CMAJ Practice CME Cases Cardiac platypnea-orthodeoxia syndrome in a 73-year-old woman Khai-Jing Ng MD, Yi-Da Li MD 73-year-old woman was admitted and aorta were 99.7%, 85.5% and 88.6%, Competing interests: None because of progressive shortness of respectively, which is compatible with the pres- declared. A breath over the previous two weeks, ence of intracardiac right-to-left shunt through a This article has been peer which affected her daily activities. She had a patent foramen ovale. We diagnosed platypnea- reviewed. history of congestive heart failure (New York orthodeoxia syndrome. The authors have obtained Heart Association functional class II), hyper- The patient was scheduled for transfer to a patient consent. tension and scoliosis. Her medications included tertiary care centre for further surgical interven- Correspondence to: acetylsalicylic acid, amiloride, hydrochlorothia- tion. Because her oxygen saturation fluctuated Yi-Da Li, zide, atenolol, rosuvastatin and spironolactone. between 80%–90% in the supine position, we
[email protected] She had no orthopnea or productive cough. On questioned whether she would be able to tolerate CMAJ 2015. DOI:10.1503 physical examination, her heart sounds were the three-hour journey. Considering the patho- /cmaj.141525 normal, without murmur. An electrocardiogram physiology of platypnea-orthodeoxia syndrome, showed normal sinus rhythm. we attempted to increase left ventricular end- During the patient’s stay in hospital, intermit- diastolic pressure using a vasopressor to improve tent hypoxemia was noted when she was eating right-to-left shunting. We initially used low-dose or sitting upright; hypoxemia improved when the dopamine (5 μg/kg per min).