Cardiac Steatosis Associates With Visceral Obesity in Nondiabetic Obese Men

University of Helsinki, Helsinki, Uusimaa, Finland
The Journal of Clinical Endocrinology and Metabolism (Impact Factor: 6.21). 03/2013; 98(3):1189-97. DOI: 10.1210/jc.2012-3190
Source: PubMed


Liver fat and visceral adiposity are involved in the development of the metabolic syndrome (MetS). Ectopic fat accumulation within and around the heart has been related to increased risk of heart disease. The aim of this study was to explore components of cardiac steatosis and their relationship to intra-abdominal ectopic fat deposits and cardiometabolic risk factors in nondiabetic obese men.

Myocardial and hepatic triglyceride (TG) contents were measured with 1.5 T magnetic resonance spectroscopy, and visceral adipose (VAT), abdominal subcutaneous tissue (SAT), epicardial and pericardial fat by magnetic resonance imaging in 37 men with the MetS and in 40 men without the MetS.

Myocardial and hepatic TG contents, VAT, SAT, epicardial fat volumes, and pericardial fat volumes were higher in men with the MetS compared with subjects without the MetS (P < .001). All components of cardiac steatosis correlated with SAT, VAT, and hepatic TG content and the correlations seemed to be strongest with VAT. Myocardial TG content, epicardial fat, pericardial fat, VAT, and hepatic TG content correlated with waist circumference, body mass index, high-density lipoprotein cholesterol TGs, very low-density lipoprotein-1 TGs, and the insulin-resistance homeostasis model assessment index. VAT was a predictor of TGs, high-density lipoprotein cholesterol, and measures of glucose metabolism, whereas age and SAT were determinants of blood pressure parameters.

We suggest that visceral obesity is the best predictor of epicardial and pericardial fat in abdominally obese subjects. Myocardial TG content may present a separate entity that is influenced by factors beyond visceral adiposity.

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    • "Perfusion of hearts with TG-enriched lipopoproteins reproduces the metabolic abnormalities of myocardial steatosis (Pillutla et al., 2005). Myocardial steatosis (Granér et al., 2013) and ECM remodelling (Hayden et al., 2006) are crucial events in the cardiometabolic syndrome. Myocardial steatosis, in particular, is considered an independent predictor of diastolic dysfunction in diabetic patients (Rijzewijk et al., 2008). "
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    ABSTRACT: Background and Aim Cardiac steatosis has been related to increased risk of heart disease. We investigated the association between cardiac steatosis, electrocardiographic (ECG) abnormalities, and individual components of the metabolic syndrome (MetS). Material and methods A 12-lead ECG and laboratory data were examined in 31 men with the MetS and in 38 men without the MetS. Myocardial triglyceride (MTG) content was measured with 1.5 T magnetic resonance (MR) spectroscopy and epicardial and pericardial fat by MR imaging. Results MTG content, epicardial and pericardial fat depots were higher in men with the MetS compared with subjects without the MetS (p<0.001). The heart rate was increased (p<0.001), the PR interval was longer (p<0.044), the frontal plane QRS axis shifted to the left (p<0.001), and the QRS voltage (p<0.001) was lower in subjects with the MetS. The frontal plane QRS axis and the QRS voltage were inversely correlated with MTG content, waist circumference (WC), body mass index (BMI), TGs, and fasting blood glucose. High-density lipoprotein cholesterol correlated positively and measures of insulin resistance negatively with the QRS voltage. MTG content and hypertriglyceridemia were determinants of the frontal plane QRS and WC and hyperglycemia were predictors of the QRS voltage. Conclusion The MetS and cardiac steatosis appear to associate with multiple changes on 12-lead ECG. The frontal plane QRS axis is shifted to the left and the QRS voltage is lower in subjects with the MetS. Standard ECG criteria may underestimate the presence of left ventricular hypertrophy in obese subjects with cardiometabolic risk factors.
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