiary hospital in 2010-2020 were retrospectively reviewed. Clinical profiles including the aetiology of stroke and prescription patterns of antithrombotics were identified. The net clinical outcome (NCO)-the composite of recurrent stroke, any bleeding, hospitalization or emergency department visits for cardiovascular (CV) events, and death-was compared according to the antithrombotic therapy at the first outpatient clinic visit [oral anticoagulation (OAC) alone vs. antiplatelet (APT) alone vs. OAC/APT(s)] following discharge. A total of 918 patients with AF and acute IS (mean age, 72.6 years; male, 59.3%; mean CHA₂DS₂-VASc score 3.3) were analysed. One-third (33.9%, n = 310) of patients were simultaneously diagnosed with AF and IS. The most common aetiology of IS was cardioembolism (71.2%), followed by undetermined aetiology (19.8%) and large artery atherosclerosis (6.0%). OAC, APT(s), and concomitant OAC and APT(s) were prescribed in 33.4%, 11.1%, and 53.4% of patients during admission that changed to 67.0%, 9.1%, and 21.7% at the first outpatient clinic, and were mostly continued up to one year after IS. Non-prescription of OAC was observed in 11.3% of post-stroke patients with AF. During a median follow-up of 2.1 years, the overall incidence rate of NCO per 100 patient-year (PY) was 20.14. APT(s) monotherapy presented the highest cumulative risk of NCO (adjusted hazard ratio 1.47, 95% confidence interval 1.08-2.00, P = 0.015; with reference to OAC monotherapy) mainly driven by the highest rates of recurrent stroke and any bleeding. OAC/APT(s) combination therapy was associated with a 1.62-fold significantly higher risk of recurrent stroke (P = 0.040) and marginally higher risk of any bleeding than OAC monotherapy.

CONCLUSION

Approximately one-third of acute IS in AF have a distinctive mechanism from cardioembolism. Although APT was frequently prescribed in post-stroke patients with AF, no additive clinical benefit was observed. Adherence to OAC treatment is essential to prevent further CV adverse events in patients with AF and IS.

Towards a new classification of atrial fibrillation detected after a stroke or a transient ischaemic attack

Globally, up to 1·5 million individuals with ischaemic stroke or transient ischaemic attack can be newly diagnosed with atrial fibrillation per year. In the past decade, evidence has accumulated supporting the notion that atrial fibrillation first detected after a stroke or transient ischaemic attack differs from atrial fibrillation known before the occurrence of as stroke. Atrial fibrillation detected after stroke is associated with a lower prevalence of risk factors, cardiovascular comorbidities, and atrial cardiomyopathy than atrial fibrillation known before stroke occurrence. These differences might explain why it is associated with a lower risk of recurrence of ischaemic stroke than known atrial fibrillation. Patients with ischaemic stroke or transient ischaemic attack can be classified in three categories: no atrial fibrillation, known atrial fibrillation before stroke occurrence, and atrial fibrillation detected after stroke. This classification could harmonise future research in the field and help to understand the role of prolonged cardiac monitoring for secondary stroke prevention with application of a personalised risk-based approach to the selection of patients for anticoagulation.

Vascular Endothelial Dysfunction and Immunothrombosis in the Pathogenesis of Atrial Fibrillation

