Atrial fibrillation in heart failure: epidemiology, pathophysiology, and rationale for therapy

Predictors of Higher Frequency of Atrial Fibrillation in Patients with Cardiac Resynchronization Therapy

Background and Objectives: Cardiac resynchronization therapy (CRT) is one of the effective therapeutic options in the treatment of systolic heart failure (HF) with persistent symptoms. This prospective study was designed to determine whether CRT with biventricular pacing would reduce the risk of development of atrial fibrillation (AF) and to identify predictors for AF occurrence. Materials and Methods: The study population consisted of 126 patients, with a mean age of 63.8 ± 9.1 years, who were eligible for CRT with biventricular pacing. Inclusion criteria were left ventricular ejection fraction (LVEF) ≤ 35%, QRS duration ≥ 130 msec, and persistent HF symptoms of New York Heart Association (NYHA) II or III, despite optimal drug therapy. Patients were followed for a period of 24 months and were evaluated through clinical, electrocardiographic, and echocardiographic examination at baseline (prior to CRT implantation), as well as at 6 and 24 months post-implantation. At the end of follow-up, patients were divided into clinical responders and non-responders based on the following criteria: decrease in NYHA class ≥ I, increase in LVEF ≥ 10%, and reduction in QRS duration ≥ 20 msec. Results: At follow-up, CRT was associated with a significant increase in LVEF (20.6 ± 6.9% pre-implantation, 32.9 ± 9.3% 24 months after implantation; p < 0.001), reduction in left ventricular end-diastolic and end-systolic diameters, and decrease in QRS duration (167.6 ± 14.3 msec pre-implantation, 131.7 ± 11.7 msec 24 months after implantation; p < 0.001), while left atrial (LA) diameter was slightly increased (p = 0.070). The frequency of AF occurrence increased after two years of follow-up (52.4% to 56.9%, p < 0.001). Significant predictors of AF occurrence in our study population were response to CRT-AF more frequent in non-responders (B = 8.134; p < 0.001), LA diameter-AF more frequent with larger LA diameter (B = 0.813; p < 0.001), and coronary sinus (CS) lead position-AF more frequent with posterolateral in comparison with lateral CS lead position (B = 5.159; p = 0.005). Conclusions: The results of our study provide new data on AF predictors in patients with HF subjected to CRT. There remains a permanent need for new predictors, which might help in patient selection and improvement in response rate.

Observational Study of the Association between Atrial Fibrillation and In-Hospital Mortality during Hospitalization for Solid Organ Transplants in Spain from 2004 to 2021

(1) Background: We analyzed the association between atrial fibrillation or atrial flutter (AF) and in-hospital mortality (IHM) among patients who underwent solid organ transplants in Spain from 2004 to 2021. (2) Methods: We gathered information from all hospital admissions for lung, liver, kidney, and heart transplants. (3) Results: A total of 71,827 transplants were analyzed (4598 lung transplants; 18,127 liver transplants; 45,262 kidney transplants; and 4734 heart transplants). One third of these were for women. Overall, the prevalence of AF was 6.8% and increased from 5.3% in 2004-2009 to 8.6% in 2016-2021. The highest prevalence of AF was found for heart transplants (24.0%), followed by lung transplants (14.7%). The rates for kidney and liver transplants were 5.3% and 4.1%, respectively. The AF code increased over time for all of the transplants analyzed (p < 0.001). The patients' IHM decreased significantly from 2004-2009 to 2016-2021 for all types of transplants. AF was associated with a higher IHM for all of the types of transplants analyzed, except for heart transplants. (4) Conclusions: The prevalence of AF among patients admitted for solid organ transplants was highest for those who underwent heart transplants. The mortality rate during the patients' admission for lung, liver, kidney, or heart transplants decreased over time. AF was independently associated with a higher risk of dying in the hospital for those who underwent lung, liver, or kidney transplants.

New onset heart failure with reduced ejection fraction management: single center, real-life Tunisian experience

BACKGROUND

Heart failure (HF) is a serious and frequent pathology. It represents a major public health problem. We have few data about this pathology in our country. The aim of our study is to determine the epidemiological, clinical, therapeutic, and prognostic characteristics of new-onset HF with reduced left ventricular ejection fraction (HFrEF) and to study the degree of conformity of the management of HF with international recommendations.

RESULTS

Our study population includes 210 patients hospitalized for HFrEF newly diagnosed. The average age of our patients was 64 ± 12 years. A male predominance was noted with a sex ratio of 2.8. The main etiology of HF was ischemic heart disease noted in 97 patients (46.2%). The average LVEF is 33 ± 6%. The triple combination (angiotensin-converting enzyme inhibitors + beta blockers + Mineralocorticoid Receptor Antagonists) was prescribed in 75 patients (35.7%). The quadruple combination (angiotensin-converting enzyme inhibitors + beta blockers + Mineralocorticoid Receptor Antagonists + Sodium-Glucose Co-Transporter 2 inhibitors) was prescribed in 17 patients (8.1%). Myocardial revascularization was indicated in 97 patients (46.6%) and valve surgery was indicated in 49 patients (23.3%). Hospital mortality was 3.8% and at 1 year 18.1%. Among the 192 patients followed during the first year after discharge from hospital, 81 patients had to be re-hospitalized, i.e., a 1-year rehospitalization rate of 42.2%.

CONCLUSIONS

Our study highlighted the epidemiological and clinical features of HF in a Tunisian care center, revealing our patient management deficiency. This pushes us to have a new Tunisian register to enable a better statistical analysis and lead to more relevant conclusions.

Factors Associated With Maintenance of an Improved Ejection Fraction: An Echocardiogram-Based Registry Study

Background Heart failure with improved ejection fraction (EF) is increasingly recognized as a sizable and distinct entity. While the features associated with improvedEF have been explored and new guidelines have emerged, factors associated with sustaining an improved EF over time have not been defined. We aimed to assess factors associated with maintenance of an improved EF in a large real-world patient cohort. Methods and Results A total of 7070 participants with heart failure with improved EF and a subsequent echocardiogram performed after at least 9 months of follow-up were included in a retrospective cohort study conducted at the Cleveland Clinic in Cleveland, Ohio. Multiple logistic regression models, adjusted for demographics, comorbidities, and medications were built to identify characteristics and therapeutic interventions associated with maintaining an improved EF. Mean age (SD) was 64.9 (13.8) years, 62.7% were men, and 75.1% were White participants. White race and the use of angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, or angiotensin receptor-neprilysin inhibitors were associated with maintaining the EF at least 9 months after EF improvement. In contrast, male sex or having atrial fibrillation/flutter, coronary artery disease, history of myocardial infarction, presence of an implanted cardioverter-defibrillator, and use of loop diuretics were associated with a decline in EF after previously documented improvement. Conclusions Continued use of renin-angiotensin-aldosterone system inhibitors was associated with maintaining the EF beyond the initial improvement phase.

Effect of Carvedilol vs Metoprolol on Atrial and Ventricular Arrhythmias Among Implantable Cardioverter-Defibrillator Recipients

BACKGROUND

Both selective and nonselective beta-blockers are used to treat patients with heart failure (HF). However, the data on the association of beta-blocker type with risk of atrial arrhythmia and ventricular arrhythmia (VA) in HF patients with a primary prevention implantable cardioverter-defibrillator (ICD) are limited.

OBJECTIVES

This study sought to evaluate the effect of metoprolol vs carvedilol on the risk of atrial tachyarrhythmia (ATA) and VA in HF patients with an ICD.

METHODS

This study pooled primary prevention ICD recipients from 5 landmark ICD trials (MADIT-II, MADIT-CRT, MADIT-RIT, MADIT-RISK, and RAID). Fine and Gray multivariate regression models, stratified by study, were used to evaluate the risk of ATA, inappropriate ICD shocks, and fast VA (defined as ventricular tachycardia ≥200 beats/min or ventricular fibrillation) by beta-blocker type.

RESULTS

Among 4,194 patients, 2,920 (70%) were prescribed carvedilol and 1,274 (30%) metoprolol. The cumulative incidence of ATA at 3.5 years was 11% in patients treated with carvedilol vs 15% in patients taking metoprolol (P = 0.003). Multivariate analysis showed that carvedilol treatment was associated with a 35% reduction in the risk of ATA (HR: 0.65; 95% CI: 0.53-0.81; P < 0.001) when compared to metoprolol, and with a corresponding 35% reduction in the risk of inappropriate ICD shocks (HR: 0.65; 95% CI: 0.47-0.89; P = 0.008). Carvedilol vs metoprolol was also associated with a 16% reduction in the risk of fast VA. However, these findings did not reach statistical significance (HR: 0.84; 95% CI: 0.70-1.02; P = 0.085).

CONCLUSIONS

These findings suggests that HF patients with ICDs on carvedilol treatment experience a significantly lower risk of ATA and inappropriate ICD shocks when compared to treatment with metoprolol.

