Risk Factors for Adverse Outcomes in a Fontan Population

Improved survival following Fontan surgery is tempered by late Fontan failure. Heterogeneous multi-organ complications contribute to eventual Fontan failure varying over time. The prevalence of Fontan-related complications and their association with adverse outcomes were evaluated. A Fontan cohort of 668 pediatric (n = 490) and adult (n = 178) patients from two healthcare systems were linked to 2010-2019 healthcare encounters and death certificates. Bivariate analyses examined covariates by the primary composite outcome of heart transplant, hepatocellular carcinoma (HCC) or death. Multivariate logistic regression explored associations of risk factors with the primary composite outcome and a secondary outcome of hospitalization. Kaplan-Meier curves compared freedom from the primary composite outcome stratified by number of concurrent risk factors at initial encounter. Of 668 Fontan patients, 12.3% developed the primary composite outcome (21.3% adults, 9.0% children). Clinical risk factors increased with age and time, and were significantly associated with HCC, a component of the primary outcome. Patients with 3 + risk factors had significantly worse survival (log-rank p < 0.01). Heart failure (HF) was the strongest independent predictor of outcomes (aOR 5.90, p < 0.01). Dysrhythmia, cyanosis, and HF were associated with more hospitalizations. The primary composite outcome was 4-fold higher with 3 + risk factors (aOR 3.71, 95% CI 2.26-6.16), significant in children (aOR 3.01, 95% CI 1.17-7.0), and adults (aOR 2.58, 95% CI 1.04-7.48). Complications increase as Fontan patients age and are associated with transplant, HCC, death, and hospitalizations in a pediatric and adult cohort. Early identification and intervention for Fontan-related complications may improve late outcomes.