In patients with CKD, particularly those who have HFpEF, Eiros et al. described a link between LVDD and the biomarker combination of high carboxy-terminal propeptide of procollagen type-I (PICP) and low carboxy-terminal telopeptide of collagen type-I to matrix metalloproteinase-1 (CITP:MMP-1) ratio. The gene discussed is MMP1; the disease is chronic kidney disease.