Diagnosis and Management of Left Main Stem Bronchus Compression

Abstract

There are four major variants of congenital vascular tracheal compression: innominate artery, aberrant subclavian, aorta or aortic arch anomaly, and pulmonary artery sling. These forms of vascular compression typically involve the trachea and/or the right main stem bronchus. We present eight cases of congenital vascular compression involving the left main stem bronchus. These cases represent a poorly understood variant of vascular tracheal compression. This variant represents approximately 10% of our pediatric tracheobronchial compression or stenosis patients. The finding, both noted endoscopically and now illustrated by magnetic resonance imaging, is caused by compression of the left main stem bronchus between the descending aorta and a portion of the pulmonary artery. Frequently, the descending aorta is in an abnormal anterior position with relation to the thoracic spine. Recognition of this entity is important in our experience and has influenced clinical management. In four of eight children, it required a surgical procedure directed toward the relief of the left main stem compression.

Series of laryngomalacia, tracheomalacia, and bronchomalacia disorders and their associations with other conditions in children

“…Defining this ''inverted teardrop'' appearance is a controversial diagnostic issue. 16,17 While this appearance is common at entry into the left main stem, closer inspection often reveals the appearance to be due to the curvature of the left main stem without any apparent real reduction in cross-sectional area. While such cases were not included or diagnosed as malacia in this series, the lack of objective measurements necessary to define the normal and observed changes remains a difficulty in assessing minor changes of the left mainstem bronchus.…”

Pediatric bronchoscopy

“…Foreign bodies, tracheobronchial or vascular malformations, 46 and intrathoracic airway malacia or stenosis 47 are occasionally found. Compression of the left main stem bronchus was the focus of a recent article, 49 and the most frequent cause seems to be an abnormal prespinal position of the descending aorta, which compresses the bronchus against the left pulmonary artery. 48 Other diagnostic options such as a lateral chest X-ray, computed tomography (CT) scan, and magnetic resonance imaging (MRI), will often not give suf®cient information to obviate endoscopy.…”

Short-length ligamentum arteriosum as a cause of congenital narrowing of the left main stem bronchus

“…However, previous reports showed that this condition may be also related to compression by congenital anomalies of the thoracic aorta and/or of the pulmonary arteries . In these reports, the etiologic factors found to be most frequently associated with this entity were the anterior displacement of the descending aorta in front to the adjacent vertebral bodies and dilatation of the pulmonary arteries . In children with more severe symptoms, surgical treatment varied according to the complexity of the anatomic anomalies and, when indicated, included posterior aortopexy .…”

“…This condition is usually not included in the list of airway anomalies caused by vascular compression because, when not associated with cardiovascular anomalies, it generally attributed to primary localized chondromalacia . However, previous reports showed that this condition may be also related to compression by congenital anomalies of the thoracic aorta and/or of the pulmonary arteries . In these reports, the etiologic factors found to be most frequently associated with this entity were the anterior displacement of the descending aorta in front to the adjacent vertebral bodies and dilatation of the pulmonary arteries .…”

“…In these reports, the etiologic factors found to be most frequently associated with this entity were the anterior displacement of the descending aorta in front to the adjacent vertebral bodies and dilatation of the pulmonary arteries . In children with more severe symptoms, surgical treatment varied according to the complexity of the anatomic anomalies and, when indicated, included posterior aortopexy . We present the cases of four girls in which the extrinsic compression of the left main stem bronchus was due to a short‐length ligamentum arteriosum, tightly linking the descending aorta to the origin of the left pulmonary artery.…”