title: Platypnea-orthodeoxia as a cause of unexplained hypoxemia in an 82-yr-old female.
abstract: We describe an 82-yr-old patient with platypnea-orthodeoxia without identifiable lung disease in whom the diagnosis was suspected because of clinical history, echocardiography, and orthostatic measurement of arterial blood gases. Recumbent and upright cardiac catheterization techniques confirmed the presence of orthostatic variation in the degree of right to left shunt across the fossa ovalis. This was successfully treated by surgical closure of the interatrial communication in the region of the fossa ovalis.
authors.affiliation: Division of Cardiology, Loma Linda University Medical Center, California 92350.
authors.forename: S B
authors.initials: SB
authors.lastname: Nazzal
authors.forename: R C
authors.initials: RC
authors.lastname: Bansal
authors.forename: S J
authors.initials: SJ
authors.lastname: Fitzmorris
authors.forename: C A
authors.initials: CA
authors.lastname: Schmidt
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D006328:Cardiac Catheterization; D004562:Electrocardiography; D005260:Female; D006344:Heart Septal Defects, Atrial / Q000150:complications / Q000175:diagnosis* / Q000601:surgery; D006801:Humans; D000860:Hypoxia / Q000209:etiology*; D011187:Posture