Epicardial adipose tissue volume and density are associated with heart failure with improved ejection fraction

Abstract Background Heart failure (HF) with improved ejection fraction (EF, HFimpEF) gains increasing attention as a distinct HF subtype, characterized by left ventricular reverse remodeling and myocardial recovery. Multiple cardiometabolic factors are implicated in this process. Epicardial adipose tissue (EAT), emerging as an endocrine and paracrine organ, contributes to the onset and progression of HF. However, the relation between EAT and the incidence of HFimpEF is still unclear. Methods A total of 203 hospitalized HF patients with reduced EF (HFrEF, EF≤ 40%) who underwent coronary CT angiography (CCTA) during index hospitalization were consecutively enrolled between November 2011 and December 2022. Routine follow-up and repeat echocardiograms were performed. The incidence of HFimpEF was defined as (1) an absolute EF improvement ≥10% and (2) a second EF > 40% (at least 3 months apart). EAT volume and density were semiautomatically quantified on non-enhanced series of CCTA scans. Results During a median follow-up of 8.6 (4.9~13.3) months, 104 (51.2%) patients developed HFimpEF. Compared with HFrEF patients, HFimpEF patients had lower EAT volume (126.03 ± 57.71 cm3 vs 182.74 ± 82.99 cm3 , P< 0.001) and higher EAT density (-74.92 ± 6.84 HU vs -78.76 ± 6.28 HU, P< 0.001) both in ischemic and non-ischemic HF patients. EAT density was inversely correlated with EAT volume (r= -0.33, P< 0.001). Multivariate analysis showed lower EAT volume (OR: 0.881 [95% CI 0.821~0.939]) and higher density (OR: 2.354 [95% CI 1.314~4.415]) were both independently associated with the incidence of HFimpEF, after adjusting for conventional risk factors, pharmacological therapies and baseline anthropometric parameters including body mass index. Subgroup analysis revealed that the association between EAT properties and HFimpEF was not modified by HF etiology. Conclusions This study reveals that lower EAT volume and higher EAT density are associated with development of HFimpEF. Therapies targeted at reducing EAT quantity and improving its quality might provide favorable effects on myocardial recovery in HF patients.