Managing persistent congestion in patients with chronic heart failure (HF) can be challenging, particularly when renal dysfunction and diuretic resistance limit the effectiveness of conventional therapy. Identifying factors that predict response to different diuretic strategies may help optimize treatment in this high-risk population.

Investigators conducted a prespecified post hoc analysis of the DEA-HF randomized crossover trial, which evaluated three diuretic regimens in ambulatory patients with congestion-refractory HF. The study was published in the European Heart Journal Cardiovascular Pharmacotherapy. Forty-two patients received, in random sequence, intravenous furosemide alone, oral metolazone plus intravenous furosemide, and intravenous acetazolamide plus intravenous furosemide.

Findings

• Patients with eGFR greater than 30 mL/min/1.73 m² achieved significantly higher natriuresis (4,735 mg vs 3,211 mg; P=0.0004) and diuresis (1.93 L vs 1.49 L; P=0.0078) than those with lower eGFR.
• Among patients with eGFR greater than 30 mL/min/1.73 m², adding metolazone to furosemide produced greater natriuresis than acetazolamide plus furosemide (5,525 mg vs 4,379 mg; P=0.04) and furosemide alone (5,525 mg vs 4,303 mg; P=0.014).
• In patients with eGFR of 30 mL/min/1.73 m² or lower, neither metolazone nor acetazolamide provided additional natriuretic benefit compared with furosemide alone.
• Higher serum bicarbonate levels were independently associated with greater natriuresis (4,858 mg vs 3,576 mg; P=0.0008) and diuresis (1.99 L vs 1.56 L; P=0.0014).

The findings suggest that renal function and serum bicarbonate levels may help identify patients most likely to benefit from intensified diuretic strategies. In congestion-refractory HF, metolazone appeared to enhance natriuresis in patients with relatively preserved kidney function, whereas additional diuretic agents offered limited benefit in those with more advanced renal impairment.