Total Anomalous Pulmonary Venous Drainage with Malaligned Atrial Septum: A Case Series and Descriptive Study

Abstract

Abstract Total anomalous pulmonary venous drainage (TAPVD) is a complex congenital heart anomaly characterized by abnormal venous return from the pulmonary veins. The classification of TAPVD has been a matter of debate, particularly when pulmonary veins open into the anatomically left atrium but functionally into the right atrium due to a malaligned interatrial septum. This case series aimed to assess clinical significance of malalignment of interatrial septum and to differentiate between TAPVD and total anomalous pulmonary venous connection (TAPVC) by echocardiography before sending the patient for surgery. This retrospective case series involved seven patients diagnosed as TAPVD between 2011 and 2023. The age of the patients ranged from 1 month to 3 years, mostly presenting within the first few months of life. One case was diagnosed during fetal echocardiography. The commonest complaints were failure to thrive, fast breathing and recurrent chest infection. All cases were diagnosed by echocardiography and confirmed during surgery. 5 patients had situs solitus, 1 had situs inversus and one had left isomerism. In all cases, surgical repair was done which included excision of malaligned interatrial septum and closing the interatrial defect with dacron patch, thus directing the flow of the pulmonary vein to the left atrium. In summary, TAPVD with malaligned interatrial septum and TAPVC are two completely different entities and must be differentiated before sending the patient for surgical repair. The normal anatomical connection of pulmonary veins to left atrium is preserved in TAPVD.