Pulmonary artery stenosis (PAS) is a common complication of heart surgery in infancy. With recent advances in low profile-small diameter stent technology, PA stenting is now often performed in infants. While PAS stenting in older children does not impact distal PA growth and multiplication, in infants still undergoing significant PA growth, the impact of PA stent timing on long term PA development is unknown and potentially important. In a swine PAS model, the effects of early and delayed stent interventions on PA growth and cardiac function were comprehensively assessed. PA stenting had a positive impact on hemodynamics, lung perfusion, and histology, but the timing of intervention, either early or late, does not make a significant difference.