Ejection fraction and outcomes in patients with atrial fibrillation and heart failure: the Loire Valley Atrial Fibrillation Project

Both HFpEF and HFmrEF should be included in calculating CHA2DS2-VASc score: A Taiwanese longitudinal cohort

BACKGROUND

Congestive heart failure (CHF) as a risk of stroke in patients with atrial fibrillation (AF) mainly referred to patients with left ventricular systolic dysfunction. Whether this should include patients with preserved ejection fraction is debatable.

OBJECTIVE

The study aimed to investigate the variation in stroke risk of AF patients with heart failure with preserved ejection fraction (HFpEF), heart failure with mid-range ejection fraction (HFmrEF), and heart failure with reduced ejection fraction (HFrEF) for enhancing risk assessment and subsequent management strategies.

METHODS

In a longitudinal study using the National Taiwan University Hospital integrated Medical Database, 8358 patients with AF were observed for 10 years (mean follow-up, 3.76 years). The study evaluated the risk of ischemic stroke in patients with differing ejection fractions and CHA2DS2-VASc score, further using Cox models adjusted for risk factors of AF-related stroke.

RESULTS

Patients with HFpEF and HFmrEF had a higher mean CHA2DS2-VASc score compared with patients with HFrEF (4.30 ± 1.729 vs 4.15 ± 1.736 vs 3.73 ± 1.712; P < .001) and higher risk of stroke during follow-up (hazard ratio [HR], 1.40 [1.161-1.688; P < .001] for HFmrEF; HR, 1.184 [1.075-1.303; P = .001] for HFpEF vs no CHF) after multivariate adjustment). In patients with lower CHA2DS2-VASc score (0-4), presence of any type of CHF increased ischemic stroke risk (HFrEF HR, 1.568 [1.189-2.068; P = .001]; HFmrEF HR, 1.890 [1.372-2.603; P < .001]; HFpEF HR, 1.800 [1.526-2.123; P < .001] vs no CHF).

CONCLUSION

After multivariate adjustment, HFpEF and HFmrEF showed a similar risk of stroke in AF patients. Therefore, it is important to extend the criteria for C in the CHA2DS2-VASc score to include patients with HFpEF and HFmrEF. In patients with fewer concomitant stroke risk factors, the presence of any subtype of CHF increases risk for ischemic stroke.

Interaction of heart failure and stroke: A clinical consensus statement of the ESC Council on Stroke, the Heart Failure Association (HFA) and the ESC Working Group on Thrombosis

Heart failure (HF) is a major disease in our society that often presents with multiple comorbidities with mutual interaction and aggravation. The comorbidity of HF and stroke is a high risk condition that requires particular attention to ensure early detection of complications, efficient diagnostic workup, close monitoring, and consequent treatment of the patient. The bi-directional interaction between the heart and the brain is inherent in the pathophysiology of HF where HF may be causal for acute cerebral injury, and - in turn - acute cerebral injury may induce or aggravate HF via imbalanced neural and neurovegetative control of cardiovascular regulation. The present document represents the consensus view of the ESC Council on Stroke, the Heart Failure Association and the ESC Working Group on Thrombosis to summarize current insights on pathophysiological interactions of the heart and the brain in the comorbidity of HF and stroke. Principal aspects of diagnostic workup, pathophysiological mechanisms, complications, clinical management in acute conditions and in long-term care of patients with the comorbidity are presented and state-of-the-art clinical management and current evidence from clinical trials is discussed. Beside the physicians perspective, also the patients values and preferences are taken into account. Interdisciplinary cooperation of cardiologists, stroke specialists, other specialists and primary care physicians is pivotal to ensure optimal treatment in acute events and in continued long-term treatment of these patients. Key consensus statements are presented in a concise overview on mechanistic insights, diagnostic workup, prevention and treatment to inform clinical acute and continued care of patients with the comorbidity of HF and stroke.

Optimization of guideline-directed medical treatment for heart failure patients with reduced ejection fraction

With the increasing number of medications demonstrating mortality benefits in heart failure with reduced ejection fraction (HFrEF), the pharmacological treatment of HFrEF is entering a new phase. To enhance outcomes in heart failure patients through medical treatment, the choice of appropriate medications and simultaneous and rapid uptitration are critical. However, there are several challenges encountered during this medication uptitration, including issues like hypotension, fatigue, worsening renal function, and hyperkalemia. This paper addresses strategies for effectively managing these challenges to successfully reach the maximum tolerated dose in patients. Additionally, it will discuss the management of comorbidities often associated with heart failure, the importance of exercise and rehabilitation, and the significance of proper nutrition intake, in addition to guideline-directed medical therapy.

Heart failure in patients with atrial fibrillation: Insights from Polish part of the EORP-AF general long-term registry

AIMS

This study aimed to determine the impact of heart failure (HF) on clinical outcomes in patients with atrial fibrillation (AF).

METHODS AND RESULTS

We analysed data from Polish participants of the EURObservational Research Programme-AF General Long-Term Registry. The primary endpoint was all-cause death, and the secondary endpoints included hospital readmissions, cardiovascular (CV) interventions, thromboembolic and haemorrhagic events, rhythm control interventions, and other CV or non-CV diseases development during one-year follow up. Overall, 688 patients with available data on HF were included into analysis; 51% (n = 351) had HF; of these 48% (n = 168) had reduced ejection fraction (HFrEF), 22% (n = 77) mid-range EF (HFmrEF), and 30% (n = 106) preserved EF (HFpEF). Compared with patients without HF, those with HF had higher mortality rate (aHR 5.61; 95% CI 1.94-16.22, P < 0.01). Patients with HF (vs. without HF) had more often CV interventions (10% vs. 5.4%, P = 0.046) and events (14% vs. 7.1%, P = 0.02), and had less often atrial arrhythmia-related hospital admissions (6.8% vs. 15%, P < 0.01). Over follow-up, patients with HFmrEF and HFpEF had similar mortality rate versus HFrEF (aHR 0.45, 95% CI 0.13-1.57, P = 0.45 for HFmrEF and aHR 0.54, 95% CI 0.20-1.48, P = 0.54 for HFpEF). Mortality rate was similar among rhythm versus rate control group (aHR 0.34; 95% CI 0.10-1.16; P = 0.34).

