Introduction: Acute decompensated heart failure (ADHF) in children commonly results in hospitalization and intravenous vasoactive (IVV) drug support. We sought to identify factors associated with the use of IVV support, and successful weaning of this support.

Methods: This single center retrospective cohort study analyzed hospitalized children aged 1 month to 18 years with biventricular physiology, a systemic left ventricle, and symptomatic ADHF from 2005-2021. Clinical, laboratory and echocardiographic measures on admission, and all BNP levels during 0-30 days after admission were assessed. Major adverse cardiac event (MACE) outcomes were defined as first occurrence of mechanical circulatory support (MCS), heart transplant (HT), or death. Serial changes in BNP levels were evaluated using linear mixed effect modelling. Logistic regression was used to investigate risk factors for MACE.

Results: In 158 hospitalizations of 131 patients with median age of 4.5 years (IQR 0.8-12.4), IVV support was used in 70% (N=110). MACE occurred in 63(40%), with 41 (26%) requiring MCS, HT in 12 (7.6%), and death in 10 (6.3%) as the first event. IVV support was associated with a lower admission LV EF(25.7% versus 31.1%, p=0.002), concurrent RV dysfunction (42.7% vs. 12.5%, p&lt0.001) and, no prior oral HF therapy (43.6% vs. 62.5%, p=0.03). In addition, the group of patients that used IVV support had higher initial BNP (1080 vs. 638mg/dL, p=0.02), BUN (16 vs. 11 mg/dL, p=0.02) and creatinine levels (0.51 vs.0.39 mg/dL, p= 0.002). In 1267 serial BNP measurements (in 110 admissions), the decline in log BNP level was slower in patients on IVV support (-0.08 vs.-0.24 2log pg/dL/day, p=0.04). Of those patients on IVV support, BNP declined more rapidly in children who were later weaned from IVV, halving in 6-7 days(-0.16 vs. -0.03 2log pg/dL/day, p&lt0.001). In a multivariate logistic regression, of the admission risk factors, only the presence of RV dysfunction was associated with MACE (OR: 3.6 (CI: 1.5-8.6) p=0.004).

Conclusions: Pediatric patients hospitalized with ADHF frequently receive IVV support and are at high risk for MACE. The rate of decline of serial BNP levels is associated with successful weaning from IVV. RV dysfunction was associated with MACE in this cohort.