Atrial Fibrillation (AF) induces proinflammatory processes which incite vascular endothelial activation and dysfunction. This study seeks to examine the potential relationship between various endothelial, inflammatory, thrombotic, and renin-angiotensin-system (RAS) biomarkers in AF patients.Blood samples were from AF patients (n = 110) prospectively enrolled in this study prior to their first AF ablation. Control plasma samples (n = 100) were used as reference. All samples were analyzed for endothelial (NO, ICAM-1, VEGF, TF, TFPI, TM, Annexin V), inflammatory (IL-6, TNFα, CRP), thrombotic (vWF, tPA, PAI-1, TAFI, D-dimer), and RAS (Renin, Ang-II) biomarkers using ELISA methods. Biomarker average comparisons and Spearman correlations were performed.AF patients showed varying levels of biomarker increase compared to controls. We observed a significant decrease of Ang-II in the AF population relative to controls when stratified for the use of angiotensin-converting enzyme inhibitor (ACEI) or angiotensin II receptor blocker (ARB) upon study enrollment. AF patients showed statistically significant correlations between the following biomarkers: TNFα vs IL-6 (rs = 0.317, p = .004), ICAM-1 vs TNFα (rs = 0.527, p = .012), Annexin V vs VEGF (rs = 0.620, p < .001), CRP vs VEGF (rs = 0.342, p = .031), Ang-II vs tPA (rs = -0.592, p = .010), and tPA vs PAI-1 (rs = 0.672, p < .001).Our study demonstrated significant elevation of endothelial, inflammatory, and thrombotic biomarkers in AF patients compared to controls, with significant correlations between these biomarkers in the AF population. Future investigations are required to better elucidate the mechanistic pathways that lead to endothelial dysfunction and thromboinflammation in AF. This may provide novel therapeutic targets, that in addition to current anticoagulation practices, can best curtail thrombogenicity in AF.

Utility of speckle-tracking echocardiography for predicting atrial fibrillation following ischemic stroke: a systematic review and meta-analysis

Undiagnosed atrial fibrillation (AF) is one of the main sources of cryptogenic stroke. And strain indices measured by speckle-tracking echocardiography are associated with atrial remodeling supposed to be the substrate of AF. Therefore, there is a strong need for evaluating the utility of speckle-tracking echocardiography to predict the likelihood of AF in patients with cryptogenic stroke. PubMed, Embase and Cochrane Database were searched for studies. The random-effects model was used to calculate the pooled results, and summary receiver operating characteristic curve (SROC) analysis was performed to show the overall predictive value. There were 1483 patients with cryptogenic stroke from 8 studies. Meta-analysis showed that strain indices including global longitudinal strain (GLS) (mean difference [SMD]: - 0.22, 95% confidence interval [95% CI] - 0.40 to - 0.04), left atrial reservoir strain (εR), (SMD: - 0.87, 95% CI - 1.26 to - 0.48, conduit strain (εCD) (SMD: - 0.56, 95% CI - 0.81 to - 0.30), contractile strain (εCT) (SMD: - 1.00, 95% CI - 1.39 to - 0.61), and left atrial reservoir strain rate (SRe) (SMD: - 0.54, 95% CI - 0.80 to - 0.28) measured at the period of cryptogenic stroke was significantly decreased in patients with AF occurrence compared to without. SROC analysis suggested an acceptable predictive efficiency of εR for AF occurrence (AUC = 0.799). For patients after cryptogenic stroke, GLS, εR, εCD, εCT and SRe were significantly decreased in AF occurrence compared with non-occurrence. But there was no value in left atrial reservoir strain rate (SRs) and contractile strain rate (SRa) for predicting AF.

How should I treat patients with subclinical atrial fibrillation and atrial high-rate episodes? Current evidence and clinical importance

Long-term and continuous ECG monitoring using cardiac implantable electronic devices and insertable cardiac monitors has improved the capability of detecting subclinical atrial fibrillation (AF) and atrial high-rate episodes. Previous studies demonstrated a high prevalence (more than 20%) in patients with cardiac implantable electronic devices or insertable cardiac monitors. Subclinical AF and atrial high-rate episodes are often suspected as the cause of prior or potential future ischemic stroke. However, the clinical significance is still uncertain, and the evidence is limited. This review aims to present and discuss the current evidence on the clinical impact of subclinical AF and atrial high-rate episodes. It focuses particularly on the association between the duration of the episodes and major clinical outcomes like thromboembolic events. As subclinical AF and atrial high-rate episodes are presumed to be associated with ischemic strokes, detection will be particularly important in patients with cryptogenic stroke and in high-risk patients for thromboembolism. In this context, it is also interesting whether there is a temporal relationship between the detection of subclinical AF and atrial high-rate episodes and the occurrence of thromboembolic events. In addition, the review will examine the question whether there is a need for a therapy with oral anticoagulation.

