Abstract 9913: Different Impacts of Body Fat Composition and Computed-Tomography-Determined Visceral Fat on Left Ventricular Mass, Geometry and Left Atrial Structural Alteration
Background The adverse effects of body fat distribution on left ventricular (LV) mass and geometry has recently been recognized. Excessive visceral fat deposition, specifically those surrounding the heart and central aorta, was associated with adverse cardiovascular events. We sought to examine the impact of body fat composition and visceral adipose tissue on cardiac structure and geometry.
Methods We studied 1,063 subjects (age: 49.5±10.5, 39.4% female) without angina or heart failure symptoms. Cardiac structures and LV geometry parameters including LV mass index (LVMI), relative wall thickness (RWT) and mass-to-volume ratio were all determined by echocardiography. Body fat composition (both fat and fat-free mass) was assessed by Tanita foot-to-foot bioimpedance analysis. A subgroup of 361 subjects further underwent multidetector computed tomography (MDCT) for three-dimensional, volume-based epicardial adipose tissue (EAT) and thoracic peri-aortic adipose tissue (TAT) quantification.
Results Both fat and fat-free mass were positively related to LV mass (β coef: 0.42 & 0.31, both p<0.001) after multivariate adjustment for age, gender, blood pressure and medical histories. However, only fat mass (β coef: 0.15, p<0.001) contributed independently to concentric remodeling (RWT>0.42). For each standard-deviation increase of EAT and TAT volume, there was an observed increase of LVMI (β coef: 0.14 & 0.15, both p<0.05) after multivariate adjustment. In addition, left atrial dimension was also positively related to both EAT and TAT even after adjusting for severity of mitral regurgitation (β coef: 0.16 & 0.12, both p<0.05).
Conclusions While both fat and fat-free mass exert their independent effect on ventricular mass increase, only fat mass had independent impact on ventricular geometry. Our data also suggested that epicardial adipose tissue may further impact LA dimension, possibly mediated by impeding ventricular diastolic filling.
- © 2011 by American Heart Association, Inc.