Supracardiac Total Anomalous Pulmonary Venous Return (TAPVR)

Echocardiography demonstrates supracardiac total anomalous pulmonary venous connection/return (TAPVC/R) with obstruction at the level of the left-sided vertical vein, with a peak gradient of 13 mmHg and a mean gradient of 7.5 mmHg across the obstruction. The right upper and lower pulmonary veins form a common confluence draining into the base of the vertical vein, while the left lower pulmonary vein drains into a smaller confluence that subsequently connects to the vertical vein. The left upper pulmonary vein drains separately into the base of the vertical vein. There is associated dilation of the superior vena cava (SVC) and innominate vein (due to the drainage of the confluence towards these systemic veins). A moderate fenestrated secundum atrial septal defect within the fossa ovalis is present, consisting of multiple defects with right-to-left shunting (obligatory right to left shunting). A large patent ductus arteriosus (PDA) demonstrates bidirectional shunting, with right-to-left flow in systole (peak gradient 5 mmHg) and left-to-right flow in diastole (peak gradient 1.7 mmHg).