Prognostic Impact of Acute Kidney Injury in Patients With Acute Decompensated Heart Failure

Background: The relationship between acute kidney injury (AKI) in the acute phase of acute decompensated heart failure (ADHF) and patient outcome has not yet been reported. Methods and Results: Data for 625 patients with ADHF admitted to the intensive care unit were analyzed. No AKI occurred in 281 patients (no AKI) during the first 5 days. The AKI patients were assigned to 3 groups based on the timing: AKI present on admission and stable risk, injury, failure, loss, and endstage (RIFLE) class (stable early AKI; n=125), stepped-up RIFLE class (worsening early AKI; n=49), or AKI that occurred after admission (late AKI; n=170). The AKI patients were grouped into another 3 groups based on severity: class R (risk; n=214), class I (injury; n=73), or class F (failure; n=57). A multivariate logistic regression model found class I, class F, late AKI and worsening early AKI to be independently associated with in-hospital mortality. Kaplan-Meier survival curves showed that the survival rate in any-cause death during 2 years was significantly lower in class I, class F and the worsening early-AKI group, and there were significantly more HF events in class F and the worsening early-AKI group. There were significantly more class I and class F patients in the worsening early-AKI group. Conclusions: The presence of AKI on admission, worsening of AKI, and severe AKI (class I or class F) are associated with a poorer prognosis for ADHF patients. (Circ J 2013; 77: 687–696)