Epicardial fat thickness and coronary artery disease correlate independently of obesity

LA Epicardial Adipose Tissue Assessed by CTA Associated With Silent Cerebral Infarcts in Patients With AF Catheter Ablation

INTRODUCTION

Left atrium epicardial adipose tissue (LA-EAT) is an atrial cardiomyopathy marker associated with ischemic stroke. However, the relationship between EAT and silent cerebral infarcts (SCI) is unclear. This study investigated the effect of EAT on the risk of SCI after atrial fibrillation catheter ablation (AFCA).

METHODS

This was a single-center prospective study. We consecutively enrolled patients who underwent AFCA from October 2019 to February 2024. All patients completed brain magnetic resonance imaging (MRI) within 24-48 h after AFCA. SCI was defined as new single or multiple brain injuries detectable on MRI without clinical manifestations or neurolocalization signs.

RESULTS

A total of 341 patients were enrolled, including 56 (16.4%) with SCI. Pearson correlation analysis showed that LA-EAT volume index moderately correlated with left atrial volume index (r = 0.391, p < 0.001). After adjusting for potential confounding factors, multivariate analysis showed that LA-EAT volume index (OR = 1.10; 95% CI: 1.03-1.16, p = 0.002) and LA-EAT attenuation (OR = 1.08; 95% CI: 1.03-1.14, p = 0.003) were independent factors for SCI after AFCA. Integrating LA-EAT volume index and LA-EAT attenuation could statistically improve the ability of the model to predict SCI after AFCA (NRI 0.763, 95% CI: 0.5054-1.0196, p < 0.001; IDI 0.043, 95% CI: 0.0133-0.0733, p = 0.005).

CONCLUSION

LA-EAT is associated with SCI after AFCA and larger LA-EAT volume is an independent risk factor for SCI. Integrating LA-EAT can statistically improve the risk assessment model for SCI after AFCA.

SGLT2 inhibitors reduce epicardial adipose tissue more than GLP-1 agonists or exercise interventions in patients with type 2 diabetes mellitus and/or obesity: A systematic review and network meta-analysis

BACKGROUND

Epicardial adipose tissue (EAT) plays a significant role in several cardiovascular diseases. As a correctable risk factor and potential therapeutic target, reducing EAT has multiple cardiovascular benefits, especially in those with abnormal glucolipid metabolism. The objective of this research was to compare the effects of sodium-glucose cotransporter 2 (SGLT2) inhibitors, glucagon-like peptide-1 (GLP-1) agonists, and exercise on the thickness of EAT and indicators of glucolipid metabolism in people with type 2 diabetes mellitus (T2DM), obesity, and T2DM with obesity.

METHODS

We searched four electronic databases: PubMed, EMBASE, the Cochrane Library, and Web of Science for articles before 31 January 2024, regardless of language. We included randomized controlled trials and a small number of case-control studies in this network meta-analysis. Differences in mean changes in EAT, body mass index, and glucolipid metabolism-related metrics were assessed.

RESULTS

A comprehensive analysis was conducted on 16 trials (15 randomized controlled trials and one case-control study), comprising a total of 867 people. SGLT2 inhibitors were significantly better at reducing EAT than placebo (standard mean different [SMD] = -0.85 cm [95% confidence interval (CI) -1.39, -0.31]); a similar result was observed for exercise compared with placebo (SMD = -0.78 cm [95% CI -1.37, -0.18]). SGLT2 inhibitors were also significantly better at reducing EAT than GLP-1 agonists and conventional hypoglycaemic therapy (e.g., metformin or insulin; SMD = -0.74 cm [95% CI -1.45, -0.02] and SMD = -1.69 cm [95% CI -2.38, -0.99], respectively). SGLT2 inhibitors were significantly better than placebo at reducing body mass index (MD = -0.90 kg/m2 [95% CI -1.14, -0.66]) and glycosylated haemoglobin (MD = -0.52% [95%CI -0.86, -0.18]). A similar result was observed when comparing GLP-1 agonists and placebo (MD = -0.48% [95% CI -0.93, -0.03]). Changes in total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol were not statistically significant between interventions.

CONCLUSION

SGLT2 inhibitors have a distinct advantage over both placebo and other therapies at lowering EAT thickness, a result supported by direct comparisons and surface under the cumulative ranking curve analysis. Therefore, SGLT2 inhibitors should be prioritized as a treatment to reduce EAT in individuals with aberrant glucolipid levels, such as patients with T2DM and/or obesity.

Epicardial fat links obesity to cardiovascular diseases

Patients with obesity have been historically associated with higher risk to develop cardiovascular diseases (CVD). However, regional, visceral, organ specific adiposity seems to play a stronger role in the development of those cardiovascular diseases than obesity by itself. Epicardial adipose tissue is the visceral fat depot of the heart with peculiar anatomy, regional differences, genetic profile and functions. Due to its unobstructed contiguity with heart and intense pro inflammatory and pro arrhythmogenic activities, epicardial fat is directly involved in major obesity-related CVD complications, such as coronary artery disease (CAD), atrial fibrillation (AF) and heart failure (HF). Current and developing imaging techniques can measure epicardial fat thickness, volume, density and inflammatory status for the prediction and stratification of the cardiovascular risk in both symptomatic and asymptomatic obese individuals. Pharmacological modulation of the epicardial fat with glucagon like peptide-1 receptor (GLP1R) analogs, sodium glucose transporter-2 inhibitors, and potentially dual (glucose-dependent insulinotropic polypeptide -GLP1R) agonists, can reduce epicardial fat mass, resume its original cardio-protective functions and therefore reduce the cardiovascular risk. Epicardial fat assessment is poised to change the traditional paradigm that links obesity to the heart.

Association of Epicardial Fat with Diastolic and Vascular Functions in Children with Type 1 Diabetes

We aimed to examine the relationship between epicardial fat thickness (EFT) measured by echocardiography and cardiovascular functional parameters in children with type 1 diabetes mellitus (T1DM). The study included 50 type 1 diabetic children and 50 healthy subjects matched by sex, age, and body mass index. In addition to laboratory tests, all participants underwent transthoracic echocardiography for EFT, cardiac dimensions and left ventricular functions, and ultrasonographic examination for brachial artery flow-mediated dilation (FMD) response and carotid intima-media thickness (CIMT). Multivariate linear regression was used to analyze the relationship between EFT and CIMT, FMD, lateral mitral E' velocity, and mitral E/E' ratio. EFT was significantly increased in diabetic children compared with controls (P < 0.001). In comparison with controls diabetic children had significantly increased mitral A, decreased lateral mitral E', decreased mitral E/A ratio, decreased lateral mitral E'/A' ratio, and increased mitral E/E' ratio (P < 0.001). FMD response was significantly lower in diabetic group versus controls (P < 0.001) and CIMT was significantly increased in diabetics versus controls (P = 0.03). EFT was negatively correlated with lateral mitral E' velocity (r =  - 0.613, P < 0.001), positively correlated with mitral E/E' ratio (r = 0.60, P < 0.001), positively correlated with CIMT (r = 0.881, P < 0.001), and negatively correlated with FMD (r =  - 0.533, P < 0.001). By multivariate regression analysis, the EFT was independently and positively associated with CIMT mean and E/E' mean and negatively associated with FMD mean and E' mean. The cut-off point for EFT as predictor of endothelial dysfunction was 6.95 mm. Our findings suggest that children with T1DM have subclinical LV diastolic and vascular endothelial dysfunctions associated with increased EFT.

Recent Progress in Epicardial and Pericardial Adipose Tissue Segmentation and Quantification Based on Deep Learning: A Systematic Review

Epicardial and pericardial adipose tissues (EAT and PAT), which are located around the heart, have been linked to coronary atherosclerosis, cardiomyopathy, coronary artery disease, and other cardiovascular diseases. Additionally, the volume and thickness of EAT are good predictors of CVD risk levels. Manual quantification of these tissues is a tedious and error-prone process. This paper presents a comprehensive and critical overview of research on the epicardial and pericardial adipose tissue segmentation and quantification methods, evaluates their effectiveness in terms of segmentation time and accuracy, provides a critical comparison of the methods, and presents ongoing and future challenges in the field. Described methods are classified into pericardial adipose tissue segmentation, direct epicardial adipose tissue segmentation, and epicardial adipose tissue segmentation via pericardium delineation. A comprehensive categorization of the underlying methods is conducted with insights into their evolution from traditional image processing methods to recent deep learning-based methods. The paper also provides an overview of the research on the clinical significance of epicardial and pericardial adipose tissues as well as the terminology and definitions used in the medical literature.

