Supracardiac Total Anomalous Pulmonary Venous Return
Overview and natural history
Total anomalous pulmonary venous return, also known as total anomalous pulmonary venous connection is a form of cyanotic heart disease where all four pulmonary veins have anomalous connections to the systemic venous circulation. There are four main types: supracardiac, intracardiac, infracardiac or mixed venous drainage.
In supracardiac total anomalous pulmonary venous return, the pulmonary veins typically drain to a left sided vertical vein which ultimately drains into the innominate vein or superior vena cava. The vertical vein usually travels anterior to the left pulmonary artery and mainstem bronchus, however, in some cases it may become obstructed along its course, most commonly if it travels between the left pulmonary artery and mainstrem bronchus. A PFO/ASD must be present in this lesion to allow the anomalous venous drainage to reach the systemic circulation.
Early atresia of the common pulmonary vein while pulmonary-systemic venous connections are still present
Depends on whether obstructed or unobstructed. If pulmonary veins are unobstructed behaves like a large ASD (left to right shunt). With obstruction, patient may manifest tachypnea and feeding difficulties in the first few days or weeks of life. Severe obstruction causes decreased pulmonary blood flow with worsening cyanosis