This study sought to determine the potential of recombinant B-type natriuretic peptide (nesiritide) for the treatment of pediatric decompensated heart failure. Nesiritide is a widely used and effective treatment for decompensated heart failure (HF) in adults, but its safety and efficacy in pediatric patients is unclear. Outcomes of 55 separate nesiritide infusions of varying durations in 32 patients (13 males and 19 females; mean age, 8.01 years; range, 0.01-20.4) were evaluated prospectively. All patients received nesiritide in the intensive care unit. The starting dose (0.01 microg/kg/min) was titrated to a maximum of 0.03 microg/kg/min. All patients were monitored for clinical signs and symptoms, hemodynamics, urine output, electrolytes, oxygen requirements, and oral intake. Functional status was assessed by patients and/or their parents. All patients successfully underwent initiation and titration of nesiritide infusion. No hypotension or arrhythmias were noted during 478 cumulative days of therapy. Nesiritide was given safely with vasoactive medications. Mean urine output improved from 2.35 +/- 1.71 cc/kg/hr on the day before nesiritide initiation (baseline) to 3.10 +/- 1.94 cc/kg/hr on day 4 of treatment (p < 0.01). Serum creatinine decreased from 1.04 to 0.92 mg/dl (p = 0.096), mean central venous pressure from 13 to 7 mmHg (p = 0.018), and mean weight from 30.4 to 29.7 kg (p < 0.001) with therapy. Thirst, as subjectively assessed by patients old enough to respond, decreased with infusion in 31 of 42 cases (74%). Mean New York Heart Association functional class improved significantly (p < 0.001). Nesiritide infusion, alone or in combination, is a safe treatment for decompensated HF in pediatric patients. It is associated with decreased thirst and improved urine output and functional status, and it may be efficacious in the treatment of pediatric HF.