Heart Failure in Atrial Fibrillation - An Update on Clinical and Echocardiographic Implications

Incremental value of diastolic wall strain in predicting heart failure events in patients with atrial fibrillation

Diastolic wall strain (DWS), an echocardiographic index based on linear elasticity theory, has been identified as a predictor of heart failure (HF) in patients with sinus rhythm. However, its effectiveness in atrial fibrillation (AF) patients remains uncertain. This study aims to assess DWS as a predictor of HF in AF patients with preserved ejection fraction. We analysed a prospective database of AF patients undergoing transthoracic echocardiography. AF patients with reduced left ventricular ejection fraction (< 50%), posterior wall motion abnormality, hypertrophic cardiomyopathy, valvular heart disease, pericardial disease, congenital heart disease, or history of pacemaker/implantable cardioverter-defibrillator implantation or cardiac surgery were excluded. The study followed patients until HF development, death, or last visit. Follow-up for patients who underwent catheter ablation was censored on the date of their procedure. HF was ascertained based on the Framingham criteria. DWS was calculated using a validated formula: DWS = (PWs -PWd)/PWs, where PWs is the posterior wall thickness at end-systole and PWd is the posterior wall thickness at end-diastole. Among 411 study patients (mean age 69.6 years, 66% men), 20 (5%) was underwent catheter ablation and 57 (14%) developed HF during a mean follow-up of 82 months. Cox-proportional hazards demonstrated that low DWS (≤ 0.33) significantly predicted HF events (hazard ratio [HR] 3.28, 95% confidence interval [CI]) 1.81-5.94, P < 0.0001), independent of age (per 10 years; HR 1.99, 95% CI 1.35-2.93, P < 0.001), indexed left ventricular mass (per 10 g/m2; HR 1.16, 95% CI 1.05-1.27, P < 0.01), and indexed left atrial volume (per 10 mL/m2; HR 1.14, 95% CI 1.04-1.24, P < 0.01). Additionally, global log-likelihood ratio chi-square statistics indicated that DWS incrementally predicts HF development beyond age, indexed left ventricular mass, and left atrial volume (P < 0.001).

Development of automated neural network prediction for echocardiographic left ventricular ejection fraction

Introduction

The echocardiographic measurement of left ventricular ejection fraction (LVEF) is fundamental to the diagnosis and classification of patients with heart failure (HF).

Methods

This paper aimed to quantify LVEF automatically and accurately with the proposed pipeline method based on deep neural networks and ensemble learning. Within the pipeline, an Atrous Convolutional Neural Network (ACNN) was first trained to segment the left ventricle (LV), before employing the area-length formulation based on the ellipsoid single-plane model to calculate LVEF values. This formulation required inputs of LV area, derived from segmentation using an improved Jeffrey's method, as well as LV length, derived from a novel ensemble learning model. To further improve the pipeline's accuracy, an automated peak detection algorithm was used to identify end-diastolic and end-systolic frames, avoiding issues with human error. Subsequently, single-beat LVEF values were averaged across all cardiac cycles to obtain the final LVEF.

Results

This method was developed and internally validated in an open-source dataset containing 10,030 echocardiograms. The Pearson's correlation coefficient was 0.83 for LVEF prediction compared to expert human analysis (p < 0.001), with a subsequent area under the receiver operator curve (AUROC) of 0.98 (95% confidence interval 0.97 to 0.99) for categorisation of HF with reduced ejection (HFrEF; LVEF<40%). In an external dataset with 200 echocardiograms, this method achieved an AUC of 0.90 (95% confidence interval 0.88 to 0.91) for HFrEF assessment.

Conclusion

The automated neural network-based calculation of LVEF is comparable to expert clinicians performing time-consuming, frame-by-frame manual evaluations of cardiac systolic function.

Trends in prevalence of major etiologies leading to heart failure in young patients: An integrative review

The prevalence of Heart failure (HF) is increasing with the aging of the population but it is estimated that 10% of HF patients are younger than 50 years-old. HF development in this population is characterized with a fast-growing prevalence, and important disparities according to underlying etiologies or gender. These observations highlight the need to identify specific and preventable factors in these patients, a topic that is under-studied. Here we provide an overview of trends in prevalence of major etiologies leading to HF in young subjects, including genetic factors associated with cardiomyopathies, premature vascular dysfunction and related ischemia, metabolic stress, cardio-toxic responses to different agents, and myocarditis. We also highlight the increasing influence of major risk factors that are driving HF in younger patients, such as obesity, diabetes or arterial hypertension.

