Neutrophil gelatinase-associated lipocalin levels in right and left heart failure: an observational study

Objective: Neutrophil gelatinase-associated lipocalin (NGAL) is a novel marker for early detection of renotubular deterioration. Despite the limited data concerning the NGAL in heart failure (HF), significance of NGAL in right-sided HF remains unknown. We assessed serum and urinary NGAL in left and right-sided HF due to non-ischemic cardiomyopathy (NICMP) and severe pulmonary arterial hypertension (PAH). Methods: In this cross-sectional observational study, we compared three groups; 35 patients with NICMP, 28 patients with PAH and 27 healthy controls. None had a serum creatinine ≥1.5 mg/dL. Plasma brain natriuretic peptide (BNP) levels, estimated glomerular filtration rate (eGFR) by Cockroft-Gault (CG) and Modification of Diet in Renal Disease Study formulas, echocardiographic measures of left and right ventricles (LV, RV) and non-invasive measurement of cardiac index (CI) by echocardiography and impedance cardiography were assessed. Differences among the groups for continuous variables were evaluated by the ANOVA and the Kruskal-Wallis test as appropriate. The Chi-square test was used for comparison of categorical variables. Results: Despite eGFR with CG formula was lower in NICMP and PAH subsets as compared to those in controls (102±27 and 99.4±29.4 vs 122.4±25.9 mL/min, p 0.05 and p 0.005 in order), serum NGAL [141 (113-151), 174 (130-192) and 132 (95-181) ng/mL] and urinary NGAL [15 (12-18), 15 (12-22) and 13 (8-18) ng/mL] levels were not different among groups (p=0.15 and p=0.35, respectively). Conclusion: Despite the mildly impaired eGFR in left-sided HF due to NICMP and right-sided HF due to PAH, neither serum, nor urinary NGAL levels are elevated in these patients.