Pulmonary Venous Atresia with Abnormal Drainage in a Neonate: A Case of Missing Vein

Pulmonary Venous Atresia (PVA) is a rare congenital cardiovascular anomaly in which one or more pulmonary veins fail to establish a normal connection with the left atrium, resulting in obstruction of pulmonary venous return and progressive pulmonary venous hypertension. When associated with Partial Anomalous Pulmonary Venous Connection (PAPVC), pulmonary venous drainage is redirected into the systemic venous circulation, leading to abnormal haemodynamics and right-sided cardiac volume overload. Early recognition is essential because delayed diagnosis may result in severe cardiopulmonary complications. This case report describes a 30-day-old male neonate who presented with persistent respiratory distress, feeding difficulty, tachypnoea, and mild central cyanosis. Chest radiography demonstrated mild cardiomegaly with prominent pulmonary vascular markings. Transthoracic echocardiography revealed dilatation of the right atrium and right ventricle with a relatively small left atrium; however, pulmonary venous connections were not clearly visualised. Multidetector Computed Tomography (MDCT) angiography was therefore performed for detailed anatomical evaluation. Imaging demonstrated absence of the right pulmonary veins and the left lower pulmonary vein, consistent with PVA. The remaining left upper pulmonary vein drained anomalously into the left innominate vein through a vertical vein, representing PAPVC. The infant underwent surgical rerouting of the anomalous vertical vein to the left atrium with closure of the Atrial Septal Defect (ASD), successfully restoring physiological pulmonary venous drainage. Postoperatively, oxygen saturation improved and respiratory symptoms resolved. This case highlights the importance of MDCT angiography in accurately delineating complex pulmonary venous anomalies and guiding timely surgical management.