Associations of Epicardial, Abdominal, and Overall Adiposity With Atrial Fibrillation

Association of adipose tissue infiltration with cardiac function: scoping review

Evidence suggests that adipose tissue (AT) infiltration in skeletal muscles may negatively influence cardiac function, yet its use as a biomarker remains unclear. This scoping review examined the relationship between AT infiltration and cardiac function in adults. A systematic search of PubMed, CINAHL and SCOPUS identified peer-reviewed studies reporting AT infiltration and cardiac function measures. Excluded were review-type studies, animal studies, abstracts and case series. Study quality was assessed using the Study Quality Assessment Tool (SQAT). Three good-quality studies were included. Findings demonstrated a negative association between AT infiltration and cardiac function parameters, including exercise capacity, left ventricular ejection fraction (LVEF) and heart failure events, in cancer survivors and healthy individuals. There is evidence supporting an association between increased AT infiltration of skeletal muscles and impaired cardiac function, highlighting the need for further research to validate AT infiltration as a potential biomarker. Despite the limited available studies, our findings highlight a distinct association between skeletal muscle AT infiltration and cardiac dysfunction, independent of general obesity.

Bridging the gap in obesity research: A consensus statement from the European Society for Clinical Investigation

BACKGROUND

Most forms of obesity are associated with chronic diseases that remain a global public health challenge.

AIMS

Despite significant advancements in understanding its pathophysiology, effective management of obesity is hindered by the persistence of knowledge gaps in epidemiology, phenotypic heterogeneity and policy implementation.

MATERIALS AND METHODS

This consensus statement by the European Society for Clinical Investigation identifies eight critical areas requiring urgent attention. Key gaps include insufficient long-term data on obesity trends, the inadequacy of body mass index (BMI) as a sole diagnostic measure, and insufficient recognition of phenotypic diversity in obesity-related cardiometabolic risks. Moreover, the socio-economic drivers of obesity and its transition across phenotypes remain poorly understood.

RESULTS

The syndemic nature of obesity, exacerbated by globalization and environmental changes, necessitates a holistic approach integrating global frameworks and community-level interventions. This statement advocates for leveraging emerging technologies, such as artificial intelligence, to refine predictive models and address phenotypic variability. It underscores the importance of collaborative efforts among scientists, policymakers, and stakeholders to create tailored interventions and enduring policies.

DISCUSSION

The consensus highlights the need for harmonizing anthropometric and biochemical markers, fostering inclusive public health narratives and combating stigma associated with obesity. By addressing these gaps, this initiative aims to advance research, improve prevention strategies and optimize care delivery for people living with obesity.

CONCLUSION

This collaborative effort marks a decisive step towards mitigating the obesity epidemic and its profound impact on global health systems. Ultimately, obesity should be considered as being largely the consequence of a socio-economic model not compatible with optimal human health.

Postoperative atrial fibrillation following cardiac surgery in severe obesity: the added value of waist circumference

INTRODUCTION

Obesity is an independent risk factor for postoperative atrial fibrillation (POAF) after coronary artery bypass grafting (CABG) surgery. POAF in patients with severe obesity (body mass index [BMI] ≥ 35 kg/m2) is less studied. Whether waist circumference (WC) improves prediction of POAF independently of BMI among patients with severe obesity remains unknown.

AIM

To evaluate the risk of POAF, the role of WC in predicting POAF and postoperative complications after CABG surgery in severe obesity.

METHODS

Our cohort included 7995 patients undergoing CABG surgery (2006-19). POAF risk was compared across BMI and WC categories. In patients with severe obesity, the association of an increase in WC with POAF risk was assessed.

RESULTS

763 (9.5%) patients had a BMI ≥ 35 kg/m2. In this group, BMI was 38.5 ± 3.6 kg/m2 and WC was 123.4 ± 10.8 cm. More patients with severe obesity developed POAF compared to patients with a normal BMI (37 vs. 29%, aRR: 1.52[95%CI 1.36-1.72], p < 0.01). Within each BMI category, the risk of POAF was higher per increasing tertile of WC (p < 0.05). Among patients with a BMI ≥ 35 kg/m2, every 10 cm increment in WC was associated with an increased risk of POAF (aRR: 1.16[95%CI 1.08-1.24], p < 0.01). POAF in patients with severe obesity was associated with increased hospital length of stay.

CONCLUSIONS

Severe obesity increases the risk of POAF after CABG surgery. In this subgroup, elevated WC may provide additional prognostic value independently of BMI. Since POAF is associated with adverse long-term outcomes, abdominal obesity by measurement of WC should be assessed and targeted even in patient with severe obesity. Central Illustration Increasing waist circumference associated with increased atrial fibrillation risk post coronary artery bypass grafting. Bar graph of the unadjusted absolute risk and 95% confidence interval of postoperative atrial fibrillation for each tertile of waist circumference per body mass index category. Comparison of postoperative atrial fibrillation risk with chi-square test showing an increasing risk of postoperative atrial fibrillation related to increasing waist circumference within each body mass index category.

ABBREVIATIONS

BMI, body mass index; POAF, postoperative atrial fibrillation; WC, waist circumference.

Association between surrogate insulin resistance markers and postablation atrial fibrillation recurrence: A systematic review and meta-analysis

Atrial fibrillation (AF) is the most common persistent arrhythmia and demonstrates a notable recurrence rate after ablation. Previous studies have suggested that surrogate markers of insulin resistance could predict postablation AF recurrence. This systematic review and meta-analysis aimed to assess studies examining the relationship between surrogate insulin resistance markers and the recurrence of AF after ablation. We searched PubMed, Web of Science, Embase, and Scopus for observational studies published from inception to August 2024. We incorporated studies that assessed the relationship between surrogate insulin resistance markers and the occurrence of postablation AF in patients with either paroxysmal or persistent AF. The random-effects model was used for meta-analysis. The Newcastle-Ottawa scale was used to evaluate risk of bias, and the leave-one-out method was applied for sensitivity analysis (PROSPERO: CRD42024584526). Nine studies involving 7729 participants met the inclusion criteria. Significant associations with AF recurrence were observed for the triglyceride-glucose index (hazard ratio [HR] 1.29; 95% confidence interval [CI] 1.15-1.44; I2 = 44%), homeostatic model assessment of insulin resistance (HR 1.27; 95% CI 1.14-1.42; I2 = 0%), and metabolic score for insulin resistance (HR 1.04; 95% CI 1.03-1.05; I2 = 0%). However, the triglyceride-to-high-density lipoprotein ratio did not demonstrate a statistically significant association with AF recurrence (HR 1.09; 95% CI 0.96-1.24; I2 = 86%). Surrogate markers of insulin resistance can be valuable predictors for assessing the risk of AF recurrence in patients who have undergone catheter ablation, potentially aiding in preventive strategies. Nevertheless, further prospective studies are required to validate our findings.

Relationship between epicardial adipose tissue volume and atrial fibrillation in patients with rheumatoid arthritis

Introduction

Epicardial adipose tissue (EAT) is involved in cardiac inflammatory responses and has been associated with both atrial fibrillation (AF) and rheumatoid arthritis (RA). However, the condition of EAT in patients with both RA and AF is still unclear. In addition, the risks of stroke and bleeding in patients with both RA and AF are unknown.

Methods

A retrospective analysis was conducted in patients with RA aged ≥18 years from August 2021 to May 2023, and compared with age- and gender-matched patients without RA. The volume of EAT was measured using chest computed tomography and the EAT/body mass index (BMI) ratio was used to correct for the possible impact of BMI differences. The stroke and bleeding risks of the patients were assessed using the CHA2DS2-VASc or HAS-BLED scores.

Results

A total of 145 patients with RA and 282 patients without RA were included. The volume of EAT or EAT/BMI ratio was similar between the patients with RA and no AF and those without both RA and AF. Compared to the patients without AF, those with AF had a larger EAT volume or EAT/BMI ratio, regardless of whether they had RA or not. EAT/BMI ratio was significantly associated with left atrial (LA) diameter among the patients with RA (RR = 2.23, P < 0.001) but not among the patients without RA (P < 0.954). The RA groups had larger LA-EAT volume (31.53 ± 11.02 mm3 vs. 22.56 ± 9.58 mm3, p < 0.001) and LA-EAT/Total EAT ratio (23.02% ± 3.62% vs. 18.74 ± 3.38 mm3, p < 0.001) than that in non-RA groups. In addition, the proportion of patients with high stroke risk scores was higher among the patients with both RA and AF compared to those without RA but with AF (90.90% vs. 72.00% in men; 84.78% vs. 71.11% in women), while the proportion of patients with high bleeding risk scores was lower (22.06% vs. 27.85%).

