Challenges encountered during closure of atrial septal defects.

Since the introduction of transcatheter interventional occlusion of atrial septal defects (ASDs) by King and coworkers, the device closure has become the standard treatment of selected atrial defects. Although it has become routine for standard clinical practice, increasing knowledge of intracardiac anatomy, modification of implantation techniques, and improvements in device designs are making this treatment modality increasingly applicable to a wider range of selected patients. This report summarizes the current trends in patient selection, focusing on the anatomical limits of applicability for ASD device closure, and discusses the future possibilities. Furthermore, typical complications are described with regard to the rare erosion of the atrial roof or the aortic root. Current practice is to oversize the device if the anterior rim toward the aorta tends to be diminutive, achieving a secure position of the device around the aortic root. This and the shape memory of the device may play a major role in this serious complication and should be reconsidered. Although most interventional occlusions of interatrial defects with a device have become clinically routine, some situations remain highly challenging.