Clinical significance of azygos vein enlargement: radiographic recognition and etiologic analysis.

Azygos vein enlargement can be detected in congestive heart failure, portal hypertension, inferior vena cava thrombosis, right atrial mural thrombosis, a pulmonary embolism, congenital azygos continuation to the inferior vena cava, and the arteriovenous fistula. Radiography, particularly computed tomography (CT), is very useful, not only in recognition of azygos vein enlargement, but also in evaluation of its etiology for the institution of the appropriate treatment of the diseases.