Epicardial fat accumulation is an independent marker of impaired heart rate recovery in obese patients with obstructive sleep apnea

Dual role for angiotensin-converting enzyme 2 in Severe Acute Respiratory Syndrome Coronavirus 2 infection and cardiac fat

Angiotensin-converting enzyme 2 (ACE2) has been an increasingly prevalent target for investigation since its discovery 20 years ago. The finding that it serves a counterregulatory function within the traditional renin-angiotensin system, implicating it in cardiometabolic health, has increased its clinical relevance. Focus on ACE2's role in cardiometabolic health has largely centered on its apparent functions in the context of obesity. Interest in ACE2 has become even greater with the discovery that it serves as the cell receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), opening up numerous mechanisms for deleterious effects of infection. The proliferation of ACE2 within the literature coupled with its dual role in SARS-CoV-2 infection and obesity necessitates review of the current understanding of ACE2's physiological, pathophysiological, and potential therapeutic functions. This review highlights the roles of ACE2 in cardiac dysfunction and obesity, with focus on epicardial adipose tissue, to reconcile the data in the context of SARS-CoV-2 infection.

Cardiac Adiposity and Arrhythmias: The Role of Imaging

Increased cardiac fat depots are metabolically active tissues that have a pronounced pro-inflammatory nature. Increasing evidence supports a potential role of cardiac adiposity as a determinant of the substrate of atrial fibrillation and ventricular arrhythmias. The underlying mechanism appears to be multifactorial with local inflammation, fibrosis, adipocyte infiltration, electrical remodeling, autonomic nervous system modulation, oxidative stress and gene expression playing interrelating roles. Current imaging modalities, such as echocardiography, computed tomography and cardiac magnetic resonance, have provided valuable insight into the relationship between cardiac adiposity and arrhythmogenesis, in order to better understand the pathophysiology and improve risk prediction of the patients, over the presence of obesity and traditional risk factors. However, at present, given the insufficient data for the additive value of imaging biomarkers on commonly used risk algorithms, the use of different screening modalities currently is indicated for personalized risk stratification and prognostication in this setting.

Epicardial adipose tissue predicted prolonged QTc interval in patients with arterial hypertension

Introduction: It is important to identify those at higher risk for ventricular arrhythmia among hypertensive patients. Epicardial adipose tissue (EAT) leads to electromechanical changes in the heart by endocrine and paracrine effects with cytokines and mediators. Higher amount of EAT carries the risk of QT prolongation. Therefore, we investigated the association between EAT thickness and QTc interval in patients with arterial hypertension. Methods: A total of 230 patients who previously diagnosed with arterial hypertension between February 2019 to March 2020 were included in the study. Patients with atrial fibrillation, U-wave, atrioventricular block, left anterior or posterior fascicular block, right bundle branch block, left bundle branch block, and taking QT-prolonging medication were excluded. The corrected QT (QTc) interval was calculated with Bazzet's formula following the calculated QT interval in the semi-automatic application tool. EAT was measured at the point on the free wall of the right ventricle using transthoracic echocardiography. Results: The mean age was 62.1 ± 11.4 years and 95 (41.3%) of the patients were male. QTc was over 450 ms were considered as the prolonged interval. Both groups were similar in terms of age (p = .862), gender (p = .265) and other demographic characteristics. Left ventricle mass index (LVMI) (82.5 ± 29.5 vs 91.9 ± 32.6 g/1.7.m², p = .051) and EAT thickness (5.3 ± 2.3 vs 6.6 ± 2.6 mm, p = .001) were higher in the prolonged QTc group. Serum potassium (K) level was lesser in the prolonged QTc group (4.2 ± 0.39 vs 4.1 ± 0.4 mmol/mL, p = .005). Multivariate Cox regression analysis revealed that EAT thickness [OR = 1.227, 95% CI: 1.081-1.393, p = .002] and serum K level [OR = 0.348, 95% CI: 0.157-0.772, p = .009] predicted the prolonged QTc interval, independently. Conclusion: EAT thickness predicted prolonged QTc interval in patients with arterial hypertension. Patients with higher amount of EAT should be followed by closely monitoring to prevent arrhythmic events that may develop in the future. In addition, medications that have a potential effect on QTc interval prolongation may be carefully used in patients with higher EAT thickness.

