Pulmonary Artery Sling

Excerpt

A broad category of congenital vascular anomalies from the aortic arch is referred to as a "vascular ring." There are many varieties of vascular rings. Pulmonary artery sling (PAS) is a rare type of vascular ring. Specifically, PAS is an embryologic vascular anomaly subclassification where the origin of the left pulmonary artery arises from the right pulmonary artery, instead of the main pulmonary artery. This compresses the distal trachea and right mainstem bronchus between the trachea and esophagus towards supplying the left lung, known as a "vascular sling." PAS is not considered a "true complete" vascular ring, but symptoms can be similar.

Symptoms are non-specific and are due to the abnormal anatomic course of the left pulmonary artery coursing between the esophagus and trachea. Once PAS is diagnosed, patients will be recommended to undergo surgical repair. Although staged repair can be considered for these complex patients with associated cardiac anomalies and congenital tracheal stenosis, recent reports suggest that patients can have good outcomes with a simultaneous repair. Infants who require tracheoplasty for long-segment tracheal stenosis or complex cardiac anomalies remain challenging despite improved outcomes for PAS repair with left pulmonary artery reimplantation.

Glaevecke and Doehle first described PAS in 1897. Dr. Willis Potts performed the first successful surgical repair of PAS on a 5-month old through a right thoracotomy approach in 1953. The left pulmonary artery was divided and re-anastomosed anterior to the trachea. However, follow-up imaging demonstrated technical difficulty with limited blood flow to the lung on the left side. Current results are more favorable with improvement in surgical technique and long-term patency of the re-implanted left pulmonary artery.