Epicardial adipose tissue in contemporary cardiology

Interest in epicardial adipose tissue (EAT) is growing rapidly, and research in this area appeals to a broad, multidisciplinary audience. EAT is unique in its anatomy and unobstructed proximity to the heart and has a transcriptome and secretome very different from that of other fat depots. EAT has physiological and pathological properties that vary depending on its location. It can be highly protective for the adjacent myocardium through dynamic brown fat-like thermogenic function and harmful via paracrine or vasocrine secretion of pro-inflammatory and profibrotic cytokines. EAT is a modifiable risk factor that can be assessed with traditional and novel imaging techniques. Coronary and left atrial EAT are involved in the pathogenesis of coronary artery disease and atrial fibrillation, respectively, and it also contributes to the development and progression of heart failure. In addition, EAT might have a role in coronavirus disease 2019 (COVID-19)-related cardiac syndrome. EAT is a reliable potential therapeutic target for drugs with cardiovascular benefits such as glucagon-like peptide 1 receptor agonists and sodium–glucose co-transporter 2 inhibitors. This Review provides a comprehensive and up-to-date overview of the role of EAT in cardiovascular disease and highlights the translational nature of EAT research and its applications in contemporary cardiology.

In this Review, Iacobellis provides a comprehensive overview of the role of epicardial adipose tissue (EAT) in cardiovascular disease, including coronary artery disease, heart failure and atrial fibrillation, discusses imaging techniques for EAT assessment and highlights the therapeutic potential of targeting EAT in cardiovascular disease.

Epicardial adipose tissue (EAT) has anatomical and functional interactions with the heart owing to the shared circulation and the absence of muscle fascia separating the two organs.

EAT can be clinically measured with cardiac imaging techniques that can help to predict and stratify cardiovascular risk.

Regional distribution of EAT is important because pericoronary EAT and left atrial EAT differently affect the risk of coronary artery diseases and atrial fibrillation, respectively.

EAT has a role in the development of several cardiovascular diseases through complex mechanisms, including gene expression profile, pro-inflammatory and profibrotic proteome, neuromodulation, and glucose and lipid metabolism.

EAT could be a potential therapeutic target for novel cardiometabolic medications that modulate adipose tissue such as glucagon-like peptide 1 receptor agonists and sodium–glucose co-transporter 2 inhibitors.

EAT might be a reservoir of severe acute respiratory syndrome coronavirus 2 and an amplifier of coronavirus disease 2019 (COVID-19)-related cardiac syndrome.

Cardiovascular risk reduction throughout GLP-1 receptor agonist and SGLT2 inhibitor modulation of epicardial fat

Epicardial adipose tissue is a novel cardiovascular risk factor. It plays a role in the progression of coronary artery disease, heart failure and atrial fibrillation. Given its rapid metabolism, clinical measurability, and modifiability, epicardial fat works well as therapeutic target of drugs modulating the adipose tissue. Epicardial fat responds to glucagon-like peptide 1 receptor agonists (GLP1A) and sodium glucose co-transporter 2 inhibitors (SGLT2i). GLP-1A and SGLT2i provide weight loss and cardiovascular protective effects beyond diabetes control, as recently demonstrated. The potential of modulating the epicardial fat morphology and genetic profile with targeted pharmacological agents can open new avenues in the pharmacotherapy of diabetes and obesity, with particular focus on cardiovascular risk reduction.

Adipokine gene expression in adipocytes isolated from different fat depots of coronary artery disease patients

To compare DPP4, LCN2, NAMPT, ITLN1, APLN mRNA levels in adipocytes isolated from the biopsies of subcutaneous, epicardial and perivascular fat obtained from 25 patients with coronary artery disease. Gene expression signature was determined by RT-qPCR with hydrolysis probes. We found DPP4 and APLN mRNA was higher expressed only in adipocytes isolated from epicardial adipose tissue compared to the subcutaneous fat. The ITLN1 gene was overexpressed in epicardial adipose tissue compared to both subcutaneous and perivascular tissues. APLN mRNA expression was positively correlated with total and LDL cholesterol plasma level, and DPP4 mRNA expression - with VLDL cholesterol concentration. Thus, adipocytes isolated from different adipose depots are characterised by differential gene expression of adipokines. Epicardial adipose tissue is of particular interest in the context of its function, molecular and genetic mechanisms of regulation of the cardiovascular system and as a therapeutic target for correction of adipose tissue-induced effects on health.

Increased estimated fat-free mass and fat mass associated with improved clinical outcome in heart failure

BACKGROUND

Increased weight measured by body mass index is associated with better clinical outcomes in heart failure (HF). The effect of specific components of body mass on outcome is limited. We evaluated the impact of fat-free mass and fat mass on mortality and cardiovascular hospitalization in a large real-world cohort of patients with chronic HF.

METHODS

Body measurements were assessed in patients with chronic HF. Fat-free mass, fat mass and waist circumference were calculated based on specifically derived formulas.

RESULTS

The cohort included 6328 HF patients. Mean follow-up was 744 days. Increased body composition indices including body mass index, fat-free mass index and fat mass index, per cent body fat and waist circumference were associated with better survival. Cox regression analysis after adjustment for other significant parameters demonstrated that these indices were all associated with improved survival. The strongest association was seen with fat-free mass index with a graded increase in survival; lowest death in the highest quartile compared to reference second quartile (hazard ratio 0.79, 95% confidence interval 0.67-0.93, P < .01). There was no interaction with sex or HF type. Analysis of the clinical outcome of death and cardiovascular hospitalization demonstrated that a worse prognosis was in the lowest quartile of all the indices. A sensitivity analysis, analysing these indices as continuous parameters using restricted cubic splines, demonstrated a clear continuous association between these indices and increased survival in both sexes.

CONCLUSIONS

Body mass including fat-free mass and fat mass was associated with improved survival in patients with HF.

Association of epicardial fat with noncalcified coronary plaque volume and with low attenuation plaque in people with HIV

OBJECTIVES

People with HIV are exposed to a higher risk of coronary artery disease (CAD) compared with the general population. Epicardial fat may play a unique role in promoting coronary atherosclerosis. We measured epicardial fat in participants living with HIV and controls and investigated its association with coronary plaque volume and low attenuation plaque, a marker of plaque vulnerability.

DESIGN

This is a cross-sectional study, nested in the Canadian HIV and Aging Cohort Study, a large prospective cohort actively following participants with HIV and controls. Participants with low/intermediate cardiovascular risk without symptoms/history of CAD were invited to undergo cardiac computed tomography (CT).

METHODS

Volume of epicardial fat, coronary plaque and low attenuation component of the plaque were measured. Association between epicardial fat, coronary plaque volume and low attenuation component was tested using adjusted regression analysis.

RESULTS

A total of 169 participants with HIV and 81 controls underwent cardiac CT. Participants with HIV had a greater epicardial fat volume compared with controls (P = 0.019). In participants with HIV, epicardial fat volume was positively associated with duration of nonnucleoside reverse transcriptase inhibitors (NNRTI) (β=2.19, P = 0.004). After adjustment for cardiovascular risk factors, epicardial fat volume was positively associated to noncalcified plaque volume [odds ratio (OR) = 1.09, P = 0.028] and to the low-attenuation plaque component portion (β=0.38, P = 0.026).

CONCLUSION

The association of epicardial fat volume to noncalcified plaque volume and to low attenuation component plaque may suggest a potential mechanism by which epicardial fat could be a silent driver of CAD in the HIV population.

Relationship of epicardial fat volume with coronary plaque characteristics, coronary artery calcification score, coronary stenosis, and CT-FFR for lesion-specific ischemia in patients with known or suspected coronary artery disease

BACKGROUND

We explored the association of epicardial fat volume (EFV) with coronary plaque characteristics, coronary artery calcification (CAC) score, coronary stenosis, lesion-specific ischemia in patients with known or suspected coronary artery disease (CAD).

METHODS

88 controls and 221 patients were analyzed in the study. High-risk plaque was defined as existing≥2 features, including positive remodeling, low attenuation, napkin-ring sign and spotty calcification. EFV, CAC score was measured. The severity of coronary stenosis was quantified using Gensini score. CT-FFR was performed in three major coronary arteries, with a threshold of ≤0.8 considered the presence of ischemia. Univariate and multivariate regression was used to evaluate the association of EFV with CAD, palque characteristics, CAC score, Gensini score, and lesion-specific ischemia derived from CT-FFR.

