Platypnea-orthodeoxia syndrome in an old lady - a clinical challenge

Introduction: Platypnea-orthodeoxia syndrome (POS) is a rare disorder characterized by dyspnoea and oxygen desaturation in the upright position which improves in the supine position. Clinical case: 84 years old woman with hypertension and Parkinson disease. She came to the emergency department complaining of dyspnoea. At admission she was polypneic (35 bpm), sp02 80%, 157/108mmHg, 115bpm, apyretic, normal pulmonary auscultation and without peripheral oedema. Oxygen supplementation was started with lack of response. The patient, which at first was lying in the bed with the headboard at 45 degrees, recovered the peripheral oxygen saturation to 96-97% when the bed was placed at 0 degrees. Diagnostic tests were performed, excluding cardiac myocardial infarction, pulmonary embolism and pneumonia. Transthoracic echocardiogram revealed an aneurys-matic interauricular septum with transoesophageal echocardiogram showing an interauricular communication ostium secundum type with a septa) aneurysm that led to a right to left shunt. The anatomical and clinical features did not allowed percutaneous or surgical closure. After a group discussion we decided for palliative care. Discussion: POS due to a septal aneurysm with right-to-left shunt is a rare and difficult diagnose because it requires a detailed medical examination and exclusion of any other possible diseases. Besides that, it is a very rare presentation in such an old person.