Heart failure in older patients with atrial fibrillation: incidence and risk factors

INTRODUCTION AND OBJECTIVES

Atrial fibrillation (AF) is linked to heart failure (HF). However, little has been published on the factors that may precipitate the onset of HF in AF patients. We aimed to determine the incidence, predictors, and prognosis of incident HF in older patients with AF with no prior history of HF.

METHODS

Patients with AF older than 80 years and without prior HF were identified between 2014 and 2018.

RESULTS

A total of 5794 patients (mean age, 85.2±3.8 years; 63.2% women) were followed up for 3.7 years. Incident HF, predominantly with preserved left ventricular ejection fraction, developed in 33.3% (incidence rate, 11.5-100 people-year). Multivariate analysis identified 11 clinical risk factors for incident HF, irrespective of HF subtype: significant valvular heart disease (HR, 1.99; 95%CI, 1.73-2.28), reduced baseline left ventricular ejection fraction (HR, 1.92; 95%CI, 1.68-2.19), chronic pulmonary obstructive disease (HR, 1.59; 95%CI, 1.40-1.82), enlarged left atrium (HR 1.47, 95%CI 1.33-1.62), renal dysfunction (HR 1.36, 95%CI 1.24-1.49), malnutrition (HR, 1.33; 95%CI, 1.21-1.46), anemia (HR, 1.30; 95%CI, 1.17-1.44), permanent AF (HR, 1.15; 95%CI, 1.03-1.28), diabetes mellitus (HR, 1.13; 95%CI, 1.01-1.27), age per year (HR, 1.04; 95%CI, 1.02-1.05), and high body mass index for each kg/m2 (HR, 1.03; 95%CI, 1.02-1.04). The presence of incident HF nearly doubled the mortality risk (HR, 1.67; 95%CI, 1.53-1.81).

CONCLUSIONS

The presence of HF in this cohort was relatively frequent and nearly doubled the mortality risk. Eleven risk factors for HF were identified, expanding the scope for primary prevention among elderly patients with AF.

Serum uric acid and outcome in hospitalized elderly patients with chronic heart failure through the whole spectrum of ejection fraction phenotypes

INTRODUCTION

Elevated serum uric acid (SUA) levels have been associated with poor outcome in patients with heart failure (HF). Uric acid is associated with inflammation and microvascular dysfunction, which may differentially affect left ventricular ejection fraction (EF) phenotypes. We aimed to identify the role of SUA across EF phenotypes in hospitalized elderly patients with chronic HF.

METHODS

We analyzed 1355 elderly patients who were diagnosed with chronic HF. All patients had SUA levels measured within the first 24 h following admission. Patients with left ventricle EF were categorized as having HF with reduced EF (HFrEF, EF < 40%), HF with mid-range EF (HFmrEF, 40%≦LVEF ≦ 49%) or HF with preserved EF (HFpEF, LVEF ≥ 50%). Endpoints were cardiovascular death, HF rehospitalization, and their composite. The median follow-up period was 18 months.

RESULTS

Compared with the lowest SUA quartile, the highest SUA quartile was significantly associated with the endpoints (adjusted HR: 2.404, 95% CI: 1.178-4.906, P = 0.016; HR: 1.418, 95% CI: 1.021-1.971, P = 0.037; HR: 1.439, 95% CI: 1.049-1.972, P = 0.024, respectively). After model adjustment, a significant association of SUA with cardiovascular death and the composite endpoint persisted among HFrEF and HFmrEF patients in the highest SUA quartile (P < 0.05 for all).

CONCLUSIONS

In hospitalized elderly patients with chronic HF, SUA is an independent predictor of adverse outcomes, which can be seen in HFrEF and HFmrEF patients.