RESULTS

Median EFV was 104.97 cm³ (85.47-136.09) in controls and 129.28cm³ (101.19-159.44) in patients (P < 0.001). Logistic regression analysis revealed a significant association of EFV with CAD even after adjusting for confounding factors (P < 0.05). At linear regression analysis, EFV was significantly correlated with high-risk plaque and lesion-specific ischemia, but not with non-calcified plaque, mixed plaque, calcified plaque, CAC score and Gensini score (P ≥ 0.05).

CONCLUSION

We found that EFV was associated with CAD, suggesting that it may be a promising marker of CAD. EFV was also correlated with high-risk plaque and lesion-specific ischemia, indicating that EAT was likely to be involved in myocardial ischemia and had the potential to definite patients' risk profile.

Quantification of epicardial fat using non contrast cardiac CT in an HIV population: Reproducibility and association with other body fat indices

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Assessment of epicardial fat volume is highly reproducible.

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Epicardial fat volume and epicardial fat area have a good correlation to BMI.

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Epicardial fat volume correlates best with DEXA-derived total body fat and trunk fat.

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Epicardial fat volume should be considered over other CT assessment methods when quantifying epicardial fat in HIV patients.

Purpose

To assess the reproducibility of different epicardial fat measurement and their association with other adiposity measurements in HIV-infected and non-HIV-infected patients.

Methods and materials

In this cross-sectional study, 167 HIV-infected and 58 non-HIV-infected consecutive participants (200 males; mean age 56 years) with low/intermediate cardiovascular risk were recruited between 2012 and 2017 from a large prospective cohort and underwent non-contrast cardiac CT. Two independent observers measured epicardial fat volume, area and thickness in all participants. For intra-observer agreement, one observer did a second assessment in a subset of 40 patients. Agreement was assessed with the intraclass correlation coefficient (ICC). Pearson's correlation was estimated to assess the association between epicardial fat, body-mass index (BMI) and dual-energy x-ray absorptiometry (DEXA) derived percentage of body fat.

Results

Inter-observer agreement was excellent for epicardial fat volume (ICC 0.75) and area (ICC 0.95) and good for epicardial fat thickness (ICC near the left anterior descending artery (LAD) 0.64, ICC near right coronary artery (RCA) 0.64). Intra-observer agreement was excellent for epicardial fat volume (ICC 0.97), area (ICC 0.99), thickness at LAD (ICC 0.71) and good for epicardial fat thickness at RCA (ICC 0.68). Epicardial fat volume had a better correlation to total body fat (r = 0.28, p < 0.001) and trunk fat (r = 0.37, p < 0.001), in comparison to other epicardial fat indices.

Conclusion

Assessment of epicardial fat volume is highly reproducible in both HIV-infected and non-HIV-infected patients and shows a superior correlation with DEXA-based body and trunk fat measurements. Epicardial fat volume should be considered over other CT assessment methods when quantifying epicardial fat in HIV patients.

Unraveling the Role of Epicardial Adipose Tissue in Coronary Artery Disease: Partners in Crime?

The role of epicardial adipose tissue (EAT) in the pathophysiology of coronary artery disease (CAD) remains unclear. The present systematic review aimed at compiling dysregulated proteins/genes from different studies to dissect the potential role of EAT in CAD pathophysiology. Exhaustive literature research was performed using the keywords "epicardial adipose tissue and coronary artery disease", to highlight a group of proteins that were consistently regulated among all studies. Reactome, a pathway analysis database, was used to clarify the function of the selected proteins and their intertwined association. SignalP/SecretomeP was used to clarify the endocrine function of the selected proteins. Overall, 1886 proteins/genes were identified from 44 eligible studies. The proteins were separated according to the control used in each study (EAT non-CAD or subcutaneous adipose tissue (SAT) CAD) and by their regulation (up- or downregulated). Using a Venn diagram, we selected the proteins that were upregulated and downregulated (identified as 27 and 19, respectively) in EAT CAD for both comparisons. The analysis of these proteins revealed the main pathways altered in the EAT and how they could communicate with the heart, potentially contributing to CAD development. In summary, in this study, the identified dysregulated proteins highlight the importance of inflammatory processes to modulate the local environment and the progression of CAD, by cellular and metabolic adaptations of epicardial fat that facilitate the formation and progression of atherogenesis of coronaries.

Influence of EPICardial adipose tissue in HEART diseases (EPICHEART) study: Protocol for a translational study in coronary atherosclerosis

INTRODUCTION

Accumulation of epicardial adipose tissue (EAT) is associated with coronary artery disease (CAD) and increased risk of coronary events in asymptomatic subjects and low-risk patients, suggesting that EAT promotes atherosclerosis in its early stage. Recent studies have shown that the presence of CAD affects the properties of adjacent EAT, leading to dynamic changes in the molecular players involved in the interplay between EAT and the coronary arteries over the history of the disease. The role of EAT in late-stage CAD has not been investigated.

OBJECTIVES

In a comparative analysis with mediastinal and subcutaneous adipose tissue, we aim to investigate whether the volume of EAT assessed by computed tomography and its proteome assessed by SWATH-MS mass spectrometry are associated with late stages of CAD in an elderly cohort of severe aortic stenosis patients.

METHODS

The EPICHEART study (NCT03280433) is a prospective study enrolling patients with severe degenerative aortic stenosis referred for elective aortic valve replacement, whose protocol includes preoperative clinical, nutritional, echocardiographic, cardiac computed tomography and invasive coronary angiographic assessments. During cardiac surgery, samples of EAT and mediastinal and subcutaneous thoracic adipose tissue are collected for proteomics analysis by SWATH-MS. In addition, pericardial fluid and peripheral and coronary sinus blood samples are collected to identify circulating and local adipose tissue-derived biomarkers of CAD.

CONCLUSION

We designed a translational study to explore the association of EAT quantity and quality with advanced CAD. We expect to identify new biochemical factors and biomarkers in the crosstalk between EAT and the coronary arteries that are involved in the pathogenesis of late coronary atherosclerosis, especially coronary calcification, which might be translated into new therapeutic targets and imaging tools by biomedical engineering.

Effects of metformin on epicardial adipose tissue and atrial electromechanical delay of obese children with insulin resistance

INTRODUCTION

Obesity is usually related to insulin resistance and glucose metabolism disorders. The relationship between insulin resistance and epicardial adipose tissue and atrial electromechanical delay has been described in previous studies.

AIM

This study aims to demonstrate the effects of metformin on epicardial adipose tissue and electromechanical delay in patients using metformin for insulin resistance.

MATERIALS AND METHODS

A total of 30 patients using metformin for insulin resistance were included in the study. Pre-treatment and post-treatment epicardial adipose tissue and electromechanical delay were evaluated.

RESULTS

There was a statistically significant decrease in epicardial adipose tissue thickness after 3 months of metformin therapy (6.4 ± 2.1 versus 4.7 ± 2.0; p = 0.008). Furthermore, the inter-atrial and intra-atrial electromechanical delay also significantly decreased after 3 months of metformin monotherapy (23.6 ± 8.2 versus 18.1 ± 5.8; p < 0.001, 9.1 ± 2.9 versus 6.3 ± 3.6; p = 0.003, respectively).

CONCLUSION

In this study, we show that metformin monotherapy significantly decreases epicardial adipose tissue thickness and electromechanical delay in obese children.

Maternal omega-3 polyunsaturated fatty acids supplementation in pregnancy decreases MMP-1 levels in breastmilk: a cross-sectional study

INTRODUCTION

Anti-inflammatory properties of fish-oil are well known and suggested during pregnancy. MMP-1 is involved in inflammation and tissue remodelling. There have been studies focused on anti-inflammatory effect of maternal omega use on human milk while little is known about the effect of omega use on breastmilk proteases. Leptin is an important hormone that influences MMP levels in various tissues and exerts its metabolic effects. In our study we assessed the levels of MMP-1, TIMP-1, leptin, IL-6 and FA's including PUFA in breastmilk from women who used omega-3.

