Long-term biological variability of galectin-3 after heart transplantation.

BACKGROUND: Galectin-3 is an emerging biomarker of heart failure and of myocardial fibrosis risk. Monitoring of galectin-3 is essential during treatment with galectin-3 inhibitors. The aim of our study was to assess long-term biological variability in a specific group of unhealthy subjects. METHODS: The biological variability of galectin-3 was measured in a group of 44 patients after heart transplantation (HTx). Six samples were taken from each patient during a 12-month period. Galectin-3 was measured with an Abbott Architect automated immunoassay. RESULTS: Intraindividual (CVi) and interindividual (CVg) variabilities were calculated together with the reference change value (RCV), the log-normal RCV for increase (RCV+), and the log-normal RCV for decrease (RCV-). The CVi, CVg, RCV, RCV+, and RCV- were 28.2%, 35.6%, 78.6%, 116%, and -53.7%, respectively. The index of individuality was 0.79. CONCLUSIONS: The concentrations of galectin-3 in patients followed 12 months after HTx fluctuated around the homeostatic point, with CVi of approximately 28%. RCVs of +116% (log-normal increase) and -54% (log-normal decrease) mean that the concentration of galectin-3 would need to approximately double or decrease by half to indicate a new process.