Anomalous pulmonary venous connection

Anomalous pulmonary venous connection (or anomalous pulmonary venous drainage or anomalous pulmonary venous return) is a congenital heart defect of the pulmonary veins. It can involve either all four pulmonary veins being incorrectly positioned (total anomalous pulmonary venous connection) or only some veins being incorrectly positioned (partial anomalous pulmonary venous connection).