The Relationship Between Atrial Fibrillation and Parathyroid Hormone in Heart Failure Outpatients

Background    Atrial fibrillation (AF) is a common arrhythmia in heart failure (HF). Plasma concentrations of para-thyroid hormone (PTH) have been shown to increase in HF. The relationship between PTH concentrations and the presence of AF in HF is, however, unknown. This study analyzed the relationship between plasma PHT concentrations and AF in patients with systolic HF.Material and methods    131 consecutive, stable HF patients, who were admitted to the HF outpatient clinic, were included in this prospective, observational study. Patients were classified as those with AF (n = 36) and those in sinus rhythm (SR, n = 95).Results    PTH concentrations were markedly higher in patients with AF compared to the patients in SR [85 (15-320) vs. 112 (30-326) U / ml, p=0.007]. PTH, creatinine clearance, hemoglobin, creatinine, age, and left ventricular ejection fraction were found to be related to AF by univariate analysis; though, multivariate logistic regression analysis showed that only PTH concentration was independently related to AF.Conclusion    PTH concentrations can be used to indicate AF in patients with systolic HF.

Diagnostic Value of a Wearable Continuous Electrocardiogram Monitoring Device (AT-Patch) for New-Onset Atrial Fibrillation in High-Risk Patients: Prospective Cohort Study

BACKGROUND

While conventional electrocardiogram monitoring devices are useful for detecting atrial fibrillation, they have considerable drawbacks, including a short monitoring duration and invasive device implantation. The use of patch-type devices circumvents these drawbacks and has shown comparable diagnostic capability for the early detection of atrial fibrillation.

OBJECTIVE

We aimed to determine whether a patch-type device (AT-Patch) applied to patients with a high risk of new-onset atrial fibrillation defined by the congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, stroke, vascular disease, age 65-74 years, sex scale (CHA2DS2-VASc) score had increased detection rates.

METHODS

In this nonrandomized multicenter prospective cohort study, we enrolled 320 adults aged ≥19 years who had never experienced atrial fibrillation and whose CHA2DS2-VASc score was ≥2. The AT-Patch was attached to each individual for 11 days, and the data were analyzed for arrhythmic events by 2 independent cardiologists.

RESULTS

Atrial fibrillation was detected by the AT-Patch in 3.4% (11/320) of patients, as diagnosed by both cardiologists. Interestingly, when participants with or without atrial fibrillation were compared, a previous history of heart failure was significantly more common in the atrial fibrillation group (n=4/11, 36.4% vs n=16/309, 5.2%, respectively; P=.003). When a CHA2DS2-VASc score ≥4 was combined with previous heart failure, the detection rate was significantly increased to 24.4%. Comparison of the recorded electrocardiogram data revealed that supraventricular and ventricular ectopic rhythms were significantly more frequent in the new-onset atrial fibrillation group compared with nonatrial fibrillation group (3.4% vs 0.4%; P=.001 and 5.2% vs 1.2%; P<.001), respectively.

CONCLUSIONS

This study detected a moderate number of new-onset atrial fibrillations in high-risk patients using the AT-Patch device. Further studies will aim to investigate the value of early detection of atrial fibrillation, particularly in patients with heart failure as a means of reducing adverse clinical outcomes of atrial fibrillation.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04857268; https://classic.clinicaltrials.gov/ct2/show/NCT04857268.

Use of SGLT2i and ARNi in patients with atrial fibrillation and heart failure in 2021-2022: an analysis of real-world data

Objective

To evaluate utilization of sodium-glucose cotransporter-2 inhibitors (SGLT2i) and angiotensin receptor neprilysin inhibitors (ARNi) in patients with atrial fibrillation (AF) and heart failure (HF).

Methods

We analyzed the MarketScan databases for the period 1/1/2021 to 6/30/2022. Validated algorithms were used to identify patients with AF and HF, and to classify patients into HF with reduced ejection fraction (HFrEF) or preserved ejection fraction (HFpEF). We assessed the prevalence of SGLT2i and ARNi use overall and by HF type. Additionally, we explored correlates of lower utilization, including demographics and comorbidities.

Results

The study population included 60,927 patients (mean age 75, 43% female) diagnosed with AF and HF (85% with HFpEF, 15% with HFrEF). Prevalence of ARNi use was 11% overall (30% in HFrEF, 8% in HFpEF), while the corresponding figure was 6% for SGLT2i (13% in HFrEF, 5% in HFpEF). Use of both medications increased over the study period: ARNi from 9% to 12% (from 22% to 29% in HFrEF, from 6% to 8% in HFpEF), and SGLT2i from 3% to 9% (from 6% to 16% in HFrEF, from 2% to 7% in HFpEF). Female sex, older age, and specific comorbidities were associated with lower utilization of these two medication types overall and by HF type.

Conclusion

Use of ARNi and SGLT2i in patients with AF and HF is suboptimal, particularly among females and older individuals, though utilization is increasing. These results underscore the need for understanding reasons for these disparities and developing interventions to improve adoption of evidence-based therapies among patients with comorbid AF and HF.

Association of Atrial Fibrillation Recurrence with Right Coronary Atherosclerosis and Increased Left Arterial Epicardial Fat Following Catheter Ablation-Results of a Multimodality Study

BACKGROUND

Identification of predictors for atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI) can lead to better long-term results. Our aim was to investigate the association between novel CT imaging markers reflecting the severity of coronary atherosclerosis and the risk of recurrence following PVI.

METHODS

This study included 80 patients with paroxysmal/persistent AF who underwent PVI. The patients were divided into two groups: Group 1-23 patients with recurrence and Group 2-57 patients without recurrence.

RESULTS

Patients with recurrence presented with a more enlarged left atrial diameter and reduced left ventricle EF, as assessed by echocardiography. Elevated calcium scores and right coronary artery (RCA) stenosis were correlated with a higher risk of AF recurrence (25.38 ± 4.1% vs. 9.76 ± 2.32%, p = 0.001). Patients with AF recurrence presented a higher left atrial volume index (LAVI) (61.38 ± 11.12 mm3/m2 vs. 46.34 ± 12.27 mm3/m2, p < 0.0001). The bi-atrial volume index (BAVI) was similarly higher in the AF recurrence group (98.23 ± 14.44 mm3/m2 vs. 76.48 ± 17.61 mm3/m2, p < 0.0001). Increased EAT volumes located around the LA (EAT-LA) were correlated with recurrence (25.55 ± 6.37 vs. 15.54 ± 8.44, p < 0.0001).

CONCLUSIONS

RCA stenosis, together with atrial volumes and EAT-AS evaluated by CCTA, is associated with the risk of AF recurrence following PVI.

Particularities of coronary physiology in patients with atrial fibrillation: insights from combined pressure and flow indices measurements

Background

Symptoms suggestive of myocardial ischemia are frequently encountered in patients with atrial fibrillation (AF) even in the absence of obstructive coronary artery disease. Nevertheless, an in-depth characterisation of coronary physiology in patients with AF is currently lacking.

Objectives

We aim to provide an insight into the characteristics of coronary physiology in AF, by performing simultaneous invasive measurements of coronary flow- and pressure- indices in a real-life population of patients with AF and indication of coronary angiography.

Methods

This is a prospective open label study including patients with permanent or persistent AF and indication of coronary angiography showing intermediate coronary stenosis requiring routine physiological assessment (n = 18 vessels from 14 patients). We measured FFR (fractional flow reserve), and Doppler-derived coronary flow indices, including CFR (coronary flow reserve) and HMR (hyperaemic microvascular resistance).

Results

From the analysed vessels, 18/18 vessels (100%) presented a pathological CFR (<2.5), indicative of coronary microvascular dysfunction (CMD), and 3/18 (17%) demonstrated obstructive epicardial coronary disease (FFR ≤ 0.8). A large proportion of vessels (15/18; 83%) showed discordant FFR/CFR with preserved FFR and low CFR. 47% of the coronary arteries in patients with AF and non-obstructive epicardial coronary disease presented structural CMD (HMR ≥ 2.5 mmHg/cm/s), and were associated with high BMR and an impaired response to adenosine. Conversely, vessels from patients with AF and non-obstructive epicardial coronary disease with functional CMD (HMR < 2.5 mmHg/cm/s) showed higher bAPV. The permanent AF subpopulation presented increased values of HMR and BMR compared to persistent AF, while structural CMD was more often associated with persistent symptoms at 3 months, taking into account the limited sample size of our study.

Conclusion

Our findings highlight a systematically impaired CFR in patients with AF even in the absence of obstructive epicardial coronary disease, indicative of CMD. In addition, patients with AF presented more prevalent structural CMD (HMR ≥ 2.5 mmHg/cm/s), characterized by reduced hyperaemic responses to adenosine, possibly interfering with the FFR assessment.

SE-ResNet-ViT Hybrid Model for Noise Classification in Adhesive Patch-type Wearable Electrocardiographs

In purpose of screening arrhythmia, wearable adhesive patch-type electrocardiographs that can measure electrocardiogram continuously for 14 days have been replacing the 24-hour Holter monitor. The reason for that is the patch-type electrocardiograph being smaller and lighter than the Holter monitor, making it more convenient for patients to coexist with in their daily lives. However, this type of electrocardiograph generates a lot of noise signals due to movements during various physical activities and extended wear time.While analyzing electrocardiograms automatically using software, noise signals make the analysis difficult and they may be misclassified as arrhythmia signals. These misclassified signals require a lot of effort and time from clinical technicians to reclassify them as noise. To resolve this problem, this study hypothesized that a deep learning algorithm could be used to screen noise signals. We used 7,467 noise signals and 15,638 ECG signals collected from arrhythmia patients and healthy people. The signals were divided into 10 seconds segments and labeled by cardiologists. We split the data into training and test datasets, ensuring no patient overlap.A hybrid noise classification model, Squeeze and Excitation - Residual Network - Vision Transformer (SE-ResNet-ViT) was developed using the training and validation datasets with an 8:2 ratio. We evaluated the performance of the model using a test dataset. The best F1 score was 0.964. The proposed model can effectively screen for noise signals and potentially reducing the time and effort required by clinical technicians.

