ulmonary arteriovenous fistulas are abnormal connections between a pulmonary artery and vein. A close relationship between a pulmonary arteriovenous fistula and hereditary hemorrhagic telangiectasia has often been noted and the occurrence of pulmonary arteriovenous fistulas without a family history of telangiectasia is rare. The diffuse type of arteriovenous fistula is difficult to recognize, because it exhibits no abnormal findings on chest radiography or pulmonary arteriography. We report here an adult case of diffuse pulmonary arteriovenous fistulas.
Case ReportA 30-year-old Japanese woman was admitted to hospital for dyspnea. She had suffered from cyanosis during infancy, and underwent corrective surgery for a large atrial septal defect (ASD) and partial anomalous pulmonary venous drainage when she was 3 years old. However, her cyanosis continued postoperatively.Her height was 156 cm, weight 47 kg, blood pressure 100/60 mmHg in both arms with a pulse of 80 /min and regular respiratory rate of 25 /min. She exhibited cyanosis and digital clubbing, but no telangiectasia. The lungs were clear to auscultation. The second heart sound was split widely and fixed, but no cardiac murmurs was audible. The electrocardiogram and chest radiograph were normal. Thoracic computed tomography showed dilated azygos and hemiazygos veins. Neurological examination was normal. Arterial blood gas analysis revealed pH 7.454, PO2 47.0, PCO2 33.1 mmHg and SaO2 84%. Transthoracic echocardiography did not reveal atrial septal defect or abnormal Japanese Circulation Journal Vol.63, June 1999 shunt flow. Contrast echocardiograms following the injection of saline agitated with small amount of air revealed a cloud of tiny bubbles appearing first in the right ventricle. After 3 s, these bubbles appeared in the left ventricle, entering through the mitral valve funnel. Angiography revealed doubled inferior vena cavas (IVC); the left IVC and left external iliac vein were connected with the hemiazygos vein, and the right IVC with the left atrium through a small orifice (Fig 1). Most of the blood from the IVCs flowed into the superior vena cava (SVC) via the distended azygos and hemiazygos veins (Fig 2). Pulmonary arteriography revealed no abnormal structures. The mean pulmonary arterial pressure was 10 mmHg. Oxygen saturations in the left upper, right upper and lower pulmonary veins were 85.6, 78.8 and 83.0%, respectively. Perfusion lung scintigraphy, using 99m Tc-macroagglutinated albumin (MAA), showed multiple segmental perfusion defects in the lung fields and accumulation in the kidneys, although ventilation lung scans revealed no defects (Fig 3).
Microscopic pulmonary arteriovenous fistulas appearedJpn Circ J 1999; 63: 499 -501 (Received November 11, 1998; revised manuscript received March 2, 1999; accepted March 18, 1999) A 30-year-old Japanese woman was admitted to hospital for dyspnea. She had a history of corrective surgery for a large atrial septal defect and partial anomalous pulmonary venous drainage, which had produced cyanosis in...