Neo-aortic Root Dilatation Following Ross Procedure in School-Aged Children.

Neo-aortic root dilatation after the Ross procedure is well described in adults, and reinforced autograft techniques are used in this group, but data for children are limited. We aimed to identify the age at which the risk of dilatation begins to increase and to investigate whether an age or body surface area threshold exists. Patients treated between January 2006 and January 2025 at a single centre were reviewed retrospectively. Freedom from dilatation was estimated by the Kaplan-Meier method; associations with age and body surface area at operation were assessed by Cox regression. Of 96 children who underwent the Ross or Ross-Konno procedure, 68 had echocardiographic follow-up and 59 received free-standing autograft implantation (20 school-aged, 39 younger; median follow-up 6.9 years). Dilatation (Z-score ≥4) was documented in 6 of 20 school-aged (30.0%) and 4 of 39 younger children (10.3%), with incidence rates of 7.1 and 1.2 per 100 patient-years. School-aged patients had lower freedom from dilatation (log-rank p = 0.005), and each additional year of age increased the hazard of dilatation (hazard ratio 1.26, 95%CI 1.08-1.49; p = 0.003). Two patients required mechanical aortic valve replacement; none required reoperation for isolated dilatation, and there were no deaths among the 59 patients during follow-up. In our cohort, school-aged children appeared to carry a higher risk of neo-aortic root dilatation than children operated at younger ages. These findings suggest that closer echocardiographic surveillance may be appropriate in this group, and that extending reinforced autograft techniques below the adolescent threshold warrants prospective evaluation.