In their editorial review in this issue of the Journal, Stephens and Dearani1 comment on the results of our retrospective series2 that assessed the incidence and impact of atrioventricular regurgitation in patients who had survived the Fontan operation. In our experience, more than half of the common atrioventricular valves and tricuspid valves were regurgitant or necessitated intervention before patients reached the age of 25 years (Figure 1).2 The existence of even moderate regurgitation was enough to more than double a patient's risk of circulatory failure, which for most meant death or transplantation.
