Balloon atrial septostomy (BAS), a life saving procedure is reliably effective in infants less than one month of age. Beyond the neonatal period, the septum thickens and may be too tough or too thick for a simple BAS to tear. An atrial septal defect (ASD) may then be created by surgery or using the Park blade septostomy catheter. In this acute study we examine a new method to create an ASD using a Cutting Balloon Catheter (IVT). Under general anaesthesia, young piglets (n=6) weighing 10.9 - 15.1 (mean 11.7) kg had 7 Fr long sheaths placed via a femoral vein and passed to the right atrium. Using a Brockenborough needle through this sheath, the atrial septum was punctured to allow an 0.014" wire to be placed across the atrial septum into the left heart. The needle was removed and replaced by a Cutting Balloon Catheter (2.5 or 4.0 mm diameter) over the wire. Placing the balloon in the left atrium, the balloon was inflated and pulled back, cutting the atrial septum. The cuts created were enlarged using an 8 mm diameter angioplasty catheter. The tear created measured 3 - 8 (mean 4.4) mm. Qp/Qs was calculated to be 1.63/1 (range 1.14 - 2.71). The ASD was demonstrated by 2-D echo and confirmed by pathological examination.

We conclude that the Cutting Balloon Catheter is a new simple and effective method to create ASD in older infants and children.