Atrial fibrillation

Exploring Atrial Fibrillation: Understanding the Complex Relation Between Lifestyle and Genetic Factors

Cardiovascular diseases (CVDs) are the leading cause of death worldwide across diverse ethnic groups. Among these, atrial fibrillation (AF) stands as one of the most prevalent types of arrhythmias and the primary cause of stroke. Risk factors associated with AF include alcohol consumption, aging, high blood pressure, hypertension, inflammation, and genetic factors. A family history of CVD could indicate an increased risk. Consequently, genetic, and genomic testing should be performed to identify the molecular etiology of CVDs and assess at-risk patients. It is important to note that CVDs are the results of the complex interplay of genes and environmental factors, including ethnicity. In this case, the proband's clinic story includes a history of smoking abuse for 10 years (10 cigarettes per day), obesity, hypertension, and an associated familial history. These risk factors, along with genetic variants, could trigger the early onset of AF. In recent years, genetic and genomic studies have significantly advanced our understanding of CVD etiology, given that next-generation sequencing (NGS) allows for the identification of genetic variants that could contribute to these pathologies. Furthermore, NGS facilitates early diagnosis, personalized pharmacological approaches, and identification of novel biomarkers. Thus, NGS is a valuable tool in CVD management. However, such studies are limited in Ecuador, a low- and middle-income country. Several challenges contribute to this gap, encompassing economic, infrastructural, and educational obstacles. Notably, the cost of genetic and genomic studies may also pose a barrier, restricting access to a portion of the population. In this case report, we present a 56-year-old Ecuadorian woman, who has been diagnosed with AF; however, after performing NGS no disease-associated variants were found, despite having strong clinical signs and symptoms. In summary, this case report contributes valuable insights into the complex interplay between genetic and lifestyle factors in the development and management of AF. The case report aims to underscore the potential impact of genetic variants on disease risk, even when classified as variants of uncertain significance, and the importance of an integral approach to patient care that includes genetic screening, lifestyle interventions, and tailored pharmacological treatment.

An Integrated Optogenetic and Bioelectronic Platform for Regulating Cardiomyocyte Function

Bioelectronic medicine is emerging as a powerful approach for restoring lost endogenous functions and addressing life-altering maladies such as cardiac disorders. Systems that incorporate both modulation of cellular function and recording capabilities can enhance the utility of these approaches and their customization to the needs of each patient. Here is report an integrated optogenetic and bioelectronic platform for stable and long-term stimulation and monitoring of cardiomyocyte function in vitro. Optical inputs are achieved through the expression of a photoactivatable adenylyl cyclase, that when irradiated with blue light causes a dose-dependent and time-limited increase in the secondary messenger cyclic adenosine monophosphate with subsequent rise in autonomous cardiomyocyte beating rate. Bioelectronic readouts are obtained through a multi-electrode array that measures real-time electrophysiological responses at 32 spatially-distinct locations. Irradiation at 27 µW mm-2 results in a 14% elevation of the beating rate within 20-25 min, which remains stable for at least 2 h. The beating rate can be cycled through "on" and "off" light states, and its magnitude is a monotonic function of irradiation intensity. The integrated platform can be extended to stretchable and flexible substrates, and can open new avenues in bioelectronic medicine, including closed-loop systems for cardiac regulation and intervention, for example, in the context of arrythmias.

Simulating left atrial arrhythmias with an interactive N-body model

BACKGROUND

Heart disease and strokes are leading global killers. While atrial arrhythmias are not deadly by themselves, they can disrupt blood flow in the heart, causing blood clots. These clots can travel to the brain, causing strokes, or to the coronary arteries, causing heart attacks. Additionally, prolonged periods of elevated heart rates can lead to structural and functional changes in the heart, ultimately leading to heart failure if untreated. The left atrium, with its more complex topology, is the primary site for complex arrhythmias. Much remains unknown about the causes of these arrhythmias, and computer modeling is employed to study them.

METHODS

We use N-body modeling techniques and parallel computing to build an interactive model of the left atrium. Through user input, individual muscle attributes can be adjusted, and ectopic events can be placed to induce arrhythmias in the model. Users can test ablation scenarios to determine the most effective way to eliminate these arrhythmias.

RESULTS

We set up muscle conditions that either spontaneously generate common arrhythmias or, with a properly timed and located ectopic event, induce an arrhythmia. These arrhythmias were successfully eliminated with simulated ablation.

CONCLUSIONS

We believe the model could be useful to doctors, researchers, and medical students studying left atrial arrhythmias.

Independent effects of the glucose-to-glycated hemoglobin ratio on mortality in critically ill patients with atrial fibrillation

BACKGROUND

The glucose-to-glycated hemoglobin ratio (GAR) represents stress hyperglycemia, which has been closely associated with adverse outcomes in cardio-cerebrovascular diseases. No studies have examined the association between stress hyperglycemia and atrial fibrillation (AF) in critically ill patients. This study aims to explore the relationship between GAR and the prognosis of critically ill patients with AF.

METHODS

A retrospective cohort of patients was selected from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. The GAR was calculated based on fasting blood glucose and glycated hemoglobin levels measured after admission. The primary outcome was the 30-day mortality rate, with secondary outcomes being the 90-day and 365-day mortality rates. The GAR was divided into tertiles, and Kaplan-Meier analysis was employed to compare differences in mortality rates between groups. The Cox proportional hazards model and restricted cubic splines (RCS) were utilized to evaluate the relationship between the GAR and mortality. Subsequently, a segmented regression model was constructed to analyze threshold effects in cases where nonlinear relationships were determined.

RESULTS

In this cohort, the second tertile of the GAR exhibited lower mortality rates at 30 days (10.56% vs 6.33% vs 14.51%), 90 days (17.11% vs 10.09% vs 17.88%), and 365 days (25.30% vs 16.15% vs 22.72%). In the third tertile, the risk of mortality at 30 days increased by 165% (HR = 2.65, 95% CI 1.99-3.54, p < 0.001), at 90 days increased by 113% (HR = 2.13, 95% CI 1.68-2.70, p < 0.001), and at 365 days increased by 70% (HR = 1.70, 95% CI 1.68-2.70, p < 0.001). The association between the GAR and patient mortality demonstrated a "J-shaped" non-linear correlation. Once the GAR exceeded 15.915, each incremental unit increase in the ratio was associated with a 27.2% increase in the risk of 30-day mortality in critically ill atrial fibrillation patients (HR = 1.262, 95% CI 1.214-1.333, p < 0.001).

CONCLUSION

The GAR is associated with both short-term and long-term mortality in critically ill patients with AF in a J-shaped relationship. Both low and excessively high GAR values indicate poor prognosis.

Atrial Fibrillation and Older Age Predict Serum Brain-Derived Neurotrophic Factor Levels Among Patients With Heart Failure

BACKGROUND

Predictors have not been determined of serum brain-derived neurotrophic factor (BDNF) levels among patients with heart failure (HF).

OBJECTIVE

The primary purpose was to evaluate history of atrial fibrillation, age, gender, and left ventricular ejection fraction as predictors of serum BDNF levels at baseline, 10 weeks, and 4 and 8 months after baseline among patients with HF.

METHODS

This study was a retrospective cohort analyses of 241 patients with HF. Data were retrieved from the patients' health records (coded history of atrial fibrillation, left ventricular ejection fraction), self-report (age, gender), and serum BDNF. Linear multiple regression analyses were conducted.

RESULTS

One hundred three patients (42.7%) had a history of atrial fibrillation. History of atrial fibrillation was a significant predictor of serum BDNF levels at baseline (β = -0.16, P = .016), 4 months (β = -0.21, P = .005), and 8 months (β = -0.19, P = .015). Older age was a significant predictor at 10 weeks (β = -0.17, P = .017) and 4 months (β = -0.15, P = .046).

CONCLUSIONS

Prospective studies are needed to validate these results. Clinicians need to assess patients with HF for atrial fibrillation and include treatment of it in management plans.

Spexin Diminishes Atrial Fibrillation Vulnerability by Acting on Galanin Receptor 2

BACKGROUND

G protein-coupled receptors play a critical role in atrial fibrillation (AF). Spexin is a novel ligand of galanin receptors (GALRs). In this study, we investigated the regulation of spexin and GALRs on AF and the underlying mechanisms.

METHODS

Global spexin knockout (SPX-KO) and cardiomyocyte-specific GALRs knockout (GALR-cKO) mice underwent burst pacing electrical stimulation. Optical mapping was used to determine atrial conduction velocity and action potential duration. Atrial myocyte action potential duration and inward rectifying K+ current (IK1) were recorded using whole-cell patch clamps. Isolated cardiomyocytes were stained with Fluo-3/AM dye, and intracellular Ca2+ handling was examined by CCD camera. A mouse model of AF was established by Ang-II (angiotensin II) infusion.

RESULTS

Spexin plasma levels in patients with AF were lower than those in subjects without AF, and knockout of spexin increased AF susceptibility in mice. In the atrium of SPX-KO mice, potassium inwardly rectifying channel subfamily J member 2 (KCNJ2) and sarcolipin (SLN) were upregulated; meanwhile, IK1 current was increased and Ca2+ handling was impaired in isolated atrial myocytes of SPX-KO mice. GALR2-cKO mice, but not GALR1-cKO and GALR3-cKO mice, had a higher incidence of AF, which was associated with higher IK1 current and intracellular Ca2+ overload. The phosphorylation level of CREB (cyclic AMP responsive element binding protein 1) was upregulated in atrial tissues of SPX-KO and GALR2-cKO mice. Chromatin immunoprecipitation confirmed the recruitment of p-CREB to the proximal promoter regions of KCNJ2 and SLN. Finally, spexin treatment suppressed CREB signaling, decreased IK1 current and decreased intracellular Ca2+ overload, which thus reduced the inducibility of AF in Ang-II-infused mice.

