Platypnea-orthodeoxia: report of two cases and review of the literature.

We describe two unusual cases of platypnea. The first patient had chronic obstructive pulmonary disease, but platypnea did not respond to chronic obstructive pulmonary disease therapy. He was found to have multiple pulmonary emboli, and symptoms rapidly improved on anticoagulation therapy. The second patient had Parkinson disease and developed severe platypnea, an association that has not been previously described. She had significant postural hypotension and responded to therapy with fludrocortisone.