Atrial fibrillation in heart failure: a comprehensive review

Multidisciplinary Approach in Atrial Fibrillation: As Good as Gold

Atrial fibrillation (AF) represents the most common sustained arrhythmia necessitating dual focus: acute complication management and sustained longitudinal oversight to modulate disease progression and ensure comprehensive patient care over time. AF is a multifaceted disorder; due to such a great number of potential exacerbating conditions, a multidisciplinary team (MDT) should manage AF patients by cooperating with a cardiologist. Effective management of AF patients necessitates the implementation of a well-coordinated and tailored care pathway aimed at delivering optimized treatment through collaboration among various healthcare professionals. Management of AF should be carefully evaluated and mutually agreed upon in consultation with healthcare providers. It is crucial to recognize that treatment may evolve due to the emergence of new risk factors, symptoms, disease progression, and advancements in treatment modalities. In the context of multidisciplinary AF teams, a coordinated approach involves assembling a diverse team tailored to meet individual patients' unique needs based on local services' availability.

Cardiac resynchronization therapy (CRT) nonresponders in the contemporary era: A state-of-the-art review

In the 2000s, cardiac resynchronization therapy (CRT) became a revolutionary treatment for heart failure with reduced left ventricular ejection fraction (HFrEF) and wide QRS. However, about one-third of CRT recipients do not show a favorable response. This review of the current literature aims to better define the concept of CRT response/nonresponse. The diagnosis of CRT nonresponder should be viewed as a continuum, and it cannot rely solely on a single parameter. Moreover, baseline features of some patients might predict an unfavorable response. A strong collaboration between heart failure specialists and electrophysiologists is key to overcoming this challenge with multiple strategies. In the contemporary era, new pacing modalities, such as His-bundle pacing and left bundle branch area pacing, represent a promising alternative to CRT. Observational studies have demonstrated their potential; however, several limitations should be addressed. Large randomized controlled trials are needed to prove their efficacy in HFrEF with electromechanical dyssynchrony.

Association of Paroxysmal Versus Persistent Atrial Fibrillation with In-hospital Outcomes and 30-day Readmission After Inpatient Atrial Fibrillation Ablation

Knowledge of the impact of paroxysmal and persistent atrial fibrillation (AF) after catheter ablation on in-hospital outcomes and 30-day readmission remains limited. This study aimed to evaluate the procedural outcomes and 30-day readmission rates among patients with paroxysmal or persistent AF who were hospitalized for AF ablation. Using the Nationwide Readmissions Database, our study included patients aged ≥18 years with AF who were hospitalized and underwent catheter ablation during 2017-2020. Then, we compared the in-hospital procedural outcomes and 30-day readmission rates between patients with paroxysmal and persistent AF, respectively. Our study included 7310 index admissions for paroxysmal AF ablation and 9179 index admissions for persistent AF ablation. According to our analysis, there was no significant difference in procedural complications-namely, cerebrovascular accident, vascular complications, major bleeding requiring blood transfusion, phrenic nerve palsy, pericardial complications, and systemic embolization-between the persistent and paroxysmal AF groups. There was also no significant difference in early mortality between these groups (0.5% vs. 0.7%; P = .22). Persistent AF patients had significantly higher rates of prolonged index hospitalization (9.9% vs. 7.2%; P < .01) and non-home discharge (4.8% vs. 3.1%; P < .01). The 30-day readmission rates were comparable in both groups (10.0% vs. 9.5%; P = .34), with recurrent AF and heart failure being two of the most common causes of cardiac-related readmissions. Catheter ablation among hospitalized patients with paroxysmal or persistent AF resulted in no significant difference in procedural complications, early mortality, or 30-day readmission. This suggests that catheter ablation of AF can be performed with a relatively similar safety profile for both paroxysmal and persistent AF.

Ischemic Stroke and Reduced Left Ventricular Ejection Fraction: A Multidisciplinary Approach to Optimize Brain and Cardiac Health

Reduced left ventricular ejection fraction ≤40%, a known risk factor for adverse cardiac outcomes and recurrent acute ischemic stroke, may be detected during an acute ischemic stroke hospitalization. A multidisciplinary care paradigm informed by neurology and cardiology expertise may facilitate the timely implementation of an array of proven heart failure-specific therapies and procedures in a nuanced manner to optimize brain and cardiac health.

Accelerometer-derived physical activity and the risk of death, heart failure, and stroke in patients with atrial fibrillation: a prospective study from UK Biobank

OBJECTIVE

Data on cardiovascular outcomes according to objectively measured physical activity (PA) in patients with atrial fibrillation (AF) are scarce. This study explored the associations between PA derived from wrist-worn accelerometers and the risk of death, incident heart failure (HF), and incident stroke in patients with AF.

METHODS

From 37 990 patients with AF in UK Biobank, 2324 patients with accelerometer data were included. Weekly moderate-to-vigorous PA (MVPA) duration was computed from accelerometer data. The primary outcome was all-cause mortality. Secondary outcomes were cardiovascular mortality, incident HF, and incident stroke. Restricted cubic splines estimated the dose-response associations between MVPA duration and the outcomes. The adjusted HRs (aHRs) of the outcomes according to adherence to PA standard guidelines (performing MVPA≥150 min/week) were also evaluated.

RESULTS

The mean age was 66.9±6.2 years and 64.9% were male. During a median follow-up of 6.7 years, there were 181 all-cause deaths, 62 cardiovascular deaths, 225 cases of incident HF, and 91 cases of incident stroke; the overall incidence rate per 1000 patient-years was 11.76, 4.03, 15.16 and 5.99, respectively. There was a linear inverse dose-response relationship between MVPA (≥108 min/week) and all-cause mortality. Performing MVPA for 105-590 min/week was associated with a lower risk of HF than those with no measurable MVPA. The risk of stroke and cardiovascular mortality was not associated with MVPA. Performing guideline-adherent MVPA was related to a 30% lower risk of all-cause mortality (aHR: 0.70 (0.50-0.98), p=0.04) and 33% lower risk of HF (aHR 0.67 (0.49-0.93), p=0.02).

CONCLUSION

In patients with AF, accelerometer-derived PA data supports lower risks of all-cause mortality and HF according to a greater level of MVPA and adherence to PA guidelines. Regular MVPA should be encouraged in patients with AF as a part of integrated management.

SGLT2 Inhibitor Use and Risk of Clinical Events in Patients With Cancer Therapy-Related Cardiac Dysfunction

BACKGROUND

Certain antineoplastic therapies are associated with an increased risk of cardiomyopathy and heart failure (HF). Sodium glucose co-transporter 2 (SGLT2) inhibitors improve outcomes in patients with HF.

