Balloon atrial septostomy is a common palliative procedure in neonates with cyanotic congenital heart disease with restricted interatrial blood flow. Despite its advantages, balloon atrial septostomy is not a risk-free procedure and can be associated with numerous complications. The objective of this study is to determine whether the performance of this procedure out-of-hours has a significant impact on the incidence of adverse outcome measures.

A total of 106 neonates who underwent balloon atrial septostomy between 2004 and 2010 were studied retrospectively. In all, 64 infants had the procedure performed within routine hours (9 am to 6 pm), whereas 42 neonates underwent the procedure out-of-hours (6:01 pm to 8:59 am). Procedure-related complications occurred in 32 infants (30.2%), which included 12 out of 64 (18.8%) infants in the routine-hours group and 20 out of 42 (47.6%) in the out-of-hours group. During further follow-up after surgery and including both major and minor adverse events, seven more infants (10.9%) suffered complications after balloon atrial septostomy in the routine-hours group and four more infants (9.5%) suffered complications in the out-of-hours group. This totalled the complication rate in the routine-hours group to 19 infants (29.7%) and 24 infants (57.1%) in the out-of-hours group (p = 0.001). A higher overall mortality rate was also noted in the out-of-hours group.

Balloon atrial septostomy performed out-of-hours produced higher complication rates as opposed to balloon atrial septostomy performed during routine hours. Only essential cases should be undertaken at night, and all other cases should be deferred to the daytime to limit unnecessary adverse complication.