The major findings were as follows: (1) β1ARAb levels were positively correlated with LA anterior-posterior diameter and three circulating fibrosis markers (PIIINP, PICP, Gal3) in PAF patients; (2) excessive expression of β1ARAbs increased LAD and interstitial fibrosis and led to increased inducibility of AF along with shortened AERP, slowed CV and increased conduction heterogeneity. Here, LGALS3 is linked to fibrosis.