Conclusion

LA diameter correlates with the EAT/BMI ratio in patients with RA who exhibit larger LA-EAT volume and LA-EAT/total EAT ratios compared to individuals without RA.

Epicardial Fat in Heart Failure and Preserved Ejection Fraction: Novel Insights and Future Perspectives

PURPOSE OF REVIEW

Cardiovascular effects of obesity may be driven, in part, by the distribution of fat. More recently, epicardial adipose tissue (EAT) has gained recognition as an adverse visceral fat impacting cardiac dysfunction in heart failure with preserved ejection fraction (HFpEF).

RECENT FINDINGS

EAT can be identified and measured using several non-invasive imaging techniques, including transthoracic echocardiography, computed tomography, and cardiac magnetic resonance. The presence of EAT is associated with increased risk of HFpEF and worse clinical outcomes among patients with established HFpEF, independent of total adiposity. EAT may serve a pivotal role in the pathogenesis of HFpEF by worsening volume distribution, enhancing pericardial restraint and ventricular interaction, worsening right ventricular dysfunction, and diminishing exercise tolerance. No large trials have tested the effects of reducing fat in specific areas of the body on cardiovascular outcomes, but some studies that followed people in communities and trials over time have suggested that drug and non-drug treatments that lower EAT could improve the risk factors for heart problems in patients with HFpEF. Further understanding the role that pathogenic fat depots play in HFpEF incidence and progression may provide future therapeutic targets in treating the obese-HFpEF phenotype.

Synergistic Effect of the CHA2DS2-VASc Score and Left Atrial Epicardial Adipose Tissue Volume on Predicting Atrial Fibrillation Recurrence After Ablation

Objective

The CHA2DS2-VASc score and left atrial epicardial adipose tissue (LA-EAT) volume have been identified as potential risk factors for atrial fibrillation (AF) recurrence after ablation. However, there is currently a lack of research specifically examining the interaction between these two AF risk factors. This study aims to evaluate the predictive potential of combining CHA2DS2-VASc score and LA-EAT volume in predicting recurrence in patients with AF who undergo ablation.

Methods

The study encompassed a cohort of 507 patients who underwent ablation for AF finally. Follow-up assessments were conducted 1, 3, 6, and 12 months after ablation, including clinical evaluation, a 12-lead ECG, and 24-hour Holter monitoring. Recurrence was characterized by symptomatic or asymptomatic AF episodes or atrial tachycardia lasting more than 30 seconds, as evidenced by any ECG following the 3-month BP. Patients were stratified into groups based on the defined cut-off values of CHA2DS2-VASc score and LA-EAT volume. Cox regression analysis was employed to estimate the risk factor of AF recurrence after ablation. The interaction between CHA2DS2-VASc score and LA-EAT volume was assessed using the relative excess risk due to interaction (RERI), attributable proportion (AP), and synergy index (SI).

Results

140 patients experienced AF recurrence after ablation during the follow-up period. Multivariable Cox regression analysis demonstrated that CHA2DS2-VASc score and LA-EAT volume were independent risk factors for AF recurrence. Patients with higher CHA2DS2-VASc score and LA-EAT volume exhibited a higher risk of recurrence than those with lower score and volume. Furthermore, a significant synergistic interaction existed between CHA2DS2-VASc score and LA-EAT volume. The LA-EAT volume and clinical model combination improved the predictive value reclassification, and discriminant abilities improved significantly.

Conclusion

There is a significant additive interaction between CHA2DS2-VASc score and LA-EAT volume, with the coexistence of both factors significantly increasing the risk of AF recurrence after ablation.

The role of multi-modality imaging for the assessment of left atrium and left atrial appendage: a clinical consensus statement of the European Association of Cardiovascular Imaging (EACVI), European Heart Rhythm Association (EHRA) of the European Society of Cardiology (ESC)

Structural, architectural, contractile, or electrophysiological alterations may occur in the left atrium (LA). The concept of LA cardiopathy is supported by accumulating scientific evidence demonstrating that LA remodelling has become a cornerstone diagnostic and prognostic marker. The structure and the function of the LA and left atrial appendage (LAA), which is an integral part of the LA, are key elements for a better understanding of multiple clinical conditions, most notably atrial fibrillation, cardioembolism, heart failure, and mitral valve diseases. Rational use of various imaging modalities is key to obtain the relevant clinical information. Accordingly, this clinical consensus document from the European Association of Cardiovascular Imaging, in collaboration with the European Heart Rhythm Association, provides comprehensive, up-to-date, and evidence-based guidance to cardiologists and cardiac imagers for the best practice of imaging LA and LAA for the diagnosis, management, and prognostication of the patients.

Targeting Epicardial/Pericardial Adipose Tissue in Cardiovascular Diseases: A Novel Therapeutic Strategy

Cardiovascular diseases (CVDs) remain a global health concern, prompting ongoing research into novel contributors to their pathogenesis. Due to the proximity of the coronary arteries and the myocardium in epicardial adipose tissue (EAT) and pericardial adipose tissue (PAT), these tissues have emerged as key areas of interest for their potential influence on cardiac function and vascular health. This review synthesizes current research on the physiological and biological characteristics of EAT and PAT, exploring their composition and clinical measurement approaches. The roles of EAT and PAT in coronary artery disease (CAD), atrial fibrillation, and heart failure are discussed, and the contributions of EAT and PAT to these cardiovascular conditions are highlighted alongside their potential as therapeutic targets.

Comprehensive assessment of distinct abdominal fat compartments beyond liver content in overweight/obese patients using MRI and ultrasound imaging

BACKGROUND

Ectopic fat deposition, involving lipid infiltration within organs and fat accumulating surrounding organs, plays a crucial role in the development of metabolic abnormalities in obesity. Current imaging measurements of obesity primarily focus on lipid infiltration within liver, neglecting fat deposition in other areas. This study aims to explore the methods of measuring and correlating different types of abdominal ectopic fat deposition in obese patients using magnetic resonance imaging (MRI) and ultrasound techniques, and to investigate the relationship between these fat parameters and obesity-related metabolic markers.

METHODS

Abdominal ectopic fat deposition including liver fat content, mesenteric fat thickness (MFT), perirenal fat thickness (PrFT) and preperitoneal fat thickness (PFT) were measured in 220 overweight/obese patients using both MRI and ultrasound techniques. Correlation analysis validated the concordance of fat parameters at specific sites between the two imaging methods and identified the cutoff values of hepatic attenuation coefficient (AC) for diagnosis of liver steatosis. Additionally, we investigated the correlation between fat parameters by both methods and obesity-related metabolic markers.

RESULTS

Ultrasonic measurement of PrFT and hepatic AC both had high correlation with PrFT (r = 0.829, p < 0.001) and hepatic Proton-density fat fraction (PDFF, r = 0.822, p < 0.001) measured via MR. Hepatic AC cutoff values for diagnosing mild, moderate, and severe fatty liver were 0.705 dB/cm/MHz (AUC = 0.922), 0.755 dB/cm/MHz (AUC = 0.923), and 0.875 dB/cm/MHz (AUC = 0.890) respectively. Hepatic AC correlated significantly with AST and ALT (r = 0.477 ~ 0.533, p < 0.001). MFT measured by ultrasound were positively associated with glycated hemoglobin (r = 0.324 ~ 0.371, p < 0.001) and serum triglyceride levels (r = 0.303 ~ 0.353, p < 0.001). PrFT measured by both methods showed significant positive correlations with serum creatinine levels (r = 0.305 ~ 0.308, p < 0.001).

CONCLUSIONS

Both MRI and ultrasound demonstrate metabolic correlations in quantifying mesenteric, hepatic, and perirenal fat. In addition to assessment of liver fat content, the measurements of ectopic fat deposition by MRI or ultrasound are a simple and crucial way for comprehensive fat evaluation in individuals with overweight/obesity.