OBJECTIVES

This study aims to examine the efficacy of SGLT2 inhibitors in patients with cancer therapy-related cardiac dysfunction (CTRCD) or HF.

METHODS

The authors conducted a retrospective cohort analysis of deidentified, aggregate patient data from the TriNetX research network. Patients aged ≥18 years with a history of type 2 diabetes mellitus, cancer, and exposure to potentially cardiotoxic antineoplastic therapies, with a subsequent diagnosis of cardiomyopathy or HF between January 1, 2013, and April 30, 2020, were identified. Patients with ischemic heart disease were excluded. Patients receiving guideline-directed medical therapy were divided into 2 groups based on SGLT2 inhibitor use. After propensity score matching, odds ratios (ORs) and Cox proportional HRs were used to compare outcomes over a 2-year follow-up period.

RESULTS

The study cohort included 1,280 patients with CTRCD/HF (n = 640 per group; mean age: 67.6 years; 41.6% female; 68% White). Patients on SGLT2 inhibitors in addition to conventional guideline-directed medical therapy had a lower risk of acute HF exacerbation (OR: 0.483 [95% CI: 0.36-0.65]; P < 0.001) and all-cause mortality (OR: 0.296 [95% CI: 0.22-0.40]; P = 0.001). All-cause hospitalizations or emergency department visits (OR: 0.479; 95% CI: 0.383-0.599; P < 0.001), atrial fibrillation/flutter (OR: 0.397 [95% CI: 0.213-0.737]; P = 0.003), acute kidney injury (OR: 0.486 [95% CI: 0.382-0.619]; P < 0.001), and need for renal replacement therapy (OR: 0.398 [95% CI: 0.189-0.839]; P = 0.012) were also less frequent in patients on SGLT2 inhibitors.

CONCLUSIONS

SGLT2 inhibitor use is associated with improved outcomes in patients with CTRCD/HF.

Effects of Rhythm Control for Atrial Fibrillation on Cardiac Remodeling and Valvular Regurgitation in Patients with Heart Failure

PURPOSE

Previous studies investigating cardiac remodeling and functional regurgitation of rhythm control for atrial fibrillation (AF) in heart failure (HF) are limited. Therefore, this study aimed to evaluate the impact of rhythm control for AF on cardiac remodeling and functional regurgitation in the spectrum of HF. Its effect on prognosis was explored.

METHODS

According to the treatment strategies of AF, the cohort was classified into the rhythm control and rate control groups. To further detect the implications of rhythm control on cardiac remodeling, functional regurgitation, and outcomes in HF subtypes, patients were further divided into HF with reduced ejection fraction (HFrEF), HF with mildly reduced ejection fraction, and HF with preserved ejection fraction (HFpEF) subgroups.

RESULTS

A total of 828 patients were enrolled, with 307 patients in the rhythm control group and 521 patients in the rate control group. Over a median follow-up time of 3.8 years, patients with rhythm control treatments experienced improvements in biatrial structure parameters, left ventricular ejection fraction, and functional regurgitation (mitral and tricuspid regurgitation) compared with rate control treatment (p < 0.05). Cox regression analysis demonstrated that rhythm control reduced the risks of all-cause mortality (HR 0.436 [95% CI, 0.218-0.871], p = 0.019) in HFpEF and HF-related admissions in HFrEF (HR 0.500 [95% CI, 0.330-0.757], p = 0.001) and HFpEF (HR 0.541 [95% CI, 0.407-0.720], p < 0.001); these associations were similar after adjusting for multiple confounders.

CONCLUSIONS

Rhythm control therapy can be considered an appropriate treatment strategy for the management of AF in HF to improve cardiac remodeling, functional regurgitation, and prognosis.

Catheter Ablation for the Management of Atrial Fibrillation: An Update of the Literature

Catheter ablation has been shown to be more effective at maintaining sinus rhythm and improving quality of life when compared to antiarrhythmic drugs. Radiofrequency and cryoablation are two effective methods. However, catheter-only ablation strategies have not consistently produced high success rates in treating longstanding and persistent AF patients. The emerging treatment of choice for such cases is hybrid ablation, which involves a multidisciplinary and minimally invasive approach to achieve surgical ablation of the direct posterior left atrial wall in combination with endocardial catheter ablation. Studies have shown promising results for the hybrid approach when compared with catheter ablation alone, but it is not without risks. Large and randomised studies are necessary to further evaluate these strategies for managing AF.

Relationships of Whole-Heart Myocardial Mechanics and Cardiac Morphometrics by Transthoracic Echocardiography with Main Prognostic Factors of Heart Failure in Non-Ischemic Dilated Cardiomyopathy

BACKGROUND

there are many prognostic factors of heart failure (HF) based on their evaluation from imaging, to laboratory tests. In clinical practice, it is crucial to use widely available, cheap, and easy-to-use prognostic factors, such as left ventricular ejection fraction (LVEF), New York Heart Association (NYHA) functional class, 6 min walk test (6MWT), B-type natriuretic peptide (BNP), etc. We sought to evaluate the relationships between whole-heart myocardial mechanics and cardiac morphometrics with the main commonly used prognostic factors of HF in patients with non-ischemic dilated cardiomyopathy (NIDCM).

METHODS AND RESULTS

two-dimensional (2D) echocardiography for myocardial mechanics (global longitudinal, radial, and circumferential strains of the left ventricle; right ventricular longitudinal strain; strain values of reservoir, conduit, and contraction function of both atria) and cardiac morphometric (diameters and volumes of both atria and ventricles) parameters were performed, and the HF main traditional prognostic factors were identified. We assessed 109 patients (68.8% male; 49.7 ± 10.5 years) with newly diagnosed NIDCM. Myocardial mechanics and morphometrics were weakly correlated with the patient's age, gender, and smoking (R = 0.2, p < 0.05). Stronger relationships were observed with NYHA class, 6MWT, and BNP (the strongest correlations were with LVEF: R = -0.499, R 0.462, R = -0.461, p < 0.001, respectively). There were moderately strong correlations with LVEF and other whole-heart myocardial mechanics or morphometrics. Moreover, LVEF with global regurgitation volume (GRV) and right ventricle free wall longitudinal strain (RVFWLS) were the most usually detected parameters in multivariate analysis to be associated with changes in HF prognostic factors.

