Between September 1980 and August 1988, 47 patients younger than 12 months (27 neonates and 20 infants) underwent repair of aortic coarctation. Three surgical techniques were used: patch aortoplasty (group A: 5 neonates and 3 infants, mean age 4.5 months), subclavian flap (group B: 11 neonates and 8 infants, mean age 3.1 months), and the combined resection-flap procedure (group C: 11 neonates and 9 infants, mean age 2.7 months). There were 8 early deaths (3 in group A, 3 in group B, and 2 in group C) and 2 late deaths (both in group B), all of which occurred in patients with complex coexisting anomalies. Follow-up included 37 patients (5 in group A, 14 in group B, and 18 in group C) and ranged from 28 to 108 months (mean 68.0, 60.8, and 51.7 months, respectively). Residual arm-leg pressure gradients greater than 10 mm Hg were detected in 4 of 5 patients in group A, 11 of 14 patients in group B, and 1 of 18 patients in group C (p less than 0.005). There were no reoperations in any infant operated on after 1 month of age in any group (0% risk). However, 4 patients who underwent repair during their neonatal period, with recurrent gradients greater than 20 mm Hg, have required reoperation: in group A, 1 of 5 patients (20% risk) (1 of 2 neonates or 50% risk); in group B, 3 of 14 patients (21% risk) (3 of 9 neonates or 33% risk); and none in group C (0% risk in infants and neonates) (p less than 0.001). In summary, residual gradients and risk of recoarctation are significantly higher when a patch or a subclavian flap had been used for repair. The combined resection-flap procedure (an end-to-end anastomosis enlarged with a subclavian flap) is more effective in avoiding gradients and preventing recoarctation, especially in neonates.