Molecular Pathways and Animal Models of Atrial Septal Defect

The seeming simplicity of the clinical presentation and management of an atrial septal defect belies the complexity of the developmental pathogenesis. Here, we describe the anatomic development of the atrial septum and the venous return to the atrial chambers. Recent experimental results suggest where genetic mutations could disrupt developmental steps to cause a defect within the oval fossa, the so-called secundum defect or other interatrial communication, such as the sinus venosus defect.