Aberrant Right Subclavian Artery

An African American baby girl was noted to have noisy breathing at birth. The infant had inspiratory stridor while awake and no audible stridor while asleep. Birth weight was 3.20 kg (7.11 lb). She had been formula fed for the first 2 weeks of life and had intermittently vomited after feedings.

Prenatal and postnatal histories were otherwise noncontributory. She had an 18-month-old sibling with reflux and laryngomalacia. The infant was afebrile; heart rate was 168 beats per minute, respiration rate was 46 breaths per minute, and oxygen saturation was 100% on room air. She did not appear to be in distress. The lungs were clear bilaterally. The remainder of the examination findings were unremarkable.

A complete blood cell count and electrolyte levels were normal. A chest radiograph was normal. A barium swallow study was performed because of concern for a congenital airway anomaly. Other conditions considered in the differential diagnosis included a vascular ring and sling. The barium swallow study revealed tracheal and esophageal compression, which was consistent with an aberrant right subclavian artery. (The buttons on the baby’s gown are also visible in the image.)

Also known as arteria lusoria, an aberrant right subclavian artery is one of the most commonly seen congenital anomalies of the aortic arch. The incidence is about 0.4% to 2.0% in the general population; there appears to be a moderately strong female predominance.^1-4

Although often asymptomatic, an aberrant right subclavian artery is an important cause of respiratory problems in infants. Patients may present with chronic cough, wheezing, persistent dysphagia, regurgitation, or tachypnea.³ The clinical picture closely mimics that of uncontrolled asthma; however, patients do not respond to bronchial dilators and may respond only minimally to inhaled corticosteroids.

In children with an aberrant right subclavian artery, chest radiographs and oxygen saturation as measured by pulse oximetry are almost always normal. CT scans are often used to make a definitive diagnosis. Although rare, serious complications, such as arterioesophageal and arteriotracheal fistulae, can occur in undiagnosed cases of an aberrant right subclavian artery.¹

Treatment often involves surgical correction of the underlying anatomy. This generally consists of ligation of the aberrant vessel and a reconstructive bypass via open thoracotomy. ⁴ However, video-assisted thorascopic surgery also has been used. There is currently no concensus on which surgical method is best; both procedures have a low rate of mortality.

This baby’s mother refused surgery. The infant is currently being treated with antireflux medications, which appear to be controlling her symptoms.

References:

REFERENCES:
1. Kopp R, Wizgall I, Kreuzer E, et al. Surgical and endovascular treatment of symptomatic aberrant right subclavian artery (arteria lusoria). Vascular. 2007;15:84-91.
2. Fisher RG, Whigham CJ, Trinh C. Diverticula of Kommerell and aberrant subclavian arteries complicated by aneurysms. Cardiovasc Intervent Radiol. 2005;28:553-560.
3. Ramaswamy P, Lytrivi ID, Thanjan MT, et al. Frequency of aberrant subclavian artery, arch laterality, and associated intracardiac anomalies detected by echocardiography. Am J Cardiol. 2008;101:677-682.
4. Atay Y, Engin C, Posacioglu H, et al. Surgical approaches to the aberrant right subclavian artery. Tex Heart Inst J. 2006;33:477-481.