Pulmonary arteriovenous fistula: Angiocardiographic observations in nine cases

Abstract

Pulmonary arteriovenous fistulas are hereditary hemangiomatous malformations of the pulmonary vascular bed. Almost 40 per cent of the reported cases also have hemangiomas elsewhere in the body, indicating that a close relationship to familial hemorrhagic telangiectasis (Rendu-Osier-Weber's disease) exists. When pulmonary arteriovenous fistulas are large and do not have systemic arterial connections, dyspnea, cyanosis, clubbing of the digits and polycythemia result from unsaturation of the blood. Hemoptysis may occur when there is rupture of the paper-thin pulmonary vascular anomaly. There is also a high incidence of cerebral symptoms due either to cerebral thrombosis, secondary to the polycythemia, or to infection, especially brain abscess. The heart remains normal in size because pulmonary arteriovenous fistulas do not cause increased pulmonary vascular resistance. In our series of nine cases the classical syndrome of cyanosis, clubbing of digits, polycythemia and a vascular murmur heard over the pulmonary fistula was present in one case only. One patient with dyspnea, fatigue and familial telangiectasis had bilateral pulmonary arteriovenous fistulas; chronic anemia prevented intense cyanosis and polycythemia. In three instances the patients were asymptomatic; in two the pulmonary arteriovenous fistula was an incidental finding; in the remaining two, acute cerebral conditions (brain abscess and meningoencephalitis) were the presenting symptoms. Vascular bruits were heard in eight patients. All patients had abnormal chest roentgenograms. The diagnosis of pulmonary arteriovenous fistula can often be made by conventional roentgenography, particularly if the index of suspicion is high. Pulmonary densities with hilar vascular connections localized in lobes or segments of the lung, or increased hilar vascularities, should arouse suspicion of an arteriovenous fistula. Change in size of the lesions after respiratory maneuvers (Valsalva, Müller) and delineation of the afferent arterial and efferent venous connections by body section radiography may be confirmatory. Angiocardiography, however, establishes the diagnosis and is recommended for preoperative evaluation. The treatment of pulmonary arteriovenous fistulas is surgical excision, with preservation of as much lung tissue as possible in order to preserve pulmonary function, especially if multiple lesions are present. Surgery is usually curative. It is recommended by some even in the asymptomatic case since the risk of brain abscess, fatal hemoptysis or development of cerebral thrombosis when polycythemia occurs is far greater than the morbidity and mortality of lobectomy or segmental resection.