Should atrial fibrillation be considered a vascular disease? The need for a comprehensive vascular approach

INTRODUCTION

Atrial fibrillation (AF) cannot be considered an isolated disease. Patients with AF should be managed using a comprehensive approach that is not limited to stroke prevention.

AREAS COVERED

In this manuscript, the potential role of AF as a vascular disease that is managed as part of a holistic approach was reviewed.

EXPERT OPINION

The residual risk of stroke in patients with AF reaches 1-2% annually, despite appropriate anticoagulation therapy. Additionally, patients with AF may develop cognitive impairment through stroke-independent pathways. Furthermore, patients with AF may have a higher risk of developing atherosclerotic vascular disease in various vascular beds and chronic kidney disease; conversely, patients with atherosclerotic disease may have an increased risk of developing AF. AF should be considered a truly systemic vascular disease, since it brings together several hemodynamic and systemic changes, including inflammation, oxidative stress, activation of the renin-angiotensin-aldosterone and sympathetic systems, as well as a prothrombotic state and endothelial dysfunction. In this regard, patients with AF should be treated based on a holistic approach that is not limited to oral anticoagulation but includes complete vascular protection.

Genomic approaches to identify and investigate genes associated with atrial fibrillation and heart failure susceptibility

Atrial fibrillation (AF) and heart failure (HF) contribute to about 45% of all cardiovascular disease (CVD) deaths in the USA and around the globe. Due to the complex nature, progression, inherent genetic makeup, and heterogeneity of CVDs, personalized treatments are believed to be critical. To improve the deciphering of CVD mechanisms, we need to deeply investigate well-known and identify novel genes that are responsible for CVD development. With the advancements in sequencing technologies, genomic data have been generated at an unprecedented pace to foster translational research. Correct application of bioinformatics using genomic data holds the potential to reveal the genetic underpinnings of various health conditions. It can help in the identification of causal variants for AF, HF, and other CVDs by moving beyond the one-gene one-disease model through the integration of common and rare variant association, the expressed genome, and characterization of comorbidities and phenotypic traits derived from the clinical information. In this study, we examined and discussed variable genomic approaches investigating genes associated with AF, HF, and other CVDs. We collected, reviewed, and compared high-quality scientific literature published between 2009 and 2022 and accessible through PubMed/NCBI. While selecting relevant literature, we mainly focused on identifying genomic approaches involving the integration of genomic data; analysis of common and rare genetic variants; metadata and phenotypic details; and multi-ethnic studies including individuals from ethnic minorities, and European, Asian, and American ancestries. We found 190 genes associated with AF and 26 genes linked to HF. Seven genes had implications in both AF and HF, which are SYNPO2L, TTN, MTSS1, SCN5A, PITX2, KLHL3, and AGAP5. We listed our conclusion, which include detailed information about genes and SNPs associated with AF and HF.

Epidemiology, Trends, Utilization Disparities, and Outcomes of Catheter Ablation and Its Association With Coronary Vasospasm Amongst Patients With Non-valvular Atrial Fibrillation: A Nationwide Burden of Last Decade

BACKGROUND

Catheter ablation (CA) is an important curative treatment for non-valvular atrial fibrillation (NVAF), however, nationwide data on its utilization and disparities is limited. Coronary vasospasm is a rare, life-threatening, peri-operative complication of CA with limited literature in Caucasians.

METHODS

We performed a retrospective study on adult hospitalizations in the USA from 2007 to 2017 by obtaining the data from National Inpatient Sample. The primary endpoints of our study were to identify the utilization rate of CA, disparities in utilization, and study the outcomes associated with CA. The secondary endpoints of the study were to identify the incidence of coronary vasospasm amongst patients who underwent CA, evaluate their association, and identify the predictors of coronary vasospasm.

RESULTS

From 35,906,946 patients with NVAF, 343641 (0.96%) underwent CA. Its utilization decreased from 1% in 2007 to 0.71% in 2017. Patients who underwent CA, compared to those without CA, fared better in terms of hospital length of stay, mortality rate, disability rate, and discharge to the non-home facility. Patients in the 50-75 years age group, Native Americans, those with private insurance, and median household income of 76-100th percentile were associated with higher odds of CA utilization. Urban teaching hospitals and large-bedded hospitals performed more ablations, while the Mid-West region fared lower than the South, the West, and the Northeast. The prevalence of coronary vasospasm was higher amongst CA in comparison without CA, however, in regression analysis, no significant association was demonstrated between CA and coronary vasospasm.

CONCLUSION

CA is an important treatment modality that is associated with improved clinical outcomes. Identification of factors associated with lower utilization of CA and its disparities will help to mitigate the burden associated with NVAF.

Heart failure with reduced ejection fraction and atrial fibrillation: a Sub-Saharan African perspective

Cardiovascular diseases are a well-established cause of death in high-income countries. In the last 20 years, Sub-Saharan Africa (SSA) has seen one of the sharpest increases in cardiovascular disease-related mortality, superseding that of infectious diseases, including HIV/AIDS, in South Africa. This increase is evidenced by a growing burden of heart failure and atrial fibrillation (AF) risk factors. AF is a common comorbidity of heart failure with reduced ejection fraction (HFrEF), which predisposes to an increased risk of stroke, rehospitalizations, and mortality compared with patients in sinus rhythm. AF had the largest relative increase in cardiovascular disease burden between 1990 and 2010 in SSA and the second highest (106.4%) increase in disability-adjusted life-years (DALY) between 1990 and 2017. Over the last decade, significant advancements in the management of both HFrEF and AF have emerged. However, managing HFrEF/AF remains a clinical challenge for physicians, compounded by the suboptimal efficacy of guideline-mandated pharmacotherapy in this group of patients. There may be an essential role for racial differences and genetic influence on therapeutic outcomes of HFrEF/AF patients, further complicating our overall understanding of the disease and its pathophysiology. In SSA, the lack of accurate and up-to-date epidemiological data on this subgroup of patients presents a challenge in our quest to prevent and reduce adverse outcomes. This narrative review provides a contemporary overview of the epidemiology of HFrEF/AF in SSA. We highlight important differences in the demographic and aetiological profile and the management of this subpopulation, emphasizing what is currently known and, more importantly, what is still unknown about HFrEF/AF in SSA.

A Case of Non-Tachycardic Atrial Fibrillation Whose Left Ventricular Systolic Dysfunction Improved After Catheter Ablation

It is difficult to identify the causes and optimal treatment of heart failure (HF) in patients with atrial fibrillation (AF) and HF with reduced ejection fraction (EF) (HFrEF). Tachyarrhythmia can cause left ventricular (LV) systolic dysfunction called tachycardia-induced cardiomyopathy (TIC). In patients with TIC, conversion to sinus rhythm may lead to improvement in LV systolic dysfunction. However, it is unclear whether we should try to convert patients with AF without tachycardia to sinus rhythm. A 46-year-old man with chronic AF and HFrEF came to our hospital. His New York Heart Association (NYHA) classification was class II. The blood test showed a brain natriuretic peptide of 105 pg/mL. Electrocardiogram (ECG) and 24-h ECG showed AF without tachycardia. Transthoracic echocardiography (TTE) showed left atrial (LA) dilatation, LV dilatation, and diffuse LV hypokinesis (EF was 40%). Although he was optimized medically, NYHA classification II persisted. Therefore, he underwent direct current cardioversion and catheter ablation. After his AF converted to a sinus rhythm of heart rate (HR) 60 - 70 beats per minute (bpm), TTE showed improvement in LV systolic dysfunction. We gradually reduced oral medications for arrhythmia and HF. We subsequently succeeded in discontinuing all medications 1 year after catheter ablation. TTE performed between 1 and 2 years after catheter ablation showed normal LV function and normal cardiac size. During the 3 years of follow-up, there was no recurrence of AF, and he was not readmitted to the hospital. This patient showed the effectiveness of converting AF to sinus rhythm in patients without tachycardia.

Do Elderly Patients with Heart Failure and Reduced Ejection Fraction Benefit from Pharmacological Strategies for Prevention of Arrhythmic Events?

BACKGROUND

Heart failure is associated with aging. It is one of the leading causes of morbidity and mortality in Western countries and constitutes the main cause of hospitalization among elderly patients. The pharmacological therapy of patients with heart failure with reduced ejection fraction (HFrEF) has greatly improved during the last years. However, elderly patients less frequently receive recommended medical treatment.

SUMMARY

The quadruple therapy (sacubitril/valsartan, beta-blockers, mineralocorticoid receptor antagonists, and sodium-glucose cotransporter 2 inhibitors) is nowadays the cornerstone of medical treatment since it associates lower risk of heart failure hospitalizations and mortality (also of arrhythmic origin). Cardiac arrhythmias, including sudden cardiac death, are common in patients with HFrEF, entailing worse prognosis. Previous studies addressing the role of blocking the renin-angiotensin-aldosterone system and beta-adrenergic receptors in HFrEF have suggested different beneficial effects on arrhythmia mechanisms. Therefore, the lower mortality associated with the use of the four pillars of HFrEF therapy depends, in part, on lower sudden (mostly arrhythmic) cardiac death.

