Novel biomarkers assessing renal function in heart failure: relation to inflammatory status and cardiac remodelling.

BACKGROUND Patients with heart failure (HF) have a significant decline of renal function. We investigate the association between novel biomarkers of renal dysfunction and indices of inflammatory status and cardiac remodeling in patients with HF. METHODS We enrolled 79 consecutive patients with HF and 79 healthy subjects, adjusted for age and sex. Serum levels of neutrophil gelatinase-associated lipocalin (NGAL), cystatin-C, b-type natriuretic peptide (BNP), tumor necrosis factor alpha (TNFα) and matrix metalloproteinase-9 (MMP-9) were measured by ELISA. Creatinine clearance was estimated using Cockcroft-Gault formula (eCcl). Left ventricular ejection fraction was determined by echocardiography. RESULTS Patients with HF, compared to healthy subjects, had significantly higher NGAL (p=0.007) and cystatin-C levels (p=0.005). In HF patients, NGAL levels were positively correlated with Creatinine levels (r=0.40, p<0.001), TNFa levels (r=0.43, p<0.001), BNP levels (r=0.36, p=0.003), MMP-9 levels (r=0.37, p=0.02) and inversely correlated with left ventricle ejection fraction (r=-0.23, p=0.045). Interestingly, the association between NGAL and MMP-9 levels was independent from confounders such as age, gender, left ventricle ejection fraction, body mass index, TNFα levels, and BNP levels. Moreover, in HF patients, cystatin-C levels were inversely correlated with eCcl (r=-0.21, p=0.04). Cystatin-C levels were not correlated with TNFa, BNP, MMP-9 levels and with left ventricle ejection fraction (p=NS for all). CONCLUSIONS NGAL is associated with left ventricle ejection fraction, and biomarkers of inflammation and cardiac remodeling in patients with HF. These findings highlight a possible common pathogenetic mechanism of renal dysfunction, inflammatory process and cardiac dysfunction in HF.