GDF15 and fibrosis: In the present study using CMR we investigated the cross-sectional association of two pre-clinical imaging phenotypes of HF, replacement fibrosis and interstitial fibrosis, with hs-cTnT, a circulating cardiac-specific measure of myocyte injury, and GDF-15, a non-cardiac-specific biomarker considered an intermediary for inflammation, endothelial function and fibrosis (15).