Imaging of adult atrial septal defects with CT angiography.

ATRIAL SEPTAL DEFECTS (ASD) ACCOUNT FOR 5% TO 10% OF ALL CASES OF CONGENITAL heart disease and as many as 30% of cases of congenital heart disease presenting in adulthood. These defects make up a spectrum of interesting and distinct entities. The ostium secundum ASD accounts for 70% to 80% of all adult ASDs. Other less common forms of adult ASDs include ostium primum ASD (15% of ASDs), sinus venosus ASD (10% of ASDs), and the unroofed coronary sinus (<1% of ASDs) (1). The complex anatomy of the heart may make differentiation of type, size, and extent of an ASD difficult. The modern post-processing techniques of computed tomography angiography (CTA) are ideally suited for such complicated anatomy and pathology. The type, size, and extent of ASDs can be exquisitely discerned with CTA. Our aim is to provide a practical and image-based resource for review of ASDs in adults, including the rarer variations (Figs. 1 to 7).