CONCLUSIONS

AF patients with HF have greater mortality rate and more CV interventions/events. No statistically significant difference in long-term outcomes between patients with HFrEF, HFmrEF, and HFpEF highlights the need to develop therapeutic strategies targeting functional status and survival for patients with HF and AF.

Breaking the Cycle of Heart Failure With Preserved Ejection Fraction and Atrial Fibrillation

Heart failure with preserved ejection fraction (HFpEF) and AF are two common cardiovascular conditions that are inextricably linked to each other's development and progression, often in multimorbid patients. Current management is often directed to specific components of each disease without considering their joint impact on diagnosis, treatment and prognosis. The result for patients is suboptimal on all three levels, restricting clinicians from preventing major adverse events, including death, which occurs in 20% of patients at 2 years and in 45% at 4 years. New trial evidence and reanalysis of prior trials are providing a glimmer of hope that adverse outcomes can be reduced in those with concurrent HFpEF and AF. This will require a restructuring of care to integrate heart failure and AF teams, alongside those that manage comorbidities. Parallel commencement and non-sequential uptitration of therapeutics across different domains will be vital to ensure that all patients benefit at a personal level, based on their own needs and priorities.

Treatment strategies for patients with atrial fibrillation and chronic heart failure

Atrial fibrillation (AF) is associated with significant morbidity and mortality and may lead to the development of chronic heart failure (CHF). Each condition predisposes to the other, requiring a careful choice of the treatment strategy. This article is devoted to the prevalence and prognostic implications of both diseases. The article presents data from meta-analyzes related to the management of this group of patients. The aspects of rhythm control strategy in AF and concomitant CHF are described according to the recent studies and clinical guidelines. The features of anticoagulant therapy in patients with AF and CHF are outlined. Much attention is given to the importance of the safety profile of the anticoagulant therapy in terms of the bleeding risk in patients with concomitant AF and CHF.

Meta-Analysis of Catheter Ablation versus Medical Therapy for Heart Failure Complicated with Atrial Fibrillation

Objective

To compare the efficacy of catheter ablation and medical therapy in patients with heart failure and atrial fibrillation.

Methods

We searched randomized controlled trials comparing catheter ablation versus medical therapy for heart failure and atrial fibrillation through PubMed, MEDLINE, Embase, Cochrane Clinical Trials Database, Web of Science, and China National Knowledge Infrastructure. Articles were investigated for their methodological quality using the Cochrane Collaboration risk of the bias assessment tool. Forest plots, funnel plots, and sensitivity analysis were also performed on the included articles. Results were expressed as risk ratio (RR) and mean difference (MD) with 95% confidence intervals.

Results

Nine (9) studies were included in this study with 1131 patients. Meta-analysis showed a reduction in all-cause mortality from catheter ablation compared with medical therapy (RR = 0.53, 95% CI = 0.37 to 0.76; P=0.0007) and improved left ventricular ejection fraction (LVEF) (MD = 6.45, 95% CI = 3.49 to 9.41; P < 0.0001), 6-minute walking time (6MWT) (MD = 28.32, 95% CI = 17.77 to 38.87; P < 0.0001), and Minnesota Living with Heart Failure Questionnaire (MLHFQ) score (MD = 8.19, 95% CI = 0.30 to 16.08; P=0.04).

Conclusion

Catheter ablation had a better improvement than medical treatment in left ventricular ejection fraction, cardiac function, and exercise ability for atrial fibrillation and heart failure patients.

Perceptions and knowledge gaps on CHA2DS2-VASc score components: a joint survey of Chinese clinicians and clinical pharmacists

BACKGROUND

The CHA₂DS₂-VASc score is a guideline-recommended stroke risk stratification scheme for patients with atrial fibrillation (AF). Accurately calculating the CHA₂DS₂-VASc score and recognizing the stroke risk in AF patients is the foundation of optimal anticoagulation therapy. This survey aims to obtain a comprehensive understanding of perceptions and knowledge gaps on CHA₂DS₂-VASc scores among Chinese medical professionals for future education programs.

METHODS

A cross-sectional survey was conducted among clinicians, including cardiologists, neurologists, emergency physicians (EPs), general practitioners (GPs) and clinical pharmacists (CPs) using a self-administered questionnaire on the Chinese mainland. The survey contained 21 questions in combination with single-choice questions, multiple-choice questions, and an open-ended question, which was distributed online via e-mail or social media.

RESULTS

A total of 562 participants (40.9% cardiologists, 19.2% neurologists, 8.5% EPs, 10.3% GPs, and 21.0% CPs) completed the survey. Most respondents across all specialties reported skills requiring improvements in the CHA₂DS₂-VASc score. In general, cardiologists, neurologists, and CPs had a relatively better understanding than GPs and EPs about the application of CHA₂DS₂-VASc score. Considering 'H' and 'D' components, more than 90% of respondents chose the correct answer in single-choice questions, whereas the correctness rate declined concerning detailed scoring criteria. Regarding 'C,' 'A₂,' 'S₂,' and 'V' components, partly correct answers were commonly observed in most multiple-choice questions. The majority of cardiologists believed themselves to be very familiar or at least familiar with the score and its components, while around 70% of EPs and GPs felt relatively unfamiliar with the CHA₂DS₂-VASc score. Mobile apps, AF guidelines and notebooks/handbooks were popular referencing scoring tools for respondents.

