[Asymptomatic pulmonary artery sling: Noninvasive diagnosis].

The anomalous origin of the left pulmonary branch known as pulmonary artery sling (PAS) is a rare form of vascular ring, a congenital heart disease in which the left pulmonary artery originates from the right pulmonary artery and runs posterior to the trachea, encircling it, and goes leftwards between the trachea and oesophagus to reach the left pulmonary hilum. The clinical outcome depends on the associated tracheal lesions and cardiac anomalies. The majority of patients (90%) have respiratory symptoms in the first year of life, due to tracheal stenosis (chronic stridor and wheezing), and with a high mortality rate if there is no surgical intervention. Other major congenital heart diseases are present in up to 50% of patients with this rare vascular ring. We present a case of this rare disease in an asymptomatic 3-year-old girl, without any associated congenital heart disease and the findings in the echocardiography and tomography that made the non-invasive diagnosis possible.