Background: Galectin-3 affects cardiac tissue inflammation as an inflammatory mediator. The development of cardiorenal syndrome in heart failure patients is associated with a poor prognosis. This study aims to investigate whether serum galectin-3 levels can be used as a biomarker to predict cardiorenal syndrome in heart failure patients with reduced left ventricular ejection fraction.

Methods: A total of 166 symptomatic heart failure patients [New York Heart Association (NYHA) functional class II-III] with reduced left ventricular ejection fraction (≤ 40%) were recruited prospectively. Cardiorenal syndrome type 1 was defined as an acute worsening of cardiac function leading to renal dysfunction. The patients were divided into two groups with and without cardiorenal syndrome. The galectin-3 levels of all patients were determined. The primary outcome of this study was the occurrence of cardiorenal syndrome.

Results: Cardiorenal syndrome developed in 41 patients. Galectin-3 levels were found to be higher in the patients with cardiorenal syndrome (+) compared to those without cardiorenal syndrome (-) (20.7 ± 2.9 ng/mL vs. 17.8 ± 3.1 ng/mL, p < 0.001). After performing a multivariable analysis, galectin-3 levels [odds ratio (OR): 3.21, p = 0.001], NYHA functional class (OR: 1.98, p = 0.009), creatinine (OR: 3.18, p = 0.006), furosemide dose (OR: 1.21, p = 0.033), and angiotensin-converting enzyme inhibitor/angiotensin-receptor blockers usage (OR: 0.54, p = 0.029) were identified as independent predictors for the development of cardiorenal syndrome. Moreover, galectin-3 level demonstrated predictive capability for cardiorenal syndrome development (AUC = 0.761, p < 0.001).

Conclusions: Serum galectin-3 level showed an association with cardiorenal syndrome development in patients with heart failure, indicating potential usefulness as a prognostic biomarker.