<p>Percutaneous Balloon Pulmonary Valvuloplasty (BPV) is the gold standard treatment for isolated pulmonary valve stenosis in the pediatric population. However, its long-term outcomes and associated risk factors remain incompletely characterized. This systematic review aimed to assess BPV long-term outcomes and predictors for restenosis/reintervention and pulmonary insufficiency (PI) following BPV in this population. PubMed, Scopus, Web of Science and Cochrane databases were searched to identify studies including pediatric populations with a minimum follow up of five years after BPV (ranging up to 20 years). Fifteen studies were included, comprising 1505 patients. BPV was associated with sustained relief of pulmonary valve stenosis and low procedure-related and late mortality (ranges 0-4.2% and 0–6%, respectively). Restenosis occurred in a minority of patients, (range 0–38%), and reintervention was uncommon (median rates: repeat BPV 5.0%, surgery 4.5%). Both were consistently associated with unfavorable hemodynamic characteristics including a higher initial transvalvular pulmonary gradient or a higher right ventricular overload and residual obstruction after the procedure, as well as unfavorable anatomical characteristics including a smaller pulmonary valve annulus size. PI was the most frequently late outcome identified (range 5.6%-60%), and was predominantly associated with younger age at intervention, lower body weight and greater severity of stenosis at baseline. Pulmonary valve replacement remained uncommon during follow-up (range 0-12.3%, median 1.4%). These results highlight the differential impact of anatomical, hemodynamic and procedural factors on long-term outcomes after BPV in pediatric patients. Due to substantial heterogeneity in outcome definitions and gradient assessment methods, results were synthesized narratively.</p>