A 44 years old female was admitted with previous history of several cerebral vascular accident (CVA). A transthoracic echocardiogram showed a patent foramen ovale (PFO) that was closed, under extracorporeal circulation. The patient remained free of symptoms for ten years. In the year 2003 she was admitted to our hospital with paresthesias of the left arm. The clinical evaluation led to the diagnosis of arteriovenous fistula (AVF) of the lung. In November 2003, the patient underwent right inferior lobectomy. This is a rare association of PFO with AVF fistula of the lung with a delayed diagnosis. The differential diagnosis, the surgical treatment and the most frequent complications of this pathology are reported and discussed.