Characteristics and outcomes of neonatal balloon atrial septostomy for transposition of the great vessels: ORA – TGV study

Balloon atrial septostomy (BAS) improves oxygenation in neonates with Transposition of the Great Vessels (TGV). New non-EC marked BAS catheters have obtained temporary approval in France. We aim to investigate outcomes of neonatal BAS in the current area. An on-going multi-center French prospective observational registry was set up in September 2022 including all neonates undergoing BAS for TGV. To date, 60 neonates (93.5% of term-babies, weight: 3.1 [2.8–3.4] Kg, prenatal diagnosis: 88.5%, isolated form of TGV: 68.9%) underwent 62 BAS (50% on general anaesthesia) in 14 participating centres. The procedure was performed over night or during weekend in 39.3% of cases. BAS was performed most often the day of birth (65.6%), in the catheter lab (59%) using an umbilical venous route (67.2%). The latter required conversion to a femoral route in 22.0% of patients. BAS was guided by ultrasounds and fluoroscopy in 90.2% and 55.7% of cases, respectively. Two to 4 BAS manoeuvre were required in 82.0% of cases. In 14.8% of patients, the use of a second type of BAS catheter was required. Z5 and Z6 catheters were used in 45.6% and 54.4% of cases, respectively. Overall, BAS was successfully achieved in 93.5% of cases. BAS failures included 3 crossing failures (n = 3) and a failure of enlargement of the atrial septum with a low-volume Z5 catheter (n = 1). One transient complete atrio-ventricular block was also reported. To date, BAS success rate seems lower than expected. The continuation of this study and its expected European extension will likely contribute to clarify these points in a context of world shortage in dedicated low profile/high volume catheters.