CONCLUSIONS

in NIDCM patients, the main prognostic factors of HF are correlated with whole-heart myocardial mechanics and morphometrics. However, LVEF, GRV, and RVFWLS are the most usually found 2D echocardiographic factors associated with changes in HF prognostic factors.

Risks of Heart Failure, Stroke, and Bleeding in Atrial Fibrillation According to Heart Failure Phenotypes

BACKGROUND

The risks of heart failure (HF) events compared with stroke/systemic embolic events (SEE) or major bleeding (MB) in heart failure with reduced ejection fraction (HFrEF) vs heart failure with preserved ejection fraction (HFpEF) in a large atrial fibrillation (AF) population have not been well-studied.

OBJECTIVES

This study sought to assess HF outcomes, according to HF history and HF phenotypes (HFrEF vs HFpEF), and compare these events with SEE and MB, among patients with AF.

METHODS

We analyzed patients enrolled in the ENGAGE-AF TIMI 48 (Effective Anticoagulation with Factor Xa Next Generation in AF-Thrombolysis in Myocardial Infarction 48) trial. Cumulative incidence of heart failure hospitalization (HHF) or HF death was assessed and compared with the rates of fatal and nonfatal stroke/SEE and MB over a median follow-up of 2.8 years.

RESULTS

Overall, 12,124 (57.4%) had a history of HF (37.7% HFrEF, 40.1% HFpEF, 22.1% with unknown ejection fraction). The rate per 100 person-years (py) of HHF or HF death (4.95; 95% CI: 4.70-5.20) was higher than of fatal and nonfatal stroke/SEE (1.77; 95% CI: 1.63-1.92) and MB (2.66; 95% CI: 2.47-2.86) among patients with HF history. HFrEF patients experienced a higher rate of HHF or HF death compared with HFpEF patients (7.15 vs 3.65; P < 0.001), while the rates of fatal and nonfatal stroke/SEE and MB were similar by HF phenotype. Patients with HF history had a higher rate of mortality after a HHF (1.29; 95% CI: 1.17-1.42) than after a stroke/SEE (0.69; 95% CI: 0.60-0.78) or after MB (0.61; 95% CI: 0.53-0.70). Overall, patients with nonparoxysmal AF had a higher rate of HF and stroke/SEE events regardless of HF history.

CONCLUSIONS

Patients with AF and HF, regardless of ejection fraction, are at a higher risk of HF events with higher subsequent mortality rates than of stroke/SEE or MB. While HFrEF is associated with a higher risk of HF events than HFpEF, the risk of stroke/SEE and MB is similar between HFrEF and HFpEF.

Development and validation of a nomogram for predicting atrial fibrillation in patients with acute heart failure admitted to the ICU: a retrospective cohort study

INTRODUCTION

Acute heart failure is a serious condition. Atrial fibrillation is the most frequent arrhythmia in patients with acute heart failure. The occurrence of atrial fibrillation in heart failure patients worsens their prognosis and leads to a substantial increase in treatment costs. There is no tool that can effectively predict the onset of atrial fibrillation in patients with acute heart failure in the ICU currently.

MATERIALS AND METHODS

We retrospectively analyzed the MIMIC-IV database of patients admitted to the intensive care unit (ICU) for acute heart failure and who were initially sinus rhythm. Data on demographics, comorbidities, laboratory findings, vital signs, and treatment were extracted. The cohort was divided into a training set and a validation set. Variables selected by LASSO regression and multivariate logistic regression in the training set were used to develop a model for predicting the occurrence of atrial fibrillation in acute heart failure in the ICU. A nomogram was drawn and an online calculator was developed. The discrimination and calibration of the model was evaluated. The performance of the model was tested using the validation set.

RESULTS

This study included 2342 patients with acute heart failure, 646 of whom developed atrial fibrillation during their ICU stay. Using LASSO and multiple logistic regression, we selected six significant variables: age, prothrombin time, heart rate, use of vasoactive drugs within 24 h, Sequential Organ Failure Assessment (SOFA) score, and Acute Physiology Score (APS) III. The C-index of the model was 0.700 (95% CI 0.672-0.727) and 0.682 (95% CI 0.639-0.725) in the training and validation sets, respectively. The calibration curves also performed well in both sets.

CONCLUSION

We developed a simple and effective model for predicting atrial fibrillation in patients with acute heart failure in the ICU.

Metabolic Inflexibility as a Pathogenic Basis for Atrial Fibrillation

Atrial fibrillation (AF), the most common sustained arrhythmia, is closely intertwined with metabolic abnormalities. Recently, a metabolic paradox in AF pathogenesis has been suggested: under different forms of pathogenesis, the metabolic balance shifts either towards (e.g., obesity and diabetes) or away from (e.g., aging, heart failure, and hypertension) fatty acid oxidation, yet they all increase the risk of AF. This has raised the urgent need for a general consensus regarding the metabolic changes that predispose patients to AF. “Metabolic flexibility” aptly describes switches between substrates (fatty acids, glucose, amino acids, and ketones) in response to various energy stresses depending on availability and requirements. AF, characterized by irregular high-frequency excitation and the contraction of the atria, is an energy challenge and triggers a metabolic switch from preferential fatty acid utilization to glucose metabolism to increase the efficiency of ATP produced in relation to oxygen consumed. Therefore, the heart needs metabolic flexibility. In this review, we will briefly discuss (1) the current understanding of cardiac metabolic flexibility with an emphasis on the specificity of atrial metabolic characteristics; (2) metabolic heterogeneity among AF pathogenesis and metabolic inflexibility as a common pathological basis for AF; and (3) the substrate-metabolism mechanism underlying metabolic inflexibility in AF pathogenesis.

A Review on Atrial Fibrillation (Computer Simulation and Clinical Perspectives)

Atrial fibrillation (AF), a heart condition, has been a well-researched topic for the past few decades. This multidisciplinary field of study deals with signal processing, finite element analysis, mathematical modeling, optimization, and clinical procedure. This article is focused on a comprehensive review of journal articles published in the field of AF. Topics from the age-old fundamental concepts to specialized modern techniques involved in today’s AF research are discussed. It was found that a lot of research articles have already been published in modeling and simulation of AF. In comparison to that, the diagnosis and post-operative procedures for AF patients have not yet been totally understood or explored by the researchers. The simulation and modeling of AF have been investigated by many researchers in this field. Cellular model, tissue model, and geometric model among others have been used to simulate AF. Due to a very complex nature, the causes of AF have not been fully perceived to date, but the simulated results are validated with real-life patient data. Many algorithms have been proposed to detect the source of AF in human atria. There are many ablation strategies for AF patients, but the search for more efficient ablation strategies is still going on. AF management for patients with different stages of AF has been discussed in the literature as well but is somehow limited mostly to the patients with persistent AF. The authors hope that this study helps to find existing research gaps in the analysis and the diagnosis of AF.

