Evolutional change in epicardial fat and its correlation with myocardial diffuse fibrosis in heart failure patients

Objectives The aim of this study was to characterize the characteristics of epicardial fat (EAT) in different stage heart failure (HF) patients and its relationship between cardiac fibrosis. Background EAT is visceral adipose tissue that possesses inflammatory properties. Inflammation and obesity are associated with cardiac fibrosis, but the relationship between cardiac fibrosis and EAT is unknown. Methods EAT volume was measured using cardiac magnetic resonance imaging (CMR) in 180 subjects: 58 patients with systolic HF, 63 patients with HF and preserved ejection fraction, and 59 patients without HF. CMR derived myocardial extracellular volume (ECV) was used for fibrosis quantification. Results Patients with systolic HF had significantly more EAT compared with patients with HF and preserved ejection fraction or the control group (patients without HF) (indexed EAT volume [mL/m²], 27.0 [22.7–31.6] vs 25.6 [21.4–31.2] and 24.2 [21.0–27.6], P <.05). The adjusted EAT amount was associated with ECV completely independent of age, hypertension, diabetes, etiology of HF, left ventricular ejection fraction, CMR–late gadolinium enhancement (LGE), left ventricular mass index, and left ventricular end-diastolic volume index (correlation coefficient: 0.49; 95% confidence interval: 0.12–0.86, P <.01). Increased CMR ECV was more associated with EAT in those with advanced age, male sex, LGE on magnetic resonance imaging–LGE images, and less left ventricular end-diastolic volume index. Conclusions EAT volume is highly associated with CMR ECV independent of traditional risk factors and left ventricular mass or volume. Whether EAT plays a role in the long-term prognosis of HF requires future investigation.