Platypnea or platypnoea is shortness of breath (dyspnea) that is relieved when lying down, and worsens when sitting or standing. It is the opposite of orthopnea. The condition was first described in 1949 and named in 1969.
Platypnea and orthodeoxia can co-exist, and this combination is named platypnea-orthodeoxia syndrome. The syndrome is considered extremely rare.
Platypnea is due to either hepatopulmonary syndrome or an anatomical cardiovascular defect increasing positional right-to-left shunting (bloodflow from the right to the left part of the circulatory system) such as a patent foramen ovale. These defects include rare syndromes in which the venous blood from the liver does not pass through the lungs, or if venous blood from the portal circulation reaches the inferior vena cava without passing through the liver (Abernethy malformation, type 1).
Etymology and pronunciation
- Dorland's Illustrated Medical Dictionary (32 ed.). Elsevier Saunders. 2012. p. 1459. ISBN 978-0-8089-2418-0.
- Robin ED, McCauley RF (1997). "An analysis of platypnea-orthodeoxia syndrome including a 'new' therapeutic approach". Chest. 112 (6): 1449–51. doi:10.1378/chest.112.6.1449. PMID 9404736.
- Dorland's Illustrated Medical Dictionary (32 ed.). Elsevier Saunders. 2012. p. 1337. ISBN 978-0-8089-2418-0.
- Cheng TO (2002). "Mechanisms of platypnea-orthodeoxia: what causes water to flow uphill?". Circulation. 105 (6): e47. doi:10.1161/circ.105.6.e47. PMID 11839642.
- Kubler P, Gibbs H, Garrahy P (2000). "Platypnoea-orthodeoxia syndrome". Heart. 83 (2): 221–3. doi:10.1136/heart.83.2.221. PMC 1729301. PMID 10648502.