Natural and Modified History of Atrioventricular Valve Regurgitation in Patients With Fontan Circulation

Abstract

BackgroundAtrioventricular valve (AVV) regurgitation is increasingly prevalent in patients with a Fontan circulation. ObjectivesWe sought to determine the impact of ventricular dominance and AVV operation on outcomes in patients with a Fontan circulation and ≥moderate AVV regurgitation. MethodsWe conducted a retrospective study, including propensity score matching analysis, of 1,703 patients who survived Fontan operation in Australia and New Zealand from 1987 to 2021. ResultsPatients undergoing AVV operation were more likely to have right ventricular (RV) dominance or an atrioventricular septal defect. In the entire cohort, death or transplantation after Fontan operation was significantly higher in patients who underwent AVV operation before or at Fontan completion compared with those who did not (20 years: 18%; 95% CI: 8%-26% vs 13%; 95% CI: 10%-15%; P = 0.03). After propensity score matching, including for RV dominance, there was no significant difference in death or transplantation between the groups (20 years: 18%; 95% CI: 8%-26% vs 16%; 95% CI: 10%-22%; P = 0.41). Only patients with RV dominance who developed ≥moderate AVV regurgitation after Fontan operation were at increased risk of death or transplantation (HR: 2.8; 95% CI: 1.4-5.3; P < 0.01). In patients with left ventricular dominance, there was no significant difference in death or transplantation between patients with ≥moderate AVV regurgitation compared with those with <moderate regurgitation (P = 0.8). ConclusionsRV dominance, but not AVV surgery itself, was associated with poor outcomes. Moderate or greater AVV regurgitation after Fontan operation is associated with a significantly increased risk of death or transplantation, only in patients with RV dominance.