Between January 1962 and December 1991, 179 children less than 1 year of age underwent repair of coarctation of the aorta. Group I (1962 to 1971) consisted of 19 patients, group II (1972 to 1981) of 57 patients, group III (1982 to 1991) of 103 patients. Neonates (< 30 days old) made up 60% of group I, 57% of group II, and 70% of group III. The proportion of infants with associated complex cardiac abnormalities was 7% in group I, 25% in group II, and 39% in group III. Techniques of repair included resection with end-to-end anastomosis (n = 65), subclavian flap repair (n = 85), patch aortoplasty (n = 18), and other procedures (n = 11). The early mortality (< 30 days) was lowest in group III (group I, 21%; group II, 21%; and group III, 7%; p < 0.05), but the late mortality was similar in all groups (group I, 11%; group II, 13%; and group III, 15%). The overall actuarial survival was 57.7% +/- 0.15% at 27.1 years in group I, 65.7% +/- 0.07% at 19.7 years in group II, and 77.5% +/- 0.04% at 9.3 years in group III (p = not significant). Twenty-five restenoses requiring intervention occurred in 23 patients, for an overall restenosis rate of 16.4%. The incidence of restenosis was 23% for the patients who underwent end-to-end anastomosis, 11% for those who underwent subclavian flap repair (p < 0.1), and 27% for those who underwent patch aortoplasty (p < 0.01). Balloon angioplasty was successful in relieving 11 of the 12 restenoses in groups II and III.(ABSTRACT TRUNCATED AT 250 WORDS)