Impact of Residual Lesion Severity on Neurodevelopmental Outcomes Following Congenital Heart Surgery in Infancy and Childhood.

Children with congenital heart disease are at increased risk of neurodevelopmental delay throughout their lifespan. This risk is exacerbated following congenital heart surgery (CHS) in infancy. However, there are few modifiable risk factors for postoperative neurodevelopmental delay. In this study, we assessed the Residual Lesion Score (RLS), a quality assessment metric that evaluates residual lesion severity following CHS, as a predictor of neurodevelopmental delay. This was a single-center, retrospective review of patients who underwent CHS from 01/2011 to 03/2021 and post-discharge neurodevelopmental evaluation from 12 to 42 months of age using the Bayley Scales of Infant Development, 3rd Edition (BSID-III). RLS was assigned per published criteria: RLS 1, no residua; RLS 2, minor residua; and RLS 3, major residua or pre-discharge reintervention. Associations between RLS and BSID-III scores, as well as trends in neurodevelopmental outcomes over time, were evaluated. Of 517 patients with median age at neurodevelopmental testing of 20.0 (IQR 18.0-22.7) months, 304 (58.8%), 146 (28.2%), and 67 (13.0%) were RLS 1, 2, and 3, respectively. RLS 3 patients had significantly lower scaled scores in the cognitive, receptive, and expressive communication, and fine and gross motor domains, compared with RLS 1 patients. Multivariable models accounted for 21.5%-31.5% of the variation in the scaled scores, with RLS explaining 1.4-7.3% of the variation. In a subgroup analysis, RLS 3 patients demonstrated relatively fewer gains in cognitive, expressive communication, and gross motor scores over time (all p < 0.05). In conclusion, RLS 3 patients are at increased risk for neurodevelopmental delay, warranting closer follow-up and greater developmental support for cognitive, language, and motor skills soon after surgery.