Epicardial Fat as a Contributing Factor to Diastolic Dysfunction

Abstract

Background: As one of forces extrinsic to the myocardium, we hypothesized that epicardial fat may contribute to diastolic dysfunction. The objective of this study was to evaluate epicardial fat as a contributing factor to diastolic function. Methods: Two hundred and twenty-one patients without significant arrhythmia, left ventricular hypertrophy, significant valvular disease, decreased left ventricular systolic function, or coronary artery disease were studied. Epicardial fat thickness on the free wall of the right ventricle was measured at end-diastole from the parasternal long-axis views of 3 cardiac cycles. Diastolic function was evaluated using the left atrium volume index, mitral inflow parameters (E, A, E/A, DT [deceleration time]) and mitral annular tissue-Doppler imaging parameters (E’, A’, E/E’). Results: Two hundred and twenty-one patients were divided into 2 groups according to diastolic pattern (normal versus abnormal mitral inflow pattern). There were significant differences in epicardial fat thickness (0.31±0.11 mm vs. 0.48±0.2 mm; P<0.001). Epicardial fat thickness was significantly correlated with a high E/E’ (r=0.395, P<0.001) and high left atrium volume index (r=0.230, P=0.005). Multiple linear regression showed that epicardial fat thickness (β=0.250, t=2.756, P=0.005), left atrium volume index (β=0.273, t=3.270, P=0.007), and A (β=0.454, t=4.722, P=0.0001) were significant predicting factors for E/E’, whereas clinical parameters such as age, sex, hypertension, diabetes, metabolic syndrome, and high density lipoprotein cholesterol had no statistical significance. Conclusion: Our study showed that epicardial fat thickness is significantly related to diastolic dysfunction.