Preserved Antegrade Pulmonary Blood Flow in Bidirectional Glenn: Outcomes and Considerations for Staged Palliation.

Abstract

Preservation of antegrade pulmonary blood flow (APBF) at the time of bidirectional Glenn (BDG) is believed to promote pulmonary artery growth and prevent pulmonary arteriovenous fistulas. However, its clinical impact on early and midterm outcomes remains unclear. This study aimed to evaluate the impact of APBF preservation on early and midterm outcomes. This single-center retrospective study included 47 patients who underwent BDG between 2017 and 2025. Patients were categorized by APBF status: eliminated APBF (APBF-; n = 30) or preserved APBF (APBF+; n = 17). Early and midterm outcomes and hemodynamic changes between BDG and pre-Fontan evaluations were compared. In early postoperative outcomes, the APBF+ group had significantly longer mechanical ventilation (0 days vs 1 day; P = .03). At the pre-Fontan evaluation, no significant differences were observed in pulmonary artery index or arterial oxygen saturation. However, the APBF+ group showed a significantly higher pulmonary-to-systemic blood flow ratio (0.64 vs 0.82; P = .004), and higher brain natriuretic peptide values (15.16 pg/mL vs 26.02 pg/mL; P = .05). Regarding midterm outcomes, atrioventricular valve surgery (3.3% vs 17.6%; P = .13) and interventions for venovenous collateral vessels (4.5% vs 30.0%; P = .08) tended to be more frequent in the APBF+ group. No pulmonary arteriovenous fistula interventions were required in either group. Fontan completion and survival were comparable. No group × time interaction was found in hemodynamic changes. Preserving APBF did not improve pulmonary artery development or hemodynamics and was associated with increased volume load and interstage interventions. Selective rather than routine APBF preservation is recommended.