This study reviewed the short-term outcome of transcatheter closure of the defects within the oval fossa using an Amplatzer® Septal Occluder. From January 1997 to December 2000, 210 patients with defects within the oval fossa underwent successful transcatheter closure. We reviewed a total of 190 patients with left-to-right shunts, assessing the patients for possible complications and the presence of residual shunts using transthoracic echocardiogram at 24 h, 1 month, 3 months and one year. Their median age was 10 years, with a range from 2 to 64 years, and their median weight was 23.9 kg, with a range from 8.9 to 79 kg. In 5 patients, a patent arterial duct was closed, and in 2 pulmonary balloon valvoplasty performed, at the same sitting. The median size of the Amplatzer® device used was 20 mm, with a range from 9 to 36 mm. The median times for the procedure and fluoroscopy were 95 min, with a range from 30 to 210 min, and 18.4 min, with a range from 5 to 144 min, respectively. Mean follow-up was 20.8 ± 12.4 months. Complete occlusion was obtained in 168 of 190 (88%) patients at 24 h, 128 of 133 (96.2%) at 3 months, and 103 of 104 (99%) at one year. Complications occurred in 4 (2.1%) patients. In one, the device became detached, in the second the device embolized into the right ventricular outflow tract, the lower end of the device straddled in the third, and the final patient had significant bleeding from the site of venupuncture. There were no major complications noted on follow-up. We conclude that transcatheter closure of defects within the oval fossa using the Amplatzer® Septal Occluder is safe and effective. Long-term follow-up is required, nonetheless, before it is recommended as a standard procedure.