KEY MESSAGES

In this review, we highlight and assess the role of the four pharmacological groups that constitute the central axis of the medical treatment of patients with HFrEF in clinical prognosis and prevention of arrhythmic events, with special focus on the elderly patient, since evidence supports that most benefits provided are irrespective of age, but elderly patients receive less often guideline-recommended medical treatment.

Prevalence and Prognostic Implication of Atrial Fibrillation in Heart Failure Subtypes: Systematic Review and Meta-Analysis

BACKGROUND

Atrial fibrillation (AF) and heart failure (HF) portends a poor outcome. The HF universal definition has incorporated Heart Failure with mildly reduced Ejection Fraction (HFmrEF). We sought to evaluate the relationship between AF and different HF subtypes, with emphasis on HFmrEF.

METHODS

PubMed and Embase databases were searched up to July 2022. Studies that classified HF with EF≥50% as Heart Failure with Preserved Ejection Fraction (HFpEF); EF 40%-49% as HFmrEF; and EF <40% as Heart Failure with Reduced Ejection Fraction (HFrEF) were included.

RESULTS

Fifty (50) eligible studies, with 126,720 acute HF and 109,683 chronic HF patients, were included. Ten percent (10%) and 12% of patients constituted HFmrEF subtype in patients with acute and chronic HF, respectively. The AF prevalence was 38% (95%CI [33, 44], I²=96.9%) in HFmrEF, as compared to 43% (95%CI [39, 47], I²=97.9%) in HFpEF, and 32% (95%CI [29, 35], I² =98.6%) in HFrEF in acute HF patients. Meta-regression showed HFmrEF shared age as a determinant for AF prevalence with HFrEF and HFpEF. Similar AF prevalence also was observed in chronic HF. Compared to sinus rhythm, AF was associated with an increased risk of all-cause mortality in all HF subtypes: HFmrEF (n=6; HR 1.28, 95%CI [1.08, 1.51], I²=71%), HFpEF (n=10; HR 1.14, 95%CI [1.06, 1.23], I²=55%) and HFrEF (n=9; HR 1.11, 95%CI [1.02, 1.21], I²=78%).

CONCLUSION

The prevalence of AF was intermediate for HFmrEF in between HFpEF and HFrEF, with determinants shared with either HF subtype. The co-existence of AF and HF predicts an increased all-cause mortality across all categories of HF. (PROSPERO registry: CRD42021189411).

Intracardiac energy inefficiency during atrial fibrillation rhythm with heart failure: Assessment by echo-vector flow mapping

AIMS

Intracardiac dynamics during atrial fibrillation(AF) complicated by heart failure(HF) are not fully understood. The aim of this study was to evaluate the impact of intracardiac dynamics assessed by echo-vector flow mapping on AF complicated by HF.

METHODS AND RESULTS

We enrolled 76 AF patients receiving sinus restoration therapy and assessed energy loss(EL) by echo-vector flow mapping during both AF rhythm and sinus rhythm. Patients were divided into 2 groups according to serum NT-proBNP level: high NT-proBNP group(≥1800 pg/ml during AF rhythm: N = 19), and low NT-proBNP group(N = 57). Outcome measures were average ELs/stroke volume(SV) in left ventricle(LV) and left atrium(LA). Average EL/SVs during AF rhythm in the LV and LA were significantly larger in the high NT-proBNP group than the low NT-proBNP group(54.2 mE/m·L versus 41.2 mE/m·L, P = 0.02; 3.2 mE/m·L versus 1.9 mE/m·L, P = 0.01). The significantly larger EL/SV in the high NT-proBNP group was recorded for maximum EL/SVs. In patients with high NT-proBNP, large vortex formation with extreme EL was detected in the LV and LA during the diastolic phase. After sinus restoration, the average decrease of EL/SV in the LV and LA was larger in the high NT-proBNP group(-21.4 mE/m·L versus +2.6 mE/m·L, P = 0.04; -1.6 mE/m·L versus -0.3 mE/m·L, P = 0.02). Average EL/SV during sinus rhythm did not significantly differ between the high and low NT-proBNP groups in the LV and LA.

CONCLUSIONS

High EL during AF rhythm as intracardiac energy inefficiency was associated with high serum NT-proBNP levels and improved after sinus restoration.

Minimally invasive epicardial left-ventricular lead implantation and simultaneous left atrial appendage closure

Background

Atrial fibrillation (AF) is common in patients with heart failure resulting in a high prevalence of AF in patients receiving Cardiac Resynchronization Therapy (CRT) implantation. In patients, unsuitable for transvenous left ventricular (LV)-lead implantation, epicardial LV-lead implantation represents a valuable alternative. Epicardial LV-lead placement can be achieved totally thoracoscopical or via minimally invasive left lateral thoracotomy. In patients with atrial fibrillation, concomitant left atrial appendage (LAA) clipping is feasible via the same access. Therefore, the aim of our study was the analysis of safety and efficacy of epicardial LV lead implantation and concomitant LAA clipping via minimally invasive left-lateral thoracotomy.

Methods

Between December 2019 and March 2022, 8 patients received minimally invasive left atrial LV-lead implantation with concomitant LAA closure using the AtriClip. Transesophageal echocardiography (TEE) was performed to intraoperatively guide and control LAA closure.

Results

Mean patients age was 64 ± 11.2 years, 67% were male patients. Minimally invasive left-lateral thoracotomy was used in 6 patients while a totally thoracoscopic approach was performed in 2 cases. Epicardial lead implantation was successfully performed in all patients with good pacing threshold (mean 0.8 ± 0.2 V) and sensing values (10.1 ± 2.3 mV). Posterolateral position of the LV lead was achieved in all patients. Furthermore, successful LAA closure was confirmed during TEE in all patients. No procedure-related complications occurred in any of the patients. Two patients additionally received simultaneous laser lead extraction during the same procedure. Complete lead extraction was achieved in both patients. All patients were extubated in the OR and had an uneventful postoperative course.

Conclusion

Our study highlights a novel treatment approach for patients with atrial fibrillation and the necessity of epicardial LV leads. Placement of a posterolateral LV lead position with concomitant occlusion of the left atrial appendage via a minimally-invasive left-lateral thoracotomy or even a totally thoracoscopic approach is safe and feasible with superior cosmetic result and complete occlusion of the left atrial appendage.

Catheter ablation vs. drug therapy in the treatment of atrial fibrillation patients with heart failure: An update meta-analysis for randomized controlled trials

Background

Atrial fibrillation (AF) and heart failure (HF) often coexist. The treatment of AF in patients with HF has been challenging because of the ongoing debate about the merits of catheter ablation vs. drug therapy.

Methods

The Cochrane Library, PubMed, and www.clinicaltrials.gov were searched until June 14, 2022. Inclusion criteria were catheter ablation compared with drug therapy in adults with AF and HF in randomized controlled trials (RCTs). Primary outcomes consisted of all-cause mortality, re-hospitalization, change in left ventricular ejection fraction (LVEF), and AF recurrence. Secondary outcomes referred to quality of life [QoL; measured by the Minnesota Living with Heart Failure Questionnaire (MLHFQ)], six-minute walk distance (6MWD), and adverse events. The PROSPERO registration ID was CRD42022344208.

Findings

In total, nine RCTs with 2,100 patients met the inclusion criteria, with 1,062 for catheter ablation and 1,038 for medication. According to the meta-analysis, catheter ablation significantly reduced all-cause mortality compared with drug therapy [9.2% vs. 14.1%, OR: 0.62, (95% CI: 0.47-0.82), P = 0.0007, I 2   = 0%], improved LVEF [MD: 5.65%, (95% CI: 3.32-7.98), P < 0.00001, I 2   = 86%], reduced AF recurrence [41.6% vs. 61.9%, OR: 0.23, (95% CI: 0.11-0.48), P < 0.0001, I 2   = 82%], decreased the MLHFQ score [MD: -6.38, (95% CI: -11.09 to -1.67), P = 0.008, I2  = 64%] and increased 6MWD [MD: 17.55, (95% CI: 15.77-19.33), P < 0.0001, I 2   = 37%]. Catheter ablation did not increase the re-hospitalization [30.4% vs. 35.5%, OR: 0.68, (95% CI: 0.42-1.10), P = 0.12, I 2   = 73%] and adverse events [31.5% vs. 30.9%, OR: 1.06, (95% CI: 0.83-1.35), P = 0.66, I 2   = 48%].

Interpretation

In AF patients with HF, catheter ablation improves exercise tolerance, QoL, and LVEF and significantly reduced all-cause mortality and AF recurrence. Although the differences were not statistically significant, the study found lower re-hospitalization and approximate adverse events with improved catheter ablation tendency.

PROSPERO registration ID

CRD42022344208.

Relationship between atrial fibrillation and a liver fibrogenesis marker in patients with acute heart failure

BACKGROUND

Hemodynamic disturbance in heart failure (HF) induces extra-cardiac organ injury. Atrial fibrillation (AF) is common in patients with HF. The relationship between AF and organ injury in HF remains unclear. We investigated the relationship between AF and the liver fibrosis marker, type IV collagen 7S (P4NP 7S) in patients with HF.