Validation of E/e' Using the Index-Beat Method as an Estimate of Left Atrial Pressure in Patients with Atrial Fibrillation

INTRODUCTION

Echocardiographic assessment of diastolic function during atrial fibrillation (AF) remains challenging due to the irregular cardiac cycle length. We sought to assess whether the index-beat method, the beat following two preceding cardiac cycles of equal duration, could provide a more reliable measurement of E/e' (mitral E wave/diastolic tissue Doppler velocity) than the conventional averaging of consecutive beats and hence facilitate the noninvasive estimation of elevated left atrial pressure (LAP) in patients with AF.

METHODS

We prospectively studied 35 patients with persistent AF who had preserved left ventricular ejection fraction and underwent radiofrequency ablation. LAP was measured in conjunction with transseptal puncture during catheter ablation. Echocardiography was performed 24 h before ablation and E/e' was determined using the recommended averaging of 10 beats and the index-beat method, with the observers blinded to the clinical details and LAP measurements.

RESULTS

Correlation analysis showed a strong positive correlation between two methods in terms of both septal E/e' (r = 0.841, p < 0.001) and lateral E/e' (r = 0.930, p < 0.001). Bland-Altman analysis also showed a good agreement between the two measurement methods in terms of E/e'. E/e' determined using both conventional averaging and the index-beat method was significantly correlated with LAP (p < 0.05). After Fisher Z transformation, we found that the index-beat septal E/e' had a better correlation with LAP than did the conventional averaging E/e' (r = 0.736 vs. r = 0.392, Zr = -2.110, p = 0.035). Furthermore, the index-beat method took significantly less time to measure E/e' (mean 33.6 s; 95% confidence intervals [CIs]: 32.1 s-36.2 s) than did conventional averaging method (mean 96.2 s; 95% CI: 90.2 s-102.3 s; p < 0.001). Receiver operating characteristic curve analysis revealed that the optimal cut-off for predicting mean LAP >12 mm Hg was 11 (sensitivity 100%; specificity 77.3%) for index-beat septal E/e' and 16 (sensitivity 61.5%; specificity 95.5%) for index-beat lateral E/e'.

CONCLUSIONS

Good correlations were found between E/e' and LAP in patients with AF, particularly with the index-beat method. Moreover, the index-beat method can easily measure E/e' at an accuracy similar to that for the conventional averaging of consecutive beats, which can therefore be applied to assess the diastolic dysfunction and potentially improve the diagnosis of heart failure in patients with AF.

Experimental study on the effect of chlorhexidine gluconate (CG)-induced atrial fibrillation on renal water and sodium metabolism

To construct an animal model of atrial fibrillation and observe the effect of acute atrial fibrillation on renal water and sodium metabolism in mice. A total of 20 C57 mice were randomly assigned to 2 groups (n = 10/group): control group (CON) and atrial fibrillation group (AF). The mice model of atrial fibrillation was induced by chlorhexidine gluconate (CG) in combination with transesophageal atrial spacing. The urine of the two groups of mice was collected, and then we calculate the urine volume and urine sodium content. The expression of TGF-β and type III collagen in the atrial myocardium of the two groups was detected by immunohistochemistry and Western Blot. The levels of CRP and IL-6 in blood were observed by ELISA, and the NF-κB, TGF-β, collagen type III, AQP2, AQP3, AQP4, ENaC-β, ENaC-γ, SGK1 and NKCC proteins in the kidneys of the two groups of mice was observed by Western Blot. Compared with CON, the expression of TGF-β and type III collagen in the atrial myocardium of the mice in AF were increased, the levels of CRP and IL-6 in the blood in AF were increased, and the renal NF-κB, TGF-β, type III collagen AQP2, AQP3, ENaC-β, ENaC-γ, SGK1 and NKCC protein expression in AF were up-regulated. The level of urine volume and urine sodium content in AF were significantly reduced. In the acute attack of atrial fibrillation, the formation of renal inflammatory response and fibrosis is activated, and the renal water and sodium metabolism is hindered, which is related to the up-regulated of the expressions of renal NKCC, ENaC and AQPs.

