Transcatheter Closure of Very Large ( ≥ 25 mm) Atrial Septal Defects Using the Amplatzer Septal Occluder Bhava Ramalingam Jawahar Kannan, MD, Edwin Francis, MD, Kothandam Sivakumar, MD, Sivadasan Radha Anil, MD, and Raman Krishna Kumar, * MD Between June 1999 and September 2002, 45 patients (age, 34  13 years; mean shunt ratio, 2.6  0.6) underwent transcatheter atrial septal defect (ASD) closure at our insti- tution with the Amplatzer septal occluder (mean device size, 31.4  3 mm). Patients were selected by transesophageal echocardiography. The mean ASD dimension was 25.3  3.7 mm and 33 (73%) patients had deficient anterior rim. Specific procedural details included the use of 13 or 14 Fr introducer sheaths and the right upper pulmonary vein approach if the conventional approach failed. There were two procedural failures, with device embolization in both (surgical retrieval in one, catheter retrieval in one). During follow-up (3–30 months; median, 16 months), one patient (59 years) with previous atrial flutter had pulmonary embolism and was managed with anticoagulation. Two patients developed symptomatic atrial flutter. Fluoroscopy time was 31.6  19.5 min for the first 22 cases and 19.6  11.4 min for the rest (P  0.04). Transcatheter closure of large ASDs is technically feasible but careful long-term follow-up is needed to document its safety. Cathet Cardiovasc Intervent 2003;59:522–527. © 2003 Wiley-Liss, Inc. Key words: congenital heart disease; catheter interventions INTRODUCTION The atrial septal defect (ASD) represents about 10% of all congenital cardiac anomalies [1]. The closure of ASD with large left-to-right shunt is considered nec- essary to prevent the development of pulmonary vas- cular disease and atrial arrhythmias and the benefit has been shown even in patients older than 40 years [2]. The development of devices for transcatheter closure of ASD located in the fossa ovalis region represents an important advance in catheter-based management of congenital heart disease. Adequate rim of septal tissue around the defect is considered to be necessary to hold the device in position. Previous reports have demon- strated that transcatheter closure is safe and easy to use with a high success rate in small to moderate-sized defects [3– 6]. Defects that stretch to dimensions of 25 mm or more are extremely difficult to close with all available devices other than Amplatzer septal occluder (ASO; AGA Medical, MN) and it can be technically challenging even with ASO. Because of its unique self-centering design, the ASO requires less atrial sep- tal tissue around the ASD for its stability. We report our experience in the closure of large defects that stretched to  25 mm, using ASO. The report will focus on patient selection, technique, and immediate and short-term follow-up results. MATERIALS AND METHODS Study Design This was a retrospective study. We reviewed the records of all patients who underwent transcatheter clo- sure of ASD at our institution between June 1999 and September 2002. Patients with large ASD, defined as those defects with a balloon-stretched diameter of at least 25 mm, were chosen for this report. Patient Population Patients referred for ASD closure were screened for suitability for closure with ASO. After evaluation by transthoracic echocardiography (TTE), all patients un- derwent transesophageal echocardiography (TEE) for complete assessment of the defect, its margins, pulmo- nary venous drainage and for additional defects. Patients Department of Pediatric Cardiology, Amrita Institute of Medical Sciences, Kochi, Kerala, India *Correspondence to: Raman Krishna Kumar, Amrita Institute of Med- ical Sciences and Research Centre, Elamakkara PO, Kochi, 682026, Kerala, India. E-mail: rkrishnakumar@aimshospital.org Received 7 November 2002; Revision accepted 8 April 2003 DOI 10.1002/ccd.10575 Published online in Wiley InterScience (www.interscience.wiley.com). Catheterization and Cardiovascular Interventions 59:522–527 (2003) © 2003 Wiley-Liss, Inc.