Vascular Ring Division

Definition and intent

A vascular ring is a congenital malformation of the aortic arch system in which the trachea and/or esophagus are encircled by vascular structures, producing airway or feeding symptoms (stridor, recurrent infections, dysphagia, failure to thrive) [1]. Surgical therapy aims at definitive decompression by dividing the constricting element(s) and, when appropriate, remodeling aneurysmal or diverticular components to prevent recurrent compression [2].

Preoperative evaluation

Imaging. Contrast-enhanced CT angiography (CTA) or MR angiography establishes arch sidedness, branching pattern, the position of the ligamentum arteriosum/ductus, and the presence of a Kommerell diverticulum; multiplanar and 3-D reconstructions clarify relationships to the trachea and esophagus [1,3]. When symptoms are dominated by airway disease, dynamic airway CT or bronchoscopy characterizes malacia and associated lesions [2,3].

Physiology and airway. Document baseline swallowing/aspiration risk, vocal cord mobility when feasible, and the degree of airway compromise. A nasogastric/orogastric tube placed at induction is a reliable intraoperative esophageal landmark.

Indications. Symptomatic infants and children are offered repair irrespective of age. Selected asymptomatic patients with severe anatomic constriction or a sizable Kommerell diverticulum (particularly when aneurysmal) are considered for early intervention [2,4].

Standard left thoracotomy approach (for left ligamentum arteriosum rings)

1) Approach

Incision and exposure. A left posterolateral thoracotomy through the third intercostal space provides direct access to the distal arch and proximal descending aorta. Retract the lung anteriorly; open the mediastinal pleura longitudinally over the descending aorta [2].

2) Exposure and identification

Key structures. Identify the descending thoracic aorta, left subclavian artery, ligamentum arteriosum (or ductus), and esophagus. Palpate/visualize the esophageal tube to confirm anatomy. Gentle circumferential mobilization of the esophagus creates a safe plane while protecting the vagus and recurrent laryngeal nerves [2].

Safety. Preserve the thoracic duct (posterior and slightly inferior to the arch), avoid cautery near the aortopulmonary window where the left recurrent laryngeal nerve courses, and keep dissection close to the ligamentum and adjacent aortic wall to minimize nerve injury [1,2].

3) Division and decompression

Definitive step. Double-ligate and divide the ligamentum arteriosum, thereby releasing the fibrous “strap” that completes the ring. Lyse residual peri-esophageal bands and open the mediastinal pleura widely to prevent re-tethering. Confirm that the esophagus is freely mobile and no longer indented by vascular structures (bronchoscopic or esophagoscopic confirmation is ideal when available) [2].

Anatomic variants and tailored maneuvers

• Right aortic arch with aberrant left subclavian artery (ALSA) and left ligamentum (most common). Division of the left ligamentum is essential. If a Kommerell diverticulum produces posterior compression, manage with diverticulum resection and aortoplasty when large/aneurysmal, or posterior plication in select cases; refractory compression from a very posterior ALSA origin may require left subclavian reimplantation to the carotid [4,5].
• Double aortic arch. Divide the smaller (usually left) arch between the carotid and subclavian origins; excise residual fibrous tissue. Ensure the dominant arch is hemodynamically intact and that the trachea is fully released both anteriorly and posteriorly [2,6].
• Left arch with aberrant right subclavian artery (ARSA) and right ligamentum. A right thoracotomy may be more ergonomic. Principles mirror those above; consider ARSA reimplantation if posterior compression persists [4,5].
• Pulmonary artery sling (left PA from right PA passing between trachea and esophagus). Not a true ring but a key differential. Management is LPA reimplantation anterior to the trachea, with slide tracheoplasty when complete tracheal rings are present [7].

Technical pearls

• Place silastic vessel loops around the ligamentum and adjacent great vessels to improve control and definition [2].
• Advance a fine right-angle clamp hugging the ligamentum to avoid the left recurrent laryngeal nerve [1,2].
• After division, widely mobilize the esophagus and release all fibrous bands—an incomplete release is the most common cause of persistent symptoms [2].
• If the pleural space is widely opened or a diverticulum is resected, leave a pleural drain; otherwise a small apical drain often suffices [2].

Alternative approaches

Video-assisted thoracoscopic division has been reported with high success and shorter convalescence in experienced centers, with conversion reserved for dense adhesions or bleeding [8]. Selection depends on patient size, anatomy (e.g., large Kommerell diverticulum), and institutional expertise [8].

Postoperative management

Airway. Transient stridor is common due to pre-existing tracheobronchomalacia; humidified oxygen, gentle suctioning, and time usually suffice. Severe collapse may merit noninvasive support or tracheoplasty if not addressed at the index operation [1,7].

Feeding. Advance as tolerated after confirming no esophageal injury; thickened feeds can help dysphagia in infants [1,2].

Complications to watch. Chylothorax from thoracic-duct injury, recurrent laryngeal nerve palsy (hoarseness/aspiration), tracheal or esophageal injury, bleeding, and residual compression from an untreated diverticulum or posterior subclavian course [1,2,4].

Outcomes and follow-up

Across large series, symptom relief is achieved in the vast majority of children (typically >85–90%), with persistent respiratory symptoms most often reflecting pre-existing tracheobronchomalacia that improves over months [2,6]. Reintervention is uncommon and usually relates to residual or recurrent compression (e.g., unaddressed diverticulum or persistent posterior subclavian course) [4,6]. Follow-up focuses on breathing and feeding trajectories, with targeted imaging if symptoms persist or if a diverticulum was resected/repaired [2,4].

References

[1] Humphrey C, Duncan K, Fletcher S. Vascular rings: current concepts in diagnosis and management. Int J Pediatr Otorhinolaryngol. 2006;70(3):347-354.

[2] Backer CL, Mavroudis C, Rigsby CK, Holinger LD. Trends in vascular ring surgery: a contemporary 10-year experience. Eur J Cardiothorac Surg. 2005;27(4):586-592.

[3] Lee EY, Boiselle PM, Cleveland RH. Multidetector CT evaluation of congenital lung anomalies in pediatric patients: emphasis on 3D CT imaging. Radiographics. 2008;28(6):1727-1738.

[4] Cinà CS, Althani H, Pasenau J, Abouzahr L. Kommerell’s diverticulum and right-sided aortic arch: a cohort study and review of the literature. Ann Thorac Surg. 2004;77(1):210-214.

[5] Idrees J, Keshavamurthy S, Subramanian S, et al. Hybrid repair of Kommerell diverticulum. J Thorac Cardiovasc Surg. 2014;147(3):973-976.

[6] Ruzmetov M, Vijay P, Rodefeld MD, Turrentine MW, Brown JW. Follow-up of surgical correction of aortic arch anomalies causing tracheoesophageal compression (vascular rings). Ann Thorac Surg. 2009;88(6):1951-1956.

[7] Tsang V, Murday A, Gillbe C, Goldstraw P. Slide tracheoplasty for congenital funnel-shaped (long-segment) tracheal stenosis. Ann Thorac Surg. 1994;58(3):832-836.

[8] Koontz CS, Smith LA, Burford JM, Hebra A. Thoracoscopic division of vascular rings in children. J Pediatr Surg. 2005;40(11):1828-1832.