Clinical and imaging features of pulmonary artery sling in infants without significant hemodynamic changes

Background Pulmonary artery sling （PAS） is a rare congenital heart anomaly and may cause unexplained respiratory symptoms in infants. Since the non-specific respiratory symptoms of PAS may lead to misdiagnosis, the aim of this study was to clarify the clinical and imaging features of this disease for timely diagnosis and treatment. Methods Clinical histories, physical examinations and imaging studies were retrospectively evaluated in nine infants with PAS. Chest X-ray, echocardiography and contrast-enhanced computed tomography （CT） with 3-dimensional reconstructions were performed in all patients and three of them received surgical treatment. Results Nine cases included six males and three females with a mean age of （4.3_＋_2.8） months ranging from 2 to 11 months old. All patients had respiratory symptoms including recurrent cough, stridor and wheezing. The onset of symptoms was within 3 months in all cases and three children had symptoms only a few days after birth. The chest X-ray showed pneumonia in all cases. Contrast-enhanced CT showed the tracheal compression at different lengths in every case. The echocardiograph findings of PAS were anomalous origins of the left pulmonary artery from the posterior aspect of the right pulmonary artery. Of the 9 cases, 8 cases were diagnosed correctly by echocardiography. Of the complicated abnormalities, there were one with secundum atrial septal defect, one with patent foramen ovale and three with persistent left superior vena cava. None of them were complicated with significant blood dynamic changes. Conclusions Infants with recurrent respiratory symptoms such as chronic cough, stridor and wheezing, should be examined for the possible presence of congenital pulmonary artery sling. As a noninvasive technique, echocardiography is very helpful and should be the first-choice modality for the diagnosis of pulmonary artery sling. Contrast-enhanced CT, clearly demonstrating the anatomy of pulmonary artery sling and the position and extent of trachea compression, is necessary for the final diaqnosis and pre-operation evaluation.

Multi-detector computed tomography evaluation of tracheobronchial anomaly in pediatric patients with left pulmonary artery sling

The left pulmonary artery sling （LPAS） is a rare vascular anomaly causing respiratory distress in which theleft pulmonary artery arises from the posterior aspect of the right pulmonary artery, courses posteriorly to the right of the bronchus and passes between the trachea and oesophagus to reach the hilum of the left lung. The LPAS is frequently associated with tracheobronchial tree anomalies and congenital cardiac defects. Proper assessment of the tracheobronchial and cardiovascular anomaly is essential in LPAS for planning management of the patient. Currently,