Cardiac steatosis and left ventricular function in men with metabolic syndrome

Abstract

BackgroundEctopic accumulation of fat accompanies visceral obesity with detrimental effects. Lipid oversupply to cardiomyocytes leads to cardiac steatosis, and in animal studies lipotoxicity has been associated with impaired left ventricular (LV) function. In humans, studies have yielded inconclusive results. The aim of the study was to evaluate the role of epicardial, pericardial and myocardial fat depots on LV structure and function in male subjects with metabolic syndrome (MetS).MethodsA study population of 37 men with MetS and 38 men without MetS underwent cardiovascular magnetic resonance and proton magnetic spectroscopy at 1.5 T to assess LV function, epicardial and pericardial fat area and myocardial triglyceride (TG) content.ResultsAll three fat deposits were greater in the MetS than in the control group (p <0.001). LV diastolic dysfunction was associated with MetS as measured by absolute (471 mL/s vs. 667 mL/s, p = 0.002) and normalized (3.37 s-1 vs. 3.75 s-1, p = 0.02) LV early diastolic peak filling rate and the ratio of early diastole (68% vs. 78%, p = 0.001). The amount of epicardial and pericardial fat correlated inversely with LV diastolic function. However, myocardial TG content was not independently associated with LV diastolic dysfunction.ConclusionsIn MetS, accumulation of epicardial and pericardial fat is linked to the severity of structural and functional alterations of the heart. The role of increased intramyocardial TG in MetS is more complex and merits further study.

Epicardial Adipose Tissue Volume and Left Ventricular Myocardial Function Using 3-Dimensional Speckle Tracking Echocardiography

“…23 In turn, it was known that intramyocardial triglyceride accumulation was independently associated with subclinical myocardial dysfunction in diabetic patients. 10 Although previous studies have shown that increased EAT was associated with increased LV mass and diastolic dysfunction 10,[24][25][26] , the present study demonstrated an inverse independent relationship between EAT and myocardial systolic function. Even when patients with diabetes, hypertension and coronary atherosclerosis were excluded, EAT volume was still independently correlated with longitudinal myocardial function.…”

Ectopic Fat Depots and Left Ventricular Function in Nondiabetic Men With Nonalcoholic Fatty Liver Disease

“…These data suggest that the associations of epi-and pericardial fat depots with impaired diastolic function are probably indirect and because of their close correlations with both hepatic and visceral fat depots. 13 In line, the largest study reported to date of patients with T2DM failed to demonstrate any relationship between the degree of myocardial triglyceride accumulation and diastolic function. 25 The results of our multivariable analyses suggest that visceral adiposity and hepatic triglyceride content lies at the root of the systemic toxic effects and LV Thus, both NAFLD and VAT seem to influence cardiovascular disease risk by both associating with metabolic risk and LV diastolic dysfunction.…”

“…The study recruitment has been published previously. 13 To explore the role of liver fat, the subjects were categorized into tertiles based on hepatic triglyceride content: group 1 (n=24): hepatic triglyceride low; group 2 (n=26): hepatic triglyceride moderate; and group 3 (n=25): hepatic triglyceride high. Thirty-seven participants fulfilled the criteria for the MetS.…”

“…13,17 After examination of all phases of the cine images, areas of fat layers between the myocardium and the visceral pericardium (epicardial fat) and the intrathoracic fat outside the parietal pericardium (pericardial fat) were measured in the enddiastolic image.…”

Metabolic syndrome is associated with different clinical outcome after cardiac resynchronization therapy in patients with ischemic and non-ischemic cardiomyopathy

“…The molecular mechanism postulated for the pathogenesis of cardiac complications in obesity includes lipotoxicity [28], inflammation, oxidative stress [29], apoptosis [30] and sympathetic overactivation [31]. Obesity leads to the loss of cardiomyocytes, cardiac dysfunction and ultimately HF [32].…”