H2ARDD score as a feasible predictor of heart failure events in patients with atrial fibrillation: a validation study

It was reported that the H₂ARDD score (organic heart diseases = 2 points, anemia = 1 point, renal dysfunction = 1 point, diabetes = 1 point, and diuretic use = 1point; range 0 to 6 points) may help identify patients with AF at high risk for HF events. However, this score has not been externally validated. The objective of this study was to evaluate the usefulness of H₂ARDD score in predicting HF events in patients with AF. We used a prospective database of patients with AF, and Cox-proportional hazards models were used to assess the risk of HF events. The outcome of interest was defined as HF events including new-onset HF and death from HF. Of 562 AF patients, 518 (mean 69.7 ± 9.7 years-old, 64.9% men) met study criteria, and 84 (16.2%) developed HF events during a mean follow-up of 54 ± 42 months. In multivariable analyses, H₂ARDD score was shown as a significant predictor for HF events [hazard ratio (HR): 1.56, 95% confidence interval (CI): 1.36-1.79], independent of age (per 10 years, HR: 1.35, 95% CI: 1.03-1.78). In the Kaplan-Meier analyses stratified by H₂ARDD score categories (0-2, 3-4, 5-6), the patients with higher H₂ARDD scores had significantly worse HF event-free survival (log-rank P < 0.0001). The area under the ROC curve was 0.71 (95% CI: 0.65-0.77, P < 0.0001). The sensitivity and specificity at a cut-off score of ≥ 3 were 60% and 71%, respectively. In conclusion, the H₂ARDD score may be feasible for HF risk stratification in patients with AF.

Comparison of His-Purkinje Conduction System Pacing with Atrial-Ventricular Node Ablation and Pharmacotherapy in HFpEF Patients with Recurrent Persistent Atrial Fibrillation (HPP-AF study)

BACKGROUND

There is currently no particularly effective strategy for patients with persistent atrial fibrillation accompanying heart failure with preserved ejection fraction (HFpEF), especially with recurrent atrial fibrillation after ablation. In this study, we will evaluate a new treatment strategy for patients with persistent atrial fibrillation who had at least two attempts (≧2 times) of radio-frequency catheter ablation but experienced recurrence, and physiologic conduction was reconstructed after atrioventricular node ablation or drug therapy, to control the patient's ventricular rate to maintain a regular heart rhythm, which is called His-Purkinje conduction system pacing (HPCSP) with atrioventricular node ablation.

METHODS AND RESULTS

This investigator-initiated, multicenter prospective randomized controlled trial aimed to recruit 296 randomized HFpEF patients with recurrent atrial fibrillation. All the enrolled patients were randomly assigned to the pacing group or the drug treatment group. The primary endpoint is differences in cardiovascular events and clinical composite endpoints (all-cause mortality) between patients in the HPCSP and drug-treated groups. Secondary endpoints included heart failure hospitalization, exercise capacity assessed by cardiopulmonary exercise tests, quality of life, echocardiogram parameters, 6-minute walk distance, NT-ProBNP, daily patient activity levels, and heart failure management report recorded by the CIED. It is planned to compete recruitment by the end of 2023 and report in 2025.

CONCLUSIONS

The study aims to determine whether His-Purkinje conduction system pacing with atrioventricular node ablation can better improve patients' symptoms and quality of life, postpone the progression of heart failure, and reduce the rate of rehospitalization and mortality of patients with heart failure.

CLINICAL TRIAL REGISTRATION NUMBER

ChiCTR1900027723, URL: http://www.chictr.org.cn/edit.aspx?pid=46128&htm=4.

The Association of Glucose Control with Circulating Levels of Red Blood Cell-Derived Vesicles in Type 2 Diabetes Mellitus Patients with Atrial Fibrillation

Hyperglycemia is a trigger for structural alteration of red blood cells (RBCs) and their ability to release extracellular vesicles (EVs). The aim of the study was to elucidate whether glucose control in T2DM patients with concomitant HF and AF affects a circulating number of RBC-derived EVs. We prospectively included 417 T2DM patients with HF, 51 of them had atrial fibrillation and 25 healthy volunteers and 30 T2DM non-HF individuals. Clinical assessment, echocardiography examination and biomarker measures were performed at the baseline of the study. RBC-derived EVs were determined as CD235a+ PS+ particles by flow cytometry. NT-proBNP levels were measured by ELISA. AF patients with glycosylated hemoglobin (HbA1c) < 6.9% had lower levels of CD235a+ PS+ RBC-derived vesicles than those with HbA1c ≥ 7.0%. There were no significant differences in number of CD235a+ PS+ RBC-derived vesicles between patients in entire cohort and in non-AF sub-cohort with HbA1c < 6.9% and HbA1c ≥ 7.0%, respectively. Multivariate linear regression yielded that CD235a+ PS+ RBC-derived vesicles ≥ 545 particles in µL (OR = 1.06; 95% CI = 1.01−1.11, p = 0.044) independently predicted HbA1c ≥ 7.0%. Elevated levels of CD235a+ PS+ RBC-derived EVs independently predicted poor glycaemia control in T2DM patients with HF and AF.