What to do with device-detected atrial high-rate episodes: Summary of the evidences

Cardiac implanted electronic devices (CIEDs), that perform atrial sensing via an atrial electrode, commonly detect self-terminating atrial arrhythmias. Nomenclature of these arrhythmias is defined as atrial high-rate episodes (AHREs) and subclinical atrial fibrillation (SCAF). We have provided a comprehensive summation of the trials regarding the incidence and adverse outcomes of AHREs. The reported incidence of AHRE varies considerably (approximately 10% to %70) between studies depending on the definition of AHRE, duration of follow-up and the clinical profile of the population. There is increasing evidence related with the association between AHREs' and stroke and/or systemic embolism. However, risk of stroke and/or systemic embolism seems to be less than the risk associated with clinical AF. There is still lack of sufficient evidence related with oral anticoagulation (OAC) in patients with AHRE to reduce thromboembolic risk. Although, the strongest association of OAC treatment with reduction in stroke has been reported to be observed among patients with device detected SCAF episodes of >24 hours; it is still questionable whether AHRE is a direct cause of thromboembolic event or just a marker of increased risk. Results of ongoing randomized clinical trials (NOAH-AFNET 6 and ARTESIA) will provide robust evidence on effect of OAC therapy on AHREs. This article is protected by copyright. All rights reserved.

Papel dos Níveis de Sódio na Fibrilação Atrial na Insuficiência Cardíaca: Jogador Ativo ou Bystander?

Fundamento

Objetivo

Métodos

Resultados

Conclusão

Impact of Peripheral Microvascular Endothelial Dysfunction on White Matter Hyperintensity

Background White matter hyperintensity (WMH), characterized by hyperintensities on T2-weighted fluid-attenuated inversion recovery brain magnetic resonance imaging, has been linked to an increased risk of ischemic stroke (IS). Endothelial dysfunction is an indicator of vascular dysfunction, predicting the risk of IS. This study aimed to investigate the association between endothelial dysfunction and regional WMH, and its impact on future risk of IS. Methods and Results We enrolled 219 patients (mean age, 53.1±14.1 years; 34.7% men) who underwent peripheral endothelial function assessment using reactive hyperemia peripheral arterial tonometry and brain magnetic resonance imaging without any history of IS. Volumetric WMH segmentation was automatically extrapolated using a validated automated digital tool. Total and juxtacortical WMH volume/intracranial volume (%) increased with aging and became more prominent in patients aged >50 years (n=131) than those aged ≤50 years (n=88) (total WMH: ≤50 years, Pearson r=0.24, P=0.03; >50 years, Pearson r=0.62, P<0.0001; juxtacortical WMH: ≤50 years, Pearson r=0.09, P=0.40; >50 years, Pearson r=0.55, P<0.0001). Reactive hyperemia peripheral arterial tonometry index was negatively associated with total and juxtacortical WMH volume/intracranial volume (%) in patients aged >50 years after adjustment for other covariates (reactive hyperemia peripheral arterial tonometry index, standardized β coefficient -0.17, P=0.04). Juxtacortical WMH volume/intracranial volume (%) was associated with an increased risk of IS during median follow-up of 6.5 years (hazard ratio, 1.47; 95% CI, 1.05-1.92; P=0.03). Conclusions Peripheral endothelial dysfunction is associated with an increased volume of juxtacortical WMH in patients aged >50 years, which is a potential marker to predict future risk of IS.

