Clinical results of percutaneous closure of large secundum atrial septal defects in children using the Amplatzer septal occluder. 
We reviewed our experience using the Amplatzer septal occluder (AGA Medical, Golden Valley, MN, USA) to close large, secundum-type atrial septal defects (ASDs) in children.  Between June 2002 and December 2005, 52 patients (mean age 13.5 +/- 8.7 years) underwent transcatheter closure of large (> or =25 mm), secundum ASDs with the use of the Amplatzer septal occluder (ASO).  Groups 1 and 2 included patients with a retroaortic rim of <5 mm (n = 39) or > or =5 mm (n = 13), respectively.  All procedures were performed with general anesthesia and transesophageal echocardiographic guidance except for 10 patients, which involved local anesthesia and three-dimensional transthoracic echocardiography.  Successful device implantations, device sizes, approaches, complications, and closure rates were assessed.  Device implantation was successful in 50 patients (96.1%), with no difference between groups (95% vs 100%, P>0.05).  In 2 patients, implantation failed because of embolism or deployment failure.  Device were larger in group 1 than in group 2 (29.7 +/- 4.2 vs 26.7 +/- 3.8 mm, P = 0.04).  The right upper pulmonary-vein approach was more common in group 1 than in group 2 (P = 0.0001).  Complications and closure rates did not differ between the groups (P > 0.05).  Transcatheter closure of large, secundum ASD by using the ASO device was feasible, and complication rates were low.  A deficient retroaortic rim did not preclude successful device implantation; however, a large device may be needed to close large ASD.  Close long-term follow-up is necessary to determine the safety of transcatheter closure of large ASDs in children.