Platypnea-orthodeoxia syndrome treated by percutaneous patent foramen ovale closure: a case report and review of the literature

A high index of suspicion for platypnea-orthodeoxia syndrome is recommended for elderly patients with unexplained hypoxia and shortness of breath. Identification of the underlying mechanisms of platypnea-orthodeoxia syndrome will help determine future therapeutic options. An enlarged aortic root may be the most likely cause of right-to-left shunting in patients with patent-foramen-ovale-induced platypnea-orthodeoxia syndrome. More attention should be paid to aortic root size.