Diverse Adiposity and Atrio-Ventricular Dysfunction across Obesity Phenotypes: Implication of Epicardial Fat Analysis

Differences in the levels of inflammatory markers between metabolically healthy obese and other obesity phenotypes in adults: A systematic review and meta-analysis

AIMS

The aim of this study was to systematically review and analyze differences in the levels of C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) comparing metabolically healthy but obese (MHO) with metabolically healthy non-obese (MHNO), metabolically unhealthy non-obese (MUNO), and metabolically unhealthy obese (MUO) subjects.

DATA SYNTHESIS

We searched PubMed, Embase, Web of Science, and Scopus for studies that matched the relevant search terms. Differences in inflammatory marker levels between MHO and the other three phenotypes were pooled as standardized mean differences (SMD) or differences of medians (DM) using a random-effects model. We included 91 studies reporting data on 435,007 individuals. The CRP levels were higher in MHO than in MHNO subjects (SMD = 0.63, 95% CI: 0.49, 0.76; DM = 0.83 mg/L, 95% CI: 0.56, 1.11). The CRP levels were higher in MHO than in MUNO subjects (SMD = 0.16, 95% CI: 0.05, 0.28; DM = 0.39 mg/L, 95% CI: 0.09, 0.69). The CRP levels were lower in MHO than in MUO individuals (SMD = -0.43, 95% CI: -0.54, -0.31; DM = -0.82 mg/L, 95% CI: -1.16, -0.48). The IL-6 levels in MHO were higher than in MHNO while lower than in MUO subjects. The TNF-α levels in MHO were higher than in MHNO individuals.

CONCLUSIONS

This review provides evidence that CRP levels in MHO are higher than in MHNO and MUNO subjects but lower than in MUO individuals. Additionally, IL-6 levels in MHO are higher than in MHNO but lower than in MUO subjects, and TNF-α levels in MHO are higher than in MHNO individuals.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO number: CRD42021234948.

The effects of obesity on longitudinal ventricular and atrial strain in a rural population of Spanish children and adolescents, evaluated by a new strain software

BACKGROUND AND OBJECTIVES

Research on the relationship between body mass index (BMI) and strain values in children and adolescents is limited. Our aim was to analyse the relationship between BMI and strain values of both ventricles and left atrium in children and adolescents.

METHODS

Both ventricles and left atrial strain values were compared among different BMI categories in children and adolescents from a town in the South of Spain.

RESULTS

Of the 198 subjects, aged 6-17 years, 53% were of normal weight, 26% were overweight and 21% had obesity. Lower absolute values of left ventricular global longitudinal strain (25.9 ± 2.0% vs. 26.9 ± 2.2%, p = 0.002) and right ventricular free wall longitudinal strain (29.5 ± 4.2% vs. 30.8 ± 4.5%, p = 0.04) were found in subjects with obesity and overweight versus subjects with normal weight. A lower right ventricular four-chamber longitudinal strain was also observed in males with obesity and overweight (24.8 ± 3.3% vs. 26.4 ± 3.6%, p = 0.03). Statistically significant negative correlations of BMI were found for all ventricular, but not atrial, strain values in univariate analysis. This association turned non-significant for right ventricular four-chamber longitudinal strain in multivariate analysis.

CONCLUSIONS

Utilizing this new strain software, children and adolescents with high BMI were associated with significantly lower values for left and right ventricular free wall longitudinal strain, without impact in left atrial strain.

Correlation analysis of the abdominal visceral fat area with the structure and function of the heart and liver in obesity: a prospective magnetic resonance imaging study

BACKGROUND

The differences in fat deposition sites exhibit varying degrees of systemic inflammatory responses and organ damage, especially in obese individuals with excessive visceral fat. Visceral fat, which is closely related to an increase in mortality rates related to heart and liver diseases. However, few studies have analysed the differences in heart and liver indicators and their correlation among groups based on the abdominal visceral fat area (AVFA).

OBJECTIVE

Clarifying the differences in and correlations of heart and liver indicators among groups with different severities of AVFA by magnetic resonance imaging (MRI).

METHODS

Sixty-nine subjects with obesity were enrolled. The study group consisted of forty-one individuals (AVFA ≥ 150 cm2), and the control group consisted of twenty-eight individuals (100 cm2 ≤ AVFA < 150 cm2). The differences in and correlations between clinical, laboratory, and MRI indicators of the heart and liver between the two groups were analysed.

