BACKGROUND Operative resection is the treatment of choice for native aortic coarctation in most institutions. The ideal timing for elective repair is still a matter of debate. This study evaluated one institution's results with resection and end-to-end anastomosis in the first year of life. METHODS Between January 1987 and December 1993, 46 neonates and infants with functionally isolated aortic coarctation underwent operative resection and end-to-end anastomosis. For the patients included in the study, all hospital records, catheterization data, and operative protocols were evaluated for retrospective analysis. To obtain valid follow-up information, all patients were systematically seen on an outpatient basis during 1994. RESULTS After a mean follow-up of 49 +/- 24 months (range, 13 to 95 months), recoarctation (arm-leg blood pressure gradient > 20 mm Hg) occurred in 5 of 26 patients with neonatal operations (19%) and in 1 of 20 patients with operations in infancy (5%, p = not significant). Four of these 6 children with recoarctation needed reintervention. The other 2 patients had only mild recoarctation (gradients of 22 and 30 mm Hg, respectively) and were not treated. In all 6 patients, recoarctation was diagnosed within the first 6 months postoperatively. During the whole follow-up period, right arm systolic blood pressures slightly above the 90th percentile of normal developed in 11 of the patients (24%) (7 in the group with neonatal operation and 4 after operation in infancy; p = not significant). CONCLUSIONS Resection with end-to-end anastomosis was shown to be an adequate therapeutic strategy for isolated aortic coarctation in neonates and infants. The results indicate that already beyond the neonatal age, there is a relatively low incidence of recoarctation.