The Close Link Between Obesity and Cardiovascular Disease: Current Insights and Remaining Challenges

Obesity is a global public health crisis, contributing to chronic disease development and poor prognosis. A large body of evidence consistently demonstrates that increased adiposity leads to many cardiovascular diseases (CVDs) and complications, such as coronary artery disease, heart failure, and arrhythmias, via direct and indirect mechanisms. Therefore, weight management is crucial to reduce and prevent cardiovascular risk. The recent emergence of glucose-like peptide-1 receptor agonists shows remarkable weight reduction and cardiovascular prevention. Despite the clear benefits, controversies and challenges on obesity-related CVD remain. This review aims to provide a comprehensive understanding of obesity-related CVD and explore current remaining tasks.

Predicting Atrial Fibrillation Relapse Using Bayesian Networks: Explainable AI Approach

Background

Atrial fibrillation (AF) is a prevalent arrhythmia associated with significant morbidity and mortality. Despite advancements in ablation techniques, predicting recurrence of AF remains a challenge, necessitating reliable models to identify patients at risk of relapse. Traditional scoring systems often lack applicability in diverse clinical settings and may not incorporate the latest evidence-based factors influencing AF outcomes. This study aims to develop an explainable artificial intelligence model using Bayesian networks to predict AF relapse postablation, leveraging on easily obtainable clinical variables.

Objective

This study aims to investigate the effectiveness of Bayesian networks as a predictive tool for AF relapse following a percutaneous pulmonary vein isolation (PVI) procedure. The objectives include evaluating the model's performance using various clinical predictors, assessing its adaptability to incorporate new risk factors, and determining its potential to enhance clinical decision-making in the management of AF.

Methods

This study analyzed data from 480 patients with symptomatic drug-refractory AF who underwent percutaneous PVI. To predict AF relapse following the procedure, an explainable artificial intelligence model based on Bayesian networks was developed. The model used a variable number of clinical predictors, including age, sex, smoking status, preablation AF type, left atrial volume, epicardial fat, obstructive sleep apnea, and BMI. The predictive performance of the model was evaluated using the area under the receiver operating characteristic curve (AUC-ROC) metrics across different configurations of predictors (5, 6, and 7 variables). Validation was conducted through four distinct sampling techniques to ensure robustness and reliability of the predictions.

Results

The Bayesian network model demonstrated promising predictive performance for AF relapse. Using 5 predictors (age, sex, smoking, preablation AF type, and obstructive sleep apnea), the model achieved an AUC-ROC of 0.661 (95% CI 0.603-0.718). Incorporating additional predictors improved performance, with a 6-predictor model (adding BMI) achieving an AUC-ROC of 0.703 (95% CI 0.652-0.753) and a 7-predictor model (adding left atrial volume and epicardial fat) achieving an AUC-ROC of 0.752 (95% CI 0.701-0.800). These results indicate that the model can effectively estimate the risk of AF relapse using readily available clinical variables. Notably, the model maintained acceptable diagnostic accuracy even in scenarios where some predictive features were missing, highlighting its adaptability and potential use in real-world clinical settings.

Conclusions

The developed Bayesian network model provides a reliable and interpretable tool for predicting AF relapse in patients undergoing percutaneous PVI. By using easily accessible clinical variables, presenting acceptable diagnostic accuracy, and showing adaptability to incorporate new medical knowledge over time, the model demonstrates a flexibility and robustness that makes it suitable for real-world clinical scenarios.

The Role of Early Risk Factor Modification and Ablation in Atrial Fibrillation Substrate Remodeling Prevention

Atrial fibrillation (AF) is the most common sustained arrhythmia, contributing to significant morbidity and healthcare burden worldwide. This review evaluates the role of early risk factor modification and timely catheter ablation in preventing AF progression and improving patient outcomes. A comprehensive literature search was conducted using PubMed, MEDLINE, and Google Scholar, focusing on studies published after the ESC 2020 guidelines for the diagnosis and management of AF up to the release of the updated ESC 2024 guidelines for the management of AF. Keywords included "atrial fibrillation", "catheter ablation", "risk factor management", and "psychological stress". Relevant clinical trials, randomized controlled trials, systematic reviews, and meta-analyses were included, with particular emphasis on novel studies contributing to the ESC 2024 updated recommendations. Traditional risk factors such as obesity, hypertension, diabetes, sleep apnea, alcohol consumption, and physical exertion are well established in AF progression. Early evidence also suggests a role for psychological stress and mood disorders, including depression and post-traumatic stress disorder (PTSD), in increasing AF susceptibility. Psychological stress and mood disorders are linked to AF primarily through behavioral changes such as poor medication adherence, unhealthy lifestyle choices, and increased substance use. Recent guidelines recommend early catheter ablation in selected patients to reduce AF burden, prevent atrial remodeling, and improve quality of life, particularly in those resistant to antiarrhythmic drugs or individuals with AF-induced cardiomyopathy. Furthermore, we highlight the importance of a patient-centered, multidisciplinary approach, integrating electrophysiologists, cardiologists, and primary care providers with structured risk factor interventions and shared decision-making. Despite these advances, gaps remain in defining optimal timing, patient selection, and long-term benefits of catheter ablation in persistent AF, necessitating the need for further research. By integrating early intervention, personalized treatment strategies, and collaborative care models, we may usher in a paradigm shift in AF management, improving long-term cardiovascular outcomes and patient quality of life.

Impact of risk factors on atrial fibrillation types via epicardial adipose tissue computed tomography-based radiomics analysis

AIM

To analyze epicardial adipose tissue (EAT) radiomics and assess the impact of risk factors on different types of atrial fibrillation (AF).

MATERIALS AND METHODS

We included AF patients undergoing radiofrequency ablation from June 2018 to December 2020. Propensity score matching (PSM) was employed to limit the differences in risk factors between patients with different types of AF. The nnU-Net model was utilized to segment EAT. After extracting radiomic features, a generalized linear model was used to examine the epicardial adipose tissue (EAT) radiomic features associated with risk factors, and logistic regression analysis was conducted to identify the features differentiating the two AF groups. Hierarchical clustering was utilized to identify clusters among significant features.

RESULTS

After PSM, 794 patients (median age 67, 547 males) were selected, with 397 having paroxysmal and 397 persistent AF. In univariate analysis, 15.11% of the features were significantly associated with the type of AF (P<.000005). 39.29% of all features were significantly correlated with at least one risk factor, with 141 features being significantly related to both risk factors and the type of AF. Three independent clusters were successfully identified among the 141 features. The biggest cluster is dominated by hypertension and hyperlipidemia factors, exhibiting a high overlap in their effects on EAT. Following closely in influence are gender, age, and diabetes clusters, collectively covering 59 out of the 141 features.

CONCLUSION

Our study identifies distinct differences in EAT characteristics between paroxysmal and persistent AF, with persistent cases showing higher EAT gray values and a more disordered texture.

The change of epicardial adipose tissue characteristics and vulnerability for atrial fibrillation upon drastic weight loss

BACKGROUND

Obesity increases the risk of atrial fibrillation (AF). We hypothesize that 'obese' epicardial adipose tissue (EAT) is, regardless of comorbidities, associated with markers of AF vulnerability.

METHODS

Patients >40y of age undergoing bariatric surgery and using <2 antihypertensive drugs and no insulin were prospectively included. Study investigations were conducted before and 1y after surgery. Heart rhythm and p-wave duration were measured through ECGs and 7-d-holters. EAT-volume and attenuation were determined on non-enhanced CT scans. Serum markers were quantified by ELISA.

RESULTS

Thirty-seven patients underwent surgery (age: 52.1 ± 5.9y; 27 women; no AF). Increased p-wave duration correlated with higher BMI, larger EAT volumes, and lower EAT attenuations (p < 0.05). Post-surgery, p-wave duration decreased from 109 ± 11 to 102 ± 11ms. Concurrently, EAT volume decreased from 132 ± 49 to 87 ± 52ml, BMI from 43.2 ± 5.2 to 28.9 ± 4.6kg/m2, and EAT attenuation increased from -76.1 ± 4.0 to -71.7 ± 4.4HU (p <0.001). Adiponectin increased from 8.7 ± 0.8 to 14.2 ± 1.0 μg/ml (p <0.001). However, decreased p-wave durations were not related to changed EAT characteristics, BMI or adiponectin.

CONCLUSION

In this explorative study, longer p-wave durations related to higher BMIs, larger EAT volume, and lower EAT attenuations. P-wave duration and EAT volume decreased, and EAT attenuation increased upon drastic weightloss. However, there was no relation between decreased p-wave duration and changed BMI or EAT characteristics.

