Background: A partial anomalous pulmonary venous connection is a rare congenital defect in which blood from the pulmonary vein is returned to the right atrium. Asymptomatic patients with a partial anomalous pulmonary venous connection with a small left-to-right shunt do not require surgical treatment. If such patients require a major lung resection, the surgical procedure could precipitate fetal right heart failure if the anomalous venous connection remains uncorrected.
Case presentation: A 59-year-old man was found to have an abnormal shadow on chest roentgenogram. Chest computed tomography imaging showed a mass in the right upper lobe. At the same time, we incidentally found an anomalous vessel. We diagnosed the abnormality as a partial anomalous pulmonary venous connection. Because the mass may have been lung cancer, a right upper lobectomy was performed using video-assisted thoracoscopic surgery. The right upper lobe vein drained into the superior vena cava. The anomaly was not corrected and the surgery was successful. His postoperative course was uneventful without cardiac failure.
Conclusions: Before performing a major lung resection, surgeons should be aware of this rare anomaly and carefully interpret clinical images of all pulmonary veins.
Keywords: Case report; Lung cancer; Partial anomalous pulmonary venous connection; Video-assisted thoracoscopic surgery.