MATERIALS AND METHODS

Our study was a cross-sectional study included 67(Group 1, n = 32, omega user; Group 2 n = 35, non-user)lactating women and their infan MMP-1, TIMP-1, leptin, IL-6 and FA's were evaluated in breastmilk of both groups. MMP-1, TIMP-1, IL-6 and leptin were measured by enzyme-linked immunoabsorbent assay (ELISA) method. Breastmilk fatty acids were measured by gas chromatography flame ionisation detector (GC-FID).

RESULTS

Matrix metalloproteinase-1 (MMP-1) levels in breastmilk were significantly lower in breastmilk from omega users (mean ± SD, 0.455 ± 0.1) than non-users (mean ± SD, 0.677 ± 0.289) (p=.0001). MMP-1 and omega 6:3 ratio were positively correlated (r: 0.301, p=.01). MMP levels were correlated with IL-6 (Pearson's r: 0.411, p<.001). MMP-1 and leptin levels were positively correlated (r: .388, p=.001).

CONCLUSION

MMP-1 levels in breastmilk, may be modified by maternal omega use in pregnancy which may help to redirect extracellular matrix remodelling and metabolic programming in early infancy.

Osteopontin: The Molecular Bridge between Fat and Cardiac-Renal Disorders

Osteopontin (OPN) is a multifaceted matricellular protein, with well-recognized roles in both the physiological and pathological processes in the body. OPN is expressed in the main organs and cell types, in which it induces different biological actions. During physiological conditioning, OPN acts as both an intracellular protein and soluble excreted cytokine, regulating tissue remodeling and immune-infiltrate in adipose tissue the heart and the kidney. In contrast, the increased expression of OPN has been correlated with the severity of the cardiovascular and renal outcomes associated with obesity. Indeed, OPN expression is at the “cross roads” of visceral fat extension, cardiovascular diseases (CVDs) and renal disorders, in which OPN orchestrates the molecular interactions, leading to chronic low-grade inflammation. The common factor associated with OPN overexpression in adipose, cardiac and renal tissues seems attributable to the concomitant increase in visceral fat size and the increase in infiltrated OPN⁺ macrophages. This review underlines the current knowledge on the molecular interactions between obesity and the cardiac–renal disorders ruled by OPN.

Effects of valproic acid and levetiracetam monotherapy on carotid intima-media and epicardial adipose tissue thickness in non-obese children with epilepsy

OBJECTIVE

The aim of the study was to investigate the risk of subclinical atherosclerosis independent from obesity and high blood lipid levels in pediatric patients with idiopathic epilepsy receiving valproic acid or levetiracetam monotherapy by evaluating carotid intima-media thickness (CIMT) and Epicardial adipose tissue thickness (EATT).

METHODS

A total of 75 patients (38 males, 37 females; mean age 127.2 ± 37.9 months) with epilepsy receiving either valproic acid or levetiracetam monotherapy for more than 12 months (Epilepsy Group) and 75 sex, age, body mass index (BMI) matched healthy children (40 males, 35 females; mean age 133.8 ± 38.7 months) (Control Group) were included in the study. The mean duration of therapy was 27.6 ± 10.5 months. Serum lipid levels (total cholesterol, triglycerides, low density lipoprotein, high density lipoprotein) and CIMT-EATT of the patients and controls were assessed. Also, epilepsy group were divided according to antiepileptic drugs (valproic acid group and levetiracetam group).

RESULTS

The CIMT was determined as 0.6 ± 0.08 mm in epilepsy group and 0.49 ± 0.15 mm in control group (p < 0.001). The EATT was measured as 5.96 ± 0.8 mm in epilepsy group and 3.7 ± 0.5 mm in control group (p < 0.001). Of epileptic patients, 45 were using valproic acid monotherapy and 30 were on levetiracetam monotherapy. There was no significant difference in terms of CIMT between valproic acid and levetiracetam groups (0.61 ± 0.09 mm vs. 0.57 ± 0.07 mm; p = 0.07). EATT measurements were significantly higher in valproic acid group compared to levetiracetam group (6.14 ± 0.8 mm vs. 5.7 ± 0.7 mm; p = 0.02). CIMT and EATT values were not associated with the dosage and duration of each antiepileptic drug.

CONCLUSION

Non-obese children with epilepsy receiving valproic acid or levetiracetam monotherapy might have an increased risk for developing subclinical atherosclerosis despite normal lipid levels. The effect of valproic acid was more evident especially on EATT.

Validation of the echocardiographic assessment of epicardial adipose tissue thickness at the Rindfleisch fold for the prediction of coronary artery disease

BACKGROUND AND AIM

Echocardiography is a promising technique for the assessment of epicardial adipose tissue (EAT). Increased EAT thickness is associated with different cardiac diseases, including; coronary artery disease (CAD). Since several different echocardiographic approaches have been proposed to measure EAT, the identification of a standardized method is needed. We propose the assessment of EAT maximal thickness at the Rindfleisch fold, the reproducibility of this measurement and its correlation with EAT thickness and volume assessed at cardiac magnetic resonance (CMR). Finally, we will test the predictive role of this measurement on the presence of significant CAD.

METHODS AND RESULTS

In 1061 patients undergoing echocardiography, EAT thickness was measured at the level of the Rindfleisch fold. In 70 patients, we tested the relationship between echo-EAT thickness and EAT thickness and volume assessed at CMR. In 499 patients with suspected CAD, undergoing coronary artery angiography, we tested the predictive value of EAT on the presence of significant CAD. Echo-EAT thickness measurements had an excellent reliability as indicated by the inter-observer (ICC:0.97; 95% C.I. 0.96 to 0.98) and intra-observer (ICC:0.99; 95% C.I. 0.98 to 0.99) reliability rates. Echo-EAT thickness significantly correlated with CMR-EAT thickness and volume (p < 0.001). An EAT thickness value >10 mm discriminated patients with significant CAD at coronary angiography (p < 0.001). At multivariable analysis, including demographic data and cardiovascular risk factors, EAT thickness was an independent predictor of significant CAD and showed an additive predictive value over common atherosclerotic risk factors.

CONCLUSIONS

Echocardiographic assessment of EAT thickness at the level of the Rindfleisch fold represents a simple and trustworthy method. An increased EAT thickness shows an additive predictive value on CAD over common atherosclerotic risk factors, thus suggesting its potential clinical use for CAD risk stratification.

Perirenal and epicardial fat and their association with carotid intima-media thickness in children

Recent data suggest that subclinical atherosclerosis is more related to visceral adipose tissue distribution than to overall fat mass. Both perirenal fat and epicardial fat are visceral fat depots surrounding the kidneys and the myocardium, respectively, which can be easily assessed by ultrasound. Their clinical relevance in children is largely unknown. This review describes studies relating perirenal and epicardial fat to cardiovascular disease or carotid intima-media thickness (cIMT), a well-established surrogate for subclinical atherosclerosis, and discusses this in context with our own data from children. In adults, both perirenal and epicardial fat are useful biological markers of visceral obesity. The former has been related to hypertension in overweight subjects and with atherosclerosis in patients with human immunodeficiency virus. The latter was associated with several metabolic syndrome components and with calcification of the carotid artery. In healthy prepubertal children, both epicardial and perirenal fat thickness, rather than total body fat mass, were related to cIMT. Ultrasonography measures of perirenal and epicardial fat are related to atherosclerosis in adults and may be convenient tools for the assessment of cardiometabolic risk in children.

Epicardial adipose thickness in youth with type 1 diabetes

BACKGROUND AND OBJECTIVE

Epicardial adipose thickness (EAT) is increased in adults with type 1 diabetes (T1D) and is thought to contribute to cardiovascular disease (CVD) in this population. Given that CVD risk factors emerge early in life, the purpose of this study was to identify whether EAT is increased in pediatric patients with T1D compared with non-diabetic controls.

METHODS

Anthropometric data, blood pressure (BP), and EAT were evaluated in 20 youth with T1D and 20 age, sex, and body mass index (BMI) matched healthy controls between the ages of 5 and 18 years.

RESULTS

EAT was 18.5% higher among youth with T1D compared to healthy controls (1.65 ± 0.44 mm vs 1.37 ± 0.27 mm, P = .02). In the entire cohort, EAT was correlated with age (r = 0.71, P < .001), BMI (r = .69, P < .001), waist circumference (r = 0.60, P < .001), systolic BP (r = .34, P = .03), and diastolic BP (r = 0.41, P = .009). Among youth with T1D, there were no significant correlations between EAT and HbA1c (r = -0.16, P = .50), insulin dose (r = .09, P = .71), or duration of disease (r = 0.06, P = .82).