Cardio-Lipotoxicity of Epicardial Adipose Tissue

Epicardial adipose tissue is a unique visceral adipose tissue depot that plays a crucial role in myocardial metabolism. Epicardial adipose tissue is a major source of energy and free fatty acids for the adjacent myocardium. However, under pathological conditions, epicardial fat can affect the heart through the excessive and abnormal influx of lipids. The cardio-lipotoxicity of the epicardial adipose tissue is complex and involves different pathways, such as increased inflammation, the infiltration of lipid intermediates such as diacylglycerol and ceramides, mitochondrial dysfunction, and oxidative stress, ultimately leading to cardiomyocyte dysfunction and coronary artery ischemia. These changes can contribute to the pathogenesis of various cardio-metabolic diseases including atrial fibrillation, coronary artery disease, heart failure, and obstructive sleep apnea. Hence, the role of the cardio-lipotoxicity of epicardial fat and its clinical implications are discussed in this review.

Bariatric surgery partially reverses subclinical proarrhythmic structural, electrophysiological, and autonomic changes in obesity

BACKGROUND

Obesity confers higher risks of cardiac arrhythmias. The extent to which weight loss reverses subclinical proarrhythmic adaptations in arrhythmia-free obese individuals is unknown.

OBJECTIVE

The purpose of this study was to study structural, electrophysiological, and autonomic remodeling in arrhythmia-free obese patients and their reversibility with bariatric surgery using electrocardiographic imaging (ECGi).

METHODS

Sixteen arrhythmia-free obese patients (mean age 43 ± 12 years; 13 (81%) female participants; BMI 46.7 ± 5.5 kg/m2) had ECGi pre-bariatric surgery, of whom 12 (75%) had ECGi postsurgery (BMI 36.8 ± 6.5 kg/m2). Sixteen age- and sex-matched lean healthy individuals (mean age 42 ± 11 years; BMI 22.8 ± 2.6 kg/m2) acted as controls and had ECGi only once.

RESULTS

Obesity was associated with structural (increased epicardial fat volumes and left ventricular mass), autonomic (blunted heart rate variability), and electrophysiological (slower atrial conduction and steeper ventricular repolarization time gradients) remodeling. After bariatric surgery, there was partial structural reverse remodeling, with a reduction in epicardial fat volumes (68.7 cm3 vs 64.5 cm3; P = .0010) and left ventricular mass (33 g/m2.7 vs 25 g/m2.7; P < .0005). There was also partial electrophysiological reverse remodeling with a reduction in mean spatial ventricular repolarization gradients (26 mm/ms vs 19 mm/ms; P = .0009), although atrial activation remained prolonged. Heart rate variability, quantified by standard deviation of successive differences in R-R intervals, was also partially improved after bariatric surgery (18.7 ms vs 25.9 ms; P = .017). Computational modeling showed that presurgical obese hearts had a larger window of vulnerability to unidirectional block and had an earlier spiral-wave breakup with more complex reentry patterns than did postsurgery counterparts.

CONCLUSION

Obesity is associated with adverse electrophysiological, structural, and autonomic remodeling that is partially reversed after bariatric surgery. These data have important implications for bariatric surgery weight thresholds and weight loss strategies.

Serum uric acid, body mass index, and cardiovascular diseases: A multiple two-step Mendelian randomization study

BACKGROUND AND AIMS

A number of health issues, including high serum uric acid (SUA) and cardiovascular disease (CVD), have been linked to obesity based on observational evidence, though it's currently unclear how these issues are causally related. In order to determine whether obesity mediates this association, we set out to investigate the causal relationship between SUA, obesity, and CVD.

METHODS AND RESULTS

From publicly available genome-wide association studies, we acquired instrumental variables that had a strong correlation to SUA and body mass index (BMI). We employed multiple two-step Mendelian randomization (MR) analyses, using genetic and clinical data from various publicly available biological databases. The mediating role of BMI was examined through mediation analysis. SUA was genetically correlated with BMI [OR = 1.080, 95% CI: 1.024-1.139, P = 0.005]. There was a positive causal effect of SUA on AF [OR = 0.892, 95% CI: 0.804-0.990, P = 0.032], CAD [OR = 0.942, 95% CI: 0.890-0.997, P = 0.037], and EHT [OR = 1.080, 95% CI: 1.024-1.139, P = 0.005]. Among them, BMI mediated the effects of SUA on AF (42.2%; 95% CI, 35.3%-51.9%), CAD (76.3%; 95% CI, 63.4%-92.0%), and EHT (10.0%; 95% CI, 0%-20.0%).

CONCLUSION

Our research revealed a causal relationship between high SUA exposure and an increased risk of obesity. Additionally, a high SUA level was linked to an increased risk of various CVDs. Given that individuals with high SUA are more likely to be susceptible to AF, CAD, and EHT, attention must be given to their weight status.

Sex-Specific Cardiometabolic Determinants of Postoperative Atrial Fibrillation After Cardiac Surgery

BACKGROUND

Cardiometabolic diseases increase the risk of postoperative atrial fibrillation (POAF), a complication leading to higher long-term risk of major cardiovascular events (MACE). It remains unknown whether the effect of these risk factors differs according to sex. We sought to evaluate the sex-specific predictors of POAF after coronary artery bypass grafting (CABG).

METHODS

In a prospective registry of patients undergoing isolated CABG, we compared predictors of POAF between sexes with logistic regression models. Because of high prevalence of abdominal obesity in women, > 80% having a waist circumference (WC) ≥ 88 cm, median WC values were used to define abdominal obesity (men ≥ 102 cm, women ≥ 100 cm).

RESULTS

This analysis included 6177 individuals (17% women). Mean age was 65.6 ± 8.9 years. POAF occurred in 32% of men and 28% of women (P < 0.05). Compared with men, women with POAF had similar WC; higher prevalence of hypertension and diabetes; lower high-density lipoprotein (HDL)-cholesterol; and higher glucose, triglyceride, low- density lipoprotein (LDL)-cholesterol, and C-reactive protein levels (all P < 0.05). After adjustment, age and abdominal obesity were associated with POAF in both sexes (P < 0.05). The interaction of WC with sex suggested a worse impact of WC on POAF risk among women (adjusted odds ratio [OR], 1.97; 95% confidence interval [CI], 1.48-2.62 vs in men 1.33; 95% CI, 1.17-1.50; P for interaction = 0.01).

CONCLUSIONS

Abdominal obesity is a major predictor of POAF in both sexes, with higher risk in women. These results emphasize the need for enhanced strategies to manage abdominal obesity and its cardiometabolic consequences in the general population and the potential to develop sex-specific preventive interventions to reduce risk of POAF.

Risk Factor Management for Patients with Atrial Fibrillation in Home Healthcare

Atrial fibrillation (AF) is a common and persistent cardiac arrhythmia that impacts morbidity, mortality, disability, quality of life, and healthcare costs. Typically, AF is managed using a three-pillar approach of rate control, rhythm control, and anticoagulation. However, these interventions fail to address the underlying pathophysiological factors that contribute to AF. A compelling body of research expands traditional management by focusing on lifestyle modification to lower the risk of AF incidence, prevalence, progression, and severity. Home healthcare clinicians possess the knowledge and skills to examine and treat a wide range of risk factors that lead to AF, and therefore can substantially reduce incident and persistent AF and facilitate optimal outcomes. This perspective paper presents a clinical paradigm shift by proposing a five-factor Partner, Quantify, Recommend, Support, and Teach (PQRST) framework to support AF risk factor modification in home healthcare. The PQRST framework incorporates a greater focus on patient self-management through education and exercise to reduce incidence, prevalence, progression, and severity of AF.

