Timing of Balloon Atrial Septostomy in Hybrid Stage 1 Palliation in Hypoplastic Left Heart Syndrome.

Background: The optimal timing of a balloon atrial septostomy (BAS) in patients with hypoplastic left heart syndrome (HLHS) undergoing hybrid stage 1 (HS1) palliation is unknown. We hypothesized that concomitant completion of the BAS and HS1 would decrease hospital stay, increase intensive care unit-free days, improve hemodynamic markers, and increase transplant-free survival. Methods: We retrospectively reviewed HLHS patients palliated with HS1 from January 2009 to July 2022 at our center. We excluded other single ventricle variants, those who did not have a BAS or had a BAS performed prior to the HS1, and those with an initial atrial septal intervention other than BAS. Patients were divided into 2 groups: (1) those with same-day BAS and HS1, and (2) BAS performed ≥1 day after the HS1. Results: Twenty patients had a BAS and HS1 on the same day, and 69 patients had delayed BAS, whereas 29 patients were excluded. The same-day cohort had significantly shorter hospital length of stay, higher recorded cerebral near infrared spectroscopy troughs, and lower 30-day post-BAS/discharge brain natriuretic peptide levels. There was no difference in transplant-free survival, and a greater proportion of the same-day group required atrial septal reintervention. Conclusions: Although there was no difference in transplant-free survival and higher rates of atrial septal reintervention, concomitant completion of BAS and HS1 in HLHS patients demonstrated shorter HS1 hospitalization and improved hemodynamic markers.