Abstract Body (Do not enter title and authors here): Background: Long-term survival of patients with congenital heart disease (CHD) has increased significantly in the past 40 years, resulting in the largest adult congenital heart disease (ACHD) population in history. Pathologic genetic variation significantly contributes to development, heritability, and outcomes of CHD. International guidelines for genetic testing in syndromic, familial, and complex CHD requiring intervention were published in the last decade and did not address the ACHD population, who was diagnosed well before this era. Perceptions of ACHD patients regarding genetic testing are unknown.

Aims: Assess the proportion of ACHD patients that have received genetic testing compared to those that would be considered for testing based on current recommendations. Assess interest and perceived risks and benefits of genetic testing and how these are impacted by clinical and family factors.

Methods: Single center prospective cohort survey of consecutive ACHD patients 18 years or older seen in outpatient clinics over a 5-month period.

Results: Data were provided by 124 survey respondents, 48.4% female with median age 29.1 years (IQR 23.1-37.8). A majority of respondents (68.3%) have children or plan to have children. Few respondents (10.5%) report prior genetic testing. The majority desire genetic testing (65.3%), while only 8.1% would not choose to have testing performed. Respondents mostly believe testing should occur either during infancy (36.1%) or in adulthood before having children (29.5%). Personal and family health considerations were among the most important motivating factors for consideration of genetic testing, while financial factors were not as prioritized, as shown in Figure 1. Few respondents felt genetic testing would have a negative impact on their mental health (4.2%); the majority felt there would be a positive (53.3%) or neutral (42.5%) effect.

Conclusions: Many ACHD patients would have received genetic testing if born in the current era, but very few have been offered such testing given a lack of recommendations in the ACHD population. Broadening genetic evaluation for the adult CHD population should be considered given patient interest and current pediatric CHD recommendations.