Abstract Body (Do not enter title and authors here): Introduction: Previous research has described barriers and facilitators for adherence to care guidelines among adults with congenital heart disease (CHD). However, uncertainty remains on how to best support patients in clinical practice within time and resource constraints.

Aim: To examine how patients incorporate CHD into their identity and how that influences the management of their condition.

Methods: We conducted 48 semi-structured qualitative interviews with adult CHD patients and providers (cardiologists, nurses, patient coordinators, and social workers). Purposive sampling was used to gain patient diversity in CHD lesions, race/ethnicity, SES, geography, and prior gaps in care. Interviews were conducted by a single interviewer using a semi-structured guide based on the “Capability, Opportunity, Motivation-Behavioral (COM-B)” Framework to explore perceived determinants of behavior for managing CHD and navigating the adult health system. Rapid qualitative analysis was conducted to develop two structured data matrices displaying themes about the influence of CHD on identity and enablers of patient engagement.

Results: Of 31 patients, 39% were male, 58% were People of Color, and 35% had prior gaps in care (of 3 or more years). Five domains (from 15 themes) emerged to characterize how patients viewed CHD as influencing their ability to engage with care. Themes included 4 Illness Identity domains (Rejection, Acceptance, Engulfment, and Enrichment) and a fifth domain of Indifference - characterized by a lack of emotional valence that accompanies the other four domains. Variance in these domains could be tracked to differences in patient outcomes, such as perceived ability to navigate the healthcare system (Figure 1). Providers and patients demonstrated concordance regarding the perceived influence of illness domains on patients’ mental health but less concordance regarding its impact on patient engagement and healthcare navigation.

Conclusion: Considering the extent to which a patient views their CHD as a component of their identity could help providers support adult CHD patient engagement, tailor counseling about care guidelines, and likely enhance the effectiveness of patient-provider relationships.