Highlights and comments on EHRA/HRS/APHRS/LAHRS expert consensus on risk assessment in cardiac arrhythmias: use the right tool for the right outcome

Patients with heart disease, or at high risk of developing a cardiac condition, usually undergo risk assessment by primary care physicians, internal medicine doctors, or cardiologists. There are several methods that can be used for this risk assessment, and their applicability differs with respect to availability, complexity, and usefulness in different geographic populations. This document focuses on some of the many relevant clinical topics recently presented in the "Expert Consensus on Risk Assessment in Cardiac Arrhythmias: Use the Right Tool for the Right Outcome," which include statements based on the best available evidence. In this review, we want to highlight and make some pertinent comments on some of the most relevant points of this Consensus.

Comorbidities Associated with One-Year Mortality in Patients with Atrial Fibrillation and Heart Failure

BACKGROUND

Heart failure (HF) and atrial fibrillation (AF) commonly coexist and patients with both diseases have a worse prognosis than those with HF or AF alone. The objective of our study was to identify the factors associated with one-year mortality in patients with HF and AF, depending on the left ventricular ejection fraction (LVEF).

METHODS

We included 727 patients with HF and AF consecutively admitted in a clinical emergency hospital between January 2018 and December 2019. The inclusion criteria were age of more than 18 years, diagnosis of chronic HF and AF (paroxysmal, persistent, permanent), and signed informed consent. The exclusion criteria were the absence of echocardiographic data, a suboptimal ultrasound view, and other cardiac rhythms than AF. The patients were divided into 3 groups: group 1 (337 patients with AF and HF with reduced ejection fraction (HFrEF)), group 2 (112 patients with AF and HF with mid-range ejection fraction (HFmrEF)), and group 3 (278 patients with AF and HF with preserved ejection fraction (HFpEF)).

RESULTS

The one-year mortality rates were 36.49% in group 1, 27.67% in group 2, and 27.69% in group 3. The factors that increased one-year mortality were chronic kidney disease (OR 2.35, 95% CI 1.45-3.83), coronary artery disease (OR 1.67, 95% CI 1.06-2.62), and diabetes (OR 1.66, 95% CI 1.05-2.67) in patients with HFrEF; and hypertension in patients with HFpEF (OR 2.45, 95% CI 1.36-4.39).

CONCLUSIONS

One-year mortality in patients with HF and AF is influenced by different factors, depending on the LVEF.

Update on management of atrial fibrillation in heart failure: a focus on ablation

Atrial fibrillation is increasingly encountered in patients with heart failure. Both diseases have seen tremendous rises in incidence in recent years. In general, the treatment of atrial fibrillation is focused on relieving patients from atrial fibrillation-related symptoms and risk reduction for thromboembolism and the occurrence or worsening of heart failure. Symptomatic relief may be accomplished by either (non-)pharmacological rate or rhythm control in combination with optimal therapy of underlying cardiovascular morbidities and risk factors. Atrial fibrillation ablation has been performed in patients without overt heart failure successfully for many years. However, in recent years, attempts have been made for patients with heart failure as well. In this review, we discuss the current literature describing the treatment of atrial fibrillation in heart failure. We highlight the early rate versus rhythm control studies, the importance of addressing underlying conditions and treatment of risk factors. A critical evaluation will be performed of the catheter ablation studies that have been performed so far in light of larger (post-hoc) ablation studies. Furthermore, we will hypothesise the role of patient selection as next step in optimising outcome for patient with atrial fibrillation and heart failure.

Association between exercise habits and stroke, heart failure, and mortality in Korean patients with incident atrial fibrillation: A nationwide population-based cohort study

BACKGROUND

There is a paucity of information about cardiovascular outcomes related to exercise habit change after a new diagnosis of atrial fibrillation (AF). We investigated the association between exercise habits after a new AF diagnosis and ischemic stroke, heart failure (HF), and all-cause death.

METHODS AND FINDINGS

This is a nationwide population-based cohort study using data from the Korea National Health Insurance Service. A retrospective analysis was performed for 66,692 patients with newly diagnosed AF between 2010 and 2016 who underwent 2 serial health examinations within 2 years before and after their AF diagnosis. Individuals were divided into 4 categories according to performance of regular exercise, which was investigated by a self-reported questionnaire in each health examination, before and after their AF diagnosis: persistent non-exercisers (30.5%), new exercisers (17.8%), exercise dropouts (17.4%), and exercise maintainers (34.2%). The primary outcomes were incidence of ischemic stroke, HF, and all-cause death. Differences in baseline characteristics among groups were balanced considering demographics, comorbidities, medications, lifestyle behaviors, and income status. The risks of the outcomes were computed by weighted Cox proportional hazards models with inverse probability of treatment weighting (IPTW) during a mean follow-up of 3.4 ± 2.0 years. The new exerciser and exercise maintainer groups were associated with a lower risk of HF compared to the persistent non-exerciser group: the hazard ratios (HRs) (95% CIs) were 0.95 (0.90-0.99) and 0.92 (0.88-0.96), respectively (p < 0.001). Also, performing exercise any time before or after AF diagnosis was associated with a lower risk of mortality compared to persistent non-exercising: the HR (95% CI) was 0.82 (0.73-0.91) for new exercisers, 0.83 (0.74-0.93) for exercise dropouts, and 0.61 (0.55-0.67) for exercise maintainers (p < 0.001). For ischemic stroke, the estimates of HRs were 10%-14% lower in patients of the exercise groups, yet differences were statistically insignificant (p = 0.057). Energy expenditure of 1,000-1,499 MET-min/wk (regular moderate exercise 170-240 min/wk) was consistently associated with a lower risk of each outcome based on a subgroup analysis of the new exerciser group. Study limitations include recall bias introduced due to the nature of the self-reported questionnaire and restricted external generalizability to other ethnic groups.

CONCLUSIONS

Initiating or continuing regular exercise after AF diagnosis was associated with lower risks of HF and mortality. The promotion of exercise might reduce the future risk of adverse outcomes in patients with AF.

