[A case of unusual shaped pulmonary arteriovenous fistula].

Autopsy findings of pulmonary arteriovenous fistula (PAVF) was initially described by Churton in 1897. Since then, several hundreds of cases have been reported in Europe and the United States. In Japan, there has recently been an increase in case reports of PAVF. PAVF seems to be no longer a rare disorder in Japan. Several morphological classifications of PAVF have been reported. One of these classifies PAVF into 1) solitary types 2) multiple types and 3) diffuse telangiectasia. Another, for example, classifies the disorder into the following 3 types: 1) multiple telangiectasia 2) pulmonary arterial aneurysm and 3) pulmonary artery-left atrial communications. Many other classifications have been proposed. In the solitary type (PA aneurysmal type), fistulas are located at the relatively large, central vessels. Here we report a case of PAVF which presented not as a solitary aneurysm but rather as a distended and tortuous anomalous vessel.