Usefulness of P-wave duration in patients with sick sinus syndrome as a predictor of atrial fibrillation

BACKGROUND

This study aimed to clarify P-wave duration (PWD) ability before pacemaker implantation to predict worsening atrial fibrillation (AF) burden after the procedure.

METHODS

We retrospectively investigated 75 patients who underwent permanent pacemaker implantation due to sick sinus syndrome (SSS) at Komaki City Hospital between January 2006 and May 2019. Worsening AF burden was defined as an increase in the number of AF episodes, each lasting ≥5.5 hours a day.

RESULTS

In the study population, 17 patients (23%) had worsening AF burden during the follow-up period. These patients had significantly longer PWD in lead Ⅱ (117.9 ± 19.9 ms vs 101.3 ± 20.0 ms, P = .002) than the patients without worsening AF burden. The best discriminative cutoff value for PWD in lead Ⅱ was 108 ms (sensitivity, 77%; specificity, 67%). In multivariate analysis, PWD in lead II ≥108 ms (hazard ratio, 5.395; 95% confidence interval, 1.352-21.523; P = .017) was an independent predictor of worsening AF burden. Patients with PWD in lead II <108 ms showed a significantly higher event-free rate against worsening AF burden than those with PWD in lead II ≥108 ms (81% vs 9%, P = .005).

CONCLUSIONS

Prolonged PWD before pacemaker implantation was the most important independent predictor of worsening AF burden after the procedure. In patients with SSS, prolonged PWD can be a useful marker for predicting worsening of AF burden after pacemaker implantation.

Atrial Fibrillation and Endothelial Dysfunction: A Potential Link?

Atrial fibrillation (AF) is the most common cardiac arrhythmia, and coronary atherosclerosis is the leading cause of death in the United States and worldwide. Endothelial dysfunction is the earliest clinically detectable form of atherosclerosis. Control of shared AF and coronary atherosclerosis risk factors improves both AF-free survival and vascular endothelial function. Decades of AF research have yielded fundamental insight into AF pathophysiology, but current pharmacological and catheter-based invasive AF therapies have limited long-term efficacy and substantial side effects, possibly because of incomplete understanding of underlying complex AF pathophysiology. We hereby discuss potential mechanistic links between endothelial dysfunction and AF (risk-factor-associated systemic inflammation and oxidative stress, myocardial ischemia, common gene variants, vascular shear stress, and fibroblast growth factor-23), explore a potential new vascular dimension to AF pathophysiology, highlight a growing body of evidence supporting an association between systemic vascular endothelial dysfunction, AF, and stroke, and discuss potential common effective therapies.

Burden of oral anticoagulation in embolic stroke of undetermined source without atrial fibrillation

Objective

Prevention of recurrent stroke in patients with embolic stroke of undetermined source (ESUS) is challenging. The advent of safer anticoagulation in the form of direct oral anticoagulants (DOACs) has prompted exploration of prophylactic anticoagulation for all ESUS patients, rather than anticoagulating just those with documented atrial fibrillation (AF). However, recent trials have failed to demonstrate a clinical benefit, while observing increased bleeding. We modeled the economic impact of anticoagulating ESUS patients without documented AF across multiple geographies.

Methods

CRYSTAL-AF trial data were used to assess ischaemic stroke event rates in ESUS patients confirmed AF-free after long-term monitoring. Anticipated bleeding event rates (including both minor and major bleeds) with aspirin, dabigatran 150 mg, and rivaroxaban 20 mg were sourced from published meta-analyses, whilst a 30% ischaemic stroke reduction for both DOACs was assumed. Cost data for clinical events and pharmaceuticals were collected from the local payer perspective.

