Objective:Children with congenital heart disease (CHD) have increased likelihood for Autism Spectrum Disorder (AuSD; Sigmon, Kelleman, Susi, Nylung & Oster, 2020). Even those not meeting full criteria remain at greater risk for problems with social processing/communication (Cassidy et al, 2018). The current study examined what symptoms indicative of potential AuSD were qualitatively reported by parents, and what symptoms were noted behaviorally by clinicians. These behaviors may be targets for both further clinical inquiry and intervention.Participants and Methods:A retrospective chart review of CHD patients seen for neuropsychological assessment between the ages of 6-18 years and between 2016-2021 was conducted. The final sample included 88 patients (Ethnicity: 14% Hispanic; Race: 76% White, 17% Black/African American, 5% Asian, 1% Native American, 1% Unknown). A coding system for AuSD symptoms was derived by the authors, who are experienced in AuSD diagnosis and assessment, based on DSM-5 criteria. A comprehensive list of behaviors consistent with each symptom category was generated, and assessment reports were subsequently reviewed noting the presence, absence or “no mention” of each symptom. A second coding system was derived to assess for AuSD symptoms documented in each report’s behavioral observations. Three pediatric neuropsychologists, one post-doctoral fellow, and one psychometrist were coders, with very good reliability (k=.854 (95% CI, .827 to .881), p < .0001).Results:Twelve patients (14%) were diagnosed with AuSD. Age of diagnosis ranged from 3-14 years (M=7.82, SD=3.92). Main concerns parents expressed included difficulty with reciprocal conversation (75%), making friends (75%), initiating and maintaining social interactions (67%), and restrictive/intense interests (58%). During testing, providers noted variable eye contact (67%), appropriate responses to questions but minimal social conversation (67%), and exaggerated prosody (42%). Of those who did not have an AuSD diagnosis, the most frequent parent concerns included difficulty making friends (38%), difficulty initiating or maintaining social interactions (33%), atypical affect (25%), and restrictive/intense interests (18%). In this sample, providers noted concerns with answering questions but not maintaining conversation (26%), flat affect (16%), loud (17%) or soft (21%) speech volume, and socially immature behaviors (10%). Within this No Diagnosis group, general social concerns were highly correlated (point biserial) with more specific autism symptoms (e.g., intense interests, difficulty with transitions, sensory sensitivities r = .986 - .784), although most often the presence or absence of these concerns were not documented.Conclusions:We examined qualitative parent-reported and provider-observed behaviors indicative of potential AuSD as detailed in a comprehensive neuropsychological evaluation report. Behaviors in children with formal AuSD diagnoses were consistent with that diagnosis, based on both parent and provider description. Of note, in children without AuSD, though, both parents and providers reported AuSD-like concerns (e.g., social communication/interaction problems, atypical interests, atypical affect, atypical speech volume) in a large minority of children. It is important that if general social concerns are present, that providers follow-up on, and document, a broader constellation of AuSD symptoms. These behaviors deserve further exploration and study within the CHD population and are important areas of inquiry in any clinical evaluation, as they should directly inform intervention.