Partial anomalous pulmonary venous return is a congenital anomaly in which one or more, but not all, of the pulmonary veins are connected to a systemic vein, the coronary sinus, or the right atrium directly. These aberrant veins usually connect to the closest systemic vein. When anomalous drainage occurs in the left upper lobe, it is often through a so-called vertical vein, which drains into the left innominate vein. The great majority of these anomalies presents no clinical symptoms and are discovered on routine chest radiographs or computed tomographic (Cl') scans of the lung done for other reasons. In this report, a 61-year-old woman was initially diagnosed to have an atrial defect, found out to have a partial anomalous pulmonary venous return on further work-up. Repair was done under extracorporeal circulation and used a sauvage patch to redirect the pulmonary venous flow to the left atrium. Symptoms resolved after the operation with hemodynamics improved on follow-up examinations.