Determinants of echocardiographic epicardial adipose tissue in a general middle-aged population - The Cardiovascular Risk in Young Finns Study

Epicardial adipose tissue (EAT) is the cardiac visceral fat depot proposed to play a role in the etiology of various cardiovascular disease outcomes. Little is known about EAT determinants in a general population. We examined cardiometabolic, dietary, lifestyle and socioeconomic determinants of echocardiograpghically measured EAT in early adulthood. Data on cardiometabolic, dietary, lifestyle and socioeconomic factors were collected from participants of the Cardiovascular Risk in Young Finns Study (YFS; N = 1667; age 34-49 years). EAT thickness was measured from parasternal long axis echocardiograms. Multivariable regression analysis was used to study potential EAT determinants. Possible effect modification of sex was addressed. Mean EAT thickness was 4.07 mm (95% CI 4.00-4.17). Multivariable analysis [β indicating percentage of change in EAT(mm) per one unit increase in determinant variable] indicated female sex (β = 11.0, P < 0.0001), type 2 diabetes (β = 14.0, P = 0.02), waist circumference (cm) (β = 0.38, P < 0.0001), systolic blood pressure (mmHg) (β = 0.18, P = 0.02) and red meat intake (g/day) (β = 0.02, P = 0.05) as EAT determinants. Sex-specific analysis revealed age (year) (β = 0.59, P = 0.01), alcohol intake (drinks/day) (β = 4.69, P = 0.006), heavy drinking (yes/no) (β = 30.4, P < 0.0001) as EAT determinants in women and fruit intake (g/day) (β = -1.0, P = 0.04) in men. In the YFS cohort, waist circumference, systolic blood pressure and red meat intake were directly associated with EAT among all participants. In women, age, alcohol intake, heavy drinking and type 2 diabetes associated directly with EAT, while an inverse association was observed between fruit intake and EAT in men.

The adipose-neural axis is involved in epicardial adipose tissue-related cardiac arrhythmias

Dysfunction of the sympathetic nervous system and increased epicardial adipose tissue (EAT) have been independently associated with the occurrence of cardiac arrhythmia. However, their exact roles in triggering arrhythmia remain elusive. Here, using an in vitro coculture system with sympathetic neurons, cardiomyocytes, and adipocytes, we show that adipocyte-derived leptin activates sympathetic neurons and increases the release of neuropeptide Y (NPY), which in turn triggers arrhythmia in cardiomyocytes by interacting with the Y1 receptor (Y1R) and subsequently enhancing the activity of the Na+/Ca2+ exchanger (NCX) and calcium/calmodulin-dependent protein kinase II (CaMKII). The arrhythmic phenotype can be partially blocked by a leptin neutralizing antibody or an inhibitor of Y1R, NCX, or CaMKII. Moreover, increased EAT thickness and leptin/NPY blood levels are detected in atrial fibrillation patients compared with the control group. Our study provides robust evidence that the adipose-neural axis contributes to arrhythmogenesis and represents a potential target for treating arrhythmia.

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.

Epicardial Atrial Fat at Cardiac Magnetic Resonance Imaging and AF Recurrence after Transcatheter Ablation

The relationship between epicardial adipose tissue (EAT) and atrial fibrillation (AF) has gained interest in recent years. The previous literature on the topic presents great heterogeneity, focusing especially on computed tomography imaging. The aim of the present study is to determine whether an increased volume of left atrial (LA) EAT evaluated at routine pre-procedural cardiac magnetic resonance imaging (MRI) relates to AF recurrences after catheter ablation. A total of 50 patients undergoing AF cryoballoon ablation and pre-procedural cardiac MRI allowing quantification of LA EAT were enrolled. In one patient, the segmentation of LA EAT could not be achieved. After a median follow-up of 16.0 months, AF recurrences occurred in 17 patients (34%). The absolute volume of EAT was not different in patients with and without AF recurrences (10.35 mL vs. 10.29 mL; p-value = 0.963), whereas the volume of EAT indexed on the LA volume (EATi) was lower, albeit non-statistically significant, in patients free from arrhythmias (12.77% vs. 14.06%; p-value = 0.467). The receiver operating characteristic curve testing the ability of LA EATi to predict AF recurrence after catheter ablation showed sub-optimal performance (AUC: 0.588). The finest identified cut-off of LA EATi was 10.65%, achieving a sensitivity of 0.5, a specificity of 0.82, a positive predictive value of 0.59 and a negative predictive value of 0.76. Patients with values of LA EATi lower than 10.65% showed greater survival, free from arrhythmias, than patients with values above this cut-off (84% vs. 48%; p-value = 0.04). In conclusion, EAT volume indexed on the LA volume evaluated at cardiac MRI emerges as a possible independent predictor of arrhythmia recurrence after AF cryoballoon ablation. Nevertheless, prospective studies are needed to confirm this finding and eventually sustain routine EAT evaluation in the management of patients undergoing AF catheter ablation.

Circulating adipose tissue proteins involved in atrial fibrillation: An explorative scoping review

Obesity increases the risk of atrial fibrillation (AF), potentially through proteins secreted by adipose tissue (AT) that affect atrial electrical and structural remodeling. We aim to give a comprehensive overview of circulating AT proteins involved in inflammation and fibrosis, that are associated with prevalent AF (paroxysmal or persistent) and the risk on developing new-onset AF. These include adipokines, defined as proteins enriched in AT as adiponectin, but also proteins less specific to AT. We systematically performed an explorative search for studies reporting associations between proteins secreted from cells residing in the AT and AF, and additionally assessed the effect of obesity on these proteins by a secondary search. The AT proteins involved in inflammation were mostly increased in patients with prevalent and new-onset AF, and with obesity, while the AT enriched adipokines were mostly not associated with AF. This review provides insight into circulating adipose tissue proteins involved in AF substrate formation.

Epicardial Adipose Tissue: A Precise Biomarker for Cardiovascular Risk, Metabolic Diseases, and Target for Therapeutic Interventions

Epicardial adipose tissue (EAT) is located between the heart muscle and visceral pericardium, where it has direct contact with coronary blood vessels. Elevated thickness of this tissue can induce local inflammation affecting the myocardium and the underlying coronary arteries, contributing to various cardiovascular diseases such as coronary artery disease, atrial fibrillation, or heart failure with preserved ejection fraction. Recent studies have identified EAT thickness as a simple and reliable biomarker for certain cardiovascular outcomes. Examples include the presence of atherosclerosis, incident cardiovascular disease (CVD) in individuals with type 2 diabetes mellitus (T2DM), and the prevalence of atrial fibrillation. Furthermore, EAT measurements can help to identify patients with a higher risk of developing metabolic syndrome. Since the EAT thickness can be easily measured using echocardiography, such examinations could serve as a useful and cost-effective preventive tool for assessing cardiovascular health. This review also summarizes therapeutical interventions aimed at reducing EAT. Reducing EAT thickness has been shown to be possible through pharmacological, surgical, or lifestyle-change interventions. Pharmaceutical therapies, including thiazolidinediones, glucagon-like peptide 1-receptor agonists, sodium-glucose cotransporter 2 inhibitors, dipeptidyl peptidase-4 inhibitors, and statins, have been shown to influence EAT thickness. Additionally, EAT thickness can also be managed more invasively through bariatric surgery, or noninvasively through lifestyle changes to diet and exercise routines.

Lifestyle Medicine: An Antidote to Cardiovascular Diseases

Despite numerous advances in basic understanding of cardiovascular disease pathophysiology, pharmacology, therapeutic procedures, and systems improvement, there hasn't been much decline in heart disease related mortality in the US since 2010. Hypertension and diet induced risk continue to be the leading causes of cardiovascular morbidity. Even with the excessive mortality associated with the COVID-19 pandemic, in 2020, heart disease remained the leading cause of death. Given the degree of disease burden, morbidity, and mortality, there is an urgent need to redirect medical professionals' focus towards prevention through simple and cost effective lifestyle strategies. However, current practice paradigm and financial compensation systems are mainly centered disease management and not health promotion. For example, the financial value placed on 3-10 min smoking cessation counseling (.24RVUs) is 47-fold lower than an elective PCI (11.21 RVUs). The medical community seems to be enamored with the latest and greatest technology, new devices, and surgical procedures. What if the greatest technology of all was simply the way we live every day? Perhaps when this notion is known by enough, we will switch to this lifestyle medicine technology to prevent disease in the first place.

Mediterranean diet and epicardial adipose tissue in patients with atrial fibrillation treated with ablation: a substudy of the 'PREDIMAR' trial

AIMS

To analyse the relationship between Mediterranean diet (MedDiet) adherence and epicardial adipose tissue (EAT) in patients with atrial fibrillation (AF) and the association between EAT or MedDiet adherence at baseline with AF recurrence after ablation.

