Does leaving native antegrade pulmonary blood flow at the time of the superior cavopulmonary connection impact long-term outcomes after the Fontan?

Objectives: Antegrade pulmonary blood flow (APBF) may be left or eliminated at the time of the superior cavopulmonary connection (SCPC). Our aim was to assess the impact of leaving native APBF at the SCPC on long-term Fontan outcomes.

Methods: In the Australia and New Zealand Fontan Registry (1985-2021), 587 patients had pre-existing native APBF at the SCPC. At the SCPC, 302 patients had APBF eliminated (APBF) and 285 patients had APBF maintained (APBF). The incidence of Fontan failure (composite end point of Fontan takedown, transplant, plastic bronchitis, protein losing enteropathy and death) and atrioventricular (AV) valve repair/replacement post SCPC was compared between the 2 groups.

Results: Sex, predominant-ventricle morphology, isomerism, primary diagnosis, and age/type of Fontan were similar between groups. APBF versus APBF had a higher incidence of arch obstruction/coarctation (17% vs 7%) and previous pulmonary artery band (54% vs 45%) and a lower rate of Fontan fenestration (27% vs 41%). The risk of Fontan failure was similar between the 2 groups (hazard ratio [HR], 1.01; 95% confidence interval [CI], 0.58-1.78;  = .96). The risk of AV-valve repair/replacement was greater in APBF versus APBF- (HR, 2.32; CI, 1.13-4.75;  = .022). The risk of AV-valve repair/replacement remained after adjustment for arch obstruction/coarctation, previous pulmonary artery band and Fontan fenestration (HR, 2.27; CI, 1.07-4.81;  = .033).

Conclusions: Maintaining APBF at the time of the SCPC does not impact the risk of Fontan failure but may increase the incidence of AV-valve repair and/or replacement post-SCPC.