Ascending aortic aneurysm and patent foramen ovale: a rare cause of platypnea-orthodeoxia.

Platypnea-orthodeoxia is a rare syndrome characterized by dyspnea and hypoxia induced by the upright position and relieved by the supine position. Several factors related to atrial anatomy can facilitate shunting through an atrial septal defect; in many cases, the syndrome is associated with patent foramen ovale and right-to-left shunt, and has also been linked to aortic aneurysm. We present a case of platypnea-orthodeoxia syndrome in a 61-year-old woman with patent foramen ovale and ascending aortic aneurysm.