Epicardial Adipose Tissue in Patients with Obstructive Sleep Apnea: A Systematic Review and Meta-analysis

Objective: Epicardial adipose tissue (EAT) is a potential risk factor for obstructive sleep apnea (OSA). We performed a meta-analysis to assess the association of EAT with OSA.Methods: The PubMed, EMBASE, Web of Science, Cochrane Library, and Wanfang databases were searched by two independent investigators for all observational studies assessing the association of EAT with OSA. Then we assessed the association of EAT thickness (EAT-t) and EAT volume (EAT-v) with OSA by a meta-analysis.Results: Ten studies were included in the final analysis. Compared with that in controls, EAT-t in OSA patients was significantly increased (standardized mean difference 0.88, 95% confidence interval 0.72‐1.05, P=0.000). Furthermore, EAT-t was greater in OSA patients than in controls with similar BMIs. However, we did not find significant differences in EAT-v between OSA patients and controls (standardized mean difference 2.46, 95% confidence interval −0.36 to 5.29, P=0.088). EAT-t in the mild, moderate, and severe OSA subgroups was greater than in the controls. In addition, there were significant differences in EAT-t among the mild, moderate, and severe OSA subgroups.Conclusions: EAT-t was greater in patients with OSA than in controls, and EAT-t was also associated with the severity of OSA. These findings may provide a new clue for the pathogenesis and treatment of OSA.

NAFLD and cardiovascular diseases: a clinical review

Non-alcoholic fatty liver DISEASE (NAFLD) is the most common chronic liver disease in Western countries and affects approximately 25% of the adult population. Since NAFLD is frequently associated with further metabolic comorbidities such as obesity, type 2 diabetes mellitus, or dyslipidemia, it is generally considered as the hepatic manifestation of the metabolic syndrome. In addition to its potential to cause liver-related morbidity and mortality, NAFLD is also associated with subclinical and clinical cardiovascular disease (CVD). Growing evidence indicates that patients with NAFLD are at substantial risk for the development of hypertension, coronary heart disease, cardiomyopathy, and cardiac arrhythmias, which clinically result in increased cardiovascular morbidity and mortality. The natural history of NAFLD is variable and the vast majority of patients will not progress from simple steatosis to fibrosis and end stage liver disease. However, patients with progressive forms of NAFLD, including non-alcoholic steatohepatitis (NASH) and/or advanced fibrosis, as well as NAFLD patients with concomitant types 2 diabetes are at highest risk for CVD. This review describes the underlying pathophysiological mechanisms linking NAFLD and CVD, discusses the role of NAFLD as a metabolic dysfunction associated cardiovascular risk factor, and focuses on common cardiovascular manifestations in NAFLD patients.

Association of epicardial adipose tissues with obstructive sleep apnea and its severity: A meta-analysis study

BACKGROUND AND AIMS

Obstructive sleep apnea (OSA) is a global disease that is a manifestation of metabolic syndrome. Epicardial adipose tissue (EAT), a special type of visceral adipose tissue, has been proposed to be an independent predictor of visceral adiposity. Both OSA and EAT have a close association with diabetes and coronary artery disease. Whether EAT thickness is associated with OSA is controversial.

METHODS AND RESULTS

Several databases were searched from their inception to October 13, 2019. We estimated the summarized weighted mean difference (WMD) with 95% confidence intervals (CIs) for EAT thickness in the OSA and non-OSA groups. Then, we conducted a meta-analysis to evaluate the association between EAT thickness and OSA. The relationship between EAT thickness and OSA severity was also assessed. Nine studies with a total of 1178 participants were included. Globally, patients with OSA had a higher EAT thickness than patients without OSA (WMD = 0.95, 95% CI: 0.73-1.16, P < 0.001). Compared to the non-OSA patients, those with mild, moderate, and severe OSA had a progressively higher EAT thickness (WMD = 0.62, 95% CI: 0.41-0.83; WMD = 0.83, 95% CI: 0.50-1.15; and WMD = 1.06, 95% CI: 0.70-1.43, respectively; all P < 0.001).

CONCLUSION

EAT thickness was shown to be higher in patients with OSA than in patients with non-OSA measured by echocardiography. The increase in the EAT thickness was associated with OSA severity.

Nonalcoholic fatty liver disease and cardiovascular disease phenotypes

Nonalcoholic fatty liver disease is increasingly recognized as a major global health problem. Intertwined with diabetes, metabolic syndrome, and obesity, nonalcoholic fatty liver disease embraces a spectrum of liver conditions spanning from steatosis to inflammation, fibrosis, and liver failure. Compared with the general population, the prevalence of cardiovascular disease is higher among nonalcoholic fatty liver disease patients, in whom comprehensive cardiovascular risk assessment is highly desirable. Preclinical effects of nonalcoholic fatty liver disease on the heart include both metabolic and structural changes eventually preceding overt myocardial dysfunction. Particularly, nonalcoholic fatty liver disease is associated with enhanced atherosclerosis, heart muscle disease, valvular heart disease, and arrhythmias, with endothelial dysfunction, inflammation, metabolic dysregulation, and oxidative stress playing in the background. In this topical review, we aimed to summarize current evidence on the epidemiology of nonalcoholic fatty liver disease, discuss the pathophysiological links between nonalcoholic fatty liver disease and cardiovascular disease, illustrate nonalcoholic fatty liver disease-related cardiovascular phenotypes, and finally provide a glimpse on the relationship between nonalcoholic fatty liver disease and cardiac steatosis, mitochondrial (dys)function, and cardiovascular autonomic dysfunction.