RESULTS

In the study group, the incidences of type 2 diabetes mellitus (T2DM) and insulin resistance were higher, and liver function indicators were worse. The left ventricular eccentricity ratio (LVER), left ventricular mass (LVM) and global peak wall thickness (GPWT) were higher in the study group than in the control group (P = 0.002, P = 0.001, P = 0.03), and the left ventricle global longitudinal strain (LVGLS) was lower in the study group than in the control group (P = 0.016). The pericardiac adipose tissue volume (PATV) and myocardial proton density fat fraction (M-PDFF) were higher in the study group than in the control group (P = 0.001, P = 0.001). The hepatic proton density fat fraction (H-PDFF) and abdominal subcutaneous fat area (ASFA) were higher in the study group than in the control group (P < 0.001, P = 0.012). There was a moderate positive correlation (ρ = 0.39-0.59, P < 0.001) between the AVFA and LVER, LVM, GPWT, LVGLS, and H-PDFF. There was no difference in right ventricular and most left ventricular systolic and diastolic function between the two groups.

CONCLUSION

The high AVFA group had a larger LVM, GPWT and PATV, more obvious changes in LVER, impaired left ventricular diastolic function, an increased risk of heart disease, and more severe hepatic fat deposition and liver injury. Therefore, there is a correlation between the amount of visceral adipose tissue and subclinical cardiac changes and liver injury.

Association of Non-Alcoholic Fatty Liver Disease and Hepatic Fibrosis with Epicardial Adipose Tissue Volume and Atrial Deformation Mechanics in a Large Asian Population Free from Clinical Heart Failure

Non-alcoholic fatty liver disease (NAFLD) and cardiovascular disease share several cardiometabolic risk factors. Excessive visceral fat can manifest as ectopic fat depots over vital organs, such as the heart and liver. This study assessed the associations of NAFLD and liver fibrosis with cardiac structural and functional disturbances. We assessed 2161 participants using ultrasound, and categorized them as per the NAFLD Fibrosis Score into three groups: (1) non-fatty liver; (2) fatty liver with low fibrosis score; and (3) fatty liver with high fibrosis score. Epicardial fat volume (EFV) was measured through multidetector computed tomography. All participants underwent echocardiographic study, including tissue Doppler-based E/e’ ratio and speckle tracking-based left ventricular global longitudinal strain, peak atrial longitudinal strain (PALS), and atrial longitudinal strain rates during systolic, early and late-diastolic phases (ALSRsyst, ALSRearly. ALSRlate). Larger EFV, decreased e’ velocity, PALS, ALSRsyst, and ALSRearly, along with elevated E/e’ ratio, were seen in all groups, especially in those with high fibrosis scores. After multivariate adjustment for traditional risk factors and EFV, fibrosis scores remained significantly associated with elevated E/e’ ratio, LA stiffness, and decreased PALS (β: 0.06, 1.4, −0.01, all p < 0.05). Thus, NAFLD is associated with LV diastolic dysfunction and subclinical changes in LA contractile mechanics.

Posterior left atrial epicardial adipose tissue: scope of the problem and impact of new technology

PURPOSE OF REVIEW

Patients with persistent forms of atrial fibrillation are seeking treatments based on the promise of better restoration of sinus rhythm with newer therapies. Successful catheter ablation and maintenance of atrial fibrillation in this subgroup is negatively impacted by the presence of epicardial adipose tissue (EAT) associated with the posterior left atrium.

RECENT FINDINGS

EAT is now understood to be hormonally active and promotes adverse atrial remodelling, including fibrosis and myopathy. Despite being dominantly adipose tissue, it is known to be electrically active, comprising ganglia, neural tissue and ectopic atrial myocardium that may contribute to endo-epicardial dissociation and persistent electrical activity and atrial fibrillation despite good endocardial electrical silencing. Hybrid procedures that include direct epicardial ablation of the posterior wall, including the EAT, are associated with superior outcomes in nonparoxysmal atrial fibrillation.

SUMMARY

Therapies for persistent atrial fibrillation that also ablate the EAT as part of a well tolerated transmural posterior wall ablation may improve outcomes in this challenging subset of patients.