Impact of heart failure on the clinical profile and outcomes in patients with atrial fibrillation treated with rivaroxaban. Data from the EMIR study

BACKGROUND

The aim of this study was to analyze the impact of the presence of heart failure (HF) on the clinical profile and outcomes in patients with atrial fibrillation (AF) anticoagulated with rivaroxaban.

METHODS

Observational and non-interventional study that included AF adults recruited from 79 Spanish centers, anticoagulated with rivaroxaban ≥ 6 months before inclusion. Data were analyzed according to baseline HF status.

RESULTS

Out of 1,433 patients, 326 (22.7%) had HF at baseline. Compared to patients without HF, HF patients were older (75.3 ± 9.9 vs. 73.8 ± 9.6 years; p = 0.01), had more diabetes (36.5% vs. 24.3%; p < 0.01), coronary artery disease (28.2% vs. 12.9%; p < 0.01), renal insufficiency (31.7% vs. 22.6%; p = 0.01), higher CHA2DS2-VASc (4.5 ± 1.6 vs. 3.2 ± 1.4; p < 0.01) and HAS-BLED (1.8 ± 1.1 vs. 1.5 ± 1.0; p < 0.01). After a median follow-up of 2.5 years, among HF patients, annual rates of stroke/systemic embolism/transient ischemic attack, major adverse cardiovascular events (MACE) (non-fatal myocardial infarction, revascularization and cardiovascular death), cardiovascular death, and major bleeding were 1.2%, 3.0%, 2.0%, and 1.4%, respectively. Compared to those patients without HF, HF patients had greater annual rates of MACE (3.0% vs. 0.5%; p < 0.01) and cardiovascular death (2.0% vs. 0.2%; p < 0.01), without significant differences regarding other outcomes, including thromboembolic or bleeding events. Previous HF was an independent predictor of MACE (odds ratio 3.4; 95% confidence interval 1.6-7.3; p = 0.002) but not for thromboembolic events or major bleeding.

CONCLUSIONS

Among AF patients anticoagulated with rivaroxaban, HF patients had a worse clinical profile and a higher MACE risk and cardiovascular mortality. HF was independently associated with the development of MACE, but not with thromboembolic events or major bleeding.

Fibrillation cycle length predicts cardiovascular events in patients with long-standing persistent atrial fibrillation

BACKGROUND

Atrial fibrillation (AF) is associated with an increased risk of heart failure (HF), stroke, and death. Although fibrillation cycle length (FCL) is used as a surrogate for atrial refractoriness, its impact on outcomes remains unclear. This study aimed to identify predictors of cardiovascular events, including FCL, in patients with long-standing persistent AF.

METHODS

The study included 190 consecutive patients with long-standing persistent AF (mean age 74 years, 74% male). Patients with valvular AF or hemodialysis-dependent end-stage renal disease and those on anti-arrhythmic drugs were excluded. The primary composite outcome was occurrence of cardiovascular events (myocardial infarction, HF), cerebrovascular events (stroke, transient ischemic attack), and all-cause death. FCL was calculated by fast Fourier transformation analysis of fibrillation waves in the surface electrocardiogram.

RESULTS

Over a median follow-up of 2.6 years, the primary outcome occurred in 31 patients (cardiovascular events, n = 18; cerebrovascular events, n = 8; all-cause death, n = 5). In multivariate analysis, longer FCL and history of HF were independent predictors of these outcomes. In a Cox proportional hazards model adjusted for age, sex, and history of HF, patients with an FCL > 160 ms (cut-off determined by receiver-operating characteristic curve analysis) were at increased risk of the outcome (hazard ratio 12.9; 95% confidence interval 4.99-44.10; p < 0.001).

CONCLUSIONS

FCL was independently associated with cardiovascular outcomes in patients with long-standing persistent AF.