CONCLUSIONS

Chinese medical professionals, especially EPs and GPs, revealed a lack of knowledge and insufficient skills for CHA₂DS₂-VASc scores and their components. Improvements in the awareness of the CHA₂DS₂-VASc score and its detailed scoring criteria are urgently needed for Chinese medical professionals. Therefore, education programs concerning the introduction of stroke risk evaluation for AF patients and the development of referencing scoring tools are necessary.

Rhythm Control in Patients with Heart Failure with Preserved Ejection Fraction: A Meta-Analysis

Background The presence of atrial fibrillation (AF) in patients with heart failure with preserved ejection fraction (HFpEF) dramatically increases higher morbidity and mortality. Recent studies have suggested that early rhythm control may alleviate the burden of poor outcomes. Currently, there remain limited data on whether rhythm or rate control has better efficacy. This study sought to compare both strategies in HFpEF patients with AF. Methods Databases were searched throughout 2020. Studies that reported cardiovascular outcomes amongst HFpEF patients with AF who received either rhythm or rate control were included. Estimates of the effects from the individual studies were extracted and combined using random-effects, a generic inverse variance method of DerSimonian and Laird. Results Five observational studies were included in the analysis, consisting of 16,953 patients, 13.8% of whom were receiving rhythm control. In comparison with rate control, rhythm control was associated with decreased overall mortality rates (pooled RR 0.85, 95% CI 0.75–0.95, with I² = 0%, p value = 0.009). Conclusions In HFpEF patients with AF, rhythm control was associated with lower mortality, compared to rate control. Further studies are warranted to validate our observation.

Stroke and Bleeding Risk Assessment in Atrial Fibrillation: Where Are We Now?

Stroke prevention with oral anticoagulants (OACs) is the cornerstone for the management of patients with atrial fibrillation (AF). It is crucial to assess the stroke and bleeding risks of individual AF patients to make appropriate decisions for OAC use and achieve optimal patient care. In this review, we provided an overview on the correct use of CHA₂DS₂-VASc and HAS-BLED scores, and update important revisions about the definitions of some of the CHA₂DS₂-VASc components. Also, data about the biomarkers and potential roles of AF duration and left atrial functions in the prediction of stroke in AF were also discussed.

Most important international guidelines recommend the use of CHA₂DS₂-VASc and HAS-BLED scores for stroke and bleeding risk assessments in atrial fibrillation (AF) patients, respectively. The 2020 AF guidelines of European Society of Cardiology have revised the definition of “C: congestive heart failure (HF)” component, and now patients with either HF with reduced ejection fraction or preserved ejection fraction should be assigned 1 point. Hypertrophic cardiomyopathy was also included. Besides, the revised “V: vascular diseases” component included both prior myocardial infarction and “angiographically significant coronary artery disease”. It is important to understand that the stroke and bleeding risks of AF patients were not static and should be re-assessed regularly. A high HAS-BLED score itself should not be the only reason to withhold or discontinue oral anticoagulants, but remind physicians for the corrections of modifiable bleeding risk factors and more regular follow up. In the future, the AF duration and left atrial function may play an important role for personalized evaluation of individual stroke risk while more studies are necessary.

Heart Failure and Atrial Fibrillation, Like Fire and Fury

Heart failure and atrial fibrillation are 2 common cardiovascular disorders that frequently complicate one another and exert a significant detrimental effect on cardiovascular health and well-being. Both heart failure and atrial fibrillation continue to increase in prevalence as the risk factors underlying each condition become more common. This review encompasses what is currently known about the epidemiology and pathophysiology of these comorbidities along with incorporation of landmark trials that have contributed to current guidelines. The focus is on clinically relevant considerations, including the contribution of inflammation in the pathophysiology of atrial fibrillation and heart failure. We explore the emerging role of catheter ablation relative to medical therapy in the management of heart failure with reduced ejection fraction, along with indications for biventricular pacing modalities in cardiac resynchronization therapy. We discuss current guideline-directed therapies and how practice models and national recommendations will likely change based on the most recent randomized controlled trials.

The Role of Antithrombotic Therapy in Heart Failure

Heart failure is a major contributor to global morbidity and mortality burden affecting approximately 1-2% of adults in developed countries, mounting to over 10% in individuals aged >70 years old. Heart failure is characterized by a prothrombotic state and increased rates of stroke and thromboembolism have been reported in heart failure patients compared with the general population. However, the impact of antithrombotic therapy on heart failure remains controversial. Administration of antiplatelet or anticoagulant therapy is the obvious (and well-established) choice in heart failure patients with cardiovascular comorbidity that necessitates their use, such as coronary artery disease or atrial fibrillation. In contrast, antithrombotic therapy has not demonstrated any clear benefit when administered for heart failure per se, i.e. with heart failure being the sole indication. Randomized studies have reported decreased stroke rates with warfarin use in patients with heart failure with reduced left ventricular ejection fraction, but at the expense of excessive bleeding. Non-vitamin K oral anticoagulants have shown a better safety profile in heart failure patients with atrial fibrillation compared with warfarin, however, current evidence about their role in heart failure with sinus rhythm is inconclusive and further research is needed. In the present review, we discuss the role of antithrombotic therapy in heart failure (beyond coronary artery disease), aiming to summarize evidence regarding the thrombotic risk and the role of antiplatelet and anticoagulant agents in patients with heart failure.

Impact of atrial fibrillation in patients with heart failure and reduced, mid-range or preserved ejection fraction

Objective

To determine the prognostic value of atrial fibrillation (AF) in patients with heart failure (HF) and preserved, mid-range or reduced ejection fraction (EF).

