Platypnea-orthodeoxia syndrome in a patient with an ascending aorta aneurysm and an persistent Eustachian valve : A case report

Introduction: Platypnea-orthodeoxia (PO) is a rare syndrome characterized by dyspnea and hypoxemia accompanying a change to a sitting or standing from a recumbent position. The eustachian valve (EV) is a remnant of the embryonic right valve of the sinus venosus. We describe a case of a PO syndrome. Case: A 93-year old woman admitted to the intensive care unit for sepsis, presented an intermittent shunt on arterial blood gases with a positional character. A test with pure oxygen and an intravenous agitated bubble contrast study with transthoracic echocardiography were performed. The gazometric shunt persisted in standing position and under pure oxygen. The echocardiography showed an intracardiac shunt, a persistent EV [figure 1] and an ascending aorta aneurysm. No pulmonary hypertension or dilatation of the right cavities were found. Chest computed tomography scan did not show proximal pulmonary embolism or pathological lung parenchyma but revealed an ascending aorta aneurysm of 42 mm [figure 2]. Conclusion: We concluded to a PO syndrome in an elderly patient developed on an ascending aortic aneurysm and associated with an EV.