Late outcomes of Fontan operation from the EUROFONTAN experience

Abstract Background Fifty years after the first Fontan operation, the persisting challenges and evolving landscape of post-Fontan complications are explored in the EUROFONTAN experience. Aim of the study is the evaluation of long term outcomes of a large cohort of Fontan patients, focusing on age at Fontan and onset of Fontan-associated liver disease (FALD). Methods A retrospective clinical study across 21 european congenital cardiac centers across Europe. Clinical and operative data of patients who underwent Fontan operation between January 1990 and December 2022 were gathered through a RedCap online database. Results 2606 patients were included in this analysis (M/F: 59%/41%, median age and median weight at Fontan of 4.3 y.o (IQR 3.3-6.4), and 16kg (IQR 14-20), respectively. Most frequent cardiac anomaly were tricuspid atresia and pulmonary atresia with intact ventricular septum (781, 30%). Ventricular morphology was left in 1379 patients (53%), and right in 1029 patients (40%). Extra cardiac conduit (ECC) was performed in the majority of patients (2335, 90%), with a median conduit size of 20mm (IQR 18-20). Early post-operative complications were present in 52% (1340), with an early reintervention in 349 patients (249 surgical , 99 catheter driven) At a median follow-up median of 10 years (IQR 4-15), there were 79 late deaths (3%). Adverse events occurred in 49% (1288 , non-surgical in 962 , surgical in 249). The clinical status was stage A in 60% (1288 patients), while only a minority (1.3%) was in status D. Systemic Ventricular function was normal in 1898 patients (73%), while absent or mild Atrioventricular Valve regurgitation was presnet in 86% (1816). Of note, FALD was detected in 388 (15 %) , and sinus rhythm was present in 99%. Statistical analysis shows that late death and adverse events are significantly associated right ventricular morphology of the systemic ventricle (p-value 0.019). Of note, when compared to lateral tunnel, TCPC extracardiac conduit demonstrated lower late mortality (2.3% vs 8.2%, p-value <0.001) and complication rates (60% vs 48%, p-value 0.001). Analyzing age at Fontan, a linear relationship exists between age and late mortality, whereby mortality increases with advancing age (graph 1). However, concerning the development of late adverse events, the risk decreases with age at Fontan up to 7 years; beyond 7 years, the risk increases with advancing age (graph 2). The analysis demonstrated growing FALD-prevalence with increasing time from Fontan completion (significant especially after 10 years). Conclusion current long term outcomes of Fontan operation are highly satisfactory. However, the longer survival is associated to an increasing incidence of late term extracardiac complications (namely FALD) which are more evident if Fontan is performed at older age.Data of Fontan PatientsCorrelation between age at Fontan and AE