Methods

Patients hospitalised for acute HF were enrolled in the Korean Acute Heart Failure registry, a prospective, observational, multicentre cohort study, between March 2011 and February 2014. HF types were defined as reduced EF (HFrEF, LVEF <40%), mid-range EF (HFmrEF, LVEF 40%–49%) or preserved EF (HFpEF, LVEF ≥50%).

Results

Of 5414 patients enrolled, HFrEF, HFmrEF and HFpEF were seen in 3182 (58.8%), 875 (16.2%) and 1357 (25.1%) patients, respectively. The prevalence of AF significantly increased with increasing EF (HFrEF 28.9%, HFmrEF 39.8%, HFpEF 45.2%; p for trend <0.001). During follow-up (median, 4.03 years; IQR, 1.39–5.58 years), 2806 (51.8%) patients died. The adjusted HR of AF for all-cause death was 1.06 (0.93–1.21) in the HFrEF, 1.10 (0.87–1.39) in the HFmrEF and 1.22 (1.02–1.46) in the HFpEF groups. The HR for the composite of all-cause death or readmission was 0.97 (0.87–1.07), 1.14 (0.93–1.38) and 1.03 (0.88–1.19) in the HFrEF, HFmrEF and HFpEF groups, respectively, and the HR for stroke was 1.53 (1.03–2.29), 1.04 (0.57–1.91) and 1.90 (1.13–3.20), respectively. Similar results were observed after propensity score matching analysis.

Conclusions

AF was more common with increasing EF. AF was seen to be associated with increased mortality only in patients with HFpEF and was associated with an increased risk of stroke in patients with HFrEF or HFpEF.

Trial registration number

NCT01389843

Atrial Fibrillation Risk and Discrimination of Cardioembolic From Noncardioembolic Stroke

Background and Purpose- Classification of stroke as cardioembolic in etiology can be challenging, particularly since the predominant cause, atrial fibrillation (AF), may not be present at the time of stroke. Efficient tools that discriminate cardioembolic from noncardioembolic strokes may improve care as anticoagulation is frequently indicated after cardioembolism. We sought to assess and quantify the discriminative power of AF risk as a classifier for cardioembolism in a real-world population of patients with acute ischemic stroke. Methods- We performed a cross-sectional analysis of a multi-institutional sample of patients with acute ischemic stroke. We systematically adjudicated stroke subtype and examined associations between AF risk using CHA₂DS₂-VASc, Cohorts for Heart and Aging Research in Genomic Epidemiology-AF score, and the recently developed Electronic Health Record-Based AF score, and cardioembolic stroke using logistic regression. We compared the ability of AF risk to discriminate cardioembolism by calculating C statistics and sensitivity/specificity cutoffs for cardioembolic stroke. Results- Of 1431 individuals with ischemic stroke (age, 65±15; 40% women), 323 (22.6%) had cardioembolism. AF risk was significantly associated with cardioembolism (CHA₂DS₂-VASc: odds ratio [OR] per SD, 1.69 [95% CI, 1.49-1.93]; Cohorts for Heart and Aging Research in Genomic Epidemiology-AF score: OR, 2.22 [95% CI, 1.90-2.60]; electronic Health Record-Based AF: OR, 2.55 [95% CI, 2.16-3.04]). Discrimination was greater for Cohorts for Heart and Aging Research in Genomic Epidemiology-AF score (C index, 0.695 [95% CI, 0.663-0.726]) and Electronic Health Record-Based AF score (0.713 [95% CI, 0.681-0.744]) versus CHA₂DS₂-VASc (C index, 0.651 [95% CI, 0.619-0.683]). Examination of AF scores across a range of thresholds indicated that AF risk may facilitate identification of individuals at low likelihood of cardioembolism (eg, negative likelihood ratios for Electronic Health Record-Based AF score ranged 0.31-0.10 at sensitivity thresholds 0.90-0.99). Conclusions- AF risk scores associate with cardioembolic stroke and exhibit moderate discrimination. Utilization of AF risk scores at the time of stroke may be most useful for identifying individuals at low probability of cardioembolism. Future analyses are warranted to assess whether stroke subtype classification can be enhanced to improve outcomes in undifferentiated stroke.

Use of Cardiac Computed Tomography and Magnetic Resonance Imaging in Case Management of Atrial Fibrillation with Catheter Ablation

Atrial fibrillation (AF) is the most common arrhythmia associated with the risk of morbidity and mortality in clinical patients. AF is considered as an arrhythmia type that develops and progresses through close connection with cardiac structural arrhythmogenic substrates. Since the introduction of catheter ablation-mediated electrical isolation of arrhythmogenic substrates, cardiac imaging indicates improved treatment outcome and prognosis with appropriate candidate selection, ablation catheter guidance, and post-ablation follow-up. Currently, cardiac computed tomography (CCT) and cardiovascular magnetic resonance (CMR) imaging are essential in the case management of AF at both pre-and post-procedural stages of catheter ablation. In this review, we discuss the roles and technical considerations of CCT and CMR imaging in the management of patients with AF undergoing catheter ablation.

