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Published on: November 18, 2018
Platypnea Orthodeoxia Syndrome Secondary to a Persistent Eustachian Valve
Poonam Rao1, Chaitanya Undavalli1, Mohamed Ghoweba2
1Internal Medicine, CHRISTUS Health/Texas A&M School of Medicine Internal Medicine Residency Program, Longview, USA.
Abstract:
Platypnea-Orthodeoxia syndrome (POS) is a rare and poorly understood syndrome characterized by platypnea and oxygen desaturation in the upright position that is relieved by recumbency. Here, we report a case of an 84-year-old woman who had chronic hypoxia in an upright position despite using home oxygen. The patient presented for hypoxia evaluation and was noted to have a restrictive pattern on pulmonary function tests (PFT). An echocardiogram showed a prominent eustachian valve extending from inferior to superior vena cava with contrast approaching the interatrial septum. The patient had a complete resolution of her platypnea following the closure of the patent foramen ovale.
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