METHODS AND RESULTS

From a pooled dataset of 3 observational cohorts of hospitalized HF, 720 patients in whom P4NP 7S was measured before discharge were included. Median P4NP 7S were 5.1, 5.3, and 6.2 ng/mL in the sinus rhythm (SR) (n = 368), paroxysmal AF (n = 67), and persistent AF (n = 285) groups, respectively (P < 0.001). In the multiple linear regression analysis, the significant association with P4NP 7S was found for persistent AF (P < 0.001). The cumulative 1-year incidence of the primary composite endpoint of cardiac death and HF hospitalization were 27.6, 24.1, and 34.5% in the SR, paroxysmal AF, and persistent AF groups, respectively (Log-rank P = 0.07) and 25.3 and 34.5% in the low (below median) and high P4NP 7S groups, respectively (Log-rank P = 0.005). The adjusted risks of persistent AF versus SR and high P4NP 7S versus low P4NP 7S for the primary endpoint were 1.38 (95% confidence interval 1.02-1.89) and 1.52 (1.14-2.03), respectively. When patients were divided based on a combination of AF and P4NP 7S, concomitant persistent AF and high P4NP 7S portended a dismal prognosis.

CONCLUSION

AF is associated with an increase in the liver fibrosis marker. Co-presence of persistent AF and P4NP 7S may portend adverse clinical outcomes.

High Burden of Premature Ventricular Complex Increases the Risk of New-Onset Atrial Fibrillation

Background High burden of premature ventricular complex (PVC) leads to increased cardiovascular mortality. A recent nationwide population-based study demonstrated that PVC is associated with an increased risk of atrial fibrillation (AF). However, the relationship between PVC burden and new-onset AF has not been investigated. The purpose of the study is to elucidate whether PVC burden is associated with new-onset AF. Methods and Results We designed a single-center, retrospective, large population-based cohort study to evaluate the role of PVC burden and new-onset AF in Taiwan. Patients who were AF naïve with PVC were divided into the low burden group (<1000/day) and moderate-to-high burden group (≥1000/day) based on the 24-h Holter ECG report. New-onset AF was defined as a new or first detectable event of either a persistent or paroxysmal AF. A total of 16 030 patients who were AF naïve and underwent 24-h Holter ECG monitoring were enrolled in this study, with a mean follow-up time of 973 days. A propensity score-matched analysis demonstrated that the moderate-to-high burden PVC group had a higher risk of developing new-onset AF than that of the low burden PVC group (4.91% versus 2.73%, P<0.001). Multivariate Cox regression analysis showed that moderate-to-high burden of PVC is an independent risk factor for new-onset AF. The Kaplan-Meier analysis demonstrated that patients with moderate-to-high PVC burden were associated with higher risk of new-onset AF (log-rank P<0.001). Conclusions PVC burden is associated with new-onset AF. Patients with moderate-to-high PVC burden are at a higher risk of new-onset AF. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03877614.

Intermedin 1-53 Ameliorates Atrial Fibrosis and Reduces Inducibility of Atrial Fibrillation via TGF-β1/pSmad3 and Nox4 Pathway in a Rat Model of Heart Failure

OBJECTIVE

New drugs to block the occurrence of atrial fibrillation (AF) based on atrial structural remodeling (ASR) are urgently needed. The purpose of this study was to study the role of intermedin 1-53 (IMD1-53) in ASR and AF formation in rats after myocardial infarction (MI).

MATERIAL AND METHODS

Heart failure was induced by MI in rats. Fourteen days after MI surgery, rats with heart failure were randomized into control (untreated MI group, n = 10) and IMD-treated (n = 10) groups. The MI group and sham group received saline injections. The rats in the IMD group received IMD1-53, 10 nmol/kg/day intraperitoneally for 4 weeks. The AF inducibility and atrial effective refractory period (AERP) were assessed with an electrophysiology test. Additionally, the left-atrial diameter was determined, and heart function and hemodynamic tests were performed. We detected the area changes of myocardial fibrosis in the left atrium using Masson staining. To detect the protein expression and mRNA expression of transforming growth factor-β1 (TGF-β1), α-SMA, collagen Ⅰ, collagen III, and NADPH oxidase (Nox4) in the myocardial fibroblasts and left atrium, we used the Western blot method and real-time quantitative polymerase chain reaction (PCR) assays.

RESULTS

Compared with the MI group, IMD1-53 treatment decreased the left-atrial diameter and improved cardiac function, while it also improved the left-ventricle end-diastolic pressure (LVEDP). IMD1-53 treatment attenuated AERP prolongation and reduced atrial fibrillation inducibility in the IMD group. In vivo, IMD1-53 reduced the left-atrial fibrosis content in the heart after MI surgery and inhibited the mRNA and protein expression of collagen type Ⅰ and III. IMD1-53 also inhibited the expression of TGF-β1, α-SMA, and Nox4 both in mRNA and protein. In vivo, we found that IMD1-53 inhibited the phosphorylation of Smad3. In vitro, we found that the downregulated expression of Nox4 was partly dependent on the TGF-β1/ALK5 pathway.

CONCLUSIONS

IMD1-53 decreased the duration and inducibility of AF and atrial fibrosis in the rats after MI operation. The possible mechanisms are related to the inhibition of TGF-β1/Smad3-related fibrosis and TGF-β1/Nox4 activity. Therefore, IMD1-53 may be a promising upstream treatment drug to prevent AF.

Catheter Ablation for Atrial Fibrillation in Structural Heart Disease: A Review

Atrial fibrillation (AF) is the most common arrhythmia encountered in clinical practice. Patients with structural heart disease (SHD) are at an increased risk of developing this arrhythmia and are particularly susceptible to the deleterious hemodynamic effects it carries. In the last two decades, catheter ablation (CA) has emerged as a valuable strategy for rhythm control and is currently part of the standard care for symptomatic relief in patients with AF. Growing evidence suggests that CA of AF may have potential benefits that extend beyond symptoms. In this review, we summarize the current knowledge of this intervention on SHD patients.

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.

Intrinsic Cardiac Neuromodulation in the Management of Atrial Fibrillation- A Potential Missing Link?

Atrial fibrillation (AF) is the most common supraventricular arrhythmia that is linked with higher cardiovascular morbidity and mortality. Recent evidence has demonstrated that catheter-based pulmonary vein isolation (PVI) is not only a viable alternative but may be superior to antiarrhythmic drug therapy for long-term freedom from symptomatic AF episodes, a reduction in the arrhythmia burden, and healthcare resource utilization with a similar risk of adverse events. The intrinsic cardiac autonomic nervous system (ANS) has a significant influence on the structural and electrical milieu, and imbalances in the ANS may contribute to the arrhythmogenesis of AF in some individuals. There is now increasing scientific and clinical interest in various aspects of neuromodulation of intrinsic cardiac ANS, including mapping techniques, ablation methods, and patient selection. In the present review, we aimed to summarize and critically appraise the currently available evidence for the neuromodulation of intrinsic cardiac ANS in AF.

Optimization of pharmacotherapies for ambulatory patients with heart failure and reduced ejection fraction is associated with improved outcomes

BACKGROUND

In heart failure, specific target doses for each drug are recommended, but some patients receive suboptimal dosing, others are undertreated or remain chronically in a titration phase, despite having no apparent contraindication or intolerance. We assessed the association of different levels of adherence to guidelines with outcomes in patients with heart failure and reduced ejection fraction (HFrEF).

METHODS

Medical records of patients with HFrEF followed at our heart failure (HF) clinic for at least 6 months (n = 511) were reviewed and patients categorized as: 1) optimized (25.4%); 2) in-titration (29.0%); 3) undertreated (32.7%); and 4) intolerant/contraindicated (12.9%). Risk of mortality or HF events (hospitalization, emergency visit or ambulatory administration of intravenous diuretics) within one year was assessed using Cox regression models and Kaplan-Meier curves.

RESULTS

Compared to optimized patients, those intolerant (HR: 4.60 [95%CI: 2.23-9.48]; p < 0.0001) had the highest risk of outcomes, followed by those undertreated (3.45 [1.78-6.67]; p = 0.0002) and in-titration (1.99 [0.97-4.06]; p = 0.0588). Overall predictors of outcomes included loop diuretics' use (4.54 [2.39-8.60]), undertreatment (2.38 [1.22-4.67]), intolerance/ contraindication to triple therapy (3.08 [1.47-6.42]), peripheral vascular disease (2.13 [1.29-3.50]) and NYHA class III-IV (1.89 [1.25-2.85]); all p < 0.05.

CONCLUSION

Level of adherence to guidelines is associated with outcomes, with intolerant/contraindicated patients having the worst prognosis and those undertreated and in-titration at intermediate risk compared to those optimized. Up-titration of therapy should be attempted whenever possible, considering patients' limitations, to potentially improve outcomes.

[Tachycardiomyopathy]

Tachycardiomyopathy (TMP) is the development of heart failure due to a cardiac arrhythmia - triggered by rapid and/or irregular ventricular actions. TMP is in principle a (at least partially) reversible disease, so that control of the arrhythmia is of central importance. This article provides an overview of the causes, diagnosis and therapy.

Catheter ablation of atrial fibrillation in heart failure with impaired systolic function: An updated meta-analysis of randomized controlled trials

BACKGROUND

The recent Atrial Fibrillation Management in Congestive Heart Failure With Ablation trial did not reveal any benefit of catheter ablation in patients with atrial fibrillation (AF), advanced heart failure (HF), and severely reduced left ventricular ejection fraction (LVEF). We hypothesized that radiofrequency catheter ablation (RFCA) could improve outcomes in HF patients with AF and impaired left ventricular systolic function (LVEF <50%) as compared with only medical therapy.

