Work

Association of epicardial adipose tissue with circulating biomarkers in paroxysmal atrial fibrillation: insights from the RACE V study

Year: 2026

Type: article

Abstract: Aim Epicardial adipose tissue (EAT) is a metabolically active depot with established local effects, but its association to systemic processes remains unclear. The present study explored associations between EAT volume and circulating biomarkers in patients with paroxysmal atrial fibrillation (AF).Methods In RACE V, patients with paroxysmal AF were included. Baseline phenotyping included CT imaging and circulating biomarker profiling using the Olink Explore 384 Cardiometabolic panel (369 biomarkers). EAT volume was quantified on non-contrast cardiac CT and indexed for height. Linear regression and pathway enrichment analyses were performed to explore associations between EAT volume and serum biomarkers.Results A total of 564 patients with paroxysmal AF, and complete EAT and biomarker data, were included in the present analysis. Mean age was 64±10 years, 234 (41%) were female, 145 (26%) had a body mass index ≥30 kg/m 2 and 318 (56%) had an increased waist circumference. Median EAT volume was 31 (23–42) mL/m2. After adjustment for age, sex and waist circumference, 36 biomarkers remained associated with EAT volume. Gene Ontology analysis showed enrichment in immune regulation-related pathways (including regulation of T cell activation, leucocyte migration) and lipid-related pathways (including regulation of lipid storage, response to lipoprotein particles; adjusted p<0.05 for all). Reactome pathway analysis identified multiple extracellular matrix-related pathways associated with EAT volume (adjusted p<0.05 for all).Conclusions In patients with paroxysmal AF, EAT was associated with circulating biomarkers involved in pathways related to lipid metabolism, immune regulation and extracellular matrix remodelling. Further studies are needed to determine whether these associations reflect EAT-specific mechanisms or broader adiposity-related processes.

Source: Open Heart

DOI: 10.1136/openhrt-2026-004305