Is balloon sizing still necessary in the era of real-time 3D transesophageal echocardiography?

Transcatheter closure of secundum type atrial septal defects (ASD) has become a safe and effective method. However, various technical differences exist during selection of device size in between centers performing transcatheter ASD closure like balloon sizing, and echocardiographic guidance using transoesophageal (TEE), 3-dimensional (3D) and intracardiac echocardiography (ICE). However, there has been no international consensus regarding defect sizing issue.