Cardiac Conduction Velocity, Remodeling and Arrhythmogenesis

Cardiac electrophysiological disorders, in particular arrhythmias, are a key cause of morbidity and mortality throughout the world. There are two basic requirements for arrhythmogenesis: an underlying substrate and a trigger. Altered conduction velocity (CV) provides a key substrate for arrhythmogenesis, with slowed CV increasing the probability of re-entrant arrhythmias by reducing the length scale over which re-entry can occur. In this review, we examine methods to measure cardiac CV in vivo and ex vivo, discuss underlying determinants of CV, and address how pathological variations alter CV, potentially increasing arrhythmogenic risk. Finally, we will highlight future directions both for methodologies to measure CV and for possible treatments to restore normal CV.

Characteristics and Treatment of Atrial Fibrillation with Respect to the Presence or Absence of Heart Failure. Insights from the Multicenter Polish Atrial Fibrillation (POL-AF) Registry

Background: We aimed to assess characteristics and treatment of AF patients with and without heart failure (HF). Methods: The prospective, observational Polish Atrial Fibrillation (POL-AF) Registry included consecutive patients with AF hospitalized in 10 Polish cardiology centers in 2019–2020. Results: Among 3999 AF patients, 2822 (71%) had HF (AF/HF group). Half of AF/HF patients had preserved ejection fraction (HFpEF). Compared to patients without HF (AF/non–HF), AF/HF patients were older, more often male, more often had permanent AF, and had more comorbidities. Of AF/HF patients, 98% had class I indications to oral anticoagulation (OAC). Still, 16% of patients were not treated with OAC at hospital admission, and 9%—at discharge (regardless of the presence of HF and its subtypes). Of patients not receiving OAC upon admission, 61% were prescribed OAC (most often apixaban) at discharge. AF/non–HF patients more often converted from AF at admission to sinus rhythm at discharge compared to AF/HF patients (55% vs. 30%), despite cardioversion performed as often in both groups. Class I antiarrhythmics were more often prescribed in AF/non–HF than in AF/HF group (13% vs. 8%), but still as many as 15% of HFpEF patients received them. Conclusions: Over 70% of hospitalized AF patients have coexisting HF. A significant number of AF patients does not receive the recommended OAC.

Interleukin-6 Could Be a Potential Prognostic Factor in Ambulatory Elderly Patients with Stable Heart Failure: Results from a Pilot Study

INTRODUCTION

Inflammation is a fundamental phenomenon in heart failure, but the prognostic or therapeutic role of markers such as interleukin-6 (IL-6) has not yet been clarified. The objective of this study is to describe the clinical profile of patients with elevated IL-6 and determine if they have worse clinical outcomes.

METHODS

A retrospective c.ohort observational study including 78 patients with heart failure followed up at the Heart Failure Outpatient Clinic of the Internal Medicine Department. IL-6 was determined in all patients, who were then assigned into two groups according to IL-6 level (normal or high). Clinical and prognostic data were collected to determine the differences in both groups.

RESULTS

The average age was 79 years, 60% female. A total of 53.8% of the patients had elevated IL-6 (group 2). Patients with elevated IL-6 presented more frequently with anemia mellitus (64.3% vs. 41.7%; p = 0.046), atrial fibrillation (83.3% vs. 61.9% p = 0.036), dyslipidemia (76.2% vs. 58.2%; p = 0.03), higher creatinine levels (1.35 mg/dL vs. 1.08 mg/dL; p = 0.024), lower glomerular filtration rate (43.6 mL/min/m2 vs. 59.9 mL/min/m2; p = 0.007), and anemia 25% vs. 52.4% p = 0.014. The factors independently associated with the increase in IL-6 were anemia 3.513 (1.163-10.607) and renal failure 0.963 (0.936-0.991), p < 0.05. Mortality was higher in the group with elevated IL-6 levels (16% vs. 2%; p = 0.044) with a log-rank p = 0.027 in the Kaplan-Meier curve.

CONCLUSION

Patients with heart failure and elevated IL-6 most often have atrial fibrillation, diabetes mellitus, dyslipidemia, anemia, and renal failure. In addition, mortality was higher and a tendency of higher hospital admission was observed in stable HF patients with elevated IL-6.