The problems encountered in the diagnosis and management of pulmonary arteriovenous fistulas are of much current interest. A1-though this lesion was apparently not recognized until 1897 and not successfully treated until 1942,1 it has been reported with increasing frequency in recent years.2-8 The relationship between pulmonary arteriovenous fistulas and hereditary hemorrhagic telangiectasia is well known.9-11 The pulmonary lesions have also been found in association with Laennec's cirrhosis and thyroid carcinoma, although most pulmonary arteriovenous fistulas result from congenital vascular anomalies.12
The basic pathophysiologic lesion is a right-to-left shunt of varying magnitudes. The full-blown clinical syndrome consists of central cyanosis, clubbed fingers, and polycythemia in the presence of a normal heart, often with roentgenologic evidence of a mass lesion in the pulmonary parenchyma. An increase in total blood volume without a concomitant increase in plasma volume has been reported, although exact figures on this point are lacking.