Adult presentation of right lung agenesis and left pulmonary artery sling

The combination of right lung agenesis and left pulmonary artery (LPA) sling is a rare entity that has been described only in the pediatric population. Cross-sectional imaging modalities such as magnetic resonance imaging (MRI) and computed tomography (CT) have an advantage over echocardiography and pulmonary angiography in demonstrating the anomalous left pulmonary artery, particularly in the presence of coexisting lung agenesis, as exemplified in this case. We report the first case of this rare entity in an adult. It is important to be aware that this abnormality, though rare, can present even in adulthood, and therefore close attention should be paid to the course of the pulmonary artery to ensure detection of a sling in association with lung agenesis.