Fibrotic Remodelling of Epicardial Adipose Tissue in Patients with Atrial Fibrillation: Comparative Analyses of Histological Findings and Computed Tomographic Imaging

ABSTRACT: Aims: We tested the hypothesis that central-marginal dispersion in adipocyte diameter in epicardial adipose tissue (EAT) would represent fibrotic remodelling of EAT, a crucial state to promote atrial myocardial fibrosis to form a substrate of atrial fibrillation (AF). We also investigated whether the central-marginal EAT density ratio by the analyses of computed tomographic (CT) imaging could predict the central-marginal adipocyte diameter ratio in EAT. Methods and results: Left atrial appendage samples were obtained from 76 consecutive AF patients during cardiovascular surgery. EAT at central area (Central EAT) and that adjacent to atrial myocardium (Marginal EAT) were evaluated. Compared to the Central EAT, the dimeter of adipocytes was smaller, fibrotic remodeling of EAT (EAT fibrosis) was more severe, and the infiltration of CD3-, CD68-, or α-SMA-positive cells were more abundant in the Marginal EAT. EAT fibrosis positively correlated with adipocyte diameter in the Central EAT, while it negatively correlated with that in the Marginal EAT, resulting in the tightly positive correlation between EAT fibrosis and the ratio of central to marginal adipocyte diameter (C/M diameter ratio) (r=0.73, p<0.01). The C/M diameter ratio was greater in patients with persistent AF (PeAF) than in those with paroxysmal AF (PAF) (p<0.01). The CT density in Central EAT and Marginal EAT was measured and their ratio (C/M density ratio) was calculated. The C/M density ratio correlated tightly with the C/M diameter ratio (r=0.69, p<0.01). Conclusion: Our results suggest that C/M adipocyte diameter ratio was associated with fibrotic remodeling of EAT and progression of AF. Our results also suggest that C/M adipocyte diameter ratio could be accurately predicted by the analyses of CT findings noninvasively.

ORGANISM(S): Homo sapiens

PROVIDER: GSE154436 | GEO | 2021/08/25

REPOSITORIES: GEO