Patent Foramen Ovale and Atrial Septal Defect

Patent Foramen Ovale (PFO) is the most common congenital cardiac abnormality and found in ~25% of all adults. PFO results from the failed closure of the foramen ovale and is associated with an increased risk of stroke in symptomatic patients and recent trials have demonstrated the utility of PFO closure for the prevention of recurrent stroke in patients with cryptogenic stroke and PFO. Imaging plays an important role in determining both the presence of a PFO as well as its suitability for closure in a patient with cryptogenic stroke. Atrial septal defects are the third most common congenital defect (after PFOs and bicuspid aortic valve) but are often asymptomatic until adulthood. Complications of undetected ASDs include arrythmia, paradoxical embolization, cerebral abscess, right ventricular (RV) volume overload with late RV failure, and potentially irreversible pulmonary hypertension. This chapter explores the indications and important imaging features in diagnosis, pre-procedural planning and interventional closure of PFOs and ASDs. The heart team discussion highlights the multifactorial approach regarding surgical vs. percutaneous closure and device choice.