CONCLUSIONS

Spexin reduces atrial fibrillation susceptibility by inhibiting CREB phosphorylation and thus downregulating KCNJ2 and SLN transcription by GALR2 receptor. The spexin/GALR2/CREB signaling pathway represents a novel therapeutic avenue in the development of agents against atrial fibrillation.

Development of a Nomogram That Predicts the Risk of Atrial Fibrillation in Patients with Coronary Heart Disease

Objective

To explore the risk factors of atrial fibrillation (AF) in patients with coronary heart disease (CHD), and to construct a risk prediction model.

Methods

The participants in this case-control study were from the cardiovascular Department of Changzhou Affiliated Hospital of Nanjing University of Chinese Medicine from June 2016 to June 2023, and they were divided into AF group and non-AF group according to whether AF occurred during hospitalization. The clinical data of the two groups were compared by retrospective analysis. Multivariate Logistic regression analysis was used to investigate the risk factors of AF occurrence in CHD patients. The nomogram model was constructed with R 4.2.6 language "rms" package, and the model's differentiation, calibration and effectiveness were evaluated by drawing ROC curve, calibration curve and decision curve.

Results

A total of 1258 patients with CHD were included, and they were divided into AF group (n=92) and non-AF group (n=1166) according to whether AF was complicated. Logistic regression analysis showed that age, coronary multiple branch lesion, history of heart failure, history of drinking, pulmonary hypertension, left atrial diameter, left ventricular end-diastolic diameter and diabetes mellitus were independent risk factors for the occurrence of AF in CHD patients (P < 0.05). The ROC curve showed that the AUC of this model was 0.956 (95% CI (0.916, 0.995)) and the consistency index was 0.966. The calibration curve of the model is close to the ideal curve. The analysis of decision curve shows that the prediction value of the model is better when the probability threshold of the model is 0.042~0.963.

Conclusion

The nomogram model established in this study for predicting the risk of AF in patients with CHD has better predictive performance and has certain reference value for clinical identification of high-risk groups prone to AF in patients with CHD.

Pre-Existing Atrial Fibrillation in Hospitalized Patients with COVID-19: Insights from the CARDIO COVID 19-20 Registry

Pre-existing (chronic) atrial fibrillation (AF) has been identified as a risk factor for cardiovascular complications and mortality in patients with COVID-19; however, evidence in Latin America (LATAM) is scarce. This prospective and multicenter study from the CARDIO COVID 19-20 database includes hospitalized adults with COVID-19 from 14 countries in LATAM. A parsimonious logistic regression model was used to identify the main factors associated with mortality in a simulated case-control setting comparing patients with a history of AF to those without. In total, 3260 patients were included, of which 115 had AF. The AF group was older, had a higher prevalence of comorbidities, and had greater use of cardiovascular medications. In the model, AF, chronic kidney disease, and a respiratory rate > 25 at admission were associated with higher in-hospital mortality. The use of corticosteroids did not reach statistical significance; however, an effect was seen through the confidence interval. Thus, pre-existing AF increases mortality risk irrespective of other concomitant factors. Chronic kidney disease and a high respiratory rate at admission are also key factors for in-hospital mortality. These findings highlight the importance of comorbidities and regional characteristics in COVID-19 outcomes, in this instance, enhancing the evidence for patients from LATAM.

Bibliometric analysis of atrial fibrillation and ion channels

Atrial fibrillation (AF) is a common clinical malignant arrhythmia with an increasing global incidence. Ion channel dysfunction is an important mechanism in the development of AF. In this study, we used bibliometrics to analyze the studies of ion channels and AF, aiming to provide inspiration and reference for researchers. A total of 3179 literature citations were obtained from Web of Science core databases. Analysis software included Excel 2019, VOSviewer 1.6.16, and CiteSpace 5.7.R2. This field of research has been growing since 1985. The most active country is the United States. The University of Montreal is the most important research institution. The journal Cardiovascular Research has published the largest number of articles in this field. Stanley Nattel and Dobromir Dobrev are the most frequently cited authors. The most cited literature was published in Nature and Science. Cardiac electrophysiology, gene expression, pathogenesis of AF, and AF prevention and treatment are the hot topics for this field research. Cardiac fibrillation and catheter ablation may be future research hotspots in this field.

Rhythm vs Rate Control Strategy for Atrial Fibrillation: A Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Rhythm control, either with antiarrhythmic drugs or catheter ablation, and rate control strategies are the cornerstones of atrial fibrillation (AF) management. Despite the increasing role of rhythm control over the past few years, it remains inconclusive which strategy is superior in improving clinical outcomes.

OBJECTIVES

This study summarizes the total and time-varying evidence regarding the efficacy of rhythm- vs rate-control strategies in the management of AF.

METHODS

We systematically perused the MEDLINE, CENTRAL (Cochrane Central Register of Controlled Trials), and Web of Science databases for randomized controlled trials from inception to November 2023. We included studies that compared the efficacy of rhythm control (ie, antiarrhythmic drugs classes Ia, Ic, or III, AF catheter ablation, and electrical cardioversion) and rate control (ie, beta-blocker, digitalis, or calcium antagonist) strategies among patients with nonvalvular AF. The primary outcome was cardiovascular (CV) death, whereas secondary outcomes included all-cause death, stroke, hospitalization for heart failure (HF), sinus rhythm at the end of the follow-up, and rhythm control-related adverse events. A cumulative meta-analysis to assess temporal trends and a meta-regression analysis using the percentage of ablation use was performed.

RESULTS

We identified 18 studies with a total of 17,536 patients (mean age: 68.6 ± 9.7 years, 37.9% females) and a mean follow-up of 28.5 months. Of those, 31.9% had paroxysmal AF. A rhythm control strategy reduced CV death (HR: 0.78; 95% CI: 0.62-0.96), stroke (HR: 0.801; 95% CI: 0.643-0.998), and hospitalization for HF (HR: 0.80; 95% CI: 0.69-0.94) but not all-cause death (HR: 0.86; 95% CI: 0.73-1.02) compared with a rate control strategy. This benefit was driven by contemporary studies, whereas more ablation use within the rhythm control arm was associated with improved outcomes, except stroke.

CONCLUSIONS

In patients with AF, a contemporary rhythm control strategy leads to reduced CV mortality, HF events, and stroke compared with a rate control strategy.

Correlation between left atrial appendage morphology based on fractal dimension quantification and its hemodynamic parameters in patients with atrial fibrillation

AIMS

To investigate the relationship between left atrial appendage (LAA) morphology, quantified based on fractal dimension (FD), and LAA hemodynamic parameters in patients with atrial fibrillation (AF), in an effort to reveal the effect of LAA shape on blood flow.

MATERIALS AND METHODS

225 patients with AF who underwent cardiac computed tomography angiography (CTA) and transesophageal echocardiography (TEE) were enrolled. LAA morphology was quantified based on FD on cardiac CTA images, and LAA hemodynamic parameters, including injection fraction (EF), filling peak flow velocity (FV), maximum speed of emptying (PEV), and wall motion velocity (WMV), were assessed using TEE.

RESULTS

We divided the patients with AF into two groups based on a mean LAA FD of 1.32: the low FD group (n=124) and the high FD group (n=101). Compared to the low FD group, there were more patients with LAA circulatory stasis/thrombus (P=0.008) in the high FD group, as well as lower LAA FV (P=0.004), LAA PEV (P=0.007), and LAA WMV (P=0.007). LAA FD was an independent and significant determinant of LAA EF (β = -11.755, P=0.001), LAA FV (β = -17.364, P=0.004), LAA PEV (β = -18.743, P<0.001), and LAA WMV (β = -7.740, P=0.001) in multiple linear regression analysis.

CONCLUSIONS

LAA FD is an essential determinant of LAA hemodynamic parameters, suggesting that the relatively complex morphology of the LAA may influence its hemodynamics, which can correlate with embolic events.

Ventriculoperitoneal Shunt Placement Safety in Idiopathic Normal Pressure Hydrocephalus: Anticoagulated Versus Non-Anticoagulated Patients

BACKGROUND

Many patients with idiopathic normal pressure hydrocephalus (iNPH) have medical comorbidities requiring anticoagulation that could negatively impact outcomes. This study evaluated the safety of ventriculoperitoneal shunt placement in iNPH patients on systemic anticoagulation versus those not on anticoagulation.

METHODS

Patients >60 years of age with iNPH who underwent shunting between 2018 and 2022 were retrospectively reviewed. Baseline demographics, comorbidities (quantified by modified frailty index and Charlson comorbidity index), anticoagulant/antiplatelet agent use (other than aspirin), operative details, and complications were collected. Outcomes of interest were the occurrence of postoperative hemorrhage and overdrainage.

RESULTS

A total of 234 patients were included in the study (mean age 75.22 ± 6.04 years; 66.7% male); 36 were on anticoagulation/antiplatelet therapy (excluding aspirin). This included 6 on Warfarin, 19 on direct Xa inhibitors, 10 on Clopidogrel, and 1 on both Clopidogrel and Warfarin. Notably, 70% of patients (164/234) used aspirin alone or combined with anticoagulation or clopidogrel. Baseline modified frailty index was similar between groups, but those on anticoagulant/antiplatelet therapy had a higher mean Charlson comorbidity index (2.67 ± 1.87 vs. 1.75 ± 1.84; P = 0.001). Patients on anticoagulants were more likely to experience tract hemorrhage (11.1 vs. 2.5%; P = 0.03), with no significant difference in the rates of intraventricular hemorrhage or overdrainage-related subdural fluid collection.

CONCLUSIONS

Anticoagulant and antiplatelet agents are common in the iNPH population, and patients on these agents experienced higher rates of tract hemorrhage following ventriculoperitoneal shunt placement; however, overall hemorrhagic complication rates were similar.

Development and trends in research on hypertension and atrial fibrillation: A bibliometric analysis from 2003 to 2022

BACKGROUND

This study aimed to comprehensively analyze research related to hypertension and atrial fibrillation, 2 common cardiovascular diseases with significant global public health implications, using bibliometric methods from 2003 to 2022.

