Alsaied T, et al. - Based on the assumption that increased Fontan baffle stroke volume is associated with increased energy loss in the baffle, researchers investigated if higher baffle stroke volume is related to worse exercise capacity and increased incidence of Fontan failure. In this study, they included patients who had an atriopulmonary or lateral tunnel Fontan operation at 6 centers. Only cases with a cardiac magnetic resonance (CMR) study and an adequate cardiopulmonary exercise test were included. Findings revealed an independent association of larger Fontan baffle stroke volume with lower peak VO₂ and Fontan failure in atriopulmonary Fontan.