Most common site for opening of TAPVC is -

Ans. is 'a' i.e., Supracardiac TAPVCo 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 tributarieso According to the site or level of connection of the pulmonary veins to the systemic venous system TAPVC has been classified into four typeso Type I (most common: 45%): Anomalous connection at supracardiac level (PV drains into left innominatevein or SVC)o Type II (25%): Anomalous connection at cardiac level (PV joins the coronary sinus or enter right atrium directly)o Type III (25%) : Anomalous connection at infracardiac level (PV drain into portal vein)?o Type IV (5%) : Anomalous connection at multiple levels.o In supracardiac TAPVC the pulmonary veins join to form a single trunk (common pulmonary vein) which than drain through anomalous connection