Abnormalities of Pulmonary Venous Return

Abnormalities of pulmonary venous return in adults result from anomalous drainage of one or more pulmonary veins into a systemic vein, resulting in a left-to-right shunt. Partial anomalous pulmonary venous return (PAPVR) is most commonly encountered in adults in the upper lobes. PAPVR in the right upper lobe is commonly associated with a sinus venous atrial septal defect, whereas in the right lower lobe it is commonly encountered in association with other anomalies in Scimitar syndrome. Left upper lobe PAPVR is usually isolated. In some instances, patients can develop pulmonary over-circulation and hypertension, necessitating intervention. This chapter emphasizes CT and MR features key to recognizing and diagnosing these anomalies.