Atrial fibrillation in patients with systolic heart failure: pathophysiology mechanisms and management

Heart failure (HF) and atrial fibrillation (AF) demonstrate a constantly increasing prevalence during the 21^st century worldwide, as a result of the aging population and the successful interventions of the clinical practice in the deterioration of adverse cardiovascular outcomes. HF and AF share common risk factors and pathophysiological mechanisms, creating the base of a constant interrelation. AF impairs systolic and diastolic function, resulting in the increasing incidence of HF, whereas the structural and neurohormonal changes in HF with preserved or reduced ejection fraction increase the possibility of the AF development. The temporal relationship of the development of either condition affects the diagnostic algorithms, the prognosis and the ideal therapeutic strategy that leads to euvolaemia, management of non-cardiovascular comorbidities, control of heart rate or restoration of sinus rate, ventricular synchronization, prevention of sudden death, stroke, embolism, or major bleeding and maintenance of a sustainable quality of life. The indicated treatment for the concomitant HF and AF includes rate or/and rhythm control as well as thromboembolism prophylaxis, while the progress in the understanding of their pathophysiological interdependence and the introduction of the genetic profiling, create new paths in the diagnosis, the prognosis and the prevention of these diseases.

Impact of atrial fibrillation on stroke, heart failure, and mortality in diabetic patients with coronary artery disease

PURPOSE

The objective of this study was to evaluate the risk of stroke, heart failure (HF) and mortality in diabetic patients with coronary artery disease (CAD) with a diagnosis of atrial fibrillation (AF).

METHODS

The study population was identified as the diabetic patients presented with CAD from 2000 to 2011 and the case group was those with a diagnosis of AF whereas the control group did not have AF. The cumulative incidence of stroke, heart failure and mortality was demonstrated by Kaplan-Meier curves and the difference between the two groups was estimated by log-rank test. The Cox proportional hazard model was used to calculate the risk of the factors to the event, and the results were expressed by hazard ratios (HRs) and 95% confidence intervals (95% CIs).

RESULTS

After controlling for the covariates, the risk of stroke, heart failure and mortality was 1.63-fold higher (adjusted HR =1.63, 95% CI =1.37-1.94) , 2.75-fold higher (adjusted HR = 2.75, 95% CI =2.25-3.36), 1.72-fold higher (adjusted HR = 1.72, 95% CI = 1.43-2.07) in the AF cohort compared to the non-AF cohort.

CONCLUSION

After adjusting for the confounding factors, increased risk of stroke, heart failure, and mortality by 1.63, 2.75, 1.72 times with a concomitant diagnosis of AF in diabetic CAD patients was observed in this study.

Quantifying changes in size of arrhythmic photoplethysmography waveforms during a Valsalva maneuver for assessing cardiac filling pressure

OBJECTIVE

We previously showed that the change in amplitude of a finger photoplethysmography waveform during the Valsalva maneuver reflects cardiac filling pressure. However, the automated determination of peaks and valleys to calculate amplitude is limited in significant arrhythmias such as atrial fibrillation and premature ventricular complexes, which are common in heart failure. The purpose of this study was to assess the change in size of the waveform by calculating the change in root mean square (RMS) of the signal, thereby utilizing the entire cardiac cycle, and to compare it to change in size of peak-to-valley amplitude.

APPROACH

We compared the two approaches in signals obtained from participants of a prior study who were tested prior to a clinically indicated cardiac catheterization. Correlation between the two methods was assessed in cases without, and then with, significant arrhythmias including atrial fibrillation or premature ventricular complexes.

MAIN RESULTS

Calculations from the two methods of peak-valley amplitude and RMS were highly correlated with each other in signals without (0.99, p < 0.0001, n = 252) and with significant arrhythmias (0.90, p < 0.0001, n = 34).

SIGNIFICANCE

RMS analysis of photoplethysmography signal size during the Valsalva maneuver is highly correlated with the method of analyzing changes in peak-valley amplitude, but does not rely on identifying peaks and valleys. The RMS method may be a more robust automated method of assessing cardiac filling pressure in patients with significant arrhythmias.

Predictors of acute hospital mortality and length of stay in patients with new-onset atrial fibrillation: a first-hand experience from a medical emergency team response provider

BACKGROUND

Atrial fibrillation (AF) occurs frequently following cardiothoracic surgery and treatment decisions are informed by evidence-based clinical guidelines. Outside this setting there are few data to guide clinical management.

AIM

To describe the characteristics, management and outcomes of hospitalised adult patients with new-onset AF.

METHODS

The medical emergency team (MET) database was utilised to identify patients who had a 'MET call' activated for tachycardia between 2015 and 2016. Patients with sinus tachycardia, pre-existing AF/atrial flutter or other known tachyarrhythmia were excluded. Primary outcomes were length of hospital stay and in-hospital mortality.

RESULTS

New-onset AF was identified in 137 patients: 68 medically managed; 38 non-cardiothoracic post-operative; and 31 cardiothoracic post-operative. Mean age was 74 ± 11.6 years and 72 (53%) were male. Of 79 patients who underwent echocardiography, 80% had left atrial dilatation and 14% had reduced left ventricular ejection fraction (LVEF). Mean length of stay (LOS) was 12 days and in-hospital mortality rate was 11%. On multivariable analysis, the odds of death during acute hospitalisation was 7.4 times higher in patients with heart failure with reduced LVEF (odds ratio 7.4, 95% confidence interval (CI) 1.23-44.8, P = 0.028). Length of acute hospital stay increased by 36% if the duration of AF was longer than 48 h (beta coefficient 0.36, 95% CI -0.015 to 0.74, P = 0.059).

CONCLUSION

Left ventricular systolic dysfunction in hospitalised patients with new-onset AF is associated with increased all-cause mortality whereas lower serum potassium levels are associated with an increased LOS. A prospective study is planned to compare outcomes based on in-hospital treatment strategies.

Pharmacological management of atrial fibrillation in patients with heart failure with reduced ejection fraction: review of current knowledge and future directions

Introduction: Both heart failure with reduced ejection fraction (HFrEF) and atrial fibrillation (AF) independently cause significant morbidity and mortality. The two conditions commonly coexist and AF in the setting of HFrEF is associated with worse mortality, hospitalizations, and quality of life compared to HFrEF without AF. Despite the large burden of these conditions, there is no clear optimal management strategy for when they occur together.Areas covered: This review focuses on the pharmacological management of AF in HFrEF. Studies were identified through PubMed search of relevant keywords. The authors review key clinical trials that have influenced management strategies and guidelines. The authors focus on the classes of drugs used to treat AF for both rate and rhythm control strategies including beta-blockers, digoxin, amiodarone, and dofetilide. Additionally, the authors discuss select non-antiarrhythmic medications that affect AF in HFrEF. The authors highlight the strengths and weakness of the data supporting the use of these medications and suggest future directions.Expert opinion: The pharmacological treatment of AF in HFrEF will need further refinement alongside the emerging role of catheter ablation. Novel HF medications and antiarrhythmics offer new tools to prevent the development of AF, as well as for rate and rhythm control strategies.

