Patent Foramen Ovale-Induced Platypnea-Orthodeoxia Syndrome: A Case Report and Literature Review.

Platypnea-orthodeoxia syndrome (POS) is a rare condition characterized by dyspnea and hypoxia worsening in the upright position and relieved in the recumbent position. POS can result from anatomical or functional conditions that cause interatrial communication or deformity of the atrial septum. Investigations with imaging and cardiac catheterization can aid in the evaluation. In cases where POS is caused by intracardiac shunting without pulmonary hypertension, closure of the intracardiac shunt can be curative. We report a case of POS in a 54-year-old male who was treated successfully with percutaneous closure of a patent foramen ovale (PFO).