METHODS

From the Web of Science Core Collection database, literature on the theme of hypertension and atrial fibrillation was retrieved. Subsequently, comprehensive bibliometric analyses were conducted across multiple dimensions utilizing software tools such as VOSviewer, Citespace, Pajek, Scimago Graphica, and ClusterProfiler. These analyses encompassed examinations of the literature according to country/region, institution, authors, journals, citation relationships, and keywords.

RESULTS

It revealed an increasing interest and shifting focus in research over the years. The analysis covered 7936 relevant publications, demonstrating a gradual rise in research activity regarding hypertension combined with atrial fibrillation over the past 2 decades, with a stable growth trend in research outcomes. Geographically, Europe and the Americas, particularly the United States, have shown the most active research in this field, while China has also gained importance in recent years. Regarding institutional contributions, internationally renowned institutions such as the University of Birmingham and the Mayo Clinic have emerged as core forces in this research direction. Additionally, Professor Lip Gregory, with his prolific research output, has stood out among numerous scholars. The American Journal of Cardiology has become a primary platform for publishing research related to hypertension and atrial fibrillation, highlighting its central role in advancing knowledge dissemination in this field. The research focus has shifted from exploring the pathophysiological mechanisms to investigating the treatment of complications and risk factors associated with hypertension and atrial fibrillation. Future research will focus on in-depth exploration of genetic and molecular mechanisms, causal relationship exploration through Mendelian randomization studies, and the application of machine learning techniques in prediction and treatment, aiming to promote the development of precision medicine for cardiovascular diseases.

CONCLUSION

In conclusion, this study provides a comprehensive overview of the developmental trajectory of research on hypertension and atrial fibrillation, presenting novel insights into trends and future research directions, thus offering information support and guidance for research in this crucial field of cardiovascular medicine.

The hospital frailty risk score effectively predicts adverse outcomes in patients with atrial fibrillation in the intensive care unit

Background

Atrial fibrillation (AF) and frailty are significant global public health problems associated with advancing age. However, the relationship between frailty and older patients with AF in the intensive care unit (ICU) has not been thoroughly investigated. This study aimed to investigate whether the hospital frailty risk score (HFRS) is associated with adverse outcomes in older patients with AF in the ICU.

Methods

This was the first retrospective analysis of older patients with AF admitted to the ICU between 2008 and 2019 at a tertiary academic medical center in Boston. The HFRS was used to measure frailty severity. The outcomes of interest were in-hospital and 30-day mortality and the incidence of sepsis and ischemic stroke.

Results

There were 7,792 participants aged approximately 80 years, almost half (44.9%) of whom were female. Among this group, 2,876 individuals were identified as non-frail, while 4,916 were classified as frail. The analysis revealed a significantly greater incidence of in-hospital (18.8% compared to 7.6%) and 30-day mortality (24.5% versus 12.3%) in the frail group. After accounting for potential confounding factors, a multivariate Cox proportional hazards regression analysis revealed that frail participants had a 1.56-fold greater risk of mortality within 30 days (95% CI = 1.38-1.76, p < 0.001).

Conclusions

Frailty is an independent risk factor for adverse outcomes in older patients with AF admitted to the ICU. Therefore, prioritizing frailty assessment and implementing specific intervention strategies to improve prognostic outcomes are recommended.

GLP-1 receptor agonists and myocardial metabolism in atrial fibrillation

Atrial fibrillation (AF) is the most common cardiac arrhythmia. Many medical conditions, including hypertension, diabetes, obesity, sleep apnea, and heart failure (HF), increase the risk for AF. Cardiomyocytes have unique metabolic characteristics to maintain adenosine triphosphate production. Significant changes occur in myocardial metabolism in AF. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have been used to control blood glucose fluctuations and weight in the treatment of type 2 diabetes mellitus (T2DM) and obesity. GLP-1RAs have also been shown to reduce oxidative stress, inflammation, autonomic nervous system modulation, and mitochondrial function. This article reviews the changes in metabolic characteristics in cardiomyocytes in AF. Although the clinical trial outcomes are unsatisfactory, the findings demonstrate that GLP-1 RAs can improve myocardial metabolism in the presence of various risk factors, lowering the incidence of AF.

The SK4 channel allosteric blocker, BA6b9, reduces atrial fibrillation substrate in rats with reduced ejection fraction

Atrial fibrillation (AF), the most common cardiac arrhythmia, is strongly associated with several comorbidities including heart failure (HF). AF in general, and specifically in the context of HF, is progressive in nature and associated with poor clinical outcomes. Current therapies for AF are limited in number and efficacy and do not target the underlying causes of atrial remodeling such as inflammation or fibrosis. We previously identified the calcium-activated SK4 K+ channels, which are preferentially expressed in the atria relative to the ventricles in both rat and human hearts, as attractive druggable target for AF treatment. Here, we examined the ability of BA6b9, a novel allosteric inhibitor of SK4 channels that targets the specific calmodulin-PIP2 binding domain, to alter AF susceptibility and atrial remodeling in a systolic HF rat postmyocardial infarction (post-MI) model. Daily BA6b9 injection (20 mg/kg/day) for 3 weeks starting 1-week post-MI prolonged the atrial effective refractory period, reduced AF induction and duration, and dramatically prevented atrial structural remodeling. In the post-MI left atrium (LA), pronounced upregulation of the SK4 K+ channel was observed, with corresponding increases in collagen deposition, α-SMA levels, and NLRP3 inflammasome expression. Strikingly, BA6b9 treatment reversed these changes while also significantly reducing the lateralization of the atrial connexin Cx43 in the LA of post-MI rats. Our findings indicate that the blockade of SK4 K+ channels using BA6b9 not only favors rhythm control but also remarkably reduces atrial structural remodeling, a property that is highly desirable for novel AF therapies, particularly in patients with comorbid HF.

Racial and Ethnic Disparities in Initiation of Direct Oral Anticoagulants Among Medicare Beneficiaries

Importance

The influence of race and ethnicity on initiation of direct oral anticoagulants (DOACs) is relatively understudied in Medicare data.

Objective

To investigate disparities in the initiation of DOACs compared with warfarin by race, ethnicity, and social vulnerability.

Design, Setting, and Participants

This retrospective cohort study used a 50% sample of Medicare fee-for-service data from January 1, 2010, to December 31, 2019 (mean patient enrollment duration, 7.7 years). Analysis took place between January 2023 and February 2024. A cohort of older adults (aged ≥65 years) with atrial fibrillation who newly initiated warfarin or DOACs (dabigatran, rivaroxaban, apixaban, and edoxaban) was identified.

Exposure

Patients were classified as non-Hispanic White, non-Hispanic Black, and Hispanic.

Main Outcomes and Measures

The likelihood of starting use of DOACs compared with warfarin was modeled, adjusting for race, ethnicity, age, sex, county-level social vulnerability, and other clinical factors.

Results

Among 950 698 anticoagulation initiations, consisting of 680 974 DOAC users and 269 724 warfarin users (mean [SD] age, 78.5 [7.6] years; 52.6% female), 5.2% were Black, 4.3% were Hispanic, and 86.7% were White. During the 10-year study period, DOAC use increased for all demographic groups. After adjustment, compared with White patients, Black patients were 23% less likely (adjusted odds ratio [AOR, 0.77; 95% CI, 0.75-0.79) and Hispanic patients were 13% less likely (AOR, 0.87; 95% CI, 0.85-0.89) to initiate DOAC use. Disparities in DOAC initiation were greatest among Black patients in the earlier years but attenuated during the study period. For instance, in 2010, the OR of Black patients initiating DOACs was 0.54 (95% CI, 0.50-0.57), attenuating linearly over time to 0.69 by 2013 (95% CI, 0.65-0.74) and 0.83 (95% CI, 0.78-0.89) by 2017. By 2019, these differences became nonsignificant (OR, 1.08; 95% CI, 0.99-1.18).

Conclusions and Relevance

In this cohort study of Medicare patients with atrial fibrillation, Black and Hispanic patients were less likely to initiate DOACs for atrial fibrillation, although these differences diminished over time. Identifying the factors behind these early disparities is crucial for ensuring equitable access to novel therapies as they emerge for Black and Hispanic populations.

Exenatide reduces atrial fibrillation susceptibility by inhibiting hKv1.5 and hNav1.5 channels

Exenatide, a promising cardioprotective agent, protects against cardiac structural remodeling and diastolic dysfunction. Combined blockade of sodium and potassium channels is valuable for managing atrial fibrillation (AF). Here, we explored whether exenatide displayed anti-AF effects by inhibiting human Kv1.5 and Nav1.5 channels. We used the whole-cell patch-clamp technique to investigate the effects of exenatide on hKv1.5 and hNav1.5 channels expressed in human embryonic kidney 293 cells and studied the effects of exenatide on action potential (AP) and other cardiac ionic currents in rat atrial myocytes. Additionally, an electrical mapping system was used to explore the effects of exenatide on electrical properties and AF activity in isolated rat hearts. Finally, a rat AF model, established using acetylcholine and calcium chloride, was employed to evaluate the anti-AF potential of exenatide in rats. Exenatide reversibly suppressed IKv1.5 with IC50 of 3.08 μM, preferentially blocked the hKv1.5 channel in its closed state, and positively shifted the voltage-dependent activation curve. Exenatide also reversibly inhibited INav1.5 with IC50 of 3.30 μM, negatively shifted the voltage-dependent inactivation curve, and slowed its recovery from inactivation with significant use-dependency at 5 and 10 Hz. Furthermore, exenatide prolonged AP duration and suppressed the sustained K+ current (Iss) and transient outward K+ current (Ito), but without inhibition of L-type Ca2+ current (ICa,L) in rat atrial myocytes. Exenatide prevented AF incidence and duration in rat hearts and rats. These findings demonstrate that exenatide inhibits IKv1.5 and INav1.5in vitro and reduces AF susceptibility in isolated rat hearts and rats.