CONCLUSIONS

Youth with T1D exhibited significantly higher EAT compared to controls. Increased EAT was associated with adiposity and BP, but not duration of disease, insulin dose, or glycemic control. Increased EAT may represent a pathophysiologic mechanism leading to premature CVD in pediatric patients with T1D.

The number and phenotype of myocardial and adipose tissue CD68+ cells is associated with cardiovascular and metabolic disease in heart surgery patients

BACKGROUND AND AIMS

CD68+ cells are a potent source of inflammatory cytokines in adipose tissue and myocardium. The development of low-grade inflammation in adipose tissue is implicated in the pathogenesis of obesity-associated disorders including type 2 diabetes mellitus (T2DM) and cardiovascular disease. The main aim of the study was to characterize and quantify myocardial and adipose tissue CD68+ cells and adipose tissue crown-like structures (CLS) in patients with obesity, coronary artery disease (CAD) and T2DM.

METHODS AND RESULTS

Samples were obtained from the right atrium, epicardial (EAT) and subcutaneous adipose tissue (SAT) during elective heart surgery (non-obese, n = 34 patients; obese, n = 24 patients). Immunohistochemistry was used to visualize CD68+ cells. M1-polarized macrophages were visualized by immunohistochemical detection of CD11c. The proportion of CD68+ cells was higher in EAT than in SAT (43.4 ± 25.0 versus 32.5 ± 23.1 cells per 1 mm²; p = 0.015). Myocardial CD68+ cells were more abundant in obese patients (45.6 ± 24.5 versus 27.7 ± 14.8 cells per 1 mm²; p = 0.045). In SAT, CD68+ cells were more frequent in CAD patients (37.3 ± 23.0 versus 23.1 ± 20.9 cells per 1 mm²; p = 0.012). Patients having CLS in their SAT had higher average BMI (34.1 ± 6.4 versus 29.0 ± 4.5; p = 0.024).

CONCLUSIONS

Regional-based increases in the frequency of CD68+ cells and changes of their phenotype in CLS were detected in obese patients and CAD patients. Therapeutic modulation of adipose tissue inflammation may represent a target for treatment of obesity.

The role of perivascular adipose tissue in the development of cardiovascular diseases. The importance of diagnosis for assessing the risk stratification of cardiovascular diseases

Obesity is closely associated with metabolic and cardiovascular diseases, including dyslipidemia, coronary artery disease, hypertension, and heart failure. Adipose tissue (AT) is identified as a complex endocrine organ, with a wide range of regulatory functions at the cellular, tissue and systemic levels. Various terms, including paracardiac, epicardial and pericardial, are used to describe the fatty deposits surrounding the heart. Among all the fat depots, perivascular AT (PVAT) is of great biological significance for the cardiovascular system due to its anatomical proximity to the vessels. Recent studies have shown the presence of a complex, bidirectional paracrine and vasocardial signaling system between the vascular wall and PVAT. In the review, we will discuss the biological role of PVAT in both the physiological state and cardiovascular pathology, emphasizing its dual proatherogenic and antiatherogenic role. Let us consider PVAT as a target for various therapeutic agents in cardiovascular diseases. We will also analyze data on the role of non-invasive techniques as a diagnostic tool for assessing coronary artery inflammation.

Epicardial Adipose Tissue and Cardiovascular Disease

PURPOSE OF REVIEW

Epicardial adipose tissue has been associated with the development/progression of cardiovascular disease. We appraise the strength of the association between epicardial adipose tissue and development/progression of cardiovascular diseases like coronary artery disease, atrial fibrillation, and heart failure with preserved ejection fraction.

RECENT FINDINGS

Cross-sectional clinical and translational correlative studies have established an association between epicardial adipose tissue and progression of coronary artery disease. Recent studies question this association and underline the need for longitudinal studies. Epicardial adipose tissue also plays a definite role in the pathobiology of atrial fibrillation and its recurrence after ablation. In contrast to an early paradigm, epicardial adipose tissue does not appear to play a key role in the pathogenesis of heart failure with preserved ejection fraction in obese patients. The association of epicardial adipose tissue with atrial fibrillation is robust. In contrast, the association of epicardial adipose tissue with coronary artery disease and heart failure with preserved ejection fraction is tenuous. Additional research, including longitudinal studies, is needed to confirm or refute these proposed associations.

Behavior of Metalloproteinases in Adipose Tissue, Liver and Arterial Wall: An Update of Extracellular Matrix Remodeling

Extracellular matrix (ECM) remodeling is required for many physiological and pathological processes. Metalloproteinases (MMPs) are endopeptidases which are able to degrade different components of the ECM and nucleus matrix and to cleave numerous non-ECM proteins. Among pathological processes, MMPs are involved in adipose tissue expansion, liver fibrosis, and atherosclerotic plaque development and vulnerability. The expression and the activity of these enzymes are regulated by different hormones and growth factors, such as insulin, leptin, and adiponectin. The controversial results reported up to this moment regarding MMPs behavior in ECM biology could be consequence of the different expression patterns among species and the stage of the studied pathology. The aim of the present review was to update the knowledge of the role of MMPs and its inhibitors in ECM remodeling in high incidence pathologies such as obesity, liver fibrosis, and cardiovascular disease.

Epicardial fat thickness correlates with coronary in-stent restenosis in patients with acute myocardial infarction

OBJECTIVE

To determine the relation between epicardial fat thickness and coronary in-stent restenosis in patients with acute myocardial infarction and percutaneous coronary intervention.

METHODS

A prospective study was conducted, which included 129 patients (67.3% male, mean age 62.9±10 years) with ST segment elevation acute myocardial infarction undergoing primary percutaneous coronary intervention with bare metal stent. Patients were divided in two groups according to the presence (n=21) or not (n=108) of in-stent restenosis during one year follow-up.

RESULTS

Epicardial fat was significantly thicker in patients with coronary in-stent restenosis (5.51±1.6 vs 4.14±2.0mm, p=0.006). A proportionally and significantly thicker epicardial fat was found according to the increase in coronary disease severity (3.3±0.9mm vs 4.3±1.8mm vs 4.7±2.3mm vs 6.7±2.2mm, for type A, B1, B2 and C lesions, respectively, p=0.001) and number of vessels (3.07±1.2mm vs 4.92±1.8mm vs 5.43±2.2mm, for one, two and three vessels disease, respectively, p<0.0001). Epicardial fat thickness ≥4.7mm had 75.0% sensibility and 69.0% specificity for predicting restenosis (AUC=0.737).

CONCLUSIONS

Echocardiographic evaluation of epicardial fat thickness could identify those patients with acute myocardial infarction with greater probabilities of in-stent restenosis after percutaneous coronary intervention.

Cellular characterization of human epicardial adipose tissue: highly expressed PAPP-A regulates insulin-like growth factor I signaling in human cardiomyocytes

Little is known about the cellular biology of fat surrounding the human heart. In this study, we obtained paired samples of epicardial fat, the visceral fat depot attached to the heart, and subcutaneous skin fat from patients undergoing open heart surgery to test the hypothesis that human epicardial fat cells differentially express bioactive molecules that have the potential to affect cardiac function. First, we characterized the free fatty acids (FFAs), adipocytokines, and growth factors secreted by isolated adipocytes and preadipocytes in cell culture. There was little to distinguish the fat cell secretory products in terms of FFAs and adipocytokines. The most striking finding was that preadipocytes from epicardial adipose tissue expressed high levels of pregnancy-associated plasma protein-A (PAPP-A), a novel metalloproteinase that enhances local insulin-like growth factor (IGF) action through cleavage of inhibitory IGF binding protein-4 (IGFBP-4). PAPP-A levels were 15-fold higher in conditioned medium from epicardial preadipocytes than from subcutaneous preadipocytes (P < 0.0001). PAPP-A was not expressed in mature adipocytes. Next we determined whether PAPP-A could affect IGF-I signaling in a human cardiomyocyte cell line. IGF-I activated receptor-mediated auto-phosphorylation, and this was blocked by wild-type and protease-resistant IGFBP-4. Addition of PAPP-A induced cleavage of wild-type, but not protease-resistant, IGFBP-4 thereby restoring IGF-I action. A proteolytically defective PAPP-A had no effect. IGF-I receptor-mediated signaling through the phosphatidylinositol 3-kinase pathway was similarly inhibited by IGFBP-4 and restored by PAPP-A. Thus, human epicardial fat cells differentially express PAPP-A, which has the potential to affect IGF signaling in the heart.

