see also: Pediatric Airway; Pediatric Airway - Cross sectional area; Pediatric Airway Sizing; Pediatric Direct Laryngoscopy; Pediatric Otolaryngology

DEFINITION

• All congenital vascular anomalies that cause compression of the trachea and/or esophagus
• Complete vascular ring: Completely encircles trachea/esophagus
• Incomplete ring: everything else

PRESENTATION

• Common initial presenting symptoms variable:
  • Stridor (biphasic), cyanotic episodes, persistent cough, recurrent pneumonia/URI, recurrent vomiting and dysphagia in the first year of life
  • Severity of symptoms and time of presentation are directly proportional to the tightness of the ring
• On physical exam:
  • Intercostal retractions, hyperextension of head
• Associated anomalies in up to 50% of individuals
  • Cardiac: VSD, ToF, PDA
  • TEF, Cleft lip/palate, SGS
  • 22q11, T21, CHARGE

ANATOMY

• Complete vascular rings
  • Double aortic arch
    • Historically recognized as most common and most symptomatic vascular ring
    • One side is generally atretic and the descending aorta and ductus are seen opposite the dominant arch
    • Right sided dominant in 80% of cases
    • 
  • Right aortic arch + aberrant left subclavian artery + diverticulum of kommerell + ligamentum arteriosum/ductus arteriosus
    • Diverticulum of Kommerell: retroesophageal outpouching. Ectatic or aneurysmal dilation at the origin of the subclavian artery. Initially described in Left aortic arch. Often referred to as retroesophageal diverticulum. The diverticulum is an important factor in causing compressive symptoms. If there is no diverticulum there is possibly a different etiology for breathing or swallowing issues.
    • All right aortic arch anomalies can be associated with cardiac defects: truncus arteriosus, tetralogy of fallot, tricuspid atresia and sometimes chromosomal anomalies
    • 
  • Right aortic arch with mirror branching + left ligamentum arteriosum/ductus arteriosus from descending aorta posterior to the esophagus
    • This is a rarer entity and most right aortic arches with mirror branching do not form a ring as the ductus arises from the left brachiocephalic artery
    • 
  • Left aortic arch + aberrant right subclavian artery + diverticulum of kommerell + right ligamentum arteriosum/ductus arteriosus
    • There are many in cardiothoracic literature who do not see this as a compressive entity and are reluctant to operate and treat an aberrant right subclavian artery.
    • There are case reports of repair leading to resolution of dysphagia
    • 
• Incomplete vascular rings/False vascular rings
  • Right aortic arch + aberrant left subclavian artery + right ligamentum arteriosum/ductus arteriosus
    • Asymptomatic
    • 
  • Left aortic arch + aberrant right subclavian artery + left ligamentum arteriosum/ductus arteriosus
    • 0.3-0.5% incidence (majority asymptomatic) – most common aortic anomaly
    • Usually isolated
    • 35% prevalence in T21 (Fehmi 2013)
    • 
  • Right circumflex aorta
    • Degree of compression dictated by location of ductus arteriosus. Requires aorta uncrossing procedure.
    • 
  • Innominate artery compression
    • Children generally present with symptoms consistent with vascular ring – cough and apnea
    • Almost all resolve by age 2 without treatment
    • No operation warranted unless >80% compression
    • 
  • Pulmonary artery sling
    • Very rare. <5% of vascular rings
    • Children present with difficulty with development, minimal anterior esophageal compression, severe airway compression
    • 50% have hypoplasia of the distal trachea and/or complete cartilaginous rings
    • 

DYSPHAGIA LUSORIA

• Dysphagia lusoria is a relatively rare condition involving a vascular ring (usually an aberrant right subclavian as this is the most common aortic anomaly). As children these patients are asymptomatic but develop worsening dysphagia later in adulthood. Presumably this is secondary to increasing calcification and blood pressure

NON-RECURRENT RECURRENT LARYNGEAL NERVE

• As the LEFT recurrent laryngeal nerve courses around the aorta and the RIGHT recurrent laryngeal nerve courses around the innominate artery care must be taken in neck surgery for patients with known aortic anomalies. In patients with these anomalies the recurrent laryngeal nerve is often non-recurrent. This is particularly the case for the LEFT recurrent laryngeal nerve in a right aortic arch and the RIGHT recurrent laryngeal nerve in an aberrant left subclavian artery.
• Nonrecurrent recurrent laryngeal nerve

DIAGNOSTIC TESTING (Polleto 2017, Hanneman 2017)

