IS case 472: Azygos vein enlargement secondary to pulmonary arterial hypertension and right-sided heart failure
Imaging Sciences URMC 2010
Publication Date: 2010-08-30
Azygos vein enlargement is defined as an azygos vein measuring greater than 7 mm diameter on an upright chest radiograph. It can be secondary to a number of different disease states involving two primary categories: a need for collateral circulation and engorgement due to right atrial hypertension. The azygos vein becomes a collateral vessel in the following states: portal hypertension, SVC obstruction/compression below the azygos vein, IVC obstruction/compression, interrupted IVC with azygos continuation, and partial anomalous venous return. Azygos enlargement is seen with right atrial hypertension in right-sided heart failure, constrictive pericarditis, and large pericardial effusion.
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