Association Between Mineralocorticoid Receptor Antagonist Use With Worsening Renal Function and Prognosis in Patients With Acute Heart Failure.

Background: Prognostic implications of mineralocorticoid receptor antagonist (MRA) initiation in the context of worsening renal function (WRF) in patients with acute heart failure (AHF) remain unknown.

Methods: This was a post hoc analysis using data from Japanese AHF registries (NARA-HF [Nara Registry and Analyses for Heart Failure], WET-HF [West Tokyo Heart Failure], REALITY-AHF [Registry Focused on Very Early Presentation and Treatment in Emergency Department of Acute Heart Failure]). MRA-naïve patients at baseline were included, comprising 1632 patients with HF with reduced ejection fraction (HFrEF) and 2407 with heart failure with mildly reduced or preserved ejection fraction (HFmr/pEF). They were divided into 3 groups: MRA initiated without WRF (HFrEF, n=590; HFmr/pEF, n=572), MRA initiated with WRF (HFrEF, n=74; HFmr/pEF, n=100), and no MRA initiation (HFrEF, n=968; HFmr/pEF, n=1735). WRF was defined as a 0.3 mg/dL increase from admission to discharge. The composite of death or HF hospitalization after discharge was assessed.

Results: During the 1-year follow-up, 369 and 593 events occurred in patients with HFrEF and HFmr/pEF, respectively. Overall, MRA initiation during hospitalization of AHF was independently associated with better prognosis (hazard ratio [HR], 0.81), mainly driven by HF hospitalization. Among patients with HFrEF, the groups with MRA with and without WRF showed a lower incidence of the outcome than the no-MRA group, even after adjusting for risk factors (HR, 0.75 and 0.49, respectively). Among patients with HFmr/pEF, MRA initiation without WRF was independently associated with better prognosis (HR, 0.78), but MRA initiation with WRF was not.

Conclusions: Initiating an MRA during AHF hospitalization was associated with better postdischarge outcomes in HFrEF, irrespective of creatinine elevation, whereas no such consistent association was observed in HFmr/pEF.