METHODS

We searched the literature for randomized clinical trials (RCTs) that compared RFCA to medical therapy in this population.

RESULTS

Compared with the medical therapy group, the RFCA group had significantly less all-cause mortality, HF hospitalization, and AF recurrence rates. The RFCA group had significantly higher peak oxygen consumption (VO 2max ), a better quality of life (Minnesota Living with Heart Failure Questionnaire score), and improved LVEF. However, RFCA for AF failed to reduce all-cause mortality in a specific meta-analysis of four RCTs that enrolled patients with LVEF ≤35%.

CONCLUSION

Compared with medical therapy, RFCA for AF in the setting of HF with impaired systolic function is associated with better clinical (HF hospitalization and all-cause mortality), structural (LVEF improvement), functional (VO 2max ), and quality of life outcomes. However, RFCA for AF failed to reduce all-cause mortality in RCTs that enrolled patients with LVEF ≤35% and thereby indicated the necessary stratification to identify patients who may benefit more from RFCA.

Atrial fibrillation in a pediatric patient caused by an unusual malignant etiology: A case report

This case report describes a 15-year-old patient with a known congenital malformation syndrome and immune deficiency, presenting with new-onset atrial fibrillation (AF) after a recent diagnosis of an intrathoracic mass. Transthoracic echocardiography showed a structurally and functionally normal heart and workup confirmed a primary diffuse large B-cell lymphoma, with pericardial and left atrial involvement on cardiac magnetic resonance imaging. Electrical cardioversion was successfully performed to convert the AF and chemotherapy was promptly started. Antiarrhythmic treatment was continued for 6 weeks, without recurrent AF. We discuss the pathogenesis of AF in the setting of malignancies as well as the management strategies of AF, mainly based on adult guidelines.

Ganglionic Plexus Ablation: A Step-by-step Guide for Electrophysiologists and Review of Modalities for Neuromodulation for the Management of Atrial Fibrillation

As the most common sustained arrhythmia, AF is a complex clinical entity which remains a difficult condition to durably treat in the majority of patients. Over the past few decades, the management of AF has focused mainly on pulmonary vein triggers for its initiation and perpetuation. It is well known that the autonomic nervous system (ANS) has a significant role in the milieu predisposing to the triggers, perpetuators and substrate for AF. Neuromodulation of ANS - ganglionated plexus ablation, vein of Marshall ethanol infusion, transcutaneous tragal stimulation, renal nerve denervation, stellate ganglion block and baroreceptor stimulation - constitute an emerging therapeutic approach for AF. The purpose of this review is to summarise and critically appraise the currently available evidence for neuromodulation modalities in AF.

Global patterns of prognostic biomarkers across disease space

There is a multitude of pathological conditions that affect human health, yet we currently lack a predictive model for most diseases, and underlying mechanisms that are shared by multiple diseases are poorly understood. We leveraged baseline clinical biomarker data and long-term disease outcomes in UK Biobank to build prognostic multivariate survival models for over 200 most common diseases. We construct a similarity map between biomarker-disease hazard ratios and demonstrate broad patterns of shared similarity in biomarker profiles across the entire disease space. Further aggregation of risk profiles through density based clustering showed that biomarker-risk profiles can be partitioned into few distinct clusters with characteristic patterns representative of broad disease categories. To confirm these risk patterns we built disease co-occurrence networks in the UK Biobank and US HCUP hospitalization databases, and compared similarity in biomarker risk profiles to disease co-occurrence. We show that proximity in the biomarker-disease space is strongly related to the occurrence of disease comorbidity, suggesting biomarker profile patterns can be used for both predicting future outcomes as well as a sensitive mechanism for detecting under-diagnosed disease states.

The impact of atrial fibrillation and atrial tachycardias on the hemodynamic status of patients with pulmonary hypertension

The impact of atrial fibrillation and atrial tachycardias (AF/AT), and their optimal treatment strategy in PH patients is still being discussed. The goal of this study was to evaluate the effect of AF/AT termination on the hemodynamic parameters in PH patients. We compared patients with pre-capillary pulmonary hypertension (PH group), left ventricular heart failure (LV-HF group), and a Control group. A repeated right heart catheterization was performed during the catheter ablation (CA) procedure. The first measurement was done in arrhythmia, the second after the sinus rhythm (SR) was restored. High frequency atrial stimulation was used to simulate AT in patients without arrhythmia presence at the time of the CA. The variation of pressure parameters in PH patients did not differ significantly from the Controls. There was a significant increase in the right ventricle pressure after the SR restoration in the LV-HF group compared to the Controls and PH group (+4 vs. -2 vs. -3 mmHg, p < 0.05). The cardiac index (CI) variation was not significant when compared between the study groups. An increase of the CI after the SR restoration was found in those patients with AF (+0.31 l/min/m² [IQR 0.18; 0.58]) in contrast to those patients with organized AT/high frequency atrial stimulation (-0.09 l/min/m², [IQR - 0.45; 0.19]). This difference was statistically significant (p < 0.05). The acute hemodynamic response to arrhythmia termination was not significantly different in the PH patients when compared to the Controls. In contrast to AT/high frequency stimulation, the restoration of SR in AF patients leads to an increased CI, irrespective of the presence or absence of PH.

His-bundle pacing vs biventricular pacing following atrioventricular nodal ablation in patients with atrial fibrillation and reduced ejection fraction: A multicenter, randomized, crossover study-The ALTERNATIVE-AF trial

BACKGROUND

Atrioventricular nodal ablation (AVNA) combined with biventricular pacing (BVP) improves outcomes in patients with persistent atrial fibrillation (AF), adequate rate control, and reduced left ventricular ejection fraction (LVEF). His-bundle pacing (HBP) delivers physiological ventricular activation and is a promising alternative to BVP.

OBJECTIVE

The purpose of this trial was to compare HBP with BVP following AVNA.

METHODS

In this multicenter, prospective, randomized crossover trial, we recruited patients with persistent AF and reduced LVEF (≤40%). All patients underwent AVNA and received both HBP and BVP. Patients were randomized to either HBP or BVP for 9 months (phase 1), then were switched to the alternative pacing modality for the next 9 months (phase 2). The primary endpoint was change in LVEF.

RESULTS

Fifty patients (age 64.3 ± 10.3 years; ventricular rate 93.1 ± 19.9 bpm; 72% male) were enrolled. Thirty-eight patients completed the 2 phases and were included in the crossover analysis. A significant improvement in LVEF was observed with HBP compared to BVP (phase 1: ΔLVEFHBP 21.3% and ΔLVEFBVP 16.7%; phase 2: ΔLVEFHBP 3.5% and ΔLVEFBVP -2.4%; Pgeneralizedadditivemodel = 0.015). Significant improvements in left ventricular end-diastolic diameter, New York Heart Association functional class, and B-type natriuretic peptide level were observed with both pacing modalities compared with baseline, whereas no significant differences were observed between HBP and BVP.

CONCLUSION

HBP delivers a modest but significant improvement in LVEF in patients with persistent AF, impaired ventricular function, and narrow QRS duration post-AVNA compared with BVP. Larger long-term trials are required to confirm the additional improvements in function with HBP.

Outcomes of catheter ablation versus antiarrhythmic therapy in patients with atrial fibrillation: a systematic review and meta-analysis

BACKGROUND

Recent data have shown an advantage of rhythm control over rate control for the treatment of atrial fibrillation (AF). Nevertheless, the data regarding efficacy of catheter ablation (CA) compared with antiarrhythmic drugs (AADs) in patients with AF is lacking. Therefore, we sought to evaluate recurrence of arrhythmia, all-cause mortality, cardiovascular deaths, stroke/TIA, and all-cause readmissions of CA compared with AAD in patients with AF.

METHODS

Systematically searched through PubMed, Google Scholar, EMBASE, and Cochrane for randomized control trials that compared CA and AAD in atrial fibrillation patients. Review Manager 5.4 and OpenMetaAnalyst were used to analyze the data. Data was pooled for the outcomes using random-effect models (DerSimonian and Laird) and reported as pooled odds ratio (OR).

RESULTS

A total of 4822 patients were included. The CA group had 2417 patients while the AAD group included 2405 patients. Pooled data demonstrated that the CA arm had a statistically significant decrease in risk for recurrence of arrhythmia as compared to AAD (OR 0.25; [95% CI, 0.18-0.36]; p < 0.001). All-cause readmission was statistically significantly lower in CA as compared to AAD (OR 0.33; [95%CI, 0.17-0.63]; p < 0.001). For other secondary outcomes, there was no statistically significant difference between CA and AAD with regard to all-cause mortality (OR 0.75; [95% CI, 0.55-1.03]), cardiovascular death (OR 0.76; [95% CI, 0.22-2.54]), bleeding (OR 1.09, [95% CI 0.74, 1.61]), or stroke/TIA outcome (OR 0.90, [95% CI, 0.59-1.37]).

CONCLUSIONS

In this study of pooled data from 16 RCTs, CA utilization for atrial fibrillation had improved freedom from arrhythmia as well as reduced all-cause readmission compared with AAD.

Rate or Rhythm Control in CRT (RHYTHMIC): Study rationale and protocol

Background

Atrial fibrillation (AF) has several detrimental effects on heart failure patients treated with cardiac resynchronization therapy (CRT). These include suboptimal biventricular pacing and the loss of atrioventricular (AV) synchrony. AV node ablation improves biventricular pacing and clinical outcomes in large observational studies. However, restoration of sinus rhythm with AF ablation may have additional benefits.

