OBJECTIVE Recurrent coarctation is a complication which is seen at a consistent rate following all types of repair for coarctation of the aorta. Particularly disappointing late results are reported in younger infants, under 3 months of age. This retrospective analysis was undertaken to compare the outcomes on late follow-up between subclavian flap angioplasty and resection and end-to-end repair, in this age group. METHODS Over a 12-year period, between 1982 and 1994, 86 infants under 3 months of age underwent surgical repair of coarctation (39 resections and end-to-end repair, and 47 subclavian flap angioplasty procedures). Operative mortality was not significantly different (P = 0.6) between resection and end-to-end repair (5.1%) and subclavian flap angioplasty (8.5%). All operative deaths (six patients) were in infants with associated ventricular septal defects. The mean follow-up for all patients was 7.95 years +/- 4.10 (range 0-14.5 years). The 5-year survival for resection and end-to-end repair was 87 +/- 5%, compared to 75 +/- 7% for subclavian flap angioplasty (P = 0.2). RESULTS Recurrent coarctation occurred in nine patients who needed reoperation. The reoperation-free rates at both 5 and 10 years for resection and end-to-end anastomosis, and subclavian flap repair were 86 +/- 6% and 90 +/- 5%, respectively. The recurrence in the resection and end-to-end anastomosis group were due to constrictive scarring at the anastomosis, whereas periductal tissue and growth of posterior aortic ridge caused recurrence in the subclavian flap angioplasty group. There were no deaths during reoperation for recurrence. CONCLUSIONS Both procedures are extremely effective for coarctation repair in young infants and run a similar risk of recurrence, which are due to completely different mechanisms. The surgeon's expertise is the major determinant of outcome.