Most common type of TAPVC -

Ans. is 'a' Supracardiac * Total anomalous pulmonary venous connection (TAPVC) is characterized by abnormal drainage of pulmonary veins into the right heart either by direct connection into the right atrium or into its tributaries.* According to the site or level of connection of the pulmonary veins to the systemic venous system TAPVC has been classified into four types# Type I (most common: 45%): Anomalous connection at supracardiac level (PV drains into left innominate vein or SVC).# Type II (25%): Anomalous connection at cardiac level (PV joins the coronary sinus or enter right atrium directly).# Type III (25%): Anomalous connection at infracardiac level (PV drain into portal vein).# Type IV (5%): Anomalous connection at multiple levels.* In supracardiac TAPVC the pulmonary veins join to form a single trunk (common pulmonary vein) which than drain through anomalous connection.