[A case of successful resection of pulmonary arteriovenous fistula with a high shunt ratio].

We report on a 25-year-old cyanotic man who was diagnosed as having a pulmonary arteriovenous fistula. His chief complaint had been shortness of breath since childhood. Polycythemia (Hb 21.4 g/dl) was detected during a health checkup at his company. A chest X-ray showed an abnormal mass in the left lung. Blood gas analysis showed severe hypoxia with PaO2 of 38.6 mmHg at room air. Angio-CT showed a large aneurysmal lesion at S6 of the left lung with a large feeding artery and vein. Oxygen saturation was 75.2% in the radial artery and 62.5% in the right atrium. The right-to-left shunt ratio was therefore calculated as 62%. The aneurysmal lesion was resected by segmentectomy of the left S6 following division of A6 and V6. After a successful operation, the patient no longer had shortness of breath or cyanosis and blood gas analysis showed PaO2 as 84.3 mmHg at room air. Pulmonary angiography showed no residual shunt lesion.