Results

Compared with aspirin, dabigatran and rivaroxaban resulted in 17.9 and 29.9 additional bleeding events per 100 patients over a patient’s lifetime, respectively. Despite incorporating into our model the proposed 30% reduction in ischaemic stroke risk, both DOACs were cost-additive over patient lifetime, as the costs of bleeding events and pharmaceuticals outweighed cost savings associated with the reduction in ischaemic strokes. DOACs added £5953–£7018 per patient (UK), €6683–€7368 (Netherlands), €4933–€9378 (Spain), AUD$5353–6539 (Australia) and $26,768–$32,259 (US) of payer cost depending on the agent prescribed. Additionally, in the U.S. patient pharmacy co-payments ranged from $2468–$12,844 depending on agent and patient plan. In all settings, cost-savings could not be demonstrated even when the modelling assumed 100% protection from recurrent ischaemic strokes, due to the very low underlying risk of recurrent ischaemic stroke in this population (1.27 per 100 patient-years).

Conclusions

Anticoagulation of non-AF patients may cause excess bleeds and add substantial costs for uncertain benefits, suggesting a personalised approach to anticoagulation in ESUS patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-01967-x.

Atrial fibrillation and stroke: how much atrial fibrillation is enough to cause a stroke?

PURPOSE OF REVIEW

The association between atrial fibrillation and stroke is firmly established, and anticoagulation reduces stroke risk in patients with atrial fibrillation. However, the role of anticoagulation in very brief durations of atrial fibrillation (subclinical atrial fibrillation) is an area of controversy.

RECENT FINDINGS

Stroke risk increases alongside burden of atrial fibrillation. Ongoing trials will clarify if 24 h or less of atrial fibrillation on extended monitoring necessitates lifelong anticoagulation. Trials examining empiric anticoagulation for individuals with ESUS did not demonstrate benefit over antiplatelet agents. However, hypothesis-generating sub-analyses suggest that certain at-risk groups may benefit. Atrial cardiopathy is associated with subclinical atrial fibrillation and research examining anticoagulation after ESUS in this population is underway.

SUMMARY

Stroke risk increases alongside burden of ectopic atrial activity. However, this risk may in part be because of prothrombotic dysfunction associated with atrial cardiopathy in addition to the arrhythmia itself. The minimal amount of subclinical atrial fibrillation to warrant anticoagulation for stroke prevention, and how this may be modified by the total duration of monitoring, will be clarified by the results of ongoing clinical trials. Currently research will also help identify whether a select group of ESUS patients who have structural and electrophysiological markers of atrial cardiopathy warrant anticoagulation for secondary prevention.

Recurrent Stroke With Rivaroxaban Compared With Aspirin According to Predictors of Atrial Fibrillation: Secondary Analysis of the NAVIGATE ESUS Randomized Clinical Trial

Importance

The NAVIGATE ESUS randomized clinical trial found that 15 mg of rivaroxaban per day does not reduce stroke compared with aspirin in patients with embolic stroke of undetermined source (ESUS); however, it substantially reduces stroke risk in patients with atrial fibrillation (AF).

Objective

To analyze whether rivaroxaban is associated with a reduction of recurrent stroke among patients with ESUS who have an increased risk of AF.

Design, Setting, and Participants

Participants were stratified by predictors of AF, including left atrial diameter, frequency of premature atrial contractions, and HAVOC score, a validated scheme using clinical features. Treatment interactions with these predictors were assessed. Participants were enrolled between December 2014 and September 2017, and analysis began March 2018.

Intervention

Rivaroxaban treatment vs aspirin.

Main Outcomes and Measures

Risk of ischemic stroke.

