HYAL4 and atrial fibrillation: In addition to ECM gene upregulation, the expression of ECM degrading constituents was increased in par‐AF and pers‐AF, such as hyaluronidases (HYAL1, HYAL2, HYAL4), and a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) families (Figure S5).