Evaluation of Epicardial Fat Thickness in Young Patients With Embolic Stroke of Undetermined Source

OBJECTIVES

Epicardial adipose tissue is metabolically active and is an important predictor of metabolic and cardiovascular diseases. This study investigated the echocardiographic epicardial adipose tissue measurement in young patients with embolic stroke of undetermined source (ESUS).

MATERIALS AND METHODS

We studied 77 volunteers, including 40 patients with ESUS (mean age 43±8 y, 16 female patients) and 37 healthy subjects (mean age 38±7 y, 20 female subjects). All necessary biochemical parameters were analyzed, and epicardial fat thickness (EFT) was measured by echocardiography in all subjects. Additional related diagnostic work-up was conducted in each patient, according to the patients' clinical presentation.

RESULTS

The patients with ESUS had a significantly higher EFT than the control group (5.51±0.82 vs. 3.96±0.51; P<0.01). Furthermore, there was a positive correlation between EFT and serum C-reactive protein levels (r=0.284; P<0.05). As an optimal cut-off point, a high-risk EFT value of 4.6 mm was determined to predict ESUS, with an 87.5% sensitivity and an 81.1% specificity.

CONCLUSION

We found that echocardiographic EFT was significantly higher in young patients with ESUS than in healthy individuals. Increased EFT might be a novel risk factor in these patients.

Characterization of mouse pericardial fat: regulation by PAPP-A

Although implicated in cardiovascular disease, little is known about the fat surrounding the heart. In humans, epicardial fat is the visceral fat depot of the heart, which directly contacts the myocardium. This strategically placed fat depot is thought to produce bioactive molecules that could affect cardiac function. A major limitation in understanding the biology of epicardial fat is its restricted access in humans and its seeming absence in commonly-used experimental animal models. Although laboratory mice do not have epicardial fat per se, they do have a fat depot around the heart. In this study, we found that mouse pericardial fat has the molecular signature, small adipocyte size, and resistance to differentiation consistent with visceral fat. In addition, we show that mouse pericardial fat is regulated by pregnancy-associated plasma protein-A (PAPP-A), a key modulator of local insulin-like growth factor bioavailability. PAPP-A is highly expressed in mouse pericardial fat at levels equivalent to those in mesenteric visceral fat and 10-fold higher than in subcutaneous inguinal fat (P = .0003). Cultured pre-adipocytes isolated from pericardial fat show 2-fold increased PAPP-A secretion compared to pre-adipocytes isolated from inguinal fat. Furthermore, PAPP-A knock-out mice fed a high fat diet for 20 weeks have significantly reduced pericardial fat (by 60%; P < .0001) compared to wild-type littermates. There was no significant difference in inguinal fat between wild-type and PAPP-A knock-out mice. These data characterize a new mouse model of visceral-like pericardial fat and lay a foundation for understanding its role in human heart disease.

Is echocardiographic epicardial fat thickness increased in patients with coronary artery disease? A systematic review and meta-analysis

Background

The relation of epicardial fat thickness (EFT) to coronary artery disease (CAD) has recently been reported in multiple studies. Echocardiography is a safe and relatively inexpensive and accessible approach to assess regional EFT, which can be performed easily in many centers.

Objective

To determine the association between echocardiographic EFT and the presence or the absence of CAD.

Methods

This was a systematic review and meta-analysis conducted on literature available in electronic databases up to March 2018. The articles measuring EFT by echocardiography in the right ventricular (RV) free wall were included in the study. The quality of the enrolled items was assessed using the Methodological Index for Non-Randomized Studies (MINORS) checklist. The analyses were performed using the Comprehensive Meta-Analysis version 2 software. Cochran’s Q test and I² index were used to evaluate heterogeneity.

Results

This meta-analysis was performed on 13 studies involving 2,436 patients (1,622 with CAD, and 814 without CAD). The maximum EFT reported by echocardiography was 12.9±2.7 mm in the CAD group and 8.4±2.5 mm in the non-CAD group. The minimum EFT reported by echocardiography was 2.2±1.8 mm in the CAD group and 1.8±1.4 mm in the non-CAD group. The heterogeneity was found among the researched studies (I²=91.8%, p=0.000, Q-value=146.43, df [Q] =12) using the random effect model. The patients with CAD had a significantly higher echocardiographic EFT than those without CAD (SMD=1.03, 95% CI= 0.70–1.37, p=0.000).

Conclusion

According to the findings of this meta-analysis, the echocardiographic EFT in the subjects with CAD was significantly higher than that of those without CAD. The measurement of echocardiographic EFT seems to be an acceptable strategy for risk stratification of heart diseases considering ease of use, cost-effectiveness and non-exposure characteristics, compared to other imaging interventions.

The measurement of both carotid intima-media thickness and epicardial adipose tissue thickness in children with epilepsy receiving antiepileptic drug therapy

OBJECTIVE

The aim of this study was to evaluate the carotid intima-media thickness together with the thickness of the epicardial adipose tissue in patients receiving antiepileptic drug therapy and to investigate the presence of increased cardiovascular risk in these patients.

METHODS

The study included a total of 52 patients comprising 32 males and 20 females who were diagnosed as having epilepsy and who were using one or more antiepileptic drugs. The control group consisted of 34 healthy individuals comprising 16 males and 18 females. The individuals selected for the study group were requested to go to the hospital after overnight fasting. After blood sampling for serum lipid value, the carotid intima-media thickness was measured with high resolution B-mode ultrasonography and epicardial adipose tissue thickness with echocardiography in the patients and the control group subjects.

RESULTS

The carotid intima-media thickness was determined as 0.47 ± 0.05 mm in the patient group and 0.44 ± 0.04 mm in the control group (p = 0.028). The carotid intima-media thickness was measured as 0.45 ± 0.05 mm in patients with epilepsy taking monotherapy and 0.49 ± 0.04 mm in those taking polytherapy (p = 0.003). The epicardial adipose tissue thickness was determined as 3.42 ± 0.09 mm in the patient group and 1.72 ± 0.90 mm in the control group (p = 0.000). The epicardial adipose tissue thickness was measured as 3.16 ± 0.87 mm in patients with epilepsy taking monotherapy and 3.77 ± 0.83 mm in those taking polytherapy (p = 0.041).

CONCLUSIONS

It was determined that carotid intima-media thickness and epicardial adipose tissue thickness were significantly high in children with epilepsy taking long-term antiepileptic drugs. These results demonstrate that these patients could be at increased risk of the development of cardiovascular complications. There is a need for more extensive studies on this subject.

Epicardial adipose tissue feeding and overfeeding the heart

Epicardial adipose tissue is a particular visceral fat depot with unique anatomic, biomolecular, and genetic features. Epicardial fat displays both physiological and pathological properties. Epicardial fat expresses genes and secretes cytokines actively involved in the thermogenesis and regulation of lipid and glucose metabolism of the adjacent myocardium. A disequilibrium between epicardial fat feeding and overfeeding the myocardium with free fatty acids leads to intramyocardial fat infiltration causing organ damage and clinical consequences. The upregulation of epicardial fat proinflammatory and lipogenic genes contributes to the fat build up in the proximal coronary arteries. Epicardial fat is a measurable and modifiable risk factor that can serve as a novel and additional tool for cardiovascular risk stratification. Pharmacologically targeting epicardial fat with drugs such as glucagon peptide-like 1 analogs or sodium glucose transport 2 inhibitors reduces the epicardial fat burden and induces beneficial cardiometabolic effects. Assessment and manipulation of epicardial fat transcriptome might open new avenues in the prevention of cardiometabolic diseases.

Perivascular adipose tissue and coronary atherosclerosis

Adipose tissue (AT) is no longer viewed as a passive, energy-storing depot, and a growing body of evidence supports the concept that both quantitative and qualitative aspects of AT are critical in determining an individual's cardiometabolic risk profile. Among all AT sites, perivascular AT (PVAT) has emerged as a depot with a distinctive biological significance in cardiovascular disease given its close anatomical proximity to the vasculature. Recent studies have suggested the presence of complex, bidirectional paracrine and vasocrine signalling pathways between the vascular wall and its PVAT, with far-reaching implications in cardiovascular diagnostics and therapeutics. In this review, we first discuss the biological role of PVAT in both cardiovascular health and disease, highlighting its dual pro-atherogenic and anti-atherogenic roles, as well as potential therapeutic targets in cardiovascular disease. We then review current evidence and promising new modalities on the non-invasive imaging of epicardial AT and PVAT. Specifically, we present how our expanding knowledge on the bidirectional interplay between the vascular wall and its PVAT can be translated into novel clinical diagnostics tools to assess coronary inflammation. To this end, we present the example of a new CT-based method that tracks spatial changes in PVAT phenotype to extract information about the inflammatory status of the adjacent vasculature, highlighting the numerous diagnostic and therapeutic opportunities that arise from our increased understanding of PVAT biology.