METHODS AND RESULTS

We included 199 patients from the PREDIMAR trial (PREvención con DIeta Mediterránea de Arritmias Recurrentes), in a single centre in this substudy. All of them had a computed tomography with EAT measurement. Lifestyle and clinical characteristics were obtained at baseline. The traditional MedDiet pattern was defined according to the MedDiet Adherence Screener (MEDAS). Any documented AF > 30 s after ablation was considered a recurrence. Multivariable-adjusted linear and logistic regression models were run to assess the cross-sectional association of MedDiet with EAT, and of EAT with the AF type at baseline. Also, Cox regression models were used to prospectively assess the associations of MedDiet adherence and EAT with AF recurrences after ablation. Median EAT was 135 g (interquartile range: 112-177), and the mean MedDiet score was 7.75 ± 2 points. A higher MEDAS ≥ 7 that was associated with lower odds of an EAT ≥ 135 g [multivariable odds ratio (mOR) = 0.45; 95% CI = 0.22-0.91; P = 0.025] was significantly associated with persistent AF after adjusting for traditional risk factors (mOR: 2.22; 95% CI: 1.03-4.79; P = 0.042). No significant associations were observed between EAT ≥ 135 g and the risk of atrial tachyarrhythmia recurrences after ablation [multivariable-adjusted hazard ratio (mHR) = 1.18; 95% CI: 0.72-1.94; P = 0.512], or between MEDAS ≥ 7 and AF recurrence (mHR = 0.78; 95% CI: 0.47-1.31; P = 0.344).

CONCLUSION

In patients with AF, higher adherence to MedDiet is associated with a significantly lower amount of EAT. Epicardial adipose tissue ≥ 135 g was significantly associated with persistent AF.

The role of epicardial fat radiomic profiles for atrial fibrillation identification and recurrence risk with coronary CT angiography

OBJECTIVES

Fat radiomic profile (FRP) was a promising imaging biomarker for identifying increased cardiac risk. We hypothesize FRP can be extended to fat regions around pulmonary veins (PV), left atrium (LA), and left atrial appendage (LAA) to investigate their usefulness in identifying atrial fibrillation (AF) and the risk of AF recurrence.

METHODS

We analysed 300 individuals and grouped patients according to the occurrence and types of AF. We used receiver operating characteristic and survival curves analyses to evaluate the value of imaging biomarkers, including fat attenuation index (FAI) and FRP, in distinguishing AF from sinus rhythm and predicting post-ablation recurrence.

RESULTS

FRPs from AF-relevant fat regions showed significant performance in distinguishing AF and non-AF with higher AUC values than FAI (peri-PV: FRP = 0.961 vs FAI = 0.579, peri-LA: FRP = 0.923 vs FAI = 0.575, peri-LAA: FRP = 0.900 vs FAI = 0.665). FRPs from peri-PV, peri-LA, and peri-LAA were able to differentiate persistent and paroxysmal AF with AUC values of 0.804, 0.819, and 0.694. FRP from these regions improved AF recurrence prediction with an AUC of 0.929, 0.732, and 0.794. Patients with FRP cut-off values of ≥0.16, 0.38, and 0.26 had a 7.22-, 5.15-, and 4.25-fold higher risk of post-procedure recurrence, respectively.

CONCLUSIONS

FRP demonstrated potential in identifying AF, distinguishing AF types, and predicting AF recurrence risk after ablation. FRP from peri-PV fat depot exhibited a strong correlation with AF. Therefore, evaluating epicardial fat using FRP was a promising approach to enhance AF clinical management.

ADVANCES IN KNOWLEDGE

The role of epicardial adipose tissue (EAT) in AF had been confirmed, we focussed on the relationship between EAT around pulmonary arteries and LAA in AF which was still unknown. Meanwhile, we used the FRP to excavate more information of EAT in AF.

Opportunistic Extraction of Quantitative CT Biomarkers: Turning the Incidental Into Prognostic Information

The past two decades have seen a significant increase in the use of CT, with a corresponding rise in the mean population radiation dose. This rise in CT use has caused improved diagnostic certainty in conditions that were not previously routinely evaluated using CT, such as headaches, back pain, and chest pain. Unused data, unrelated to the primary diagnosis, embedded within these scans have the potential to provide organ-specific measurements that can be used to prognosticate or risk-profile patients for a wide variety of conditions. The recent increased availability of computing power, expertise and software for automated segmentation and measurements, assisted by artificial intelligence, provides a conducive environment for the deployment of these analyses into routine use. Data gathering from CT has the potential to add value to examinations and help offset the public perception of harm from radiation exposure. We review the potential for the collection of these data and propose the incorporation of this strategy into routine clinical practice.

Intersection of sepsis, atrial fibrillation, and severe obesity: a population-based analysis in the United States

BACKGROUND

Atrial fibrillation (AF) is an indicator of poor prognosis in patients with sepsis and can increase the risk of stroke and mortality. Data on the impact of severe obesity on the outcomes of sepsis complicated by AF remains poorly understood.

METHODS

National Inpatient Sample (2018) and ICD-10 CM codes were used to identify the principal sepsis admissions with AF. We assessed comorbidities and outcomes of sepsis in people without obesity (BMI < 30) vs. non-severe obesity (BMI 30-35) and severe obesity (BMI > 35) cohorts. We also did a subgroup analysis to further stratify obesity based on metabolic health and analyzed the findings. The primary outcomes were the prevalence and adjusted odds of AF, AF-associated stroke, and all-cause mortality in sepsis by obesity status. Multivariable regression analyses were adjusted for patient- and hospital-level characteristics and comorbidities.

RESULTS

Our main analysis showed that of the 1,345,595 sepsis admissions, the severe obesity cohort was the youngest (median age 59 vs. non-severe 64 and people without obesity 68 years). Patients with obesity, who were often female, were more likely to have hypertension, diabetes, congestive heart failure, chronic pulmonary disease, and chronic kidney disease. The crude prevalence of AF was highest in non-severe obesity (19.9%). The adjusted odds of AF in non-severe obesity (OR 1.21; 95% CI:1.16-1.27) and severe obesity patients with sepsis (OR 1.49; 95% CI:1.43-1.55) were significantly higher than in people without obesity (p < 0.001). Paradoxically, the rates of AF-associated stroke (1%, 1.5%, and 1.7%) and in-hospital mortality (3.3%, 4.9%, and 7.1%) were lowest in the severe obesity cohort vs. the non-severe and people without obesity cohorts, respectively. On multivariable regression analyses, the all-cause mortality revealed lower odds in sepsis-AF patients with severe obesity (OR 0.78; 95% CI:0.67-0.91) or non-severe obesity (OR 0.63; 95% CI:0.54-0.74) vs. people without obesity. There was no significant difference in stroke risk.

CONCLUSIONS

A higher prevalence of cardiovascular comorbidities can be linked to a higher risk of AF in people with obesity and sepsis. Paradoxically, lower rates of stroke and all-cause mortality secondary to AF in people with obesity and sepsis warrant further investigation.

Visceral adiposity in patients with lipomatous hypertrophy of the interatrial septum

Lipomatous hypertrophy of the interatrial septum (LHIS) is a benign cardiac mass determined by abnormal deposition of adipose tissue in the interatrial septum. The quantitative relationship between LHIS and visceral adiposity has not been explored to date.In this retrospective study, three groups of consecutive patients undergoing CT imaging were enrolled: L + with LHIS, L- without LHIS, and LO- without both LHIS and history of malignancies. Areas of total adipose tissue (TAT), visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT) and LHIS areas were calculated on CT images. The relationship between LHIS and abdominal fat distribution was investigated with linear regression models. Bonferroni correction was applied to account for multiple testing. Statistical significance was set at 5%. In this study we enrolled a total of 175 subjects: 58 (33.14%) with LHIS (L +), 51(29.14%) without LHIS (L-) and 66 (37.71%) without both LHIS and medical history of malignancies (LO-). VAT (coeff: 105.82; 95% CI 59.37-152.27), SAT (coeff: 74.59; 95% CI 31.63-117.54), and TAT (coeff: 190.37; 95% CI 115.02-265.72), were significantly higher in L + patients. Moreover, VAT (coeff: 24.95; 95% CI 6.94-42.96) and TAT (coeff: 36.58; 95% CI 8.75-64.41) were statistically significant linear predictors for LHIS area. Here, we report a novel association between LHIS and visceral adiposity using a quantitative CT-based imaging approach. The results are of great importance also because they might drive early identification of subjects with LHIS at risk for visceral obesity, and trigger lifestyle interventions aimed at weight loss.