Effect of different oral anticoagulants on cognitive function in patients with atrial fibrillation: A Bayesian network meta-analysis

BACKGROUND

Atrial fibrillation (AF) is 1 of the most common types of arrhythmias. At present, the treatment for patients with AF mainly includes oral anticoagulants (OACs). Studies have shown that OACs are associated with cognitive decline in patients with atrial fibrillation; however, there is a lack of relevant evidence. This study used Bayesian network meta-analysis (NMA) to investigate the effects of different oral anticoagulants on cognitive decline in patients with AF.

METHODS

We systematically searched for clinical studies on oral anticoagulants in patients with AF in PubMed, Web of Science, Embase, and the Cochrane Library as of July 3, 2023. Cochrane's randomized controlled trial bias risk assessment tool and the Newcastle-Ottawa Scale were used to assess the bias risk of the included studies. The main outcome measure was decreased cognitive functioning.

RESULTS

Ten studies were included, including 2 RCTs and 7 RCSs, including 882,847 patients with AF. Five oral anticoagulants and 2 anticoagulants were included: VKAs (especially warfarin), Dabigatran, Edoxaban, Rivaroxaban, Apixaban, and Aspirin, Clopidogrel. The results of the mesh meta-analysis showed that VKAs were superior to warfarin in reducing the risk of cognitive decline in patients with AF (OR = -1.19, 95% CI (-2.35, -0.06), P < .05) (Table 5). The top 3 drugs in terms of the probability of reducing the incidence of cognitive impairment in patients with AF with different oral anticoagulants were VKAs (87%), rivaroxaban (62.2%), and dabigatran (60.8%).

CONCLUSION

Based on the results of this study, VKAs may be the best intervention measure for reducing the risk of cognitive decline in patients with AF. Owing to the limitations of this study, more high-quality randomized controlled trials with large sample sizes and multiple centers are required to provide more evidence.

Analyses of lncRNA and mRNA profiles in recurrent atrial fibrillation after catheter ablation

BACKGROUND

Atrial fibrillation (AF) is the most common cardiac arrhythmia worldwide. Catheter ablation has become a crucial treatment for AF. However, there is a possibility of atrial fibrillation recurrence after catheter ablation. Our study sought to elucidate the role of lncRNA‒mRNA regulatory networks in late AF recurrence after catheter ablation.

METHODS

We conducted RNA sequencing to profile the transcriptomes of 5 samples from the presence of recurrence after AF ablation (P-RAF) and 5 samples from the absence of recurrence after AF ablation (A-RAF). Differentially expressed genes (DEGs) and long noncoding RNAs (DE-lncRNAs) were analyzed using the DESeq2 R package. The functional correlations of the DEGs were assessed through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. A protein‒protein interaction (PPI) network was constructed using STRING and Cytoscape. We also established a lncRNA‒mRNA regulatory network between DE-lncRNAs and DEGs using BEDTools v2.1.2 software and the Pearson correlation coefficient method. To validate the high-throughput sequencing results of the hub genes, we conducted quantitative real-time polymerase chain reaction (qRT‒PCR) experiments.

RESULTS

A total of 28,528 mRNAs and 42,333 lncRNAs were detected. A total of 96 DEGs and 203 DE-lncRNAs were identified between the two groups. GO analysis revealed that the DEGs were enriched in the biological processes (BPs) of "regulation of immune response" and "regulation of immune system process", the cellular components (CCs) of "extracellular matrix" and "cell‒cell junction", and the molecular functions (MFs) of "signaling adaptor activity" and "protein-macromolecule adaptor activity". According to the KEGG analysis, the DEGs were associated with the "PI3K-Akt signaling pathway" and "MAPK signaling pathway." Nine hub genes (MMP9, IGF2, FGFR1, HSPG2, GZMB, PEG10, GNLY, COL6A1, and KCNE3) were identified through the PPI network. lncRNA-TMEM51-AS1-201 was identified as a core regulator in the lncRNA‒mRNA regulatory network, suggesting its potential impact on the recurrence of AF after catheter ablation through the regulation of COL6A1, FGFR1, HSPG2, and IGF2.

CONCLUSIONS

The recurrence of atrial fibrillation after catheter ablation may be associated with immune responses and fibrosis, with the extracellular matrix playing a crucial role. TMEM51-AS1-201 has been identified as a potential key target for AF recurrence after catheter ablation.

Assessment and Management of Atrial Fibrillation in Older Adults with Frailty

Atrial fibrillation (AF) is a major driver of morbidity and mortality among older adults with frailty. Moreover, frailty is highly prevalent in older adults with AF. Understanding and addressing the needs of frail older adults with AF is imperative to guide clinicians caring for older adults. In this review, we summarize current evidence to support the assessment and management of older adults with AF and frailty, incorporating numerous recent landmark trials and studies in the context of the 2023 US AF guideline.

Association between triglyceride-glucose index trajectories and radiofrequency ablation outcomes in patients with stage 3D atrial fibrillation

BACKGROUND

This study investigates the relationship between triglyceride-glucose (TyG) index trajectories and the results of ablation in patients with stage 3D atrial fibrillation (AF).

METHODS

A retrospective cohort study was carried out on patients who underwent AF Radiofrequency Catheter Ablation (RFCA) at the Cardiology Department of the Fourth Affiliated Hospital of Zhejiang University and Taizhou Hospital of Zhejiang Province from January 2016 to December 2022. The main clinical endpoint was determined as the occurrence of atrial arrhythmia for at least 30 s following a 3-month period after ablation. Using a latent class trajectory model, different trajectory groups were identified based on TyG levels. The relationship between TyG trajectory and the outcome of AF recurrence in patients was assessed through Kaplan-Meier survival curve analysis and multivariable Cox proportional hazards regression model.

RESULTS

The study included 997 participants, with an average age of 63.21 ± 9.84 years, of whom 630 were males (63.19%). The mean follow-up period for the participants was 30.43 ± 17.75 months, during which 200 individuals experienced AF recurrence. Utilizing the minimum Bayesian Information Criterion (BIC) and the maximum Entropy principle, TyG levels post-AF RFCA were divided into three groups: Locus 1 low-low group (n = 791), Locus 2 low-high-low group (n = 14), and Locus 3 high-high group (n = 192). Significant differences in survival rates among the different trajectories were observed through the Kaplan-Meier curve (P < 0.001). Multivariate Cox regression analysis showed a significant association between baseline TyG level and AF recurrence outcomes (HR = 1.255, 95% CI: 1.087-1.448). Patients with TyG levels above 9.37 had a higher risk of adverse outcomes compared to those with levels below 8.67 (HR = 2.056, 95% CI: 1.335-3.166). Furthermore, individuals in Locus 3 had a higher incidence of outcomes compared to those in Locus 1 (HR = 1.580, 95% CI: 1.146-2).

CONCLUSION

The TyG trajectories in patients with stage 3D AF are significantly linked to the outcomes of AF recurrence. Continuous monitoring of TyG levels during follow-up may help in identifying patients at high risk of AF recurrence, enabling the early application of effective interventions.

Atrial fibrosis heterogeneity is a risk for atrial fibrillation in pigs with ischaemic heart failure

BACKGROUND

Atrial fibrillation (AF) is the most common arrhythmia and is associated with considerable morbidity and mortality. Ischaemic heart failure (IHF) remains one of the most common causes of AF in clinical practice. However, ischaemia-mediated mechanisms leading to AF are still incompletely understood, and thus, current treatment approaches are limited. To improve our understanding of the pathophysiology, we studied a porcine IHF model.

METHODS

In pigs, IHF was induced by balloon occlusion of the left anterior descending artery for 90 min. After 30 days of reperfusion, invasive haemodynamic measurements and electrophysiological studies were performed. Masson trichrome and immunofluorescence staining were conducted to assess interstitial fibrosis and myofibroblast activation in different heart regions.

RESULTS

After 30 days of reperfusion, heart failure with significantly reduced ejection fraction (left anterior obique 30°, 34.78 ± 3.29% [IHF] vs. 62.03 ± 2.36% [control], p < .001; anterior-posterior 0°, 29.16 ± 3.61% vs. 59.54 ± 1.09%, p < .01) was observed. These pigs showed a significantly higher susceptibility to AF (33.90% [IHF] vs. 12.98% [control], p < .05). Histological assessment revealed aggravated fibrosis in atrial appendages but not in atrial free walls in IHF pigs (11.13 ± 1.44% vs. 5.99 ± .86%, p < .01 [LAA], 8.28 ± .56% vs. 6.01 ± .35%, p < .01 [RAA]), which was paralleled by enhanced myofibroblast activation (12.09 ± .65% vs. 9.00 ± .94%, p < .05 [LAA], 14.37 ± .60% vs. 10.30 ± 1.41%, p < .05 [RAA]). Correlation analysis indicated that not fibrosis per se but its cross-regional heterogeneous distribution across the left atrium was associated with AF susceptibility (r = .6344, p < .01).

CONCLUSION

Our results suggest that left atrial cross-regional fibrosis difference rather than overall fibrosis level is associated with IHF-related AF susceptibility, presumably by establishing local conduction disturbances and heterogeneity.

Cardiac resident macrophages: Spatiotemporal distribution, development, physiological functions, and their translational potential on cardiac diseases

Cardiac resident macrophages (CRMs) are the main population of cardiac immune cells. The role of these cells in regeneration, functional remodeling, and repair after cardiac injury is always the focus of research. However, in recent years, their dynamic changes and contributions in physiological states have a significant attention. CRMs have specific phenotypes and functions in different cardiac chambers or locations of the heart and at different stages. They further show specific differentiation and development processes. The present review will summarize the new progress about the spatiotemporal distribution, potential developmental regulation, and their roles in cardiac development and aging as well as the translational potential of CRMs on cardiac diseases. Of course, the research tools for CRMs, their respective advantages and disadvantages, and key issues on CRMs will further be discussed.

