title: Platypnea-orthodeoxia syndrome in the elderly treated by percutaneous patent foramen ovale closure: a case series and literature review.
abstract: BACKGROUND
  Platypnea-orthodeoxia syndrome (POS) is a rare clinical phenomenon, associating normal oxygen saturation in a supine position and arterial hypoxemia in an upright position. This pathology can be secondary to an intracardiac shunt, a pulmonary vascular shunt or a ventilation-perfusion mismatch. Cardiac POS occurs in the presence of a right-to-left cardiac shunt, most commonly through a patent foramen ovale (PFO).
  
  
  RESULTS
  From our single-center prospective database of percutaneous PFO closure we identified five patients (4 females, mean age: 77 ± 11 years) out of 224 (2.2%) patients with a PFO who presented with a POS of cardiac origin. Transthoracic and transoesophageal echocardiographic examinations revealed the underlying mechanisms of POS and the diagnosis was confirmed by right-and-left cardiac catheterization (RLC) and by measuring serial blood oxygen saturation in the pulmonary veins and left atrium in supine and upright positions. PFO was associated with atrial septal aneurysm and a persistent prominent Eustachian valve in 3 patients. All patients underwent a successful percutaneous PFO closure without any immediate or subsequent complications (mean follow-up of 24 ± 18 months). Immediately after the procedure, mean arterial oxygen saturation improved from 83% ± 3 to 93% ± 2 in an upright position and symptoms disappeared.
  
  
  CONCLUSIONS
  POS is a rare and under-diagnosed pathology that must be actively investigated in the presence of position-dependent hypoxemia. The diagnostic work-up must exclude other causes of hypoxemia and confirm the intracardiac shunt using either contrast echocardiography or RLC. For cardiac POS, percutaneous PFO closure is a safe and effective technique that immediately relieves orthodeoxia and patient symptoms.
authors.affiliation: Cardiology Division, University Hospital, Geneva, Switzerland.
authors.forename: Coralie
authors.initials: C
authors.lastname: Blanche
authors.forename: Stéphane
authors.initials: S
authors.lastname: Noble
authors.forename: Marco
authors.initials: M
authors.lastname: Roffi
authors.forename: Ariane
authors.initials: A
authors.lastname: Testuz
authors.forename: Hajo
authors.initials: H
authors.lastname: Müller
authors.forename: Philippe
authors.initials: P
authors.lastname: Meyer
authors.forename: John M
authors.initials: JM
authors.lastname: Bonvini
authors.forename: Robert F
authors.initials: RF
authors.lastname: Bonvini
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000783:Aneurysm / Q000150:complications; D006328:Cardiac Catheterization; D016208:Databases, Factual; D004417:Dyspnea / Q000209:etiology / Q000601:surgery*; D005260:Female; D054092:Foramen Ovale, Patent / Q000150:complications / Q000175:diagnosis / Q000601:surgery*; D006344:Heart Septal Defects, Atrial / Q000150:complications; D006801:Humans; D000860:Hypoxia / Q000209:etiology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D011187:Posture; D011446:Prospective Studies; D016683:Supine Position; D013577:Syndrome
keywords: Cardiac platypnea–orthodeoxia syndrome; Patent foramen ovale; Percutaneous closure