Abstract 9885: Pericardial Fat is Associated With Atrial Electrical Function: The Framingham Heart Study

Abstract

Background: Obesity is a significant risk factor for atrial fibrillation (AF). Pericardial fat (Pfat) - unique for having direct myocardial contact - has been associated with AF. We hypothesized that Pfat is significantly related to atrial electrical function (AEF) as quantified by P wave indices (PWI), intermediate endophenotypes of AF risk. Methods: We performed a cross-sectional analysis of 1,946 Framingham Heart Study participants (45% female) to assess the relations between Pfat and AEF measured by PWI: PR interval, P wave duration (Pdur), P wave amplitude (Pamp), P wave area (Parea), and P wave terminal force (Pterm). We performed sex stratified, multivariable linear regression analyses adjusting for age, heart rate, blood pressure, AV nodal medications, hormone replacement therapy, hypertension, diabetes, and menopausal status in women, followed by adjustment for ectopic fat depots in secondary analyses. Results: We determined that a 1-SD increase in Pfat was significantly associated with PWI magnitude: PR interval (β=1.67, p=0.049), Pdur (β=2.32, p<0.001), and Pterm (β=297, p<0.001) among women; and Pdur (β=1.19, p=0.002), Pamp (β=-2.51, p<0.001), and Pterm (β=160, p=0.002) among men. We constructed sex-stratified restricted cubic splines to assess the relation between Pfat and Pdur ( 1a) and Pterm ( 1b): Among both sexes, Pfat was significantly associated with Pdur in models additionally adjusting for visceral fat or intrathoracic fat; a similar trend existed with Pterm. Among women, Pfat was significantly associated with Parea after adjustment for visceral and intrathoracic fat. Conclusions: Pfat is associated with altered AEF quantified by PWI, and the associations are independent of thoracic and visceral fat. These findings suggest altered AEF may be an intermediate step in the relation of Pfat and AF.