Is the Definition of Worsening Renal Function Enough for the Evaluation of Acute Renal Failure in Acute Heart Failure?

Background: It was not elucidated if the definition of worsening renal function (WRF) was adequate for the evaluation of renal dysfunction in patients with acute heart failure (AHF). Methods and Results: One-thousand eighty-three patients with AHF patients were analyzed. WRF which was a change in serum creatinine ≥0.3 mg/ml during the first five days occurred in 360 patients, meanwhile; no WRF which was a change <0.3 mg/dl in 723 patients. Acute kidney injury (AKI) upon admission was defined based on the ratio of the serum creatinine value recorded on admission to the baseline creatinine value, and classified as following: no-AKI or Class R (risk; n = 193), Class I (injury; n = 41) or Class F (failure; n = 98). The patients were also assigned to four groups: no-WRF/no-AKI (n = 512), no-WRF/AKI (n = 211), WRF/no-AKI (n = 239) and WRF/AKI (n = 121). A multivariate logistic regression model found that no-WRF/AKI and WRF/AKI were independently associated with 365-day mortality (HR: 1.916; 95%CI: 1.234–2.974, and HR: 3.622; 95%CI: 2.332–5.624). Kaplan-Meier survival curves showed that the any-cause death during one-year was significantly poorer in no-WRF/AKI and WRF/AKI than in WRF/no-AKI and no-WRF/no-AKI, and in Class I and Class F than in Class R and no-AKI. Conclusions: The presence of AKI on admission, especially Class I and Class F are associated with a poorer prognosis, even they were not developed WRF within 5-days.