Four‐Dimensional Computed Tomography Differentiates Congenital Right Pulmonary Vein Atresia From Suspected Arteriovenous Malformation: A Case Report

Congenital pulmonary vein atresia (PVA) is a rare condition often associated with vascular anomalies and complex pulmonary hemodynamics. A 54-year-old woman was referred for evaluation of a nodular shadow in the right upper lobe, initially suspected to represent a pulmonary arteriovenous malformation (PAVM). Four-dimensional enhanced computed tomography (4D-CT) revealed no abnormal vessels, suggesting a PAVM in the pulmonary arterial phase. However, in the venous phase, the pulmonary vein of the right upper lobe was occluded at the trunk, with reflux via a pulmonary vein varix and an abnormal vein draining into the pulmonary vein of the right middle lobe. Due to the risk of pulmonary hypertension, thromboembolism, or varix rupture, the patient underwent right upper lobectomy. 4D-CT effectively delineates the vascular morphology by separating the pulmonary arterial and venous phases. Congenital PVA may involve pulmonary vein varices and abnormal vascular formation; 4D-CT may be valuable for diagnosis and treatment planning.