Epicardial fat thickness can predict severity and multivessel distribution in Egyptian patients with atherosclerotic coronary artery stenosis

Background

Epicardial fat, in addition to its secretory function, may have an important role in predicting and stratifying cardiovascular risk. There is a paucity of data regarding correlation between epicardial fat thickness and coronary artery disease in Egypt.

Aim of the study

To study the relationship between epicardial fat thickness (EFT) measured by trans-thoracic echocardiography (TTE) and severity of coronary artery disease (CAD) and its distribution in Egyptian population.

Methods

Our study was a prospective observational case control study that was conducted upon 150 patients with stable CAD presented to the cardiology departments in Ain Shams University hospitals and Al-Zaitoun Specialized hospital from March to October, 2015. EFT was measured by TTE for all patients at the same day of performing invasive coronary angiography (CA). We studied the statistical correlation between EFT and presence of CAD, also we tried to find if EFT is related to severity of CAD (according to Gensini score) or its distribution.

Results

The study population was divided according to CA results to 2 groups; patients’ group having atherosclerotic CAD consisting of 100 patients and control group consisting of 50 patients with normal coronaries. All the well- known risk factors of CAD (male sex, smoking, hypertension, diabetes, dyslipidemia, increased body mass index) were significantly more prevalent in the patients’ group. Patients had significantly lower systolic and diastolic functions. EFT was significantly correlated to presence of CAD (P < 0.001) with a cut-off value of 5.5 mm. EFT was significantly correlated to severity of CAD assessed by Gensini score (P < 0.001). Also we found a significant positive correlation between EFT and number of vessels affected (P <  0.001).

Conclusion

EFT is a good predictor of CAD severity and multivessel affection in Egyptian patients. It is also a potentially promising predictor for the presence of CAD.

Sleep-disordered breathing and epicardial adipose tissue in patients with heart failure

BACKGROUND AND AIMS

Sleep-disordered breathing (SDB) is common in patients with heart failure (HF), contributes to the progression of cardiac disease, and is associated with adverse prognosis. Previous evidence indicates that epicardial adipose tissue (EAT) is independently associated with sleep apnea in obese individuals. We explored the relationship between SDB and EAT in HF patients.

METHODS AND RESULTS

EAT thickness was assessed by echocardiography in 66 patients with systolic HF undergoing nocturnal cardiorespiratory monitoring. A significantly higher EAT thickness was found in patients with SDB than in those without SDB (10.7 ± 2.8 mm vs. 8.3 ± 1.8 mm; p = 0.001). Among SDB patients, higher EAT thickness was found in both those with prevalent obstructive sleep apnea (OSA) and those with prevalent central sleep apnea (CSA). Of interest, EAT thickness was significantly higher in CSA than in OSA patients (11.9 ± 2.9 vs. 10.1 ± 2.5 p = 0.022). Circulating plasma norepinephrine levels were higher in CSA than in OSA patients (2.19 ± 1.25 vs. 1.22 ± 0.92 ng/ml, p = 0.019). According to the apnea-hypopnea index (AHI), patients were then stratified in three groups of SDB severity: Group 1, mild SDB; Group 2, moderate SDB; Group 3, severe SDB. EAT thickness progressively and significantly increased from Group 1 to Group 3 (ANOVA p < 0.001). At univariate analysis, only left ventricular ejection fraction and AHI significantly correlated with EAT (p = 0.019 and p < 0.0001, respectively). At multivariate analysis, AHI was the only independent predictor of EAT (β = 0.552, p < 0.001).

CONCLUSIONS

Our results suggest an association between the presence and severity of sleep apneas and cardiac visceral adiposity in HF patients.

Machine learning in the prediction of cardiac epicardial and mediastinal fat volumes

We propose a methodology to predict the cardiac epicardial and mediastinal fat volumes in computed tomography images using regression algorithms. The obtained results indicate that it is feasible to predict these fats with a high degree of correlation, thus alleviating the requirement for manual or automatic segmentation of both fat volumes. Instead, segmenting just one of them suffices, while the volume of the other may be predicted fairly precisely. The correlation coefficient obtained by the Rotation Forest algorithm using MLP Regressor for predicting the mediastinal fat based on the epicardial fat was 0.9876, with a relative absolute error of 14.4% and a root relative squared error of 15.7%. The best correlation coefficient obtained in the prediction of the epicardial fat based on the mediastinal was 0.9683 with a relative absolute error of 19.6% and a relative squared error of 24.9%. Moreover, we analysed the feasibility of using linear regressors, which provide an intuitive interpretation of the underlying approximations. In this case, the obtained correlation coefficient was 0.9534 for predicting the mediastinal fat based on the epicardial, with a relative absolute error of 31.6% and a root relative squared error of 30.1%. On the prediction of the epicardial fat based on the mediastinal fat, the correlation coefficient was 0.8531, with a relative absolute error of 50.43% and a root relative squared error of 52.06%. In summary, it is possible to speed up general medical analyses and some segmentation and quantification methods that are currently employed in the state-of-the-art by using this prediction approach, which consequently reduces costs and therefore enables preventive treatments that may lead to a reduction of health problems.

Liraglutide causes large and rapid epicardial fat reduction

OBJECTIVE

Epicardial adipose tissue (EAT), the visceral fat depot of the heart, is a modifiable cardiovascular risk factor and emerging therapeutic target. Liraglutide, an analog of glucagon-like peptide-1, is indicated for the treatment of type 2 diabetes mellitus. Liraglutide has recently been shown to reduce cardiovascular risk. Nevertheless, whether liraglutide could reduce EAT is unknown.

METHODS

To test the hypothesis, a 6-month randomized, open-label, controlled study was performed in 95 type 2 diabetic subjects with body mass index (BMI) ≥27 kg/m² and hemoglobinA1c ≤8% on metformin monotherapy. Individuals were randomized in two groups to receive additional liraglutide up to 1.8 mg s.c. once daily (n = 54) or to remain on metformin up to 1,000 mg twice daily (n = 41). Ultrasound-measured EAT thickness was measured at baseline and at 3- and 6-month follow-ups.

RESULTS

In the liraglutide group, EAT decreased from 9.6 ± 2 to 6.8 ± 1.5 and 6.2 ± 1.5 mm (P < 0.001), accounting for a -29% and -36% of reduction at 3 and 6 months, respectively, whereas there was no EAT reduction in the metformin group; BMI and hemoglobinA1c improved only in the liraglutide group after 6 months.

CONCLUSIONS

Liraglutide causes a substantial and rapid EAT reduction. Liraglutide cardiometabolic effects may be EAT-mediated.

Assosiation of Epicardial and Pericardial Fat Thickness with Coronary Artery Disease

INTRODUCTION

Visceral adipose tissue is a known important risk factor for coronary artery disease (CAD). While some studies have suggested relationship between epicardial fat thickness (EFT) and CAD, there are no adequate studies for pericardial fat thickness (PFT). The aim of this study was to determine the association of EFT and PFT with CAD.

METHODS

This cross-sectional study was conducted on patients who were candidates for elective coronary artery angiography, referred to Emam Reza Hospital, Mashhad, Iran during Jan 2014-2016. Demographic and laboratory data were collected. Transthoracic echocardiography was performed to determine average EFT and PFT at the standard parasternal long-axis view at end-systole for 3 cardiac cycles. SCA was performed on the same day. The patients were divided into two groups: CAD (n=59) and non-CAD (n=41) based on presence or absence of epicardial coronary artery stenosis of > 50%. Chi-square, independent T-test, and receiver operating characteristic (ROC) curve were used by SPSS Version 16 for data analysis.

