When hypoxemia does not respond to oxygen therapy: a case of platypnea-orthodeoxia syndrome

Alba Bermúdez-Jiménez, Department of Cardiology, Hospital Universitario Arnau de Vilanova, Lleida, Spain
Carlos Izurieta, Department of Cardiology, Hospital Universitario Arnau de Vilanova, Lleida, Spain
Marcos García-Guimarães, Department of Cardiology, Hospital Universitario Arnau de Vilanova; Instituto de Investigación Biomédica de Lleida (IRBLleida), Lleida, Spain
Albina Aldomà, Department of Cardiology, Hospital Universitario Arnau de Vilanova, Lleida, Spain
Juan M. Casanova-Sandoval, Department of Cardiology, Hospital Universitario Arnau de Vilanova, Lleida, Spain

Platypnea-orthodeoxia syndrome (POS) is a rare clinical entity characterized by the onset of dyspnea and hypoxemia that normally manifests in the upright position, improving with recumbency. POS is generally caused by both anatomical and functional defects that lead to a right-to-left shunt. Herein, we present an illustrative case of POS in an elderly patient admitted for severe hypoxemia, in which a massive right-to-left shunt through a patent foramen ovale facilitated by an anatomic disturbance was found. Percutaneous closure of the defect was performed, thus correcting the POS.

Keywords: Platypnea-orthodeoxia syndrome. Patent foramen ovale.