Results

Among 7112 patients with a mean (SD) age of 67 (9.8) years, the mean (SD) HAVOC score was 2.6 (1.8), the mean (SD) left atrial diameter was 3.8 (1.4) cm (n = 4022), and the median (interquartile range) daily frequency of premature atrial contractions was 48 (13-222). Detection of AF during follow-up increased for each tertile of HAVOC score: 2.3% (score, 0-2), 3.0% (score, 3), and 5.8% (score, >3); however, neither tertiles of the HAVOC score nor premature atrial contractions frequency impacted the association of rivaroxaban with recurrent ischemic stroke (P for interaction = .67 and .96, respectively). Atrial fibrillation annual incidence increased for each tertile of left atrial diameter (2.0%, 3.6%, and 5.2%) and for each tertile of premature atrial contractions frequency (1.3%, 2.9%, and 7.0%). Among the predefined subgroup of patients with a left atrial diameter of more than 4.6 cm (9% of overall population), the risk of ischemic stroke was lower among the rivaroxaban group (1.7% per year) compared with the aspirin group (6.5% per year) (hazard ratio, 0.26; 95% CI, 0.07-0.94; P for interaction = .02).

Conclusions and Relevance

The HAVOC score, left atrial diameter, and premature atrial contraction frequency predicted subsequent clinical AF. Rivaroxaban was associated with a reduced risk of recurrent stroke among patients with ESUS and moderate or severe left atrial enlargement; however, this needs to be independently confirmed before influencing clinical practice.

Incremental Prognostic Impact of Peripheral Microvascular Endothelial Dysfunction on the Development of Ischemic Stroke

Background

Peripheral microvascular endothelial dysfunction (PMED) has been linked to an increased risk of cardiovascular events, but there is a lack of information characterizing the predictive value of PMED for future risk of ischemic stroke (IS).

Methods and Results

This retrospective observational cohort study enrolled 637 patients who underwent non‐invasive microvascular endothelial function assessment using reactive hyperemia peripheral arterial tonometry. Reactive hyperemia peripheral arterial tonometry index ≤2 was defined as PMED. Of 280 patients with PMED, 12 (4.3%) patients developed IS, compared with only 4 (1.1%) of 357 patients without PMED during a median follow‐up of 5.3 years. Patients with PMED had lower IS‐free survival compared with patients without PMED (log‐rank P=0.03). Cox proportional hazard ratio (HR) analyses showed that PMED predicted the incidence of IS, with a HR of 3.43, 95% CI, 1.10–10.63 (P=0.03); adjusted HR of 3.70, 95% CI, 1.18–11.59 (P=0.02) after adjusting for sex, smoking history, and atrial fibrillation; adjusted HR of 3.45, 95% CI, 1.11–10.72 (P=0.03) after adjusting for CHA₂DS₂‐VASc score; adjusted HR of 5.70, 95% CI, 1.40–23.29 (P=0.02) after adjusting for revised Framingham Stroke Risk Score. Reactive hyperemia peripheral arterial tonometry index improved discrimination of risk for IS after adding reactive hyperemia peripheral arterial tonometry index to CHA₂DS₂‐VASc score and revised Framingham Stroke Risk Score.

Conclusions

PMED was associated with a >3‐fold increased risk of IS. These findings underscore the concept of the systemic nature of endothelial dysfunction, which could act as a potential marker to predict future risk of IS.

Atrial premature activity detected after an ischaemic stroke unveils atrial myopathy

BACKGROUND

Recent publications suggest that left atrial (LA) myopathy is a potential source of thromboembolism, independent of atrial fibrillation.

AIMS

We sought to investigate whether the presence of atrial premature activity after an ischaemic stroke is associated with LA remodelling and dysfunction, and might be a surrogate marker of LA myopathy.

METHODS

After an ischaemic stroke or a transient ischaemic attack, patients without known atrial fibrillation or overt heart disease were included prospectively in the study. All patients had a standard workup, including ambulatory Holter electrocardiogram monitoring and transthoracic echocardiography. In some patients, transoesophageal echocardiography was also performed. Anatomical and functional LA remodelling were assessed using minimal and maximal volumes and LA emptying fraction in two-dimensional and three-dimensional echocardiography. Patients were separated into two groups according to the burden of atrial premature complexes (APCs), measured by Holter electrocardiography.

