D-14 | Atrial Septal Interventions During and After Hybrid Stage I Palliation

Abstract

Hybrid stage I palliation (HS1P) is an alternative approach for single ventricle (SV) patients, particularly those with high-risk factors. Unlike surgical stage I palliation where atrial septectomy is standardly performed, the approach to atrial septal intervention (ASI) during HS1P is patient dependent. In this study, we aimed to describe the frequency of interventions on the atrial septum both at the time of the HS1P and during the interstage period and to determine factors associated with a need for ASI post-HS1P. A retrospective study was performed in all SV patients who underwent HS1P at our center in the past 12 years. Initial and subsequent interventions on the atrial septum were collected through either surgical Norwood or Comprehensive stage II. Patient factors, atrial septal characteristics by echo, and type of atrial septal intervention were also collected and compared to identify risk factors for ASI intervention post-HS1P. Of 50 SV patients included, about half of the patients (26/50) required an ASI post-HS1P; 23 (46%) had an ASI performed at the time of HS1P, and 7 (27%) of these patients required a subsequent ASI. Of the 27 patients who did not undergo an initial ASI, 19 (70%) required a subsequent ASI. Compared to static and cutting balloon septoplasty, balloon atrial septostomy and atrial septal stent placement were associated with a decreased risk of need for ASI post-HS1P (both p<0.05). There were no significant differences in patient characteristics, hospital course, or overall outcomes between patients who required ASI post-HS1P vs. those who did not. Atrial septal intervention after HS1P is common but has little impact on patient outcomes through the next stage of palliation. Although no patient or anatomic factors were identified risk factors for atrial septal intervention post-HS1P (besides having an intact atrial septum), intervention with either balloon atrial septostomy or atrial septal stent placement was associated with a lower need for atrial septal reintervention and therefore may be the preferred approach when anatomically feasible.