title: Platypnoea-orthodeoxia syndrome, an underdiagnosed cause of hypoxaemia: four cases and the possible underlying mechanisms.
abstract: Cardiac platypnoea-orthodeoxia syndrome (POS) is a position-dependent condition of dyspnoea and hypoxaemia due to right-to-left shunting. It often remains unrecognised in clinical practice, possibly because of its complex underlying pathophysiology. We present four consecutive patients with POS and patent foramen ovale (PFO) who underwent a successful percutaneous PFO closure, describe the mechanism of their POS and provide a review of the literature.
authors.affiliation: Department of Cardiology, Cardiac Catheterization Laboratory, Academic Medical Center-University of Amsterdam, PO Box 22660, 1100 DD, Amsterdam, The Netherlands. r.j.dewinter@amc.uva.nl.
authors.forename: M
authors.initials: M
authors.lastname: Nassif
authors.affiliation: Department of Cardiology, Cardiac Catheterization Laboratory, Academic Medical Center-University of Amsterdam, PO Box 22660, 1100 DD, Amsterdam, The Netherlands.
authors.forename: H
authors.initials: H
authors.lastname: Lu
authors.affiliation: Department of Cardiology, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: T C
authors.initials: TC
authors.lastname: Konings
authors.affiliation: Department of Cardiology, Cardiac Catheterization Laboratory, Academic Medical Center-University of Amsterdam, PO Box 22660, 1100 DD, Amsterdam, The Netherlands.
authors.forename: B J
authors.initials: BJ
authors.lastname: Bouma
authors.affiliation: Department of Pulmonary Medicine, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: A
authors.initials: A
authors.lastname: Vonk Noordegraaf
authors.affiliation: Department of Cardiology, Cardiac Catheterization Laboratory, Academic Medical Center-University of Amsterdam, PO Box 22660, 1100 DD, Amsterdam, The Netherlands.|Department of Pediatric Cardiology, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: B
authors.initials: B
authors.lastname: Straver
authors.affiliation: Department of Cardiology, Cardiac Catheterization Laboratory, Academic Medical Center-University of Amsterdam, PO Box 22660, 1100 DD, Amsterdam, The Netherlands.|Department of Pediatric Cardiology, Academic Medical Center, Amsterdam, The Netherlands.|Department of Pediatric Cardiology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: N A
authors.initials: NA
authors.lastname: Blom
authors.affiliation: Department of Pediatric Cardiology, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: S A
authors.initials: SA
authors.lastname: Clur
authors.affiliation: Department of Cardiology, Cardiac Catheterization Laboratory, Academic Medical Center-University of Amsterdam, PO Box 22660, 1100 DD, Amsterdam, The Netherlands.
authors.forename: A P C M
authors.initials: AP
authors.lastname: Backx
authors.affiliation: Department of Cardiology, Cardiac Catheterization Laboratory, Academic Medical Center-University of Amsterdam, PO Box 22660, 1100 DD, Amsterdam, The Netherlands.
authors.forename: M
authors.initials: M
authors.lastname: Groenink
authors.affiliation: Department of Cardiology, Cardiac Catheterization Laboratory, Academic Medical Center-University of Amsterdam, PO Box 22660, 1100 DD, Amsterdam, The Netherlands.
authors.forename: S M
authors.initials: SM
authors.lastname: Boekholdt
authors.affiliation: Department of Cardiothoracic Surgery, Academic Medical Center, Amsterdam, The Netherlands.|Department of Pediatric Cardiac Surgery, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: D R
authors.initials: DR
authors.lastname: Koolbergen
authors.affiliation: Department of Cardiothoracic Surgery, Academic Medical Center, Amsterdam, The Netherlands.|Department of Pediatric Cardiac Surgery, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: M G
authors.initials: MG
authors.lastname: Hazekamp
authors.affiliation: Department of Cardiology, Cardiac Catheterization Laboratory, Academic Medical Center-University of Amsterdam, PO Box 22660, 1100 DD, Amsterdam, The Netherlands.|Interuniversity Cardiology Institute of the Netherlands (ICIN), Utrecht, The Netherlands.
authors.forename: B J M
authors.initials: BJ
authors.lastname: Mulder
authors.affiliation: Department of Cardiology, Cardiac Catheterization Laboratory, Academic Medical Center-University of Amsterdam, PO Box 22660, 1100 DD, Amsterdam, The Netherlands.
authors.forename: R J
authors.initials: RJ
authors.lastname: de Winter
keywords: Atrial septum; Dyspnoea; Foramen ovale, patent; Mechanism; Platypnoea-orthodeoxia