Incidence, Risk Factors and Subsequent Prognostic Impact of New-Onset Atrial Fibrillation in Infective Endocarditis

BACKGROUND

Few studies with a large sample size have been performed to evaluate the incidence, risk factors and prognostic value of new-onset atrial fibrillation (AF) in patients with infective endocarditis (IE).Methods and Results:A total of 1,063 IE patients were included and 83 developed new AF. Compared with no-AF, the incidence of in-hospital death (6.0% vs. 22.9%, P<0.001) was higher in patients with new-onset AF. New-onset AF was independently associated with increased risk of in-hospital (adjusted odds ratio [OR]=3.92, P=0.001) and 1-year death (adjusted hazard ratio=2.91, P=0.001), while prior AF was not an independent factor. Kaplan-Meier curve analysis demonstrated new-onset AF mainly affected short-term death (180 days). Age (OR=1.04, P<0.001), rheumatic heart disease (OR=1.88, P=0.022), NYHA Class III or IV (OR=2.09, P=0.003), and left atrial diameter (LAD; OR=1.05, P=0.006) were independent risk factors for development of new AF.

CONCLUSIONS

New-onset AF, not prior AF, was a prognostic factor in IE patients, which was mainly associated with increased risk of short-term death. Patients with concomitant rheumatic heart disease, poor cardiac function, and larger LAD had higher risk of developing new AF.

Opportunistic Screening for Atrial Fibrillation in the Pharmacies: A Population-Based Cross-Sectional Study

INTRODUCTION

Opportunistic screening of atrial fibrillation is a valuable approach to the identification of subjects with unknown or non-symptomatic atrial fibrillation (AF) with the potential of reducing the burden of ischemic stroke in the population.

AIM

To evaluate the feasibility of a large-scale screening for atrial fibrillation using a blood pressure monitor (MicrolifeAFIB) endowed with a validated algorithm able to detect AF calculating the irregularity of interval times between heartbeats.

METHODS

In this cross-sectional study conducted in 74 pharmacies in Verona participated 3071 people aged 50 years or more. In 6 months, information about drugs, previous diagnoses of cardiovascular diseases, anthropometric and demographic data was recorded, together with the measurement of blood pressure and cardiac rhythm by using the MicrolifeAFIB device. Pharmacists also collected anthropometric and demographic data of the participants, along with information concerning their personal history of cardiovascular disease and the use of antihypertensive and antithrombotic agents. All those who were positive at the screening for atrial fibrillation were referred to their family doctor.

RESULTS

The screening revealed 98 subjects (3.2%) positive for AF; 44 of these reported a previous diagnosis of AF and were treated with anticoagulants (77%) or with antiplatelet agents (7%). By logistic regression analysis, age, male sex and heart failure were independently associated with positivity for AF. Association between positive test and previous stroke/TIA was found in the 54 subjects without a previous diagnosis of AF (9% had a previous stroke/TIA).

CONCLUSIONS

Opportunistic screening for atrial fibrillation in the pharmacies is feasible and allows to identify a number of subjects with silent, non-previously diagnosed AF, therefore is potentially useful in large-scale projects aimed at the prevention of cardiovascular morbidity and mortality.

Prognostic significance of changes in heart rate following uptitration of beta-blockers in patients with sub-optimally treated heart failure with reduced ejection fraction in sinus rhythm versus atrial fibrillation

BACKGROUND

In patients with heart failure with reduced ejection fraction (HFrEF) on sub-optimal doses of beta-blockers, it is conceivable that changes in heart rate following treatment intensification might be important regardless of underlying heart rhythm. We aimed to compare the prognostic significance of both achieved heart rate and change in heart rate following beta-blocker uptitration in patients with HFrEF either in sinus rhythm (SR) or atrial fibrillation (AF).

METHODS

We performed a post hoc analysis of the BIOSTAT-CHF study. We evaluated 1548 patients with HFrEF (mean age 67 years, 35% AF). Median follow-up was 21 months. Patients were evaluated at baseline and at 9 months. The combined primary outcome was all-cause mortality and heart failure hospitalisation stratified by heart rhythm and heart rate at baseline.

RESULTS

Despite similar changes in heart rate and beta-blocker dose, a decrease in heart rate at 9 months was associated with reduced incidence of the primary outcome in both SR and AF patients [HR per 10 bpm decrease-SR: 0.83 (0.75-0.91), p < 0.001; AF: 0.89 (0.81-0.98), p = 0.018], whereas the relationship was less strong for achieved heart rate in AF [HR per 10 bpm higher-SR: 1.26 (1.10-1.46), p = 0.001; AF: 1.08 (0.94-1.23), p = 0.18]. Achieved heart rate at 9 months was only prognostically significant in AF patients with high baseline heart rates (p for interaction 0.017 vs. low).

CONCLUSIONS

Following beta-blocker uptitration, both achieved and change in heart rate were prognostically significant regardless of starting heart rate in SR, however, they were only significant in AF patients with high baseline heart rate.

Invasive therapies for patients with concomitant heart failure and atrial fibrillation

Atrial fibrillation (AF) and heart failure (HF) are two clinical entities that can present either separately or concurrently. One entity can lead to the other and vice versa as AF can not only be the underlying etiology of HF but also exacerbate HF due to other cardiac diseases. Besides prevention of cerebral and systemic embolism and elimination of AF-related symptoms, restoration of sinus rhythm for AF patients helps to avoid or reduce HF, irrespective of their underlying heart disease. Successful rates of medical therapy for AF are low in persistent AF, and much lower in long-standing AF, while invasive procedures for AF yield promising results. In this review, the authors evaluate the value of invasive therapies for HF patients complicated with non-valvular AF. We examine this clinical problem by interpreting the relationships between these two entities: the mechanism of tachycardia-induced cardiomyopathy (TIC), past opinions about rhythm control and rate control of AF, discrimination of HF-related AF and AF-induced HF, how to identify the AF patients that could benefit from invasive therapies, and how to select invasive therapies for different AF patients and peri-operative treatments.

