We will conduct a multicenter cohort study, ancillary to the Pediatric Heart Network (PHN) Residual Lesion Score (RLS) study, to investigate determinants of ND and behavioral outcomes in children with DS, focusing on the role of CHD surgery. We will only include RLS Study children with DS who had CAVSD repair, as this group comprises 91% of all children with DS in the RLS Study, with similar underlying congenital cardiac defect and surgical repair complexity, allowing our children with DS and CHD to be a homogeneous group. Moreover, one in five individuals with DS is born with an AVSD, a 2000 times higher incidence than in those with normal chromosomes. In addition to recruiting RLS Study children with DS who had CAVSD repair, we will recruit similarly-aged children with DS who do not have documented major CHD (i.e., CHD requiring previous or planned CHD surgery) to come into the same PHN site for a single study visit consisting of detailed phenotyping by completion of a Health & Developmental History Intake form, ND and behavioral assessments, and optional collection and storage of saliva specimens in the PHN Biorepository. By building our sample from RLS Study participants and recruiting a comparison group from the same PHN sites, we will leverage rich prospective data in a group of DS children with CAVSD repair from a nationally representative sample, and the expertise of the PHN and Boston Children's Hospital (BCH).
The study objective is to compare neurodevelopmental (ND) and behavioral outcomes between children with Down syndrome (DS) who had complete atrioventricular septal defect (CAVSD) repair and children from the same clinical sites with DS without major congenital heart disease (CHD) requiring previous or planned CHD surgery.