Pulmonary arteriovenous malformations: aspects of surgical therapy

Pulmonary arteriovenous malformations (PAVM) may occur primarily or in association with hereditary hemorrhagic telangiectasia (HHT, Rendu-Osler-Weber syndrome). Solitary or multiple fistulas may lead to clinical symptoms such as dyspnoe on exertion, central cyanosis, polycythemia, cerebral embolism, or brain abscess formation. Major neurological events may be first symptoms of PAVM. Between 1991 and 1995, 6 patients (age 25-69 years) underwent surgical treatment (2 segmental, 1 atypical, 3 anatomical resections) due to PAVM. The highest right-to left shunt fraction was 60% in a patient with a large posttraumatic fistula following war injury 50 years ago. Average shunt fraction was significantly reduced from 24 to 3% (p < 0.01), with no recurrance during follow-up. Aims of surgical resection in patients with PAVM are to reduce shunt fraction and to prevent neurological events following repeated cerebral embolism. Atypical or segmental resection is the operative method of choice; however, this is only recommended, if all contributing arteries are identified and selectively ligated. In case of central location of large fistulas, lobectomy may be necessary. Percutaneous selective embolization is an alternative treatment for patients with high operative risk or multiple fistulas. Its role for routine therapy remains to be determined by clinical studies.