Stroke and Systemic Embolism and Other Adverse Outcomes of Heart Failure With Preserved and Reduced Ejection Fraction in Patients With Atrial Fibrillation (from the COmparison study of Drugs for symptom control and complication prEvention of Atrial Fibrillation [CODE-AF])

It is unknown whether heart failure (HF) with preserved ejection fraction (HFpEF) and HF with reduced ejection fraction (HFrEF) carry a similar risk of stroke or systemic embolism (SE) and other outcomes in patients with nonvalvular atrial fibrillation (AF). A prospective, multicenter outpatient registry with echocardiographic data which enrolled 10,589 patients from June 2016 to May 2019 was analyzed. In this registry, 935 (8.8%) patients had HF, and the proportions of patients with HFpEF and HFrEF were 43.2% and 56.8%, respectively. During follow-up over 1.33 years, 11 (2.07 per 100 person-years [PYR]) and 5 (0.76 per 100 PYR) patients had stroke/SE in the HFpEF and HFrEF groups, respectively, whereas 102 patients (0.84 per 100 PYR) had these sequelae in the no-HF group. The HFpEF group had a significantly higher cumulative incidence of stroke/SE (p = 0.004) and risk of stroke/SE (adjusted hazard ratio [HR] 2.23, 95% confidence interval [CI] 1.19 to 4.18) than the no-HF group. The risk of stroke/SE in the HFpEF group compared with that in the no-HF group was consistently increased even in patients on oral anticoagulation therapy (adjusted HR 2.55, 95% CI 1.31 to 4.96). There was a correlation between larger left atrial size and risk of stroke/SE (adjusted HR 1.53, 95% CI 1.03 to 2.29), but not between reduced left ventricular ejection fraction and this risk. In conclusion, these results suggest that strict oral anticoagulation therapy helps reduce the risk of stroke/SE in patients with nonvalvular AF and HFpEF, especially in those with a larger left atrial size.

Impact of Heart Failure Type on Thromboembolic and Bleeding Risk in Patients With Atrial Fibrillation on Oral Anticoagulation

Heart failure (HF) increases stroke risk in atrial fibrillation (AF) patients. Differential impact of HF category on thromboembolic and bleeding risk in AF patients on oral anticoagulation (OAC) is unknown. We used Medicare data for beneficiaries with new AF diagnosed between 2011 and 2013 to identify patients with HF with reduced ejection fraction (HFrEF), HF with preserved ejection fraction (HFpEF), and no HF. The primary endpoint of admission for ischemic stroke was evaluated using Cox proportional hazards regression models that controlled for patient demographics, comorbidities (including CHA₂DS₂-VASc and HASBLED scores), and OAC use as a time-dependent covariate. Secondary endpoints included all-cause mortality, admissions for gastrointestinal bleeding (GIB), intracranial hemorrhage (ICH), acute myocardial infarction (AMI), or HF. The 3groups included 47840, 32360, and 718392 patients respectively. Patients with HFrEF and HFpEF had higher comorbidity burden, CHA₂DS₂-VASc and HASBLED scores compared with patients without HF. In multivariable analysis adjusting for patient comorbidities and OAC, HFrEF and HFpEF were associated with higher risk of ischemic stroke, HF and AMI compared with no HF. HFrEF was associated with higher all-cause mortality and HF-hospitalization risk compared with HFpEF. In conclusion, in AF patients, HFrEF and HFpEF are both associated with higher risk of ischemic stroke, HF and AMI admissions, even after adjusting for OAC use, compared with patients without HF.

Heart Failure and Stroke

PURPOSE

Ischemic stroke significantly contributes to morbidity and mortality in heart failure (HF). The risk of stroke increases significantly, with coexisting atrial fibrillation (AF). An aggravating factor could be asymptomatic paroxysms of AF (so-called silent AF), and therefore, the risk stratification in these patients remains difficult. This review provides an overview of stroke risk in HF, its risk stratification, and stroke prevention in these patients.

RECENT FINDINGS

Stroke risk stratification in HF patients remains an important issue. Recently, the CHA₂DS₂-VASc score, originally developed to predict stroke risk in AF patients, had been reported to be a predictive for strokes in HF patients regardless of AF being present. Furthermore, there are several independent risk factors (e.g., hypertension, diabetes mellitus, prior stroke) described. Based on the current evidence, HF should be considered as an independent risk factor for stroke. The CHA₂DS₂-VASc score might be useful to predict stroke risk in HF patients with or without AF in clinical routine. However, there is only a recommendation for the oral anticoagulation use in patients with concomitant HF and AF, while in patients with HF and no AF, individualized risk stratification is preferred. Current guidelines recommend to prefer non-vitamin Kantagonist anticoagulants over warfarin.

Biomarkers Associated with Stroke Risk in Atrial Fibrillation

Background:

Atrial fibrillation (AF) is associated with an increased risk of cardioembolic stroke. The risk of cardioembolism is not adequately reduced with the administration of oral anticoagulants, since a number of patients continue to experience thromboembolic events despite receiving treatment. Therefore, identification of a circulating biomarker to identify these high-risk patients would be clinically beneficial.

Objective:

In the present article, we aim to review the available data regarding use of biomarkers to predict cardioembolic stroke in patients with AF.

Methods:

We performed a thorough search of the literature in order to analyze the biomarkers identified thus far and critically evaluate their clinical significance.

Results:

A number of biomarkers have been proposed to predict cardioembolic stroke in patients with AF. Some of them are already used in the clinical practice, such as d-dimers, troponins and brain natriuretic peptide. Novel biomarkers, such as the inflammatory growth differentiation factor-15, appear to be promising, while the role of micro-RNAs and genetics appear to be useful as well. Even though these biomarkers are associated with an increased risk for thromboembolism, they cannot accurately predict future events. In light of this, the use of a scoring system, that would incorporate both circulating biomarkers and clinical factors, might be more useful.

Conclusions:

Recent research has disclosed several biomarkers as potential predictors of cardioembolic stroke in patients with AF. However, further research is required to establish a multifactorial scoring system that will identify patients at high-risk of thromboembolism, who would benefit from more intensive treatment and monitoring.

