Acute heart failure (AHF) is frequently complicated by fluid overload, where timely decongestion must be balanced against the risk of renal dysfunction and electrolyte imbalance. The Fluid Management of Acute Decompensated Heart Failure Subjects Treated With Reprieve Decongestion Management System (FASTR) trial published in the JACC Heart Failure assessed whether the Reprieve Decongestion Management System (DMS) could improve decongestion efficiency compared with optimal diuretic therapy (ODT).

This randomized pilot study enrolled 100 hospitalized AHF patients, of whom 96 received assigned treatment (Reprieve: n=52; ODT: n=44). Participants had a median estimated glomerular filtration rate (eGFR) of 49 mL/min/1.73 m² and a median excess fluid volume of 20 lbs. The primary efficacy endpoint was 24-hour natriuresis, while safety was assessed using a composite of dialysis requirement, doubling of serum creatinine, severe electrolyte disturbances, hypotension, or hypertensive emergency.

The Reprieve system achieved significantly higher 24-hour natriuresis compared with ODT (1,082±487 mmol vs 423±290 mmol; p<0.001). Rates of the composite safety endpoint were similar between groups (31% vs 39%; p=0.42). Reprieve also reduced the duration of intravenous diuretic therapy (median 46 vs 88 hours; p=0.014) and demonstrated faster weight loss (p=0.002), greater net fluid loss (p=0.03), and increased cumulative natriuresis (p<0.001). Changes in serum creatinine were not significantly different between groups (p=0.07).

In this randomized pilot trial, automated diuretic titration facilitated more rapid decongestion without increasing adverse events. Larger trials are required to confirm clinical benefits and long-term outcomes.