Objectives

To compare the effects of AV node ablation and AF ablation on echocardiographic and symptomatic outcomes in patients with CRT and suboptimal biventricular pacing.

Methods

RHYTHMIC is a multicenter prospective randomized controlled trial. Seventy patients will be recruited and randomized to each ablation strategy in a 1:1 ratio. Key inclusion criteria include a previous CRT implant (with atrial lead) for dyssynchronous heart failure, and biventricular pacing <95% secondary to AF. Patients with permanent AF will be excluded.

Results

Patients will undergo baseline assessment including transthoracic echocardiography (TTE), device check, blood tests, electrocardiogram (ECG), 6-minute walk test, and symptom questionnaire. They will then undergo either AV node ablation or AF ablation according to their allocated group. Follow-up will occur at 1 week (TTE and ECG) and at 6 months (repeat of baseline investigations). The primary endpoint will be change in left ventricular ejection fraction on TTE.

Conclusion

This is the first randomized controlled trial comparing AV node ablation and AF ablation in patients with CRT. We anticipate it will provide valuable insight into the management of this frequently encountered clinical scenario in a challenging patient cohort.

Atrial Fibrillation and Transvenous Lead Extraction-A Comprehensive Subgroup Analysis of the GermAn Laser Lead Extraction RegistrY (GALLERY)

Background: Atrial fibrillation is the most common arrhythmia and has been described as driver of cardiovascular morbidity and risk factor for cardiac device-related complications, as well as in transvenous lead extraction (TLE). Objectives: Aim of this study was to characterize the procedural outcome and risk-factors of patients with atrial fibrillation (AF) undergoing TLE. Methods: We performed a subgroup analysis of all AF patients in the GALLERY (GermAn Laser Lead Extraction RegistrY) database. Predictors for all-cause mortality were assessed. Results: A total number of 510 patients with AF were identified with a mean age of 74.0 ± 10.3 years. Systemic infection (38.4%) was the leading cause for TLE, followed by local infection (37.5%) and lead dysfunction (20.4%). Most of the patients (45.9%) presented with pacemaker systems to be extracted. The total number of leads was 1181 with a 2.3 ± 0.96 leads/patient. Clinical procedural success was achieved in 97.1%. Occurrence of major complications was 1.8% with a procedure-related mortality of 1.0%. All-cause mortality was high with 5.9% and septic shock being the most common cause. Systemic device infection (OR: 49.73; 95% CI: 6.56−377.09, p < 0.001), chronic kidney disease (CKD; OR: 2.67; 95% CI: 1.01−7.03, p = 0.048) and a body mass index < 21 kg/m2 (OR: 6.6; 95% CI: 1.68−25.87, p = 0.007) were identified as independent predictors for all-cause mortality. Conclusions: TLE in AF patients is effective and safe, but in patients with systemic infection the mortality due to septic shock is high. Systemic infection, CKD and body mass index <21 kg/m2 are risk factors for death in patient with AF undergoing TLE.

Atrial Fibrillation Burden Specifically Determines Human Ventricular Cellular Remodeling

BACKGROUND

Atrial fibrillation (AF) can either be a consequence or an underlying mechanism of left ventricular systolic dysfunction. Patients included in the CASTLE-AF (Catheter Ablation vs. Standard Conventional Treatment in Patients With LV Dysfunction and AF) trial who suffered from AF and left ventricular systolic dysfunction benefited from an AF burden <50% after catheter ablation compared with those patients with an AF burden >50%.

OBJECTIVES

This analysis tried to explain the clinical findings of the CASTLE-AF trial regarding AF burden in a "back-to-bench" approach.

METHODS

To study the ventricular effects of different AF burdens, experiments were performed using human ventricular induced pluripotent stem cell-derived cardiomyocytes undergoing in vitro AF simulation. Epifluorescence microscopy, action potential measurements, and measurements of sarcomere regularity were conducted.

RESULTS

Induced pluripotent stem cell-derived cardiomyocytes stimulated with AF burden of 60% or higher displayed typical hallmarks of heart failure. Ca²⁺ transient amplitude was significantly reduced indicating negative inotropic effects. Action potential duration was significantly prolonged, which represents a potential trigger for arrhythmias. A significant decrease of sarcomere regularity could explain impaired cardiac contractility in patients with high AF burden. These effects were more pronounced after 7 days of AF simulation compared with 48 hours.

CONCLUSIONS

Significant functional and structural alterations occurred at the cellular level at a threshold of ∼50% AF burden as it was observed to be harmful in the CASTLE-AF trial. Therefore, these translational results may help to understand the findings of the CASTLE-AF trial.

The impact of myocardial fibrosis biomarkers in a heart failure population with atrial fibrillation—The HARVEST-Malmö study

Background

Several studies suggest that circulating biomarkers of myocardial fibrosis are associated with worse prognosis in subjects with atrial fibrillation (AF). Here, we aimed to explore associations between fibrosis biomarkers, prevalent AF, and left atrial volume (LAV) enlargement in subjects with heart failure (HF). Additionally, we evaluated the prognostic impact of fibrotic biomarkers in HF with co-existing AF.

Materials and methods

Patients hospitalized for HF (n = 316, mean age 75 years; 30% women) were screened for AF. Seven proteins previously associated with myocardial fibrosis [metalloproteinase inhibitor 4 (TIMP-4), suppression of tumorigenicity 2 (ST-2), galectin-3 (GAL-3), growth/differentiation factor-15 (GDF-15), and matrix metalloproteinase 2, 3, and 9 (MMP-3, MMP-3, and MMP-9, respectively)] were analyzed using a proximity extension assay. Proteins with significant Bonferroni-corrected associations with mortality and re-hospitalization risk were taken forward to multivariable Cox regression analyses. Further, Bonferroni-corrected multivariable logistic regression models were used to study associations between protein plasma levels, prevalent AF, and severely enlarged left atrial volume index (LAVI ≥ 48 ml/m²).

Results

Prevalent AF was observed in 194 patients at the hospitalization of whom 178 (92%) were re-hospitalized and 111 (57%) died during the follow-up period. In multivariable logistic regression models, increased plasma levels of TIMP-4, GDF-15, and ST-2 were associated with the prevalence of AF, whereas none of the seven proteins showed any significant association with severely enlarged LAVI. Increased plasma levels of five proteins yielded significant associations with all-cause mortality in patients with co-existing AF; TIMP-4 (HR 1.33; CI95% 1.07–1.66; p = 0.010), GDF-15 (HR 1.30; CI95% 1.05–1.62; p = 0.017), GAL-3 (HR 1.29; CI95% 1.03–1.61; p = 0.029), ST-2 (HR 1.48; CI95% 1.18–1.85; p < 0.001), and MMP-3 (HR 1.33; CI95% 1.09–1.63; p = 0.006). None of the proteins showed any significant association with re-hospitalization risk.

Conclusion

In this study, we were able to demonstrate that elevated levels of three plasma proteins previously linked to myocardial fibrosis are associated with prevalent AF in a HF population. Additionally, higher levels of five plasma proteins yielded an increased risk of mortality in the HF population with or without co-existing AF.

Catheter Ablation versus Medical Therapy of Atrial Fibrillation in Patients with Heart Failure: An Updated Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background: Atrial fibrillation (AF) and heart failure (HF) often coexist and synergistically contribute to an increased risk of hospitalization, stroke, and mortality. Objective: To compare the efficacy of catheter ablation (CA) versus medical therapy (MT) in HF patients with AF. Methods: Electronic databases were queried for randomized controlled trials (RCTs) of CA versus MT of AF in patients with HF. Risk ratios (RRs), mean differences (MDs), and 95% confidence intervals (CIs) were measured using the Mantel−Haenszel method. Results: A total of nine RCTs enrolling 2155 patients met the inclusion criteria. Compared to MT, CA led to a significant reduction in the composite of all-cause mortality and HF hospitalization (24.6% vs. 37.1%; RR: 0.65 (95% CI: 0.53−0.80); p < 0.0001), all-cause mortality (8.8% vs. 13.6%; RR: 0.65 (95% CI: 0.51−0.82); p = 0.0005), HF hospitalization (15.4% vs. 22.4%; (RR: 0.67 (95% CI: 0.54−0.82); p = 0.0001), AF recurrence (31.8% vs. 77.0%; RR: 0.36 (95% CI: 0.24−0.54); p < 0.0001), and cardiovascular (CV) death (4.9% vs. 8.4%; RR: 0.58 (95% CI: 0.39−0.86); p = 0.007). CA improved the left ventricular ejection fraction (MD:4.76% (95% CI: 2.35−7.18); p = 0.0001), 6 min walk test (MD: 20.48 m (95% CI: 10.83−30.14); p < 0.0001), peak oxygen consumption (MD: 3.1 2mL/kg/min (95% CI: 1.01−5.22); p = 0.004), Minnesota Living with Heart Failure Questionnaire score (MD: −6.98 (95% CI: −12−03, −1.93); p = 0.007), and brain natriuretic peptide levels (MD:−133.94 pg/mL (95% CI: −197.33, −70.55); p < 0.0001). Conclusions: In HF patients, AF catheter ablation was superior to MT in reducing CV and all-cause mortality. Further significant benefits occurred within the ablation group in terms of HF hospitalizations, AF recurrences, the systolic function, exercise capacity, and quality of life.