Revisiting Atrioventricular Nodal Ablation and Cardiac Pacing of Atrial Fibrillation in a Patient with Dextrocardia

Patient: Female, 77

Final Diagnosis: Tachycardia induced cardiomyopathy

Symptoms: Shortness of breath

Medication: —

Clinical Procedure: —

Specialty: Cardiology

Mortality and Atrial Fibrillation in the FIACA Study: Evidence of a Differential Effect According to Admission Diagnosis

INTRODUCTION AND OBJECTIVES

Atrial fibrillation (AF) is an independent risk factor for mortality in several diseases. However, data published in acute decompensated heart failure (DHF) are contradictory. Our objective was to investigate the impact of AF on mortality in patients admitted to hospital for DHF compared with those admitted for other reasons.

METHODS

This retrospective cohort study included all patients admitted to hospital within a 10-year period due to DHF, acute myocardial infarction (AMI), or ischemic stroke (IS), with a median follow-up of 6.2 years.

RESULTS

We included 6613 patients (74 ± 11 years; 54.6% male); 2177 with AMI, 2208 with DHF, and 2228 with IS. Crude postdischarge mortality was higher in patients with AF hospitalized for AMI (incident rate ratio, 2.48; P < .001) and IS (incident rate ratio, 1.84; P < .001) than in those without AF. No differences were found in patients with DHF (incident rate ratio, 0.90; P = .12). In adjusted models, AF was not an independent predictor of in-hospital mortality by clinical diagnosis. However, AF emerged as an independent predictor of postdischarge mortality in patients with AMI (HR, 1.494; P = .001) and IS (HR, 1.426; P < .001), but not in patients admitted for DHF (HR, 0.964; P = .603).

CONCLUSIONS

AF was as an independent risk factor for postdischarge mortality in patients admitted to hospital for AMI and IS but not in those admitted for DHF.

[Epidemiology of the relationship between atrial fibrillation and heart failure]

La fibrillation atriale et l’insuffisance cardiaque sont des maladies cardiovasculaires souvent associées, leur coexistence aggrave le pronostic et constitue un problème de santé public majeur. L’objectif de cette étude est d’évaluer la prévalence de la fibrillation atriale chez les patients en insuffisance cardiaque chronique et déterminer le profil clinique de ce groupe de patients. Nous avons conduit une étude rétrospective descriptive basée sur le registre d'insuffisance cardiaque du département de cardiologie du centre hospitalier universitaire de juin 2006 à Mars 2015.Nous avons inclus les patients âgés de plus de 18 ans ayant une insuffisance cardiaque chronique avec une fibrillation atriale. Durant cette période 3048 patients ayant une insuffisance cardiaque chronique avec fibrillation atriale(FA) ont été inclus. La prévalence de la fibrillation atriale était de 10,6%. La fréquence des facteurs de risque cardiovasculaires associée à (FA) était de: (54%) pour l'hypertension artérielle, (39%) pour le diabète, (8%) pour la dyslipidémie, (26%) pour le tabac, (30%) pour la sédentarité et (17%) pour la ménopause. La (FA) était présente chez (67,4%) des hommes versus (32,6%) des femmes. Les étiologies de l'insuffisance cardiaque chronique associées à la fibrillation atriale étaient: les valvulopathies (44,1%); les coronaropathies (32%); Hypertensives (11%), primitive (10%), toxiques (2%) et alcoolisme chronique (1%). La fibrillation atriale reste fréquente dans la population des patients insuffisants cardiaques au Maroc et la moyenne d’âge est inférieure à celle retrouvée dans la littérature.

Novel Compounds Targeting the Mitochondrial Protein VDAC1 Inhibit Apoptosis and Protect against Mitochondrial Dysfunction

Apoptosis is thought to play a critical role in several pathological processes, such as neurodegenerative diseases (i.e. Parkinson's and Alzheimer's diseases) and various cardiovascular diseases. Despite the fact that apoptotic mechanisms are well defined, there is still no substantial therapeutic strategy to stop or even slow this process. Thus, there is an unmet need for therapeutic agents that are able to block or slow apoptosis in neurodegenerative and cardiovascular diseases. The outer mitochondrial membrane protein voltage-dependent anion channel 1 (VDAC1) is a convergence point for a variety of cell survival and death signals, including apoptosis. Recently, we demonstrated that VDAC1 oligomerization is involved in mitochondrion-mediated apoptosis. Thus, VDAC1 oligomerization represents a prime target for agents designed to modulate apoptosis. Here, high-throughput compound screening and medicinal chemistry were employed to develop compounds that directly interact with VDAC1 and prevent VDAC1 oligomerization, concomitant with an inhibition of apoptosis as induced by various means and in various cell lines. The compounds protected against apoptosis-associated mitochondrial dysfunction, restoring dissipated mitochondrial membrane potential, and thus cell energy and metabolism, decreasing reactive oxidative species production, and preventing detachment of hexokinase bound to mitochondria and disruption of intracellular Ca²⁺ levels. Thus, this study describes novel drug candidates with a defined mechanism of action that involves inhibition of VDAC1 oligomerization, apoptosis, and mitochondrial dysfunction. The compounds VBIT-3 and VBIT-4 offer a therapeutic strategy for treating different diseases associated with enhanced apoptosis and point to VDAC1 as a promising target for therapeutic intervention.

Atrial fibrillation management in older heart failure patients: a complex clinical problem

BACKGROUND

Atrial fibrillation (AF) and heart failure (HF), two problems of growing prevalence as a consequence of the ageing population, are associated with high morbidity, mortality, and healthcare costs. AF and HF also share common risk factors and pathophysiologic processes such as hypertension, diabetes mellitus, ischemic heart disease, and valvular heart disease often occur together. Although elderly patients with both HF and AF are affected by worse symptoms and poorer prognosis, there is a paucity of data on appropriate management of these patients.

METHODS

PubMed was searched for studies on AF and older patients using the terms atrial fibrillation, elderly, heart failure, cognitive impairment, frailty, stroke, and anticoagulants.

RESULTS

The clinical picture of HF patients with AF is complex and heterogeneous with a higher prevalence of frailty, cognitive impairment, and disability. Because of the association of mental and physical impairment to non-administration of oral anticoagulants (OACs), screening for these simple variables in clinical practice may allow better strategies for intervention in this high-risk population. Since novel direct OACs (NOACs) have a more favorable risk-benefit profile, they may be preferable to vitamin K antagonists (VKAs) in many frail elderly patients, especially those at higher risk of falls. Moreover, NOACs are simple to administer and monitor and may be associated with better adherence and safety in patients with cognitive deficits and mobility impairments.

CONCLUSIONS

Large multicenter longitudinal studies are needed to examine the effects of VKAs and NOACs on long-term cognitive function and frailty; future studies should include geriatric conditions.