• No standardized diagnostic work-up
• Referral and imaging based on symptom pattern
• Otolaryngology often consulted secondary to airway concerns and dysphagia
• CXR
  • 95% have abnormalities (air trapping, right sided aortic arch)
  • Often read as normal
• Barium Swallow
  • Pro:
    • Historical test of choice in combination with angiography
    • Lateral view will show indentations on the posterior wall of the esophagus
    • May rule out vascular ring
  • Con
    • Does not show type of anomaly and 3D relationships
    • Difficult to perform
• Echocardiogram
  • Pro
    • Highly sensitive
    • No radiation – may work well as initial imaging test
  • Con
    • Operator dependent
    • Difficult for surgical team to assess relationships
  • Prenatal echocardiogram (Evans 2016)
    • Increasing importance in diagnosis
    • One study showed 77% Right aortic arch with aberrant left subclavian, 20% Double aortic arch, 3% pulmonary artery sling
      • Historically Double aortic arch is the most common vascular ring – likely because it is the most symptomatic
    • Most of these children will be asymptomatic – cannot predict course
• Conventional angiography
  • Pro:
    • High resolution
    • Complex relationships
    • Real time information
  • Con:
    • Invasive
    • Contrast
    • No 3D structure
    • Limited to the lumen
• Computed tomography (CT) scan
  • Pro:
    • Complete assessment of tracheal and esophageal compression simultaneously
    • Can be performed fast without anesthesia of breath holding
  • Con:
    • Radiation exposure
• Magnetic Resonance Angiography (MRA)
  • Pro:
    • No radiation exposure
    • Provides detailed relationships
    • CINE MRI may have a potential contribution
  • Con:
    • Time consuming
    • Anesthetic
    • Gadolinium contrast
• Endoscopy
  • Not universally performed, no clear sensitivity or specificity
  • Look for arterial pulsations, erythema and edema of the tracheal wall
  • Manual compression – the rigid scope can be used to compress the anomalous vessel from the trachea by lever action with monitoring of peripheral pulses with pulse oximetry
  • Differential and comorbidities to be attentive to:
    • Laryngeal cleft, complete cartilaginous rings, laryngomalacia, subglottic stenosis, tracheomalacia, mediastinal mass, esophageal motility, GERD

Endoscopy findings by location summarized from findings (Furuya 2010)

TREATMENT

• General treatment principles
  • Rule out other possible causes of symptoms
  • Each anomaly has a unique repair procedure performed by cardiothoracic surgery. In general, the ligamentum/arteriosum is severed, the diverticulum of Kommerell removed and the vessels rearranged as necessary. This sometimes involves aortopexy and/or cardiopulmonary bypass.
  • The decision for surgery is a joint decision between multiple actors. It will often not be clear that dysphagia or airway difficulty are a direct result of vascular compression. Ultimately, cardiothoracic surgery is responsible to the decision to proceed with treatment but it often involves discussions with pulmonology, cardiology, otolaryngology and the family.
  • Mild symptoms may sometimes be observed (Loomba 2016)
  • Surgical outcomes are generally very good (70-90% resolution). Dysphagia almost always resolves and persistent problems after initial repair are often related to tracheal anomalies. Persistent post-operative aerodigestive concerns range from mild stridor to tracheostomy and positive pressure ventilation.

REFERENCES/SUGGESTED READING

Uptodate. Accessed 3/14/19

Backer, Carl L., et al. “Vascular Rings.” Seminars in Pediatric Surgery, vol. 25, no. 3, 2016, pp. 165–175., doi:10.1053/j.sempedsurg.2016.02.009.

Evans, William N., et al. “Vascular Ring Diagnosis and Management.” World Journal for Pediatric and Congenital Heart Surgery, vol. 7, no. 6, 2016, pp. 717–720., doi:10.1177/2150135116661279.

Fehmi Yazıcıoğlu H, Sevket O, Akın H, Aygün M, Özyurt ON, Karahasanoğlu A. Aberrant right subclavian artery in Down syndrome fetuses.  2013;33(3): 209–213. Crossref, Medline, Google Scholar

Furuya, María E.y., et al. “Endoscopy for the Initial Suspicion of Vascular Rings in Tracheoesophageal Compressions: Correlation with Surgical Findings.” Pediatric Pulmonology, 2010, doi:10.1002/ppul.21216.

Hanneman, Kate, et al. “Congenital Variants and Anomalies of the Aortic Arch.” RadioGraphics, vol. 37, no. 1, 2017, pp. 32–51., doi:10.1148/rg.2017160033.

Jones, Trahern W., and Michael D. Seckeler. “Use of 3D Models of Vascular Rings and Slings to Improve Resident Education.” Congenital Heart Disease, vol. 12, no. 5, 2017, pp. 578–582., doi:10.1111/chd.12486.\

Loomba, Rohit. “Natural History of Asymptomatic and Unrepaired Vascular Rings: Is Watchful Waiting a Viable Option? A New Case and Review of Previously Reported Cases.” Children, vol. 3, no. 4, 2016, p. 44., doi:10.3390/children3040044.

Poletto E, Mallon MG, Stevens RM, Avitabile CM.  Imaging Review of Aortic Vascular Rings and Pulmonary Sling.  J Am Osteopath Coll Radiol.  2017;6(2):5-14.

Priya, Sarv, et al. “Congenital Anomalies of the Aortic Arch.” Cardiovascular Diagnosis and Therapy, vol. 8, no. S1, 2018, doi:10.21037/cdt.2017.10.15.

Savla, Jill J., and Paul M. Weinberg. “Editorial on ‘Vascular Ring Diagnosis and Management: Notable Trends over 25 Years.’” Translational Pediatrics, vol. 6, no. 2, 2017, pp. 83–85., doi:10.21037/tp.2017.03.05.

Smith, R. J. H., et al. “Congenital Vascular Anomalies Causing Tracheoesophageal Compression.” Archives of Otolaryngology - Head and Neck Surgery, vol. 110, no. 2, 1984, pp. 82–87., doi:10.1001/archotol.1984.00800280016006.

Son, Jacques A.m. Van, et al. “Surgical Treatment of Vascular Rings: The Mayo Clinic Experience.” Mayo Clinic Proceedings, vol. 68, no. 11, 1993, pp. 1056–1063., doi:10.1016/s0025-6196(12)60898-2.

Tola, Hasan, et al. “Assessment of Children with Vascular Ring.” Pediatrics International, vol. 59, no. 2, 2016, pp. 134–140., doi:10.1111/ped.13101.