A 48-person cross-sectional study based on GC-MS metabolomics was conducted to explore the relationship between fecal SCFA levels and AF characteristics. Mouse models fed diets deficient or rich in dietary fiber were established to elucidate the pathophysiological role of SCFA in AF susceptibility, atrial remodeling, and G protein-coupled receptor 43 (GPR43)/NLRP3 signaling. This evidence concerns the gene FFAR2 and atrial fibrillation.