Data-driven classification of left atrial morphology and its predictive impact on atrial fibrillation catheter ablation

INTRODUCTION

Various left atrial (LA) anatomical structures are correlated with postablative recurrence for atrial fibrillation (AF) patients. Comprehensively integrating anatomical structures, digitizing them, and implementing in-depth analysis, which may supply new insights, are needed. Thus, we aim to establish an interpretable model to identify AF patients' phenotypes according to LA anatomical morphology, using machine learning techniques.

METHODS AND RESULTS

Five hundred and nine AF patients underwent first ablation treatment in three centers were included and were followed-up for postablative recurrent atrial arrhythmias. Data from 369 patients were regarded as training set, while data from another 140 patients, collected from different centers, were used as validation set. We manually measured 57 morphological parameters on enhanced computed tomography with three-dimensional reconstruction technique and implemented unsupervised learning accordingly. Three morphological groups were identified, with distinct prognosis according to Kaplan-Meier estimator (p < .001). Multivariable Cox model revealed that morphological grouping were independent predictors of 1-year recurrence (Group 1: HR = 3.00, 95% CI: 1.51-5.95, p = .002; Group 2: HR = 4.68, 95% CI: 2.40-9.11, p < .001; Group 3 as reference). Furthermore, external validation consistently demonstrated our findings.

CONCLUSIONS

Our study illustrated the feasibility of employing unsupervised learning for the classification of LA morphology. By utilizing morphological grouping, we can effectively identify individuals at different risks of postablative recurrence and thereby assist in clinical decision-making.

Determining The Risk of Atrial Fibrillation Paroxysm in Patients With Chronic Heart Failure With Intact and Reduced Ejection Fraction

AIM

To determine predictors for the development of atrial fibrillation (AF) in patients with chronic heart failure (CHF) with preserved and reduced ejection fraction by echocardiography (EchoCG) according to an extended protocol with determination of diastolic function and left atrial global strain.

MATERIAL AND METHODS

Data of 168 patients with stage I-III CHF without a history of AF were analyzed. All patients underwent echocardiography according to an extended protocol with the determination of diastolic dysfunction (DD), left atrial ejection fraction (LA EF), and left atrial global strain (LA GS). Tissue Doppler imaging (TDI) was used to evaluate the early (E) and late (A) LV filling velocity and the early (E') and late (A') diastolic mitral annular velocity. In all patients, Holter ECG monitoring (HM ECG) of heart rhythm was performed for 3 days, and ECG monitoring with telemedicine technologies was performed for 7 days, 3 times a day for 3 minutes. The follow-up period was 3 months or until an AF episode.

RESULTS

During the study, paroxysmal AF (pAF) was detected in 41 (24.4%) patients using various methods of heart rhythm monitoring. Complaints of palpitations were noted for 10 (24.4%) patients during pAF, which was recorded using a CardioQVARK® device, HM ECG or a 12-lead ECG. In 5 (12.2%) patients, daily ECG monitoring revealed pAF without associated complaints. HM ECG detected 8, 2, 4 (19.5%, 4.8%, and 9.7%) cases during 24, 48 and 72 hours, respectively; a single-channel CardioQVARK® detected 30 (73.2%) cases when used 3 times a day for 7 days. These results showed that AF frequently develops in CHF without accompanying symptoms. The method for detecting pAF with CardioQVARK® showed good results: it was twice more effective than HM ECG and three times more effective than 12-lead ECG. Also, according to ultrasound data, significant changes in the following parameters were noted in patients with AF: LA EF <36% (OR 1.04, 95% CI: 1.02-1.08), p=0.003; LA GS <9.9% (OR 1.16, 95% CI: 1.02-1.38), p<0.001; TDI E med <5.7 cm/s (OR 0.97, 95% CI: 0.94-1.00), p=0.026. Grade 2 DD did not show statistically significant results (OR 1.1, 95% CI: 0.7-1.5, p=0.54). However, it was detected more frequently in patients with AF, in 34% of cases, compared to 29% of cases in patients without AF, which requires further study on a larger patient sample.

CONCLUSION

Patients with CHF have a high risk of developing pAF (24.4%). 75% of patients with AF do not feel the development of paroxysm. All CHF patients should undergo EchoCG with assessment of LA EF, TDI E med and LA GS to identify a group at risk for the development of AF. Heart rhythm remote monitoring with CardioQVARK® devices can be considered a reliable method for early detection of pAF and timely initiation of anticoagulant therapy in patients with CHF.

Application of a circular-shaped pulsed field ablation catheter with magnetic sensors for pulmonary vein isolation: a multi-centre clinical study report

AIMS

A few studies have reported the effect and safety of pulsed field ablation (PFA) catheters for ablating atrial fibrillation (AF), which were mainly based on basket-shaped or flower-shaped designs. However, the clinical application of a circular-shaped multi-electrode catheter with magnetic sensors is very limited. To study the efficacy and safety of a PFA system in patients with paroxysmal AF using a circular-shaped multi-electrode catheter equipped with magnetic sensors for pulmonary vein isolation (PVI).

METHODS AND RESULTS

A novel proprietary bipolar PFA system was used for PVI, which utilized a circular-shaped multi-electrode catheter with magnetic sensors and allowed for three-dimensional model reconstruction, mapping, and ablation in one map. To evaluate the efficacy, efficiency, and safety of this PFA system, a prospective, multi-centre, single-armed, pre-market clinical study was performed. From July 2021 to December 2022, 151 patients with paroxysmal AF were included and underwent PVI. The study examined procedure time, immediate success rate, procedural success rate at 12 months, and relevant complications. In all 151 patients, all the pulmonary veins were acutely isolated using the studied system. Pulsed field ablation delivery was 78.4 ± 41.8 times and 31.3 ± 16.7 ms per patient. Skin-to-skin procedure time was 74.2 ± 29.8 min, and fluoroscopy time was 13.1 ± 7.6 min. The initial 11 (7.2%) cases underwent procedures with deep sedation anaesthesia, and the following cases underwent local anaesthesia. In the initial 11 cases, 4 cases (36.4%) presented transient vagal responses, and the rest were all successfully preventatively treated with atropine injection and rapid fluid infusion. No severe complications were found during or after the procedure. During follow-up, 3 cases experienced atrial flutter, and 11 cases had AF recurrence. The estimated 12-month Kaplan-Meier of freedom from arrhythmia was 88.4%.

CONCLUSION

The PFA system, comprised of a circular PFA catheter with magnetic sensors, could rapidly achieve PVI under three-dimensional guidance and demonstrated excellent safety with comparable effects.

Inhibitory effect of aloperine on transient outward potassium currents in rat cardiac myocytes

Objective

Aloperine (ALO) is an effective quinolizidine alkaloid. Previous research has demonstrated its antiarrhythmic effect by inhibiting voltage-gated sodium currents in rat ventricular myocytes. This study explored its effect on transient outward potassium currents (Ito) in rat atrial myocytes to identify potential targets in the context of ion channel currents.

Methods

The Ito characteristics in rat atrial myocytes were recorded using a whole-cell patch-clamp technique. Molecular docking was performed to validate ligand-protein binding interactions.

Results

ALO at concentrations of 3 and 10 μM significantly reduced Ito current densities. Gating kinetics analysis revealed ALO's ability to slow Ito activation, hasten inactivation, and prolong transition from inactive to resting state. Molecular docking revealed that ALO could stably bind to KCND2.

Conclusion

ALO may inhibit Ito by slowing the activation process, accelerating inactivation, and delaying the recovery time after inactivation, potentially preventing acetylcholine-induced AF.

Pulmonary vein dose and risk of atrial fibrillation in patients with non-small cell lung cancer following definitive radiotherapy: An NI-HEART analysis

BACKGROUND AND PURPOSE

Symptomatic arrhythmia is common following radiotherapy for non-small cell lung cancer (NSCLC), frequently resulting in morbidity and hospitalization. Modern treatment planning technology theoretically allows sparing of cardiac substructures. Atrial fibrillation (AF) comprises the majority of post-radiotherapy arrhythmias, but efforts to prevent this cardiotoxicity have been limited as the causative cardiac substructure is not known. In this study we investigated if incidental radiation dose to the pulmonary veins (PVs) is associated with AF.

MATERIAL AND METHODS

A single-centre study of patients completing contemporary (chemo)radiation for NSCLC, with modern planning techniques. Oncology, cardiology and death records were examined, and AF events were verified by a cardiologist. Cardiac substructures were contoured on planning scans for retrospective dose analysis.

RESULTS

In 420 eligible patients with NSCLC treated with intensity-modulated (70%) or 3D-conformal (30%) radiotherapy with a median OS of 21.8 months (IQR 10.8-35.1), there were 26 cases of new AF (6%). All cases were grade 3 except two cases of grade 4. Dose metrics for both the left (V55) and right (V10) PVs were associated with the incidence of new AF. Metrics remained statistically significant after accounting for the competing risk of death and cardiovascular covariables for both the left (HR 1.02, 95%CI 1.00-1.03, p = 0.005) and right (HR 1.01 (95%CI 1.00-1.02, p = 0.033) PVs.

CONCLUSION

Radiation dose to the PVs during treatment of NSCLC was associated with the onset of AF. Actively sparing the PVs during treatment planning could reduce the incidence of AF during follow-up, and screening for AF may be warranted for select cases.

New-onset atrial fibrillation in seropositive rheumatoid arthritis: association with disease-modifying anti-rheumatic drugs treatment

OBJECTIVE

Atrial fibrillation (AF) is a potentially lethal complication that leads to increased hospitalization, disability and mortality. Furthermore, the risk of cardiovascular disease is increased in RA. We evaluated whether DMARD treatment is associated with incident AF in patients with seropositive RA (SPRA).

METHODS

The South Korean Health Insurance Review and Assessment Service database was used to identify patients newly diagnosed with SPRA between 2010 and 2020. A nested case-control analysis was performed to match AF-affected patients to unaffected controls for age, sex, follow-up duration, and index year of SPRA diagnosis at a 1:4 ratio. Adjusted conditional logistic regression was used to identify the predictive factors for AF.