Heart failure with preserved ejection fraction and atrial fibrillation: clinical management in the context of recent therapeutic advances in heart failure and electrophysiology

Heart failure with preserved ejection fraction (HFpEF) and atrial fibrillation (AF) have emerged as major age-related epidemics within cardiology. Both conditions carry overlapping symptomatology, and delineating between AF and HFpEF from a diagnostic standpoint is challenging as echocardiographic and biomarker assessments used to diagnose HFpEF may be impacted by AF. Indeed, these two conditions are commonly found in the same individual, so much so that AF has been used in proposed diagnostic criteria for HFpEF. The frequent concomitant presence of these two conditions is associated with poorer quality of life, exertional capacity, as well as increased risk for decompensated heart failure and all-cause mortality. Though these deleterious effects of AF in HFpEF patients are well described, we currently have only a superficial understanding of the complex interplay between these two conditions. Preliminary studies on intervening in AF in HFpEF are very small, with mixed data on whether modifying the natural history of AF can lead to improvement in heart failure (HF) outcomes in HFpEF. In this review, we will describe the clinical implications of carrying both cardiovascular conditions, address recent advances in HFpEF and AF, and highlight preliminary studies targeted at reduction of effects associated with AF burden in HFpEF.

Impact of Obesity on Atrial Fibrillation Pathogenesis and Treatment Options

Atrial fibrillation (AF) is the most common cardiac arrhythmia. AF increases the risk of stroke, heart failure, dementia, and hospitalization. Obesity significantly increases AF risk, both directly and indirectly, through related conditions, like hypertension, diabetes, and heart failure. Obesity-driven structural and electrical remodeling contribute to AF via several reported mechanisms, including adiposity, inflammation, fibrosis, oxidative stress, ion channel alterations, and autonomic dysfunction. In particular, expanding epicardial adipose tissue during obesity has been suggested as a key driver of AF via paracrine signaling and direct infiltration. Weight loss has been shown to reverse these changes and reduce AF risk and recurrence after ablation. However, studies on how obesity affects pharmacologic or interventional AF treatments are limited. In this review, we discuss mechanisms by which obesity mediates AF and treatment outcomes, aiming to provide insight into obesity-drug interactions and guide personalized treatment for this patient subgroup.

2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation" provides recommendations to guide clinicians in the treatment of patients with atrial fibrillation.

METHODS

A comprehensive literature search was conducted from May 12, 2022, to November 3, 2022, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through November 2022, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Atrial fibrillation is the most sustained common arrhythmia, and its incidence and prevalence are increasing in the United States and globally. Recommendations from the "2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" and the "2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing atrial fibrillation and thromboembolic risk assessment, anticoagulation, left atrial appendage occlusion, atrial fibrillation catheter or surgical ablation, and risk factor modification and atrial fibrillation prevention have been developed.

2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Patients With Atrial Fibrillation" provides recommendations to guide clinicians in the treatment of patients with atrial fibrillation.

METHODS

A comprehensive literature search was conducted from May 12, 2022, to November 3, 2022, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through November 2022, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Atrial fibrillation is the most sustained common arrhythmia, and its incidence and prevalence are increasing in the United States and globally. Recommendations from the "2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" and the "2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing atrial fibrillation and thromboembolic risk assessment, anticoagulation, left atrial appendage occlusion, atrial fibrillation catheter or surgical ablation, and risk factor modification and atrial fibrillation prevention have been developed.

Risk factors modification in atrial fibrillation: a brief review

INTRODUCTION

Atrial fibrillation (AF) is a supraventricular arrhythmia characterized by fibrillatory waves in the atria with an irregular ventricular rhythm. It is the most common arrhythmia treated in clinical practice. AF is associated with approximately five-fold increase in risk of cerebrovascular accident (stroke) and two-fold increase in cognitive dysfunction and all-cause mortality.

AREAS COVERED

Multiple risk factors have been identified for development of AF including age, hypertension, diabetes, and obesity. Primary and secondary prevention strategies aimed at reducing the incidence of AF can have a dramatic clinical and economic impact. Multiple studies have shown that lifestyle interventions can reduce predisposing factors, reverse the pathophysiology behind AF, and decrease disease burden. In this brief review we aim at exploring the current state of knowledge regarding risk factor modifications that decrease incidence and prevalence of AF.

EXPERT OPINION

This is an evolving field of research and further studies to elucidate the magnitude of effect of these interventions as well as the pathophysiological mechanisms driving these effects are underway.

MicroRNAs in extracellular vesicles released from epicardial adipose tissue promote arrhythmogenic conduction slowing

Background

Patients with excess epicardial adipose tissue (EAT) are at increased risk of developing cardiac arrhythmias. EAT promotes arrhythmias by depolarizing the resting membrane of cardiomyocytes, which slows down conduction and facilitates re-entrant arrhythmias. We hypothesized that EAT slows conduction by secreting extracellular vesicles (EVs) and their microRNA (miRNA) cargo.

Objective

We aimed to determine the role of EAT-derived EVs and their miRNA cargo in conduction slowing.

Methods

EAT and subcutaneous adipose tissue (SAT) were collected from patients with atrial fibrillation. Adipose tissue explants were incubated in culture medium and secretome was collected. The numbers of EVs in the EAT and SAT secretome were measured by calibrated flow cytometry. EVs in the EAT secretome were isolated by size exclusion chromatography and miRNAs were sequenced. Pathway analysis was performed to predict candidates involved in cardiac electrophysiology. The candidates were validated in the EAT and SAT by quantitative real-time polymerase chain reaction. Finally, miRNA candidates were overexpressed in neonatal rat ventricular myocytes.

Results

The EV concentration was higher in the EAT secretome than in the SAT and control secretomes. miRNA sequencing of EAT-derived EVs detected a total of 824 miRNAs. Pathway analysis led to the identification of 7 miRNAs potentially involved in regulation of cardiac resting membrane potential. Validation of those miRNA candidates showed that they were all expressed in EAT, and that miR-1-3p and miR-133a-3p were upregulated in EAT in comparison with SAT. Overexpression of miR-1-3p and miR-133a-3p in neonatal rat ventricular myocytes led to conduction slowing and reduced Kcnj2 and Kcnj12 expression.

Conclusion

miR-1-3p and miR-133a-3p are potential mediators of EAT arrhythmogenicity.

Epicardial adipose tissue, metabolic disorders, and cardiovascular diseases: recent advances classified by research methodologies

Epicardial adipose tissue (EAT) is located between the myocardium and visceral pericardium. The unique anatomy and physiology of the EAT determines its great potential in locally influencing adjacent tissues such as the myocardium and coronary arteries. Classified by research methodologies, this study reviews the latest research progress on the role of EAT in cardiovascular diseases (CVDs), particularly in patients with metabolic disorders. Studies based on imaging techniques demonstrated that increased EAT amount in patients with metabolic disorders is associated with higher risk of CVDs and increased mortality. Then, in-depth profiling studies indicate that remodeled EAT may serve as a local mediator of the deleterious effects of cardiometabolic conditions and plays a crucial role in CVDs. Further, in vitro coculture studies provided preliminary evidence that the paracrine effect of remodeled EAT on adjacent cardiomyocytes can promote the occurrence and progression of CVDs. Considering the important role of EAT in CVDs, targeting EAT might be a potential strategy to reduce cardiovascular risks. Several interventions have been proved effective in reducing EAT amount. Our review provides valuable insights of the relationship between EAT, metabolic disorders, and CVDs, as well as an overview of the methodological constructs of EAT-related studies.

Recent advances in artificial intelligence for cardiac CT: Enhancing diagnosis and prognosis prediction

Recent advances in artificial intelligence (AI) for cardiac computed tomography (CT) have shown great potential in enhancing diagnosis and prognosis prediction in patients with cardiovascular disease. Deep learning, a type of machine learning, has revolutionized radiology by enabling automatic feature extraction and learning from large datasets, particularly in image-based applications. Thus, AI-driven techniques have enabled a faster analysis of cardiac CT examinations than when they are analyzed by humans, while maintaining reproducibility. However, further research and validation are required to fully assess the diagnostic performance, radiation dose-reduction capabilities, and clinical correctness of these AI-driven techniques in cardiac CT. This review article presents recent advances of AI in the field of cardiac CT, including deep-learning-based image reconstruction, coronary artery motion correction, automatic calcium scoring, automatic epicardial fat measurement, coronary artery stenosis diagnosis, fractional flow reserve prediction, and prognosis prediction, analyzes current limitations of these techniques and discusses future challenges.

