Gene expression of anabolic genes collagen type I (Col1) and type II (Col2) and ACAN, catabolic genes matrix metalloproteinase 1, 3, and 13 (MMP1, MMP3, MMP13), as well as ADAM metallopeptidase with thrombospondin type 1 motif4 and motif5 (ADAMTS4, ADAMTS5) and inflammatory genes interleukin 6 (IL6) and 8 (IL8) was determined from AF at the injury or repair site and intact (control) side, as shown in Figure 9. This evidence concerns the gene MMP13 and atrial fibrillation.