Circulating intestinal fatty acid-binding protein (I-FABP) levels in acute decompensated heart failure

Background Venous congestion has become increasingly recognized as a potential contributor to end-organ dysfunction in heart failure. Elevated I-FABP, which is excreted specifically from damaged intestinal epithelial cells, has been found in patients with abdominal hypertension and intestinal ischemia. We hypothesize that elevated intestinal fatty acid-binding protein (I-FABP) levels would identify patients with more advanced heart failure who have venous and intestinal congestion. Methods Baseline serum I-FABP levels were measured in 69 acute decompensated heart failure (ADHF) patients admitted to the intensive care unit for invasive hemodynamic monitoring and tailored medical therapy. Comprehensive echocardiography examinations were performed in all study patients, and clinical outcomes (death, cardiac transplant or left ventricular assist device placement) were assessed. Results The median circulating I-FABP level was 853 pg/ml (interquartile range: 533 to 1448 pg/ml). Age, gender, race, and baseline comorbidities were comparable between patients with low and high I-FABP levels. Although there were no significant correlations between I-FABP levels and invasively-measured hemodynamic parameters nor echocardiographic parameters, patients with higher I-FABP levels (≥ 853 g/ml) had significantly worse clinical outcomes compared to those with lower I-FABP levels (< 853 pg/ml, P = 0.025). Conclusion Circulating I-FABP levels had no association with invasively-measured hemodynamic parameters, but were associated with adverse clinical outcomes in patients with ADHF with systolic dysfunction.