Uncovering the Role of Epicardial Adipose Tissue in Heart Failure With Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is the most common form of heart failure. Obesity is a modifiable risk factor of HFpEF; however, body mass index provides limited information on visceral adiposity and patients with similar anthropometrics can present variable cardiovascular risk. Epicardial adipose tissue (EAT) is the closest fat deposit to the heart and has been proposed as a biomarker of visceral adiposity. EAT may be particularly important for cardiac function, because of its location (under the pericardium) and because it acts as a metabolically active endocrine organ (which can produce both beneficial and detrimental cytokines). In this paper, the authors review the role of EAT in normal and pathologic conditions and discuss the noninvasive imaging modalities that allow its identification. This review highlights EAT implications in HFpEF and discuss new therapies that act on EAT and might also exert beneficial effects on the cardiovascular system.

Cardiac Magnetic Resonance in Patients with Suspected Tachycardia-Induced Cardiomyopathy: The Impact of Late Gadolinium Enhancement and Epicardial Fat Tissue

Tachycardia-induced cardiomyopathy (TIC) is a reversible subtype of dilated cardiomyopathy (DCM) resulting from sustained supraventricular or ventricular tachycardia and diagnosed by the normalization of left ventricular ejection fraction (LVEF) after stable sinus rhythm restoration. The aim of this study was to determine the contribution of cardiac magnetic resonance (CMR) to the differential diagnosis of TIC and DCM with persistent atrial arrythmias in patients hospitalized for the first time with heart failure (HF) with reduced LVEF of nonischemic origin. A total of 29 patients (age: 58.2 ± 16.9 years; males: 65.5%; average EF: 37.0 ± 9.5%) with persistent atrial tachyarrhythmia and first decompensation of HF without known coronary artery diseases were included in this study. The patients successfully underwent cardioversion and were observed for 30 days. The study population was divided into groups of responders (TIC patients; N = 16), which implies achieving FF > 50% or its increase > 10% in 30 days of TIC, and non-responders (N = 13). The increase in left ventricle (LV) volumes measured using CMR was significantly higher in the non-responder group when compared with the responders (114.8 mL ± 25.1 vs. 68.1 mL ± 10.5, respectively, p < 0.05). Non-responders also demonstrated decreased interventricular septum thickness (9.1 ± 0.8 vs.11.5 ± 1.3, respectively, p < 0.05). Late gadolinium enhancement (LGE) was observed in 12 patients (41.4%). The prevalence of LGE was increased in the non-responder group (25.0% vs. 65.1%, respectively, p = 0.046). Notably, a septal mid-wall LGE pattern was found exclusively in the non-responders. Epicardial adipose tissue thickness was decreased in the non-responder group versus the TIC patients. Conclusion: Patients with TIC were found to have smaller atrial and ventricular dimensions in comparison to patients with DCM. In addition, LGE was more common in DCM patients.

Gender-Related Differences in Atrial Substrate in Patients with Atrial Fibrillation

Gender-related differences have been reported in patients who underwent pulmonary vein isolation (PVI). Atrial substrate plays a role in the outcomes after ablation but gender-related differences in atrial substrate have never been described in detail. We sought to analyze gender-related differences in atrial remodeling (spontaneous low-voltage zones [LVZs]) and their clinical relevance after PVI. We conducted a prospective multicenter study, including consecutive patients who underwent first PVI-only atrial fibrillation (AF) ablation. LVZs were analyzed on high-density electroanatomical maps collected with multipolar catheter, before PVI. In total, 262 patients (61 ± 11 years, 31% female, 50% persistent AF) were followed for 28 months. In women, LVZs were larger (10% vs 4% of left atrial surface [p <0.001]) and female gender was independently associated with fourfold higher risk of having advanced (LVZ > 15%) atrial remodeling (odds ratio 4.56, p <0.001). AF recurrence-free survival was not different between men and women (log-rank p = 0.2). Although LVZs were independently associated higher AF recurrences at multivariate analysis (hazard ratio [HR] 1.2, p = 0.038), female gender was not (HR 1.4, p = 0.211). Specifically, the LVZ cutoff to predict outcomes was different in men and women: >5% in men (HR 3.0, p <0.001), >15% in women (HR 2.7, p = 0.02). In conclusion, women have more widespread LVZ in all left atrial regions. Despite more extensive atrial remodeling, the AF recurrence rate is similar in men and women, and LVZs become prognostic in women only at high burden (>15%). LVZs seem to have a different prognostic role in men and women.

Association between cardiovascular risk factors and atrial fibrillation

Background

The most prevalent sustained arrhythmia in medical practice, atrial fibrillation (AF) is closely associated with a high risk of cardiovascular disease. Nevertheless, the risk of AF associated with cardiovascular risk factors has not been well elucidated. We pooled all published studies to provide a better depiction of the relationship among cardiovascular risk factors with AF.

Methods

Studies were searched in the MEDLINE, Web of Science, and EMBASE databases since initiation until January 15, 2022. Prospective cohort studies assessing the relationship a minimum of single cardiovascular risk factors to AF incidence were included if they contained adequate data for obtaining relative risks (RR) and 95% confidence intervals (CI). Random-effects models were utilized to perform independent meta-analyses on each cardiovascular risk factor. PROSPERO registry number: CRD42022310882.

Results

A total of 17,098,955 individuals and 738,843 incident cases were reported for data from 101 studies included in the analysis. In all, the risk of AF was 1.39 (95% CI, 1.30-1.49) for obesity, 1.27 (95% CI, 1.22-1.32) per 5 kg/m2 for increase in body mass index, 1.19 (95% CI, 1.10-1.28) for former smokers, 1.23 (95% CI, 1.09-1.38) for current smokers, 1.31 (95% CI, 1.23-1.39) for diabetes mellitus, 1.68 (95% CI, 1.51-1.87) for hypertension, and 1.12 (95% CI, 0.95-1.32) for dyslipidemia.

Interpretation

Adverse cardiovascular risk factors correlate with an increased risk of AF, yet dyslipidemia does not increase the risk of AF in the general population, potentially providing new insights for AF screening strategies among patients with these risk factors.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/, PROSPERO identifier (CRD42022310882).

Association of pericoronary adipose tissue with atrial fibrillation recurrence after ablation based on computed tomographic angiography

PURPOSE

Quantitative measurement of pericoronary adipose tissue volume (PCATV) and fat attenuation index (FAI) has mostly been used in the study of coronary artery related diseases but rarely in the relationship with atrial fibrillation (AF). This study was conducted to investigate the correlation of PCATV and FAI with the AF recurrence after ablation and the clinical significance.

MATERIALS AND METHODS

Patients with continuous AF who underwent radiofrequency ablation and computed tomographic angiography (CTA) were retrospectively enrolled. The PCATV, FAI, epicardial adipose tissue volume (EATV) and EAT density (EATD) arround the three main branches of the coronary arteries (LAD, LCX, and RCA) were measured quantitatively with cardiac function software and analyzed.

RESULTS

189 patients with continuous AF who underwent radiofrequency ablation for the first time were enrolled. After 12-month follow-up with a mean follow-up time of 10.93 ± 0.16 months, 47 (24.9%) patients were confirmed to have AF recurrence. The 3 V-FAI (- 81.17 ± 4.27 vs. - 83.31 ± 4.59 HU, P = 0.005), LCX-FAI (median - 77 vs. median - 81HU, P < 0.001), EATV (median 141.14vs. median 125.39 ml, P = 0.010), and EATVI (median 70.77 vs. 66.73 ml/m2, P = 0.008) were significantly increased in the recurrence group. EATVI (OR 1.043, 95% CI 1.020-1.066) and LCX-FAI (OR 1.254, 95% CI 1.145-1.374) were two significant independent risk factors for AF recurrence. In the comparison of ROC, the predictive value of LCX-FAI (cut-off value of >- 81.5 HU, area under the curve (AUC) of 0.722) was higher than that of EATVI (cut-off value > 81.07 ml/m2, AUC of 0.630).

CONCLUSION

EATVI and LCX-FAI were related to recurrence of AF after ablation and have important clinical value in predicting the AF recurrence.