Moderate or severe atrioventricular valve regurgitation after a Fontan operation raises the risk of death or transplantation, Australian doctors have found, but only in patients with right ventricular dominance.

Results from the retrospective study suggest that patients’ baseline characteristics — namely right ventricular (RV) dominance — rather than atrioventricular valve (AVV) surgery itself are associated with poor outcomes.

Given the “devastating natural history” of the congenital heart disease, researchers say further efforts are needed to develop methods that ensure AVV competence in this setting.

Using data from 1700 patients, clinicians led by the Royal Children’s Hospital in Melbourne explored the impact of ventricular dominance and AVV operation on outcomes in those with a Fontan circulation and moderate or severe AVV regurgitation.