ADAMTS4 and atrial fibrillation: FMOD is extensively fragmented in IVDD 54, 45, and 32 kDa fragments are prominent and can be generated in vitro using MMP‐13 and ADAMTS4 and ADAMTS‐5 to a lesser extent. These fragments show potential as catabolic biomarkers of IVDD and have been spatiotemporally correlated with annular remodeling in an ovine model of IVDD but are not present in the morphologically normal contralateral AF.