Stroke risk stratification in atrial fibrillation: a review of common risk factors

Atrial Fibrillation (AF) has become a major global health concern being the most common sustained arrhythmia in clinical practice. Risk factors for AF include congestive heart failure, hypertension, increasing age and diabetes. Many of these factors also increase the risk for thromboembolism and ischemic stroke in AF patients. Great efforts have been made from the latter part of the 20th century towards developing an ideal stroke risk stratification tool in AF with the aim of reducing the incidence of stroke in AF patients and the limiting unnecessary use of thromboprophylaxis. The thromboembolic risks posed by AF with valvular heart disease are an important subgroup that contributes to a significant proportion of stroke in AF patients globally. We review the evolution of stroke risk stratification and summarize the guidelines for stroke prevention in non-valvular AF as well as AF with valvular heart disease, and the most recent recommendations on stroke prevention in AF patients. Abbreviations: AF: Atrial Fibrillation; ACS: Acute Coronary Syndrome; CAD: Coronary Artery Disease; CCF: Congestive Cardiac Failure; DM: Diabetes Mellitus; EHRA: Evaluated Heartvalves, Rheumatic or Artificial; ICH: Intracranial Hemorrhage; NOACs: Novel Oral Anticoagulants; OAC: Oral Anticoagulants; PAD: Peripheral Arterial Disease ; TIA: Transient Ischemic Attack; VHD: Valvular Heart Disease.

Anticoagulation in atrial fibrillation with heart failure

Heart failure (HF) and atrial fibrillation (AF) frequently coexist, and they can beget one another due to similar factors and shared pathophysiology. These pathophysiologic changes promote the episodes of AF, while they in turn predispose to the exacerbation of HF. In this review, we will discuss pathophysiological mechanisms shared by AF and HF. Patients with concomitant HF and AF are at a particularly high risk of thromboembolism, which contribute to even worse symptoms and poorer prognosis. Vitamin K antagonists (VKA) (warfarin) were the traditional medication in AF patients for the prevention of stroke, whereas the advance of novel non-VKA oral anticoagulants (NOACs) (dabigatran, apixaban, rivaroxaban, and edoxaban) is challenging these standard prescriptions. NOACs' potential advantages over warfarin, including fixed dosing regimens, wide therapeutic window, and more sustained anticoagulant response, promote clinicians to consider these novel agents in the first place. However, some data suggested patients with AF and HF may receive different therapeutic response than those with AF alone in anticoagulant treatment. Accordingly, we aim to assess the potential role of oral anticoagulants, especially NOACs, in the management of patients with concomitant AF and HF.

How do aging and comorbidities impact risk of ischemic stroke in patients with atrial fibrillation

Stroke is a notorious complication in patients with atrial fibrillation (AF) and risk stratification is pivotal for stroke prevention strategy. The risk of AF-related stroke is a mixture of complex interaction between increasing age and important comorbidities. Therefore, this article aims to provide a comprehensive review on these important risk factors of stroke in AF patients, mainly focusing on the component of CHA₂DS₂-VASc score, as well as some other potential risk factors.

Validation of Conventional Thromboembolic Risk Factors in a Korean Atrial Fibrillation Population - Suggestion for a Novel Scoring System, CHA2DS2-VAK

BACKGROUND

There is little evidence that focuses on the ethnic variability of clinical risk factors for thromboembolism (TE) in atrial fibrillation (AF). We aimed to investigate the effect of each traditional risk factor in the Korean AF population. Methods and Results: Medical records of 12,876 consecutive patients (aged >18 years) newly diagnosed and followed up with non-valvular AF from 2000 to 2013 were reviewed. TE events, including ischemic stroke and systemic embolism, were investigated for risk factor validation. Among the total of 12,876 patients, 1,390 (10.8%) had TE events. In univariate/multivariate analysis adjusting for clinical factors and antithrombotic medications, traditional risk factors included in the CHA₂DS₂-VASc scheme showed statistical significance, except for female sex, which was not a predictor of events. Additionally, chronic kidney disease (CKD; hazard ratio 1.62, P<0.001) was shown to be an independent predictor of TE events. Based on the analysis, we developed a novel stratification system, CHA₂DS₂-VAK, omitting the female sex category and adding CKD. The new scoring system showed greater discrimination in event rates between score 0 and 1 patients.

CONCLUSIONS

Female sex was not associated with TE events in a Korean non-valvular AF population. The novel CHA₂DS₂-VAK scoring system, with substitution of CKD for female sex, might be more appropriate for the Korean population.

Isolation of pulmonary veins using a thermoreactive implantable device with external energy transfer: Evaluation in a porcine model

BACKGROUND

Pulmonary vein isolation (PVI) is a well-established method for the treatment of symptomatic paroxysmal atrial fibrillation, but is only partly successful with a high rate of electrical reconnection. We introduce a novel technique in which PVI is accomplished by noninvasive heating of a dedicated thermoresponse implant inserted into the pulmonary veins (PV), demonstrated in a porcine model.

METHODS

A self-expanding nitinol-based implant was positioned in the common inferior PV of 11 pigs, using a fluoroscopy-guided transatrial appendage approach. Ablation was performed through contactless energy transfer from a primary extracorporal coil to a secondary heat ring (HR) embedded in the proximal part of the implant. Electrophysiological conduction was assessed prior to and postablation, and at 3 months. Histological samples were obtained acutely (n  =  4) and after 3 months (n  =  7).

RESULTS

In total, 13 PV implants were successfully positioned in the inferior PVs of 11 animals. Ablation was performed without injury of adjacent structures. PVI and bidirectional block was electrophysiologically confirmed in all cases immediately at the time of implantation and 3 months later in seven chronic animals in whom testing was repeated. Marked evidence of ablation around the proximal HR was evident at 3 months postprocedure, with scar tissue formation and only mild neointimal proliferation.

CONCLUSIONS

Successful PVI can be obtained by external electromagnetic heat transfer to a novel pulmonary vein implant.

