Abstract 5153: Pericardial Fat, Intra-Thoracic Fat, and Left Ventricular Mass: The Framingham Heart Study
Pericardial fat is in direct anatomic contact with the myocardium and may lead to increased left ventricular mass (LVM). Whether the association of pericardial fat and LVM are independent of the systemic effects of obesity has not been fully explored. Participants from the Framingham Heart Study Offspring cohort (n=1006, mean age 60 years, 54% women) who underwent chest and abdominal computed tomography (CT) scanning and cine cardiac magnetic resonance imaging for left ventricular mass (LVM) quantification were included. CT scans were quantified for pericardial fat (fat within the pericardial sac), intra-thoracic fat (fat adherent to the heart but outside the pericardium), and abdominal visceral adipose tissue (VAT) using a volumetric method. Sex-specific multivariable linear regression was used to model the association of pericardial fat and of intra-thoracic fat with LVM after adjustment for age, smoking, alcohol use, menopausal status, systolic blood pressure, hypertension treatment, and height, and then additionally for VAT. Both pericardial and intra-thoracic fat were correlated with LVM in women (r=0.35, p<0.001 [pericardial fat]; r=0.37, p<0.001 [intra-thoracic fat]) and men (r=0.19, p<0.001 [pericardial fat]; r=0.17, p<0.001 [intra-thoracic fat]). In multivariable-adjusted models, both pericardial and intra-thoracic fat were associated with LVM (Table⇓). However, after adjusting for VAT, these associations were no longer significant (Table⇓). Both pericardial fat and intra-thoracic fat are associated with LVM in women and men. However, after accounting for VAT, a measure of systemic adiposity, neither pericardial fat nor intra-thoracic fat remain associated with LVM. These findings suggest that observed associations between pericardial fat and LVM are primarily due to the systemic effects of obesity.