Technical challenges of atrial septal stent placement in fetuses with hypoplastic left heart syndrome and intact atrial septum.

OBJECTIVES: The objective of this study was to describe our single-institution experience with prenatal atrial septal stent placement for fetuses with hypoplastic left heart syndrome and an intact atrial septum (HLHS/IAS).

BACKGROUND: Infants born with HLHS/IAS are at high risk for neonatal death, despite maximal postnatal therapy. Prenatal atrial septoplasty by static balloon dilation has been effective in decompressing the left atrium (LA) in utero, but several factors have limited the size of septal defects. We attempted to overcome the limitations of balloon septoplasty using transcatheter atrial septal stents.

METHODS: All records from our institution of fetuses with HLHS/IAS that underwent prenatal atrial septal stent placement were reviewed, including operative notes and echocardiograms.

RESULTS: Nine fetuses between 24 and 31 weeks gestation with HLHS/IAS underwent attempted fetal atrial septal stent placement. A stent was deployed across the atrial septum in five fetuses, with four fetuses demonstrating flow across the stent at the time of intervention. In four cases, stent placement failed due to malposition or embolization, but in three of the four cases, atrial balloon septoplasty at the same in-utero procedure successfully and acutely decompressed the LA. There were no maternal complications. There was one fetal demise. The remaining eight fetuses survived to delivery, but four died in the neonatal period (two of which had been stented).

CONCLUSIONS: Ultrasound-guided atrial septal stent placement is feasible in some fetuses with HLHS/IAS. Visualization of the septum and catheter tip is critical to technical success. Additional experience is necessary to determine the clinical impact of this intervention. © 2013 Wiley Periodicals, Inc.