title: Cardiac platypnea-orthodeoxia syndrome induced by a low-volume state.
abstract: We present the case of a 85-year-old patient admitted with palpitations and dyspnea. When assuming a recumbent position, we noticed a significant improvement in dyspnea, as well as a rise in arterial oxygen saturation. This is a typical presentation of platypnea-orthodeoxia syndrome (POS). The diagnosis was confirmed by serial analyses of the arterial oxygen saturation in different positions. In our patient, POS was caused by a cardiac right-left shunt through a patent foramen ovale, facilitated by an atrial septal aneurysm, a dilated aortic root and a large Eustachian valve. A low-volume state, caused by diarrhea and worsened by administration of diuretics in the emergency room, triggered the POS to become clinically apparent. We also noticed a rise in arterial oxygen saturation when the patient was in a hypertensive state. This has never been described before and underlines the influence of hemodynamic changes on the right-left shunt that underlies POS.
authors.affiliation: a Department of Cardiology , Ghent University Hospital , Ghent , Belgium.
authors.forename: Pieter
authors.initials: P
authors.lastname: Ghijselinck
authors.affiliation: b Department of Endocrinology , AZ Delta , Roeselare-Menen , Belgium.
authors.forename: Jan
authors.initials: J
authors.lastname: Van den Saffele
authors.affiliation: c Department of Cardiology , AZ Delta , Roeselare-Menen , Belgium.
authors.forename: Geert
authors.initials: G
authors.lastname: Hollanders
mesh_terms: D000369:Aged, 80 and over; D000783:Aneurysm / Q000150:complications / Q000503:physiopathology*; D001013:Aorta, Thoracic; D001018:Aortic Diseases / Q000150:complications / Q000503:physiopathology*; D054087:Atrial Septum; D003967:Diarrhea / Q000150:complications; D004108:Dilatation, Pathologic / Q000150:complications / Q000503:physiopathology; D004232:Diuretics / Q000009:adverse effects; D004417:Dyspnea / Q000209:etiology / Q000503:physiopathology*; D005260:Female; D054092:Foramen Ovale, Patent / Q000150:complications / Q000503:physiopathology*; D006331:Heart Diseases / Q000150:complications / Q000503:physiopathology*; D006801:Humans; D020896:Hypovolemia / Q000150:complications / Q000503:physiopathology*; D000860:Hypoxia / Q000209:etiology / Q000503:physiopathology*; D011187:Posture; D013577:Syndrome
chemical_list: D004232:Diuretics
keywords: Aortic root dilatation; Atrial septal aneurysm; Intracardiac shunts; Patent foramen ovale; Platypnea