Galectin-3

Galectin-3 is a 30-kDa beta-galactoside-binding lectin secreted by activated macrophages that drives myocardial fibroblast proliferation, collagen deposition and adverse cardiac remodelling. It is measured in plasma or serum by an FDA-cleared ELISA or Vidas/Architect chemiluminescent immunoassay; multicentre validation (Christenson 2010) reported 90th, 95th and 97.5th percentile cutoffs of approximately 17.6, 20.3 and 22.1 ng/mL in apparently healthy adults, and de Boer 2011 reported that levels above 17.8 ng/mL are associated with higher heart-failure mortality. The 2017 ACC/AHA/HFSA focused update gave galectin-3 a Class IIb recommendation for additive risk stratification, but the 2022 AHA/ACC/HFSA heart-failure guideline (Heidenreich et al.) and the 2021 ESC HF guideline downgraded routine galectin-3 measurement relative to natriuretic peptides; current use is limited to research and select prognostic settings. Major confounders include age (rises modestly), chronic kidney disease (eGFR is the strongest non-cardiac determinant), pulmonary fibrosis, hepatic fibrosis, and active malignancy; assay platform differences mean serial measurements should use the same method.