OBJECTIVE The aim of this study was to assess the effectiveness of percutaneous treatment of PAVFs through the results of long-term follow-up. METHODS Transcatheter embolization of PAVFs using spring coils was performed in seven patients (six women and one man) with nine PAVFs, between 1989 and 1995, who were followed up at least one year. The size of the nine PAVFs ranged from 4 mm to 70 mm in diameter (mean 26 mm). Two fistulas were huge, 70 x 45 mm and 60 x 65 mm in diameter. Embolization was performed twice in three patients and once in four patients. In the two patients with huge PAVFs, after anchoring metallic "spiders" into the feeding artery, the largest coils were positioned and entangled with the "spider" followed by the placement of smaller coils to fill in the center of the feeding artery. RESULTS No severe complications were seen in the short-term follow-up. Arterial oxygen pressure improved in all patients with low oxygen pressure. Five patients with seven fistulas, six of which disappeared on chest X-ray film, are still alive after follow-up ranging from one year and 10 months to seven years and nine months. The two patients with huge fistulas died more than one year after treatment, one of hemoptysis of the contralateral lung and the other of pulmonary fibrosis. CONCLUSIONS Complete embolization of a medium-sized feeding artery can cure this anomaly.