Abstract
A case of an 85-year-old woman with gradually progressive but severe dyspnea is reported. A thorough workup disclosed platypnea-orthodeoxia syndrome associated with right-to-left shunting through a patent foramen ovale, in the presence of several other recognized risk factors, despite the absence of significant pulmonary hypertension. Successful percutaneous transcatheter closure of the intracardiac defect resulted in resolution of the syndrome.