Patient is a 56-year-old male with a past medical history of type 2 diabetes, hypertension, prior MVA with chest trauma, and coronary artery disease with 2 prior stents in the obtuse marginal and right coronary artery who was brought to the ED for severe chest pain. Patient was immediately taken to the cath lab for cardiac intervention. Patient was identified to have 90-95% stenosis of his left circumflex but was unable to be stented due to tortuosity of the vessel and tight lesion. Due to patient’s multivessel coronary artery disease and newly diagnosed diabetes, patient was referred to cardiothoracic surgery for potential bypass surgery. Patient underwent routine pre-operative screening with a STS mortality risk score of 0.5%. Chest CT scan was identified to have left upper lobe pulmonary vein that drains into the left lateral brachiocephalic vein which is consistent with a partial anomalous pulmonary venous return (PAPVR). After identifying these findings, patient underwent right sided cardiac catheterization and cardiac MRI for further pre-operative assessment. Transesophageal echocardiogram was negative for any obvious or large interatrial septal defect. The prevalence of PAPVR is about 0.4-0.7%. Clinically, patient presentation may vary from asymptomatic to complete right heart failure requiring heart transplant. PAPVR more commonly affects the right upper lobe vein and is associated with an atrial septal defect in 80-90% of cases. Left-sided PAPVR is only present in about 10% cases, of which the vast majority go undiagnosed until the development of symptoms or the need for pulmonary mapping in instances of percutaneous ablation for atrial fibrillation or consideration of lobectomy in lung neoplasm. Case was discussed with congenital heart surgery team. After much discussion, it was determined that conservative nonoperative management of the anomaly was appropriate and proceed with coronary bypass surgery only. Here we examined a case of an extremely rare presentation of PAPVR originating in the left upper lobe with no evidence of ASD. This anomaly complicated the patient’s course on whether his bypass graft would entail surgical repair of the PAPVR. Recent advancements in sophisticated diagnostic imaging and greater knowledge of this anatomical variation have increased the frequency with which this condition is diagnosed. With the suspected increase in incidence, it may be time for the creation of formal guidelines on a global scale instead of relying on recommendations on consensus of symptomatology.