RESULTS

Of the 108 085 patients with SPRA, 2,629 (2.4%) developed new-onset AF, and the proportion of females was ∼67%. In the matched population, pre-existing comorbidities of hypertension, chronic kidney disease, and heart failure were associated with increased risk of AF. Meanwhile, the use of methotrexate (MTX) decreased the risk of incident AF [adjusted odds ratio (aOR), 0.89], whereas the use of leflunomide (LEF) increased AF (aOR, 1.21). In a subgroup of patients aged ≥50 years, LEF and adalimumab increased the occurrence of AF, while MTX decreased AF in males and LEF increased this risk in females.

CONCLUSION

Although the number of subjects developing new-onset AF was small, MTX decreased and LEF increased incident AF in patients with RA. Especially, a distinct pattern of AF risk with DMARDs usage was observed according to age and sex.

Combination of frequency- and time-domain characteristics of the fibrillatory waves for enhanced prediction of persistent atrial fibrillation recurrence after catheter ablation

Catheter ablation (CA) remains the cornerstone alternative to cardioversion for sinus rhythm (SR) restoration in patients with atrial fibrillation (AF). Unfortunately, despite the last methodological and technological advances, this procedure is not consistently effective in treating persistent AF. Beyond introducing new indices to characterize the fibrillatory waves (f-waves) recorded through the preoperative electrocardiogram (ECG), the aim of this study is to combine frequency- and time-domain features to improve CA outcome prediction and optimize patient selection for the procedure, given the absence of any study that jointly analyzes information from both domains. Precisely, the f-waves of 151 persistent AF patients undergoing their first CA procedure were extracted from standard V1 lead. Novel spectral and amplitude features were derived from these waves and combined through a machine learning algorithm to anticipate the intervention mid-term outcome. The power rate index (φ), which estimates the power of the harmonic content regarding the dominant frequency (DF), yielded the maximum individual discriminant ability of 64% to discern between individuals who experienced a recurrence of AF and those who sustained SR after a 9-month follow-up period. The predictive accuracy was improved up to 78.5% when this parameter φ was merged with the amplitude spectrum area in the DF bandwidth (A M S A L F ) and the normalized amplitude of the f-waves into a prediction model based on an ensemble classifier, built by random undersampling boosting of decision trees. This outcome suggests that the synthesis of both spectral and temporal features of the f-waves before CA might enrich the prognostic knowledge of this therapy for persistent AF patients.

Zbtb16 increases susceptibility of atrial fibrillation in type 2 diabetic mice via Txnip-Trx2 signaling

Atrial fibrillation (AF) is the most prevalent sustained cardiac arrhythmia, and recent epidemiological studies suggested type 2 diabetes mellitus (T2DM) is an independent risk factor for the development of AF. Zinc finger and BTB (broad-complex, tram-track and bric-a-brac) domain containing 16 (Zbtb16) serve as transcriptional factors to regulate many biological processes. However, the potential effects of Zbtb16 in AF under T2DM condition remain unclear. Here, we reported that db/db mice displayed higher AF vulnerability and Zbtb16 was identified as the most significantly enriched gene by RNA sequencing (RNA-seq) analysis in atrium. In addition, thioredoxin interacting protein (Txnip) was distinguished as the key downstream gene of Zbtb16 by Cleavage Under Targets and Tagmentation (CUT&Tag) assay. Mechanistically, increased Txnip combined with thioredoxin 2 (Trx2) in mitochondrion induced excess reactive oxygen species (ROS) release, calcium/calmodulin-dependent protein kinase II (CaMKII) overactivation, and spontaneous Ca2+ waves (SCWs) occurrence, which could be inhibited through atrial-specific knockdown (KD) of Zbtb16 or Txnip by adeno-associated virus 9 (AAV9) or Mito-TEMPO treatment. High glucose (HG)-treated HL-1 cells were used to mimic the setting of diabetic in vitro. Zbtb16-Txnip-Trx2 signaling-induced excess ROS release and CaMKII activation were also verified in HL-1 cells under HG condition. Furthermore, atrial-specific Zbtb16 or Txnip-KD reduced incidence and duration of AF in db/db mice. Altogether, we demonstrated that interrupting Zbtb16-Txnip-Trx2 signaling in atrium could decrease AF susceptibility via reducing ROS release and CaMKII activation in the setting of T2DM.

The association between triglyceride glucose-body mass index and all-cause mortality in critically ill patients with atrial fibrillation: a retrospective study from MIMIC-IV database

BACKGROUND

The TyG-BMI index, which is a reliable indicator of insulin resistance (IR), has been found to have a significant correlation with the occurrence of cardiovascular events. However, there still lacks study on the TyG-BMI index and prognosis in patients with atrial fibrillation (AF). The objective of the present study was to evaluate the relationship between TyG-BMI index at admission to ICU and all-cause mortality in critically ill patients with AF.

METHODS

The patient's data were extracted from Medical Information Mart for Intensive Care IV(MIMIC-IV) database. All patients were divided into four groups according to TyG-BMI index. Outcomes include primary and secondary endpoints, with the primary endpoint being the 30-day and 365-day all-cause mortality and the secondary endpoint being the 90-day and 180-day all-cause mortality. TyG-BMI index was quartile and Kaplan-Meier curve was used to compare the outcome of each group. Cox proportional-hazards regression model and restricted cubic splines (RCS) were conducted to assess the relationship between TyG-BMI index and outcomes.

RESULTS

Out of a total of 2509 participants, the average age was 73.26 ± 11.87 years, with 1555 (62.0%) being males. Patients with lower level of TyG-BMI had higher risk of 30-day, 90-day, 180-day and 365-day all-cause mortality, according to the Kaplan-Meier curves (log-rank P < 0.001). In addition, cox proportional-hazards regression analysis revealed that the risk of 30-day, 90-day, 180-day and 365-day all-cause mortality was significantly higher in the lowest quartile of TyG-BMI. Meanwhile, the RCS analysis indicated that L-typed relationships between TyG-BMI index and all-cause mortality, with inflection points at 223.60 for 30-day and 255.02 for 365-day all-cause mortality, respectively. Compared to patients with TyG-BMI levels below the inflection points, those with higher levels had a 1.8% lower risk for 30-day all-cause mortality (hazard ratio [HR] 0.982, 95% confidence interval [CI] 0.9676-0.988) and 1.1% lower risk for 365-day all-cause mortality (HR 0.989, 95% CI 0.986-0.991).

CONCLUSION

In critically ill patients with AF, a lower TyG-BMI level is significantly associated with a higher risk of 30-day, 90-day, 180-day and 365-day all-cause mortality. TyG-BMI index could be used as a valid indicator for grading and treating patients with AF in the ICU.

The Role of Immune Cells Driving Electropathology and Atrial Fibrillation

Atrial fibrillation (AF) is the most common progressive cardiac arrhythmia worldwide and entails serious complications including stroke and heart failure. Despite decades of clinical research, the current treatment of AF is suboptimal. This is due to a lack of knowledge on the mechanistic root causes of AF. Prevailing theories indicate a key role for molecular and structural changes in driving electrical conduction abnormalities in the atria and as such triggering AF. Emerging evidence indicates the role of the altered atrial and systemic immune landscape in driving this so-called electropathology. Immune cells and immune markers play a central role in immune remodeling by exhibiting dual facets. While the activation and recruitment of immune cells contribute to maintaining atrial stability, the excessive activation and pronounced expression of immune markers can foster AF. This review delineates shifts in cardiac composition and the distribution of immune cells in the context of cardiac health and disease, especially AF. A comprehensive exploration of the functions of diverse immune cell types in AF and other cardiac diseases is essential to unravel the intricacies of immune remodeling. Usltimately, we delve into clinical evidence showcasing immune modifications in both the atrial and systemic domains among AF patients, aiming to elucidate immune markers for therapy and diagnostics.

Associations of Dietary and Lifestyle Components with Atrial Fibrillation

Atrial fibrillation (AF) is a prevalent cardiac arrhythmia that still remains a significant health concern, especially due to its consequences, including stroke and heart failure. This review explores the intricate interplay between AF, lifestyle choices, and dietary habits. It is particularly focused on findings from diverse studies about non-pharmacological methods of managing AF. Moreover, its purpose is to elucidate the implementation of lifestyle changes such as physical activity or proper diet choices in the integrated treatment strategy of patients with AF.

Blockchain technology in Cardiovascular Medicine: a glance to the future? Results from a social media survey and future perspectives

The leverage of digital facilities in medicine for disease diagnosis, monitoring, and medical history recording has become increasingly pivotal. However, the advancement of these technologies poses a significant challenge regarding data privacy, given the highly sensitive nature of medical information. In this context, the application of Blockchain technology, a digital system where information is stored in blocks and each block is linked to the one before, has the potential to enhance existing technologies through its exceptional security and transparency. This paradigm is of particular importance in cardiovascular medicine, where the prevalence of chronic conditions leads to the need for secure remote monitoring, secure data storage and secure medical history updating. Indeed, digital support for chronic cardiovascular pathologies is getting more and more crucial. This paper lays its rationale in three primary aims: 1) to scrutinize the existing literature for tangible applications of blockchain technology in the field of cardiology; 2) to report results from a survey aimed at gauging the reception of blockchain technology within the cardiovascular community, conducted on social media; 3) to conceptualize a web application tailored specifically to cardiovascular care based on blockchain technology. We believe that Blockchain technology may contribute to a breakthrough in healthcare digitalization, especially in the field of cardiology; in this context, we hope that the present work may be inspiring for physicians and healthcare stakeholders.