Left ventricular systolic function affects right atrial pressure as prognosticator in patients with heart failure

The effect of the left ventricular ejection fraction (LVEF) on the prognostic impact of the right atrial pressure (RAP) in patients with heart failure (HF) requires clarification. We aimed to investigate whether LVEF affects the prognostic impact of RAP estimated from inferior vena cava (IVC) measurements in patients hospitalized with HF. Initially, this observational study included 1349 consecutive patients urgently hospitalized with HF. After patient exclusions, 506 and 484 patients with reduced (< 40%) and with non-reduced (≥ 40%) LVEF, respectively, were assigned according to maximum IVC diameter and its collapsibility, to the Normal-RAP (diameter ≤ 2.1 cm; collapsibility ≥ 50%), High-RAP (diameter > 2.1 cm; collapsibility < 50%), and Intermediate-RAP (others) groups. The endpoint comprised cardiovascular death after discharge and hospitalization for HF recurrence. During the observation period, 247 (49%) patients with LVEF < 40% and 178 (37%) patients with LVEF ≥ 40% experienced the endpoint. The patient subgroups with LVEF < 40% had comparable event rates (ptrend = 0.10). The High-RAP subgroup with LVEF ≥40% had a higher event rate than the other subgroups (p < 0.001). The RAP independently predicted the endpoint in patients with LVEF ≥ 40% (hazard ratio: 1.26; 95% confidence interval: 1.01-1.59). The interaction between the RAP groups and LVEF regarding the primary endpoint was significant (pinteraction = 0.007). Stratifying patients with HF according to IVC measurements may predict the post-discharge cardiovascular prognoses of patients with non-reduced LVEF, but not that of patients with reduced LVEF.

Preventing preventable strokes: A study protocol to push guideline-driven atrial fibrillation patient education via patient portal

Background

The main approach to preventing stroke in patients with atrial fibrillation (AF) is anticoagulation (AC), but only about 60% of at-risk individuals are on AC. Patient-facing electronic health record–based interventions have produced mixed results. Little is known about the impact of health portal–based messaging on AC use.

Objective

The purpose of this study was describe a protocol we will use to measure the association between AC use and patient portal message opening. We also will measure patient attitudes toward education materials housed on a professional society Web site.

Methods

We will send portal messages to patients aged ≥18 years with AF 1 week before an office/teleconference visit with a primary care or cardiology provider. The message will be customized for 3 groups of patients: those on AC; those at elevated risk but off AC; and those not currently at risk but may be at risk in the future. Within the message, we will embed a link to UpBeat.org, a Web site of the Heart Rhythm Society containing patient educational materials. We also will embed a link to a survey. Among other things, the survey will request patients to rate their attitude toward the Heart Rhythm Society Web pages. To measure the effectiveness of the intervention, we will track AC use and its association with message opening, adjusting for potential confounders.

Conclusion

If we detect an increase in AC use correlates with message opening, we will be well positioned to conduct a future comparative effectiveness trial. If patients rate the UpBeat.org materials highly, patients from other institutions also may benefit from receiving these materials.

Cardiac Remodelling Following Cancer Therapy: A Review

Cardiac remodelling is characterized by abnormal changes in the function and morphological properties such as diameter, mass, normal diameter of cavities, heart shape, fibrosis, thickening of vessels and heart layers, cardiomyopathy, infiltration of inflammatory cells, and some others. These damages are associated with damage to systolic and diastolic abnormalities, damage to ventricular function, and vascular remodelling, which may lead to heart failure and death. Exposure of the heart to radiation or anti-cancer drugs including chemotherapy drugs such as doxorubicin, receptor tyrosine kinase inhibitors (RTKIs) such as imatinib, and immune checkpoint inhibitors (ICIs) can induce several abnormal changes in the heart structure and function through the induction of inflammation and fibrosis, vascular remodelling, hypertrophy, and some others. This review aims to explain the basic mechanisms behind cardiac remodelling following cancer therapy by different anti-cancer modalities.

The Atrium in Atrial Fibrillation - A Clinical Review on How to Manage Atrial Fibrotic Substrates

Atrial fibrillation (AF) is the most common sustained arrhythmia in the population and is associated with a significant clinical and economic burden. Rigorous assessment of the presence and degree of an atrial arrhythmic substrate is essential for determining treatment options, predicting long-term success after catheter ablation, and as a substrate critical in the pathophysiology of atrial thrombogenesis. Catheter ablation of AF has developed into an essential rhythm-control strategy. Nowadays is one of the most common cardiac ablation procedures performed worldwide, with its success inversely related to the extent of atrial structural disease. Although atrial substrate evaluation remains complex, several diagnostic resources allow for a more comprehensive assessment and quantification of the extent of left atrial structural remodeling and the presence of atrial fibrosis. In this review, we summarize the current knowledge on the pathophysiology, etiology, and electrophysiological aspects of atrial substrates promoting the development of AF. We also describe the risk factors for its development and how to diagnose its presence using imaging, electrocardiograms, and electroanatomic voltage mapping. Finally, we discuss recent data regarding fibrosis biomarkers that could help diagnose atrial fibrotic substrates.

Variation in heart rate range by 24-h Holter monitoring predicts heart failure in patients with atrial fibrillation

AIMS

The analysis of heart rate (HR) changes, such as the HR variability or HR turbulence, has been reported as a marker of cardiovascular events during sinus rhythm; however, those relationships during atrial fibrillation (AF) remain controversial, and those parameters are not commonly used in AF patients. We sought to investigate the relationship between a simple index focused on the HR and heart failure (HF) events in patients with permanent AF.

METHODS AND RESULTS

We enrolled 198 patients with permanent AF and evaluated the HR range, defined as the maximum HR minus the minimum HR on 24-h Holter electrocardiogram recordings. The patients were divided into two groups, i.e., the larger (n = 101) and smaller (n = 97) HR range (HRR) groups, determined by the median value. The HF events were defined as hospitalizations for HF or urgent hospital visits due to exacerbations of one's HF status. The observation period of this study was set at 5 years from registration. The median age was 73 (68-77) years, and 29% were female. The median HRR was 84 (63-118) beats per minutes (bpm). During the observational period of 1825 days (median), HF events occurred in 37 (0.047 per patient-year) patients. In a log-rank test, the larger HRR group had more frequent HF events than the smaller HRR group (P = 0.0078). In the adjusted Cox proportional hazards model using the significantly different factors from the univariate analysis (Model 1) and factors and medications associated with HF (Model 2), the larger HRR group had a higher prevalence of HF events than the smaller HRR group for both models [Model 1, adjusted hazard ratio = 3.21, 95% confidence interval (CI) 1.593-6.708, P = 0.0009; Model 2, adjusted hazard ratio = 3.12, 95% CI 1.522-6.685, P = 0.002]. When analysed using the time-dependent Cox proportional hazards model, the HRR was associated with HF with a statistically significant difference in both the univariate and multivariate analyses [hazard ratio = 1.01, 95% CI 1.006-1.020, P = 0.0002; Model 1, adjusted hazard ratio = 1.02, 95% CI 1.011-1.027, P < 0.0001; Model 2, adjusted hazard ratio = 1.01, 95% CI 1.008-1.021, P = 0.0003). There was no significant difference in the chronotropic medications between the two groups.

CONCLUSIONS

In patients with permanent AF, a larger HRR was associated with HF events.

Impact of left atrial low-voltage areas during initial ablation procedures on very late recurrence of atrial fibrillation

BACKGROUND

Very late recurrence of atrial fibrillation (VLRAF) occurring >1 year after catheter ablation may influence long-term follow-up strategies, including oral anticoagulant therapy. However, little is known about the predictors of this condition. Given that the prevalence of left atrial low-voltage areas (LVAs) is strongly associated with the recurrence of atrial tachyarrhythmias following catheter ablation, we hypothesized that VLRAF might occur more frequently in patients with LVAs at the time of initial ablation. The purpose of this study was to investigate the impact of LVAs on VLRAF.

METHODS

This study included 1001 consecutive patients undergoing initial ablation procedures for AF. LVAs were defined as regions with bipolar peak-to-peak voltages of <0.50 mV on the voltage map obtained during sinus rhythm after pulmonary vein isolation. During a 1-year follow-up period, 248 patients had a late recurrence of AF (LRAF), defined as recurrence within 3 to 12 months after ablation. The occurrence of VLRAF was examined in 711 patients without LRAF who were followed for more than 1 year.

RESULTS

A total of 711 patients who did not develop AF recurrence within 1 year and for whom clinical data were available after 1 year were analyzed. During a median follow-up of 25 (19, 37) months, VLRAF more than one year after the initial ablation was detected in 123 patients. On multivariate analysis, independent predictors of VLRAF were the existence of LVAs, female, left atrial diameter and early recurrence of AF. A Kaplan-Meier analysis showed that the AF-free survival rate was significantly lower in patients with LVAs than in those without LVAs within 1 year and on more than 1 year follow-up. (P<0.001) An additional Kaplan-Meier analysis of the incidence of VLRAF in propensity score-matched patients with and without LVAs showed that VLRAF occurred significantly more frequently in patients with LVAs. (P=0.003) CONCLUSIONS: LVAs during the initial AF ablation procedures have an impact on VLRAF occurrence. This article is protected by copyright. All rights reserved.