Pulmonary arteriovenous fistula discovered after percutaneous patent foramen ovale closure in a 27-year-old woman.

We report the case of a 27-year-old woman with history of a transient ischemic attack who was diagnosed with a large patent foramen ovale (PFO). After percutaneous PFO closure, it was discovered that the patient had a pulmonary arteriovenous malformation (PAVM) and a diagnosis of hereditary hemorrhagic telangiectasia was made. The PAVM was later coil embolized. This case illustrates the importance of evaluating PFO closure patients for other causes of right-to-left shunting.