Stroke prevention in atrial fibrillation: Past, present and future

Concepts and our approaches to stroke prevention in atrial fibrillation (AF) have changed markedly over the last decade. There has been an evolution over the approach to stroke and bleeding risk assessment, as well as new treatment options. An increasing awareness of AF has led to calls to improve the detection of and population screening for AF. Stroke and bleeding risk assessment continues to evolve, and the ongoing debate on balance between simplicity and practicality, against precision medicine will continue. In this review article, we provide an overview of past, present and the (likely) future concepts and approaches to stroke prevention in AF. We propose three simple steps (the Birmingham ‘3-step’) that offers a practical management pathway to help streamline and simplify decision-making for stroke prevention in patients with AF.

Note: The review process for this paper was fully handled by Christian Weber, Editor in Chief.

Thromboembolisms in atrial fibrillation and heart failure patients with a preserved ejection fraction (HFpEF) compared to those with a reduced ejection fraction (HFrEF)

Heart failure (HF) is classified into three clinical subtypes: HF with a preserved ejection fraction (HFpEF: EF ≥ 50%), HF with a mid-range ejection fraction (HFmrEF: 40 ≤ EF < 49%), and HF with a reduced ejection fraction (HFrEF: EF < 40%). These types often coexist with atrial fibrillation (AF). We investigated the rate of strokes/systemic embolisms (SSEs) in AF patients with HFpEF (AF-HFpEF) compared to that in those with HFrEF (AF-HFrEF: HFmrEF and HFrEF), and examined the independent predictors. We prospectively enrolled 1350 patients admitted to our hospital for worsening HF. We identified 301 patients with either AF-HFpEF (n = 129, 43%) or AF-HFrEF (n = 172, 57%). Compared to the patients with AF-HFrEF, those with AF-HFpEF were older and more likely to be female. Oral anticoagulant use was 63 vs. 66%, respectively. During a mean follow-up period of 26 months, 21 (7%) and 66 (22%) patients had SSEs and all-cause death, respectively. The crude annual rates of SSEs (3.9 vs. 2.7%, P = 0.47) were similar between the groups. In a multivariate Cox regression analysis, an age ≥ 75 years (hazard ratio 2.14, 95% confidence interval 1.32-3.58, P < 0.01) and the plasma B-type natriuretic peptide (BNP) level ≥ 341 pg/ml (hazard ratio 1.60, 95% confidence interval 1.07-2.39, P < 0.05) were associated with SSEs. The EF was not an independent predictor of SSEs (hazard ratio 1.01, 95% confidence interval 0.98-1.04, P = 0.51). There were no significant differences in the rates of SSEs between AF-HFpEF and AF-HFrEF. Patients with HF and concomitant AF should be treated with anticoagulants irrespective of EF.

Atrial fibrillation and heart failure: Factors influencing the choice of oral anticoagulant

Atrial fibrillation (AF) and heart failure (HF) frequently coexist. AF is identified in approximately one third of patients with HF and is linked to increased morbidity and mortality than from either condition alone. AF is relatively more common in HF with preserved ejection fraction (HFpEF) than with reduced ejection fraction (HFrEF). Nevertheless, the risk of stroke and systemic embolism (SSE) is significantly increased with both HF types and the absolute risk is heavily influenced by the presence and severity of associated additional stroke risk factors. The European Society of Cardiology has very recently introduced a third HF subtype entitled HF with mid-range ejection fraction (HFmrEF). At present oral anticoagulation is recommended for all patients with AF and HF, independent of HF type. In addition to warfarin there are currently four non-vitamin K oral anticoagulants (NOACs, previously called novel oral anticoagulants) that have been approved for the prevention of SSE. They consist of one direct thrombin inhibitor, dabigatran and three factor Xa inhibitors: rivaroxaban, apixaban and, most recently, edoxaban. In this review article we present an overview of the evidence to support the use of NOACs for the prevention of SSE in patients with AF and HF and review the influence of HF subtype and co-morbidities on the potential choice of oral anticoagulant.

The C of CHADS: Historical perspective and clinical applications for anticoagulation in patients with non valvular atrial fibrillation and congestive heart failure

The risk stratification of patients with coexisting non valvular atrial fibrillation and congestive heart failure, is often a clinical challenge, as the definitions of congestive heart failure in the popular CHADS2 and CHA2DS2VASc scoring systems, and amongst major clinical trials on Warfarin and Novel Oral Anticoagulants (NOAC) have heterogeneity. Available evidence reveals that any heart failure and/or left ventricular systolic dysfunction is associated with higher rates of stroke/systemic embolism and bleeding in patients with non valvular atrial fibrillation compared to patients without heart failure and normal left ventricular function. Most standard dose NOAC regimens have a better safety and efficacy profile over warfarin in most heart failure sub-group types with a few exceptions including patients with NYHA III/IV on Dabigatran 150mg BID from the RE-LY trial, who had higher major bleeding events, and patients with asymptomatic left ventricular dysfunction (ejection fraction ≤40%) and heart failure with reduced ejection fraction on 20mg of Rivaroxaban in the ROCKET-AF trial, when compared to patients on Warfarin in the corresponding groups. With the gaining popularity and use of NOACs, understanding their safety profile in such situations is paramount.

Stroke prevention in atrial fibrillation

Atrial fibrillation is found in a third of all ischaemic strokes, even more after post-stroke atrial fibrillation monitoring. Data from stroke registries show that both unknown and untreated or under treated atrial fibrillation is responsible for most of these strokes, which are often fatal or debilitating. Most could be prevented if efforts were directed towards detection of atrial fibrillation before stroke occurs, through screening or case finding, and treatment of all patients with atrial fibrillation at increased risk of stroke with well-controlled vitamin K antagonists or non-vitamin K antagonist anticoagulants. The default strategy should be to offer anticoagulant thromboprophylaxis to all patients with atrial fibrillation unless defined as truly low risk by simple validated risk scores, such as CHA2DS2-VASc. Assessment of bleeding risk using the HAS-BLED score should focus attention on reversible bleeding risk factors. Finally, patients need support from physicians and various other sources to start anticoagulant treatment and to ensure adherence to and persistence with treatment in the long term.

