RESUMO
Anomalous left pulmonary artery(pulmonary artery sling) is a congenital anomaly in which the vascular structure arises either from the posterior surface of the right pulmonary artery, or from the main pulmonary artery and courses to the left lung between the posterior surface of the trachea and the anterior surface of the esophagus. It may compress on the tracheobronchial tree causing significant symptoms on the part of the respiratory system such as dyspnea, stridor, or cyanosis. It is a rare condition leading to death in the first months of life, if it is not corrected. We present a case of pulmonary sling who was suffering from recurrent lower respiratory tract diseases, expiratory wheezing, and intermittent dyspnea since birth, thus she was treated for bronchial asthma. We confirmed the diagnosis with computerized tomography, especially with three dimensional reconstruction, which provided information regarding the spatial relationship between the anomalous pulmonary artery branch and the trachea and bronchi.