The Journal of Tehran University Heart Center79 TEHRAN HEART CENTER Original Article

Background: The transcatheter closure of the atrial septal defect (ASD) has become an alternative technique to surgical procedures. The aim of this study was to assess the immediate, short, and intermediate-term results of the transcatheter closure of the secundum ASD with the Amplatzer Septal Occluder (ASO) in adult Iranian patients. Methods: Between December 2004 and July 2008, the transcatheter closure of the ASD using the ASO was attempted in 58 consecutive, adult patients. The mean age of the patients was 37.1 ± 12.7 years (range = 19- 75 years). All the procedures were performed under local anesthesia with transthoracic or transesophageal echocardiography and fluoroscopic guidance. The stretched diameter of the ASD was determined with a balloon sizing catheter, and device selection was based on and matched to the stretched diameter of the septal defect. Transthoracic echocardiography was performed immediately after the release of the device and before discharge. Further follow-up at one month, six months, and yearly thereafter included physical examination, electrocardiography, and transthoracic echocardiography. Results: The mean ASD diameter, as measured by esophageal echocardiography, was 24.8 ± 5.4 mm (range = 13- 34 mm). The mean stretched diameter, as measured by the balloon catheter, was 27.1 ± 6.4 mm (range = 12.5- 39 mm). Deployment of the ASO was successful in 52 (89.6%) patients and failed in 6 (10.4%). Four patients experienced severe complications