OBJECTIVES: This study sought to compare outcomes after surgical valvuloplasty and balloon dilation of the aortic valve in neonates and infants. BACKGROUND: Surgical techniques of aortic valve repair have improved and there is today controversy on the best approach to treat neonatal congenital aortic valve stenosis. METHODS: Retrospective review of data and follow-up of 123 consecutive neonates and infants (35 females, 88 males) undergoing intervention for congenital aortic stenosis. RESULTS: From 1977 to 2009, 123 consecutive neonates (<30 days) and infants (31 days to 1 year) underwent relief of congenital aortic stenosis. Median age at procedure was 27 days (6 to 76 days). Twenty-year survival was 80 ± 7%. Fifty-four patients required a re-intervention and freedom from re-intervention was 55 ± 6% at 10 years and 40 ± 6% at 20 years. By multivariate analysis, having the relief of stenosis by balloon valvuloplasty and undergoing initial treatment as a neonate were predictive of re-intervention. Freedom from re-intervention at 5 years was 27% after balloon valvuloplasty versus 65% after surgery. At latest follow-up, an additional 16 patients had moderate or severe stenosis and 8 had regurgitation. Freedom from re-intervention or stenosis was 39 ± 5% at 15 years. By multivariate analysis, balloon valvuloplasty (p < 0.001) and treatment as a neonate (p = 0.003) were again predictive of stenosis or re-intervention. Thirty-five patients ultimately needed a valve replacement. Significant predictor of the requirement of valve replacement was unicuspid aortic valve (p < 0.001). Freedom from valve replacement was 55 ± 7% at 20 years. CONCLUSIONS: Surgical valvuloplasty remains the best approach to treat neonates and infants with congenital aortic stenosis. After surgery, a higher proportion of patients remain free of re-intervention than after interventional catheterization and the relief of their stenosis lasts longer.