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

An entity that has received little attention as cause or recurrent respiratory disorder is the narrowing of the left main stem bronchus. When not associated with congenital heart disorders, this condition has been ascribed to primary localized malacia of the bronchial cartilages or to the anterior displacement of the descending aorta in front to the adjacent vertebral bodies. Four girls were evaluated for recurrent/chronic respiratory symptoms. A pulsatile extrinsic compression on the posterior bronchial wall of the left main stem bronchus was detected, pressed between the descending aorta, posteriorly, and the left pulmonary artery, anteriorly. The two arteries were closely linked together by a short-length ligamentum that was resected, allowing the mobilization of the aorta with posterior aortopexy, stabilizing the space created between the pulmonary artery and the descending aorta. The reduced compression on the left main bronchus resulted in the enlargement of its caliber and in a marked improvement of the respiratory symptoms.