Emerging Tools for Stroke Prevention in Atrial Fibrillation

Ischaemic strokes resulting from atrial fibrillation (AF) constitute a devastating condition for patients and their carers with huge burden on health care systems. Prophylactic treatment against systemic embolization and ischaemic strokes is the cornerstone for the management of AF. Effective stroke prevention requires the use of the vitamin K antagonists or non-vitamin K oral anticoagulants (NOACs). This article summarises the latest developments in the field of stroke prevention in AF and aims to assist physicians with the choice of oral anticoagulant for patients with non-valvular AF with different risk factor profile.

The 2014 Atrial Fibrillation Guidelines Companion: A Practical Approach to the Use of the Canadian Cardiovascular Society Guidelines

The Canadian Cardiovascular Society (CCS) Atrial Fibrillation Guidelines Program has generated a comprehensive series of documents regarding the management of atrial fibrillation (AF) between 2010 and 2014. The guidelines provide evidence-based consensus management recommendations in a broad range of areas. These guidelines have proven useful in informing clinical practice, but often lack detail in specifications related to practical application, particularly for areas in which the evidence base is limited or conflicting. Based on feedback from the community, the CCS Atrial Fibrillation Guidelines Committee has identified a number of areas that require clarification to address commonly asked practical questions related to guidelines application. In the present article a number of such questions are presented and suggestions about how they can be answered are suggested. Among the issues considered are: (1) What duration of AF is clinically significant? (2) How are the risk factors in the CCS Algorithm for selecting anticoagulation therapy derived and defined? (3) How is valvular heart disease defined and how do different forms of valve disease affect the choice of anticoagulant therapy for AF patients? (4) How should we quantify renal dysfunction and how does it affect therapeutic choices? The response to these questions and the underlying logic are provided, along with an indication of future research needed where no specific approach can presently be recommended based on the literature.

Attitudes toward anticoagulant treatment among nonvalvular atrial fibrillation patients at high risk of stroke and low risk of bleed

BACKGROUND

Atrial fibrillation (AF) is associated with an increased risk of stroke. Anticoagulant (AC) therapies are effective at treating AF, but carry with them an increased risk of bleed. Research suggests that a large proportion of AF patients who have high risk of stroke and low risk of bleeding are not currently receiving AC treatment. The goal of this study was to understand the reasons why these patients do not engage in this potentially life-saving treatment.

METHOD

Through a self-report online survey, using validated instruments, 1,184 US adults who self-reported a diagnosis of AF were screened for the risk of stroke and bleed. Of these patients, 230 (19.4%) were at high risk of stroke, low risk of bleed, and not currently using an AC treatment, and were asked follow-up questions to assess their reasons for nontreatment, attitudes toward treatment, and attitudes toward dosing regimens.

RESULTS

The most common reasons patients stopped AC treatment were concerns regarding bleeding (27.8%) and other medical concerns (26.6%), whereas the most common reason cited for not being prescribed an AC in the first place was the use of antiplatelet therapy as an alternative (57.1%). In both cases, potentially erroneous decisions regarding perceived stoke and/or bleeding risk were also a factor. Finally, the largest factors regarding attitudes toward treatment and dosing regimen were instructions from an authority figure (eg, physician, pharmacist) and ease of use, respectively.

CONCLUSION

Results suggest that many AF patients who are at high risk of stroke but at low risk of bleed may not be receiving AC due to potentially inaccurate beliefs about risk. This study also found that AF patients place trust in physicians above other factors such as cost when making treatment decisions. Increased education of patients by physicians on the risks and benefits may be a simple strategy to improve outcomes.

Impact of Variations in Kidney Function on Nonvitamin K Oral Anticoagulant Dosing in Patients With Atrial Fibrillation and Recent Acute Heart Failure

INTRODUCTION AND OBJECTIVES

Renal impairment and fluctuations in renal function are common in patients recently hospitalized for acute heart failure and in those with atrial fibrillation. The aim of the present study was to evaluate the hypothetical need for dosage adjustment (based on fluctuations in kidney function) of dabigatran, rivaroxaban and apixaban during the first 6 months after hospital discharge in patients with concomitant atrial fibrillation and heart failure.

METHODS

An observational study was conducted in 162 patients with nonvalvular atrial fibrillation after hospitalization for acute decompensated heart failure who underwent creatinine determinations during follow-up. The hypothetical recommended dosage of dabigatran, rivaroxaban and apixaban according to renal function was determined at discharge. Variations in serum creatinine and creatinine clearance and consequent changes in the recommended dosage of these drugs were identified during 6 months of follow-up.

RESULTS

Among the overall study population, 44% of patients would have needed dabigatran dosage adjustment during follow-up, 35% would have needed rivaroxaban adjustment, and 29% would have needed apixaban dosage adjustment. A higher proportion of patients with creatinine clearance < 60 mL/min or with advanced age (≥ 75 years) would have needed dosage adjustment during follow-up.

CONCLUSIONS

The need for dosage adjustment of nonvitamin K oral anticoagulants during follow-up is frequent in patients with atrial fibrillation after acute decompensated heart failure, especially among older patients and those with renal impairment. Further studies are needed to clarify the clinical importance of these needs for drug dosing adjustment and the ideal renal function monitoring regime in heart failure and other subgroups of patients with atrial fibrillation.