The Association Between Urbanization and Electrocardiogram Abnormalities in China: a Nationwide Longitudinal Study

The health effects of urbanization are controversial. The association between urbanization and reversible subclinical risks of cardiovascular diseases (e.g., electrocardiogram (ECG) abnormalities) has rarely been studied. This study aimed to assess the association between urbanization and ECG abnormalities in China based on the China National Stroke Screening Survey (CNSSS). We used changes in the satellite-measured impervious surfaces rate and nighttime light data to assess the level of urbanization. Every interquartile increment in the impervious surfaces rate or nighttime light was related to a decreased risk of ECG abnormalities, with odds ratios of 0.894 (95% CI, 0.869-0.920) or 0.809 (95% CI, 0.772-0.847), respectively. And we observed a U-shaped nonlinear exposure-response relationship curve between the impervious surfaces rate and ECG abnormalities. In conclusion, the current average level of urbanization among the studied Chinese adults remains a beneficial factor for reducing cardiovascular risks.

Drug-induced atrial fibrillation. A narrative review of a forgotten adverse effect

Atrial fibrillation (AF) is the most common cardiac arrhythmia and is associated with an increased morbidity and mortality. There is clinical evidence that an increasing number of cardiovascular and non-cardiovascular drugs, mainly anticancer drugs, can induce AF either in patients with or without pre-existing cardiac disorders, but drug-induced AF (DIAF) has not received the attention that it might deserve. In many cases DIAF is asymptomatic and paroxysmal and patients recover sinus rhythm spontaneously, but sometimes, DIAF persists, and it is necessary to perform a cardioversion. Furthermore, DIAF is not mentioned in clinical guidelines on the treatment of AF. The risk of DIAF increases in elderly and in patients treated with polypharmacy and with risk factors and comorbidities that commonly coexist with AF. This is the case of cancer patients. Under these circumstances ascribing causality of DIAF to a given drug often represents a clinical challenge. We review the incidence, the pathophysiological mechanisms, risk factors, clinical relevance, and treatment of DIAF. Because of the limited information presently available, further research is needed to obtain a deeper insight into DIAF. Meanwhile, it is important that clinicians are aware of the problem that DIAF represents, recognize which drugs may cause DIAF, and consider the possibility that a drug may be responsible for a new-onset AF episode.

Overcoming Uncertainties in Electrogram-Based Atrial Fibrillation Mapping: A Review

In clinical rhythmology, intracardiac bipolar electrograms (EGMs) play a critical role in investigating the triggers and substrates inducing and perpetuating atrial fibrillation (AF). However, the interpretation of bipolar EGMs is ambiguous due to several aspects of electrodes, mapping algorithms and wave propagation dynamics, so it requires several variables to describe the effects of these uncertainties on EGM analysis. In this narrative review, we critically evaluate the potential impact of such uncertainties on the design of cardiac mapping tools on AF-related substrate characterization. Literature suggest uncertainties are due to several variables, including the wave propagation vector, the wave's incidence angle, inter-electrode spacing, electrode size and shape, and tissue contact. The preprocessing of the EGM signals and mapping density will impact the electro-anatomical representation and the features extracted from the local electrical activities. The superposition of multiple waves further complicates EGM interpretation. The inclusion of these uncertainties is a nontrivial problem but their consideration will yield a better interpretation of the intra-atrial dynamics in local activation patterns. From a translational perspective, this review provides a concise but complete overview of the critical variables for developing more precise cardiac mapping tools.

Development and validation a nomogram for predicting new-onset postoperative atrial fibrillation following pulmonary resection

BACKGROUND

The new-onset postoperative atrial fibrillation (NOPAF) following pulmonary resection is a common clinical concern. The aim of this study was to construct a nomogram to intuitively predict the risk of NOPAF and offered protective treatments.

METHODS

Patients who underwent pulmonary resection between January 2018 and December 2020 were consecutively enrolled. Forward stepwise multivariable logistic regression analyses were used to screen independent predictors, and a derived nomogram model was built. The model performance was evaluated in terms of calibration, discrimination and clinical utility and validated with bootstrap resampling.

RESULTS

A total of 3583 patients who met the research criteria were recruited for this study. The incidence of NOPAF was 1.507% (54/3583). A nomogram, composed of five independent predictors, namely age, admission heart rate, extent of resection, laterality, percent maximum ventilation volume per minute (%MVV), was constructed. The concordance index (C-index) was 0.811. The nomogram showed substantial discriminative ability, with an area under the receiver operating characteristic curve of 0.811 (95% CI 0.758-0.864). Moreover, the model shows prominent calibration performance and higher net clinical benefits.

CONCLUSION

We developed a novel nomogram that can predict the risk of NOPAF following pulmonary resection, which may assist clinicians predict the individual probability of NOPAF and perform available prophylaxis. By using bootstrap resampling for validation, the optimal discrimination and calibration were demonstrated, indicating that the nomogram may have clinical practicality.

Left Atrial Appendage Occlusion and Post-procedural Antithrombotic Management

Left atrial appendage occlusion (LAAO) is an established alternative to oral anticoagulation for stroke prevention in atrial fibrillation. Antithrombotic therapy is used in the post-procedural period to prevent device-related thrombosis (DRT). The risk of DRT is considered highest in the first 45-90 days after device implantation, based on animal studies of the device healing process. Clinically applied antithrombotic regimens vary greatly across studies, continents, and centers. This article gives an overview of the evidence behind current antithrombotic regimens, ongoing randomized trials, and future post-procedural management.

Soluble PILRα: A novel plasma biomarker for atrial fibrillation progression and recurrence after catheter ablation

BACKGROUND

We aimed to identify plasma biomarkers of atrial fibrillation (AF) progression and recurrence after catheter ablation.

METHODS

Using AF gene profiling data from GEO database, a weighted gene co-expression network analysis (WGCNA) was conducted to determine the most significant module and hub genes associated with AF. Subsequently, 318 consecutively admitted patients who had undergone radiofrequency catheter ablation were enrolled in this study.

RESULTS

WGCNA results revealed that paired immunoglobulin-like type 2 receptor alpha (PILRA) was the only black module gene highly correlated with clinical traits. Plasma soluble PILRα (sPILRα) levels were elevated in patients with AF and significantly elevated in patients with persistent versus paroxysmal AF (4.64 ± 2.74 vs. 3.04 ± 1.56 ng/mL, p < 0.001). Elevated sPILRα level was an independent risk factor for AF progression even after adjusting for traditional factors (adjusted odds ratio: 3.06, 95 % confidence interval [CI]: 1.88-5.27, p < 0.001) and AF recurrence after catheter ablation in patients with persistent AF (adjusted hazards ratio: 4.41, 95 % CI: 1.22-15.92, p = 0.023).

CONCLUSIONS

WGCNA screening of GEO microarray gene profiling data showed PILRA expression levels to be correlated with AF progression and recurrence after catheter ablation in patients with persistent AF.

Predictive value of soluble suppression of tumorigenicity 2 in atrial fibrillation: a systematic review and meta-analysis

Purpose

Atrial fibrosis is the main pathological basis for the pathogenesis and progression of atrial fibrillation (AF). Soluble suppression of tumorigenicity 2 (sST2) is involved in fibrosis. Recent studies have explored its predictive value in AF outcomes. We performed this study to assess whether sST2 is an independent biomarker of AF outcomes and explore the potential mechanism.

Methods

PubMed, Web of Science, EMBASE, and Cochrane Library databases were searched systematically from inception through July 1, 2023, to identify relevant studies. Outcomes of interest included occurrence, recurrence, and major adverse cardiac events (MACEs) of AF. This meta-analysis was reported following the criteria outlined in PRISMA 2020, and the protocol was registered in PROSPERO (number: CRD42023459789). All statistical analyses were performed using the STATA version 16.

Result

Twenty four studies with 14,755 patients were included in the meta-analysis. The meta-analyses found that sST2 was significantly associated with the risk of occurrence [HR:1.04, 95% CI: 1.02-1.07, P < 0.01; I2 = 67.8%], recurrence [HR:1.09, 95% CI: 1.02-1.16, P < 0.01; I2 = 89.5%], and MACEs (HR:1.60, 95% CI: 1.13-2.27, P < 0.01; I2 = 82.0%) of AF. Furthermore, patients with AF showed higher sST2 than controls without AF (SMD: 0.41, 95% CI: 0.27-0.54, P < 0.01; I2 = 0%), and AF patients with recurrence after catheter ablation (CA) showed significantly higher sST2 than those without recurrence (SMD: 0.81, 95% CI: 0.33-1.28, P < 0.01; I2 = 83.9%). Sensitivity analyses showed that the outcomes were stable.

Conclusions

Higher sST2 was association with an increased risk of occurrence, recurrence, and MACEs of AF. Assessing sST2 can be used as a potential screening method to predict AF outcomes.

Systematic Review Registration

PROSPERO (CRD42023459789).

Generalized anxiety is a predictor of impaired quality of life in patients with atrial fibrillation: Findings from the prospective observational ARENA study

OBJECTIVE

Atrial fibrillation (AF) is associated with impaired health-related quality of life (HRQoL), an increased risk of morbidity, and mortality. Traditional AF-related outcomes (e.g., AF recurrence) primarily demonstrate the physiological benefits of AF management but do not focus on the benefits experienced subjectively by the patient (i.e., patient-reported outcomes), which have been suggested as optimal endpoints in AF intervention studies. The aim of this study is to identify medical and psychological factors associated with impaired HRQoL at 1-year follow-up.

METHODS

Using data from the prospective observational multicenter ARENA study in patients with AF, we analyzed associations between medical factors, anxiety, and HRQoL at 1-year follow-up assessed using 5-level EuroQoL-5D.

RESULTS

In 1353 AF patients (mean age 71.4 ± 10.3 years, 33.8% female), none of the medical predictors (e.g., heart disease) or history of cardioversion were associated with HRQoL at the 1-year follow-up. Higher generalized anxiety (β = -0.114, p < .001) but not cardiac anxiety (β = -0.006, p = .809) at baseline predicted decreased HRQoL, independent of confounding variables and patients' medical status. Furthermore, the worsening of patients' generalized anxiety was associated with decreased HRQoL (ß = -0.091, p < .001). In contrast, the improvement of generalized anxiety over time predicted higher HRQoL (ß = 0.097, p < .001). Finally, the worsening of patients' cardiac anxiety over time was associated with decreased HRQoL (ß = -0.081, p < .001).

