Partial anomalous pulmonary venous return: case report and review of the literature.

Isolated partial anomalous pulmonary venous return (APVR) is an uncommon finding. A patient with isolated APVR had pulmonary hypertension without demonstrable left-to-right shunting prior to anticoagulant treatment of pulmonary emboli. After anticoagulant therapy, with a fall in pulmonary pressures and resistance to near-normal levels, left-to-right shunting was then detected by oximetry and angiography.