RESULTS

One hundred patients (44 women and 56 men) with an average age of 56.4 ± 9.9 years were studied. The two groups were not significantly different in demographic profile and cronary risk factors. While PFT was not significantly different between the two groups, EFT was significantly higher in CAD group (3.0 ± 3.69 vs. 1.2 ± 3.6, p <0.0001). Moreover, with the increase of the affected coronary arteries, EFT increased (p <0.0001). Gensini score had a strong correlation with amount of EFT (r = 0.765, p <0.0001). EFT with a cutoff value of 4.25 mm (sensitivity=79%, specificity=68%) was specified in predicting CAD.

CONCLUSION

EFT measured by echocardiography can be used as an independent marker to predict CAD. More studies are needed to determine the predictive role of PFT for CAD.

Increased Epicardial Fat Thickness Correlates with Aortic Stiffness and N-Terminal Pro-Brain Natriuretic Peptide Levels in Acute Ischemic Stroke Patients

Epicardial fat, a metabolically active tissue, has emerged as a risk factor and active player in metabolic and cardiovascular diseases. We investigated epicardial fat thickness in patients who had sustained an acute ischemic stroke, and we evaluated the relationship of epicardial fat thickness with other prognostic factors. We enrolled 61 consecutive patients (age, ≥18 yr) who had sustained a first acute ischemic stroke and had been admitted to our hospital within 24 hours of the onset of stroke symptoms. The control group comprised 82 consecutive sex- and age-matched patients free of past or current stroke who had been admitted to our cardiology clinics. Blood samples were taken for measurement of N-terminal pro-brain natriuretic peptide (NT-proBNP) levels at admission. Aortic stiffness indices and epicardial fat thickness were measured by means of transthoracic echocardiography within the first 48 hours. In comparison with the control group, the patients with acute ischemic stroke had significantly higher epicardial fat thickness (4.8 ± 0.9 vs 3.8 ± 0.7 mm; P <0.001), lower aortic distensibility (2.5 ± 0.8 vs 3.4 ± 0.9 cm(2) ·dyn(-1); P <0.001) and lower aortic strain (5.5% ± 1.9% vs 6.4% ± 1.8%; P=0.003). We found a significant association between epicardial fat thickness, NT-proBNP levels, and arterial dysfunction in patients who had sustained acute ischemic stroke. Increased epicardial fat thickness might be a novel risk factor and might enable evaluation of subclinical target-organ damage in these patients.

Inhibition of Notch rescues the angiogenic potential impaired by cardiovascular risk factors in epicardial adipose stem cells

The epicardial adipose tissue (EAT) is a reservoir of adipose-derived stem cells (ASCs), with as yet unknown effects on myocardial and coronary arteries homeostasis. The purpose of this study was to investigate the angiogenic function of epicardial ASCs and their regulation by the common cardiovascular risk factors (CVRFs) affecting heart disease. Epicardial fat was obtained from a rodent model with clustering of CVRFs [Zucker diabetic fatty (ZDF)-Lepr(fa)] rats and from their lean control (ZDF-Crl) littermates without CVRFs, ASCs were isolated, and their function was assessed by proliferation and differentiation assays, flow cytometry, gene expression, and in vivo Matrigel angiogenesis analysis. Epicardial ASCs from both groups showed adipogenic and osteogenic differentiation capacity; however, epicardial ASCs from CVRF animals had a lesser ability to form tubular structures in vitro after endothelial differentiation, as well as a reduced angiogenic potential in vivo compared to control animals. Epicardial ASCs from CVRF rats showed up-regulation of the downstream Notch signaling genes Hes7, Hey1, and Heyl compared with control animals. The inhibition of Notch signaling by conditioning epicardial ASCs from CVRF animals with a γ-secretase inhibitor induced a reduction in Hes/Hey gene expression and rescued their angiogenic function in vivo We report for the first time the impact of CVRF burden on the ASCs of EAT and that the defective function is in part caused by increased Notch signaling. Conditioning ASCs by blocking Notch signaling rescues their angiogenic potential.-Bejar, M. T., Ferrer-Lorente, R., Peña, E., Badimon, L. Inhibition of Notch rescues the angiogenic potential impaired by cardiovascular risk factors in epicardial adipose stem cells.

Effect of sitagliptin on epicardial fat thickness in subjects with type 2 diabetes and obesity: a pilot study

The aim of the study was to assess the effect of sitagliptin addition on the epicardial adipose tissue (EAT) thickness in subjects with type 2 diabetes mellitus inadequately controlled on metformin monotherapy. This was a 24-week interventional pilot study in 26 consecutive type 2 diabetic patients, 14 females and 12 males average age of 43.8 ± 9.0 years, with Hemoglobin A1c (HbA1c) ≥ 7% on metformin monotherapy. Subjects who met the inclusion criteria were added on sitagliptin and started on sitagliptin/metformin combination at the dosage of 50 mg/1000 mg twice daily. EAT and visceral and total body fat were measured, respectively, with echocardiography and bioelectrical impedance analysis at baseline and after 24 weeks of sitagliptin/metformin treatment in each subject. HbA1c and plasma lipids were also measured. EAT decreased significantly from 9.98 ± 2.63 to 8.10 ± 2.11 mm, p = 0.001, accounting for a percentage of reduction (∆%) of -15% after 24 weeks of sitagliptin addition, whereas total body fat percentage, visceral fat, and body mass index (BMI), decreased by 8, 12, and 7%, respectively (p = 0.001 for all). After 6 month, EAT ∆% was significantly correlated with ∆% of visceral fat (r = 0.456; p = 0.01), whereas no correlation with either BMI ∆% (r = 0.292; p = 0.147) or HbA1c ∆% was found. The addition of Sitagliptin produced a significant and rapid reduction of EAT, marker of organ-specific visceral fat, in overweight/obese individuals with type 2 diabetes inadequately controlled on metformin monotherapy. EAT as measured with ultrasound can serve as no invasive and accurate marker of visceral fat changes during pharmaceutical interventions targeting the fat.

Epicardial fat: a new cardiovascular therapeutic target

Epicardial fat is the visceral fat depot of the heart. Given its rapid metabolism, organ fat specificity and simple objective measurability, epicardial fat can serve as target for pharmaceutical agents targeting the adipose tissue. Epicardial fat has shown to significantly respond to thiazolidinediones, glucagon like peptide 1 receptor agonists, dipeptidyl peptidase-4 inhibitors and statins. Epicardial fat may represent a measurable risk factor and modifiable therapeutic target. Targeted pharmaceutical interventions may allow the epicardial fat to resume its physiological role. A drug-induced browning effect on epicardial fat suggests the development of pharmacological strategies to increase energy consumption. The potential of modulating the epicardial fat transcriptome with targeted pharmacological agents can open new avenues in the pharmacotherapy of cardio-metabolic diseases.

Subclinical atherosclerosis is associated with Epicardial Fat Thickness and hepatic steatosis in the general population

BACKGROUND AND AIMS

Abdominal obesity and hepatic steatosis are ectopic fat depots associated with Metabolic Syndrome (MetS). Epicardial Fat Thickness (EFT) is a newly discovered one, increasing with obesity, insulin resistance and MetS. Therefore we studied whether different ectopic fat markers, and EFT in particular, are associated with MetS and markers of subclinical cardiovascular disease.

METHODS AND RESULTS

868 subjects from the PLIC Study were included, EFT, aortic calcifications, carotid Intima-Media Thickness (c-IMT) and echocardiographic parameters were determined by ultrasound; extra-cardiac atherosclerotic lesions were defined in presence of plaques at both carotid and aortic levels. Hepatic steatosis degrees were defined according to a scoring system. Abdominal adiposity was determined using Dual X-ray Absorbimetry (DEXA). Independently from age, women showed higher EFT versus men (4.5 (0.20-9.00) mm vs 4.00 (0.10-8.00) mm, p = 0.013); EFT was thicker in post-menopausal women (independently from hormone-replacement therapy). EFT, liver steatosis and abdominal adiposity increased with MetS (p < 0.001). EFT was the only ectopic fat marker associated with cardiac dysfunction (OR = 1.340 [1.088-1.651 95% C.I., p = 0.006); liver steatosis and EFT were associated with extra-cardiac plaques (OR = 2.529 [1.328-4.819] 95% C.I., p < 0.001 and OR = 1.195 [1.008-1.299] 95% C.I., p = 0.042; respectively). On top of cardiovascular risk factors, only EFT improved the discrimination of subjects with cardiac dysfunction and atherosclerotic plaques.

CONCLUSIONS

EFT is associated with left ventricular dysfunction and subclinical atherosclerosis. Our data suggest that EFT may represent an additional tool for the stratification of cardiovascular risk.