Fistulous connection between the left pulmonary artery and the innominate vein

A 66-yr-old woman was admitted to our clinic with signs and symptoms suggesting either pulmonary embolism or pneumonia. Subsequently she was diagnosed as having pneumonia, but since pulmonary artery pressure was high on echocardiography, pulmonary angiography was performed to exclude the possibility of pulmonary embolism. No findings suggestive of pulmonary embolism were evident on pulmonary angiogram, but there was a fistulous connection between the left pulmonary artery and the innominate vein. To our knowledge, this report represents the first case of a fistula between the pulmonary artery and a systemic vein.