Orthodeoxia Platypnea Syndrome in the Setting of Cholangiocarcinoma: A Case Report.

Platypnea-orthodeoxia syndrome is a rare cause of positional hypoxemia and dyspnea. We present the case of a 54-year-old man with right-to-left shunting through a patent foramen ovale in the setting of metastatic cholangiocarcinoma resulting in platypnea-orthodeoxia syndrome. The shunt was originally not visualized on cardiac magnetic resonance imaging but later detected with transesophageal echocardiography. This case highlights the importance of complimentary multimodality cardiac imaging in the diagnosis of both common and uncommon disorders.