(72) Contemporary Trends of Biologic and Synthetic Conduits for RVOT Reconstruction between 2016-2024: COSMOS-Epic Analysis

Background: Right ventricle outflow tract (RVOT) reconstruction using a right ventricle-to-pulmonary artery (RV-PA) conduit is essential for treating congenital heart diseases like tetralogy of Fallot (TOF) and hypoplastic left heart syndrome (HLHS). Conduit options include biologic (homografts, allografts, xenografts) or synthetic (Gore-Tex, Dacron). While synthetic conduits have gained popularity, much of the supporting evidence originates from studies conducted outside the United States (US). The ideal conduit remains unclear, particularly across patient age and primary cardiac diagnosis.

Objectives: To assess US trends in biologic and synthetic conduit use based on age, race, primary cardiac diagnosis, and region, and evaluate surgical outcomes in patients < 1 year old.

Design/Methods: A retrospective cohort study using Epic’s Cosmos database, a nationally representative, de-identified electronic health records database, was used to examine patients who received an RV-PA conduit between 2016-2024. Patients were grouped according to conduit type: biologic (n = 2194) or synthetic (n = 1211). Kaplan-Meier curves were used to perform survival analyses, and patient characteristics were compared using the 𝜒2 test.

Results: Annual trends in conduit selection showed variable preferences between biologic and synthetic grafts from 2016-2024. Synthetic use increased between 2018–2020, but recent years show a preference towards biologics, historically the gold standard. Conduit choice varied by diagnosis: in TOF, 47.2% received biologic and 18.4% synthetic (p < 0.01); in HLHS, 2.5% biologic and 47.7% synthetic (p < 0.01); in truncus arteriosus, 17.9% biologic and 7.0% synthetic (p=0.03). TGA, PA, and DORV showed similar use across conduit types. Overall freedom from conduit replacement (FCR) was 99% at 2 and 8 years for biologics and 98% and 96% for synthetics. Of this cohort, a majority were < 1 year old, 42.34% (n = 929) of biologics and 68.19% (n = 1211) of synthetics. FCR at 2 and 8 years was 98% and 92%, respectively, for biologics and 97% and 94% for synthetics.

Conclusions: Conduit choice remains a heavily contested and institution-specific decision, but recent trends show renewed preference for biologics. In patients < 1 year old at implantation, biologic conduits showed better early outcomes, but synthetic conduits demonstrated longer durability. Further research is necessary to develop more robust, evidence-based guidelines for conduit selection in this high risk population.