title: Pulmonary arteriovenous fistula showing a fall in shunt fraction during exercise.
abstract: A 23-year-old man with pulmonary arteriovenous fistulas of the right middle lobe is described. During the incremental exercise test, the shunt fraction dropped from 19 percent to 12 percent as the cardiac output increased. We discuss the mechanism of this fall in shunt fraction in this patient during exercise.
mesh_terms: D000328:Adult; D001165:Arteriovenous Malformations / Q000503:physiopathology*; D002302:Cardiac Output; D005080:Exercise Test; D006801:Humans; D008297:Male; D010100:Oxygen / Q000097:blood; D011651:Pulmonary Artery; D011667:Pulmonary Veins
chemical_list: D010100:Oxygen