Introduction and objectives: Stent implantation is an established treatment for aortic coarctation (CoA) in adults. In pediatric patients, however, ongoing somatic growth necessitates repeated stent redilations, and the optimal timing of these procedures remains undefined. This retrospective study aimed to identify an objective association between stent diameter and body growth parameters, thereby providing a basis for prognostic assessment and structured planning of redilation strategies.

Methods: In the derivation cohort, all stent implantations and redilations performed in 155 patients younger than 20 years with CoA at a tertiary center were analyzed (218 interventions; median age 10.1 years, IQR, 3.4-14.4). The findings were subsequently validated in an independent validation cohort from another tertiary center, comprising 198 patients (323 interventions; median age 7.5 years, IQR, 1.3-14.6).

Results: To assess the association between stent diameter and body growth parameters, correlation analyses were performed. Despite interindividual variability, a significant linear correlation between stent diameter and body height was identified (ꞇ: 0.737, P ≤ .001) and this finding was confirmed in the validation cohort. Based on this relationship, a formula, f(x) = 0.0831•x+1.86, where x represents body height, was derived to estimate the appropriate stent diameter. This formula yields minimum and maximum reference body heights for each stent diameter, which are reached at different ages depending on individual growth velocity. These results were subsequently translated into sex-specific reference tables.

Conclusions: The derived formula enables prediction of the required stent diameter and the anticipated number of subsequent catheter-based procedures, thereby supporting rapid estimation of intervention timing throughout somatic growth.