Swiss Cheese–Like Atrial Septal Defect

Abstract

Atrial septal defects (ASDs), apart from the bicuspid aortic valve, are the most common congenital heart malformations, and it is not uncommon for them to go undiscovered until a patient reaches adulthood.1 An ostium secundum ASD is the most common septal defect, comprising 75% of all these defects.2 Elective closure should be considered in patients with signs of right heart dilatation and in those who have a presumed paradoxical event.3 In patients with an ostium secundum ASD, percutaneous closure–first reported in 19744—is now well established. Before a percutaneous closure attempt, the suitability of the defect for device implantation should be assessed with transesophageal echocardiography. Associated malformations (eg, partial anomalous pulmonary venous drainage) and the number, location(s), and the dimensions of the defect(s) should be known before the procedure. A defect in the atrial septum can exist when the flap valve derived from the septum primum does not overlap its rim (eg, because of atrial dilation) or because the flap …