T2DM patients treated with SLGT2i, who developed HFpEF after 3 years of follow-up, had higher PICP, PIIINP, Gal-3, and NT-proBNP serum concentrations at baseline, and Gal-3 level was an independent predictor of HFpEF. The gene discussed is NPPB; the disease is type 2 diabetes mellitus.