title: A case of platypnea-orthodeoxia syndrome in a patient with a pulmonary arteriovenous fistula and a patent foramen ovale.
abstract: We describe a case of a rare clinical disorder, platypnea-orthodeoxia syndrome. A 57-year-old man was admitted with progressive dyspnea. While breathing room air, arterial oxygen saturation decreased from 92% in a recumbent position to 83% in an upright position. Transthoracic echocardiography revealed normal left and right ventricular function, but intravenous infusion of air-blood-saline resulted in the appearance of microbubbles in the left side of the heart, indicating the presence of right-to-left shunt. Transesophageal echocardiography demonstrated a small amount of right-to-left shunting through a patent foramen ovale. Further, the left lower pulmonary vein was dilated, and contrast echocardiography revealed drainage of microbubbles mainly from the left lower pulmonary vein. A pulmonary angiogram revealed the presence of a pulmonary arteriovenous fistula. The patient underwent embolization of the arteriovenous fistula with subsequent resolution of dyspnea and hypoxemia. Platypnea-orthodeoxia syndrome is rare, and patients with this syndrome require an extensive workup to determine its cause.
authors.affiliation: Cardiovascular Division, National Cardiovascular Center, Osaka, Japan. tkohara@hsp.ncvc.go.jp <tkohara@hsp.ncvc.go.jp>
authors.forename: Takahiro
authors.initials: T
authors.lastname: Ohara
authors.forename: Satoshi
authors.initials: S
authors.lastname: Nakatani
authors.forename: Shuji
authors.initials: S
authors.lastname: Hashimoto
authors.forename: Yasuhisa
authors.initials: Y
authors.lastname: Akaiwa
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yazaki
authors.forename: Koji
authors.initials: K
authors.lastname: Kimura
authors.forename: Izuru
authors.initials: I
authors.lastname: Nakasone
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Masuda
authors.forename: Hideaki
authors.initials: H
authors.lastname: Kanzaki
authors.forename: Masafumi
authors.initials: M
authors.lastname: Kitakaze
mesh_terms: D000792:Angiography; D001164:Arteriovenous Fistula / Q000150:complications* / Q000175:diagnosis / Q000628:therapy; D003937:Diagnosis, Differential; D004417:Dyspnea / Q000175:diagnosis / Q000209:etiology*; D017548:Echocardiography, Transesophageal; D004621:Embolization, Therapeutic / Q000379:methods; D005500:Follow-Up Studies; D006344:Heart Septal Defects, Atrial / Q000150:complications* / Q000175:diagnosis; D006801:Humans; D008297:Male; D008875:Middle Aged; D011651:Pulmonary Artery / Q000002:abnormalities*; D011667:Pulmonary Veins / Q000002:abnormalities*; D013577:Syndrome