RESULTS

Among 148 eligible patients recruited from October 2015 to May 2016, 93 were included in the group with non-frequent APCs (nf-APC:<100 APCs/24hours) and 43 in the group with frequent APCs (f-APC:>100 APCs/24hours). Twelve patients had paroxysmal atrial fibrillation, and were not included in the statistical analysis. Maximal and minimal indexed LA volumes were significantly higher in the f-APC group than in the nf-APC group (P<0.01). LA emptying fraction was worse in the f-APC group than in the nf-APC group. In addition, LA appendage emptying velocity was impaired in the f-APC group, and was correlated with LA remodelling variables, especially LA emptying fraction (r=0.621).

CONCLUSIONS

After an ischaemic stroke or a transient ischaemic attack, excessive APCs are associated with LA remodelling. Thus, LA dilatation and dysfunction reflect early LA myopathy, which might itself be responsible for cardioembolic stroke.

Thromboembolic events around the time of cardioversion for atrial fibrillation in patients receiving antiplatelet treatment in the ACTIVE trials

Aims

It is unknown whether cardioversion of atrial fibrillation causes thromboembolic events or is a risk marker. To assess causality, we examined the temporal pattern of thromboembolism in patients having cardioversion.

Methods and results

We studied patients randomized to aspirin or aspirin plus clopidogrel in the ACTIVE trials, comparing the thromboembolic rate in the peri-cardioversion period (30 days before until 30 days after) to the rate during follow-up, remote from cardioversion. Among 962 patients, the 30-day thromboembolic rate remote from cardioversion was 0.16%; while it was 0.73% in the peri-cardioversion period [hazard ratio (HR) 4.1, 95% confidence interval (CI) 2.1–7.9]. The 30-day thromboembolic rates in the periods immediately before and after cardioversion were 0.47% and 0.96%, respectively (HR 2.2, 95% CI 0.7–7.1). Heart failure (HF) hospitalization increased in the peri-cardioversion period (HR 11.5, 95% CI 6.8–19.4). Compared to baseline, the thromboembolic rate in the 30 days following cardioversion was increased both in patients who received oral anticoagulation or a transoesophageal echocardiogram prior to cardioversion (HR 7.9, 95% CI 2.8–22.4) and in those who did not (HR 4.8, 95% CI 1.6–14.9) (interaction P = 0.2); the risk was also increased with successful (HR 4.5; 95% CI 2.0–10.5) and unsuccessful (HR 10.2; 95% CI 2.3–44.9) cardioversion.

Conclusions

Thromboembolic risk increased in the 30 days before cardioversion and persisted until 30 days post-cardioversion, in a pattern similar to HF hospitalization. These data suggest that the increased thromboembolic risk around the time of cardioversion may not be entirely causal, but confounded by the overall clinical deterioration of patients requiring cardioversion.

Complexities in the Atrial Fibrillation-Stroke Relationship: Improving Comprehension of Temporal Discordance, Magnitude Synergism, and Subclinical Atrial Fibrillation -- Three Sources of Consternation for Physicians Who Care for Patients with Atrial Fibrillation

That clinically-documented atrial fibrillation (AF) in association with a variety of elevated clinical/laboratory risk markers is associated with an increased risk of stroke is well known -- regardless of whether the AF is paroxysmal, persistent, or permanent. Moreover, data is accumulating to suggest that the absolute rate of stroke should be expectedly higher with a greater burden of AF and greater degree of comorbid contributors. Relatedly, stroke prevention with chronic oral anticoagulation (OAC) is recommended for AF patients with appropriate risk markers by all major medical, cardiologic, and surgical guideline-writing organizations. However, at least two major clinical concerns about the above AF-stroke statements remain. First, if AF is related to stroke, why then is there not a consistent temporal relationship between a stroke and AF? Second, is there importance to and what should we do about device-detected AF (so-called subclinical AF [SCAF]) in the absence of clinically-recognized AF? This paper is designed to enhance the understanding of these issues and reduce the consternation of physicians who care for patients with AF with respect to them.