Unmasking an Anomalous Vein: Surgical Repair of Left Upper Pulmonary Vein Drainage into the Innominate Vein.

Partial anomalous pulmonary venous return (PAPVR) is a rare congenital anomaly characterized by one or more pulmonary veins draining into the systemic venous system. We present the case of a 51-year-old woman with PAPVR involving the left upper pulmonary vein (LUPV) draining into the left innominate vein via a vertical vein, diagnosed after investigation of progressive dyspnea and lower limb edema. The diagnosis was confirmed through contrast-enhanced CT and echocardiography. The patient underwent surgical correction of the anomalous return along with tricuspid valve repair. Postoperative recovery was uneventful. This case highlights the importance of recognizing PAPVR in adult patients presenting with unexplained right heart dilation or symptoms of right heart overload.