CONCLUSION

Our results highlight the importance of anxiety as a predictor of future HRQoL in patients with AF. Additional studies to examine the impact of anxiety treatment on HRQoL in this population are needed.

CLINICAL TRIAL REGISTRATION

The investigators registered on ClinicalTrials.gov (NCT02978248) on November 30, 2016 https://clinicaltrials.gov/ct2/show/NCT02978248.

TRPV2 inhibitor tranilast prevents atrial fibrillation in rat models of pulmonary hypertension

Atrial fibrillation (AF) is common in pulmonary hypertension (PH), whereas the mechanisms and treatments remain to be explored. TRPV2 regulates the structure and function of the cardiovascular system; however, little attention has been given to its role in AF. This study was to determine whether TRPV2 was involved in PH-induced AF and the effects of TRPV2 inhibitor tranilast on AF in rat models of PH. Monocrotaline (MCT) and SU5416/hypoxia (SuHx)-induced PH models were performed to detect atrial electrophysiological parameters. Daily tranilast (a TRPV2 inhibitor) or saline was given starting 1 day before PH establishment. PH increased the susceptibility to AF, with TRPV2 up-regulated in the right atria. Compared to PH rats, tranilast reduced AF inducibility and the prolongations of ERP and APD; mitigated cardiopulmonary remodeling and the increases in P-wave duration and P-R interval; partially reversed the down-regulation of ion channels such as Cav1.2, Nav1.5, Kv4.3, Kv4.2, Kv1.5, Kir2.1, Kir3.1, Kir3.4 as well as connexin (Cx) 40 and Cx43; improved right atrial (RA) fibrosis, enlargement, and myocardial hypertrophy; decreased the accumulation of inflammatory cells; down-regulated inflammatory indicators such as TNF-α, IL-1β, CXCL1, and CXCL2; and inhibited the activation of the PI3K-AKT-NF-κB signaling pathway. Our results reveal that TRPV2 participates in PH-induced AF, and TRPV2 inhibitor tranilast prevents PH-induced RA remodeling. TRPV2 might be a promising target for PH-induced AF.

Knowledge, attitude and practice toward oral anticoagulants among patients with atrial fibrillation

Background

Atrial fibrillation (AF) is a common cardiac arrhythmia that increases the risk of stroke and other cardiovascular complications. Oral anticoagulants (OACs) are effective in reducing this risk. To investigate the knowledge, attitude and practice (KAP) toward OACs among patients with AF.

Methods

This web-based cross-sectional study was conducted at local Hospital between April 2023 and May 2023, and enrolled AF patients.

Results

A total of 491 valid questionnaires were collected, with 293 (59.67%) male and 73.93% resided in urban areas. The KAP scores were 4.64 ± 3.28, 21.09 ± 2.33 and 26.18 ± 2.15, respectively. Multivariate logistic regression analysis showed that junior high school [odd ratio (OR) = 0.346, 95% confidence interval (CI) = 0.145-0.825, P = 0.017], junior college/bachelor and above (OR = 6.545, 95% CI = 2.863-14.963, P < 0.001), monthly income ≥5,000 (OR = 2.343, 95% CI = 1.074-5.111, P = 0.032), never taken OACs (OR = 0.015, 95% CI = 0.004-0.059, P < 0.001), and having been diagnosed AF (6-10 months, OR = 4.003, 95% CI = 1.653-9.692, P = 0.002;over 20 months, OR = 4.046, 95% CI = 1.753-9.340, P = 0.001) were independently associated with knowledge. Knowledge (OR = 1.376, 95% CI = 1.162-1.629, P < 0.001), junior high school (OR = 0.258, 95% CI = 0.084-0.792, P = 0.018), monthly income ≥5,000 (OR = 5.486, 95% CI = 1.834-16.412, P = 0.002), and never undergone AF ablation (OR = 0.214, 95% CI = 0.097-0.471, P < 0.001) were independently associated with attitude. Knowledge (OR = 1.128, 95% CI = 1.030-1.235, P = 0.009), 70-79 years (OR = 2.193, 95% CI = 1.166-4.124, P = 0.015) and ≥80 years (OR = 4.375, 95% CI = 2.034-9.411, P < 0.001) were independently associated with proactive practice.

Conclusion

Patients with AF had inadequate knowledge, suboptimal attitude and inactive practice towards AF and OACs. Improving patient education, especially among those with lower education levels, enhances understanding and management of AF and OACs.

A Predictive Model of New-Onset Atrial Fibrillation After Percutaneous Coronary Intervention in Acute Myocardial Infarction Based on the Lymphocyte to C-Reactive Protein Ratio

Purpose

Lymphocyte to C-reactive protein ratio (LCR) is a recognized systemic inflammatory marker and novel prognostic indicator for several cancers. This study investigated the relationship between preoperative LCR and new-onset atrial fibrillation (NOAF) in patients with acute myocardial infarction (AMI) after percutaneous coronary intervention (PCI).

Patients and Methods

Patients with AMI (n=662) with no history of atrial fibrillation (AF) were enrolled and classified into NOAF and non-NOAF groups based on the occurrence of postoperative NOAF during hospitalization. Logistic regression models were used to analyze NOAF risk factors and to assess the association between preoperative LCR and NOAF incidence. We constructed a new nomogram from the selected NOAF risk factors, and tested its predictive performance, degree of calibration, and clinical utility using receiver operating characteristic and calibration curves, decision curve analysis, and clinical impact curves.

Results

Overall, 84 (12.7%) patients developed NOAF during hospitalization. The LCR was significantly lower in the NOAF group. Preoperative LCR accurately predicted NOAF after AMI and was correlated with increased NOAF risk. Age, body mass index, diabetes, serum albumin levels, uric acid levels, left atrium (LA) diameter, left ventricular ejection fraction, left circumflex artery stenosis > 50%, and Killip class II status were independent predictors of NOAF after AMI. In addition, a new nomogram combined with LCR was constructed to stratify the risk of NOAF in patients with AMI. The performance of the new nomogram was satisfactory, as shown by the receiver operating characteristic curve, calibration curve, decision curve analysis and clinical impact curve.

Conclusion

Preoperative LCR was an independent predictor of NOAF in patients with AMI after PCI. The novel nomogram combined with LCR could rapidly and individually identify and treat patients at a high risk of NOAF.

Impact of low-dose Brain-Derived Neurotrophic Factor (BDNF) on atrial fibrillation recurrence

BACKGROUND

Atrial fibrillation is the most common arrhythmia worldwide and is associated with significant morbidity and mortality. Despite the effectiveness of catheter-based ablation, periprocedural complication and recurrences remain a concern. In this context, we aim to appraise the potential impact of brain-derived neurotrophic factor (BDNF) on reducing episodes of paroxysmal atrial fibrillation (PAF).

METHODS

22 patients with an established diagnosis of PAF and without structural heart disease were considered. Every patient received 20 drops of GUNA-BDNF administered in the morning. During the 24 months of follow-up, the arrhythmic burden was measured by the average monthly duration of PAF episodes.

RESULTS

At the end of the follow-up period (24 months), data from 22 patients, of whom 17 men and five women, were analyzed. The arrhythmic burden, measured in terms of average monthly duration of PAF episodes, was found significantly reduced after the administration of low dose BDNF (9.5 vs. 65.3 minutes per month, P<0.001). A total of 17 out of 22 patients saw their arrhythmic burden eliminated or consistently reduced, furthermore two patients underwent a drastic reduction of the average monthly duration of AF (more than 200 minutes compared to the baseline). Only four patients, despite the administration of BDNF, still experienced an arrhythmic burden of 20 minutes or more. Considering the age groups, the major reduction was observed in people aged 70 or more, who were also the most represented in the sample. These results are coherent with the poor literature currently available.

CONCLUSIONS

BDNF low dose therapy has shown to have an impacting role in reducing the arrhythmic burden and recurrences of AF, with a particular effectiveness in patients over 70 and without structural heart disease. We should welcome this work, despite it limitations. Further clinical and molecular studies are needed before-considering BDNF low dose as a tool against PAF.

The HF-AF ENERGY Trial: Nicotinamide Riboside for the Treatment of Atrial Fibrillation in Heart Failure Patients

BACKGROUND

The presence of atrial fibrillation (AF) in heart failure (HF) patients with reduced ejection fraction is common and associated with an increased risk of stroke, hospitalization and mortality. Recent research findings indicate that a reduction in nicotinamide adenine dinucleotide (NAD+) levels results in mitochondrial dysfunction, DNA damage and consequently cardiomyocyte impairment in experimental and clinical HF and AF. The HF-AF ENERGY trial aims to investigate the cardioprotective effects of the NAD+ precursor nicotinamide riboside (NR) treatment in ischemic heart disease patients diagnosed with AF.

STUDY DESIGN

The HF-AF ENERGY trial is a prospective intervention study. The study consists of a (retrospective) 4 months observation period and a 4 months intervention period. The cardioprotective effect of NR on AF burden is investigated by remote monitoring software of implantable cardiac defibrillators (ICDs), which enables continuous atrial rhythm monitoring detection. Cardiac dimension and function are examined by echocardiography. Laboratory blood analysis is performed to determine mitochondrial function markers and energy metabolism. All the study parameters are assessed at two fixed time points (pre- and post-treatment). Pre- and post-treatment outcomes are compared to determine the effects of NR treatment on AF burden, mitochondrial function markers and energy metabolism.

CONCLUSION

The HF-AF ENERGY trial investigates the cardioprotective effects of NR on AF burden and whether NR normalizes blood-based mitochondrial function markers and energy metabolites of the NAD metabolome in ischemic heart disease patients diagnosed with AF. The study outcomes elucidate whether NAD+ metabolism can be used as a future therapy for HF patients with AF.