Association of cardiac cachexia and atrial fibrillation in heart failure patients

BACKGROUND

Cachexia is a common complication in patients with advanced heart failure (HF) associated with inflammatory response activation. Atrial fibrillation (AF) is the most frequent arrhythmia (26%), probably both exacerbate the cardiac cachexia (CC).

OBJECTIVES

Evaluate the association of cardiac cachexia and atrial fibrillation in heart failure patients.

MATERIAL AND METHODS

In a case control study, CC was diagnosed by electrical bioimpedance with vectorial analysis (BIVA). Subjects with congenital heart disease, cancer, HIV, drug use and other causes than HF were excluded.

RESULTS

Of the 359 subjects analyzed (men: 52.9%) median age 65years (55-74). Those with CC were older [72 (61-67)] vs. without [62 (52-70) years old, p<0.01]. During follow-up 47.8% of subjects developed CC and 17.27% AF, this was significantly more frequent in cachectic patients CC (23% vs 12.11%, OR: 2.17, 95% CI: 1.19-4.01, p=0.006). Subjects, with AF had lower left ventricular ejection fraction (25.49±12.96 vs. 32.01±15.02, p=0.08), lower posterior wall thickness (10.03±2.12 vs. 11.00±2.47, p=0.007), larger diameter of the left atrium (49.87±9.84 vs. 42.66±7.56, p<0.001), and a higher prevalence of CC (85.42% vs. 69.77%, p=0.028). The 50.58% of was in NYHA class I. In NYHA III, 22.95% were in AF vs. 12.10% with not AF (p=0.027).

CONCLUSION

The frequent coexistence of CC and AF as HF complications indicate greater severity of HF, regardless of its type of HF.

The current approach of atrial fibrillation management

Atrial fibrillation (AF) is the most commonly encountered arrhythmia in clinical practice. Aging populations coupled with improved outcomes for many chronic medical conditions has led to increases in AF diagnoses. AF is also known to be associated with an increased risk of adverse events such as transient ischemic attack, ischemic stroke, systemic embolism, and death. This association is enhanced in select populations with preexisting comorbid conditions such as chronic heart failure. The aim of this review is to highlight the advances in the field of cardiology in the management of AF in both acute and long-term settings. We will also review the evolution of anticoagulation management over the past few years and landmark trials in the development of novel oral anticoagulants (NOACs), reversal agents for new NOACs, nonpharmacological options to anticoagulation therapy, and the role of implantable loop recorder in AF management.

Atrial fibrillation in heart failure: what should we do?

Heart failure (HF) and atrial fibrillation (AF) are two conditions that are likely to dominate the next 50 years of cardiovascular (CV) care. Both are increasingly prevalent and associated with high morbidity, mortality, and healthcare cost. They are closely inter-related with similar risk factors and shared pathophysiology. Patients with concomitant HF and AF suffer from even worse symptoms and poorer prognosis, yet evidence-based evaluation and management of this group of patients is lacking. In this review, we evaluate the common mechanisms for the development of AF in HF patients and vice versa, focusing on the evidence for potential treatment strategies. Recent data have suggested that these patients may respond differently than those with HF or AF alone. These results highlight the clear clinical need to identify and treat according to best evidence, in order to prevent adverse outcomes and reduce the huge burden that HF and AF are expected to have on global healthcare systems in the future. We propose an easy-to-use clinical mnemonic to aid the initial management of newly discovered concomitant HF and AF, the CAN-TREAT HFrEF + AF algorithm (Cardioversion if compromised; Anticoagulation unless contraindication; Normalize fluid balance; Target initial heart rate <110 b.p.m.; Renin-angiotensin-aldosterone modification; Early consideration of rhythm control; Advanced HF therapies; Treatment of other CV disease).

A review on atrioventricular junction ablation and pacing for heart rate control of atrial fibrillation

Atrioventricular junction ablation with permanent pacemaker implantation is a highly effective treatment approach in patients with atrial fibrillation and high ventricular rates resistant to other treatment modalities, especially in the elderly or those with severe comorbidities. Compared with pharmacological therapy alone, the so-called “ablate and pace” approach offers the potential for more robust control of ventricular rate. Atrioventricular junction ablation and pacing strategy is associated with improvement in symptoms, quality of life, and exercise capacity. Given the close relationship between atrial fibrillation and heart failure, there is a particular benefit of such a rate control in patients with atrial fibrillation and reduced systolic function. There is increasing evidence that cardiac resynchronization therapy devices may be beneficial in selected populations after atrioventricular junction ablation. The present review article focuses on the current recommendations for atrioventricular junction ablation and pacing for heart rate control in patients with atrial fibrillation. The technique, the optimal implantation time, and the proper device selection after atrioventricular junction ablation are also discussed.

Biological significance of miR-126 expression in atrial fibrillation and heart failure

We investigated the biological significance of microRNA-126 (miR-126) expression in patients with atrial fibrillation (AF) and/or heart failure (HF) to examine the possible mechanism of miR-126-dependent AF and development of HF. A total of 103 patients were divided into three groups: AF group (18 men and 17 women, mean age: 65.62±12.72 years), HF group (17 men and 15 women, mean age: 63.95±19.71 years), and HF-AF group (20 men and 16 women, mean age: 66.56±14.37 years). Quantitative real-time PCR was used to measure relative miR-126 expression as calculated by the 2-ΔΔCt method. miR-126 was frequently downregulated in the 3 patient groups compared with controls. This reduction was significantly lower in permanent and persistent AF patients than in those with paroxysmal AF (P<0.05, t-test). Moreover, miR-126 expression was markedly lower in the HF-AF group compared with the AF and HF groups. The 3 patient groups had higher N-terminal prohormone brain natriuretic peptide (NT-proBNP) levels, lower left ventricular ejection fraction (LVEF), larger left atrial diameter, and higher cardiothoracic ratio compared with controls. There were significant differences in NT-proBNP levels and LVEF among the AF, HF, and HF-AF groups. Pearson correlation analysis showed that relative miR-126 expression was positively associated with LVEF, logarithm of NT-proBNP, left atrial diameter, cardiothoracic ratio, and age in HF-AF patients. Multiple linear regression analysis showed that miR-126 expression was positively correlated with LVEF, but negatively correlated with the logarithm of NT-pro BNP and the cardiothoracic ratio (all P<0.05). Serum miR-126 levels could serve as a potential candidate biomarker for evaluating the severity of AF and HF. However, to confirm these results, future studies with a larger and diverse patient population are necessary.