Heart failure signs and symptoms, serum creatinine, and other hematologic and biochemical markers, were assessed daily from baseline (day 1) until discharge or day 6 and on day 7, as dictated by study protocol . Plasma NGAL levels were measured in frozen plasma samples collected on the same days and stored at −80 °C. Measurements were performed by Alere Inc. (San Diego, CA, USA) using sandwich enzyme-linked immunosorbent assays (ELISA) on a microtiter plate. The estimated glomerular filtration rate (GFR) was calculated using the simplified modification of diet in renal disease (MDRD) study equation.