Anomalous origin of the right subclavian artery was first described in 1794 by David Bayford. He discovered it incidentally in a postmortem study of 62 years old patient who had a history of dysphagia. He then gave the term lusus naturae which means dysphagia by freak of nature. In 1936, Burchard Kommerell described an aortic diverticulum for the first time in a living patient [1]. Burchard described KD as saccular aneurysmal dilatation of aorta arch at the origin of an aberrant subclavian artery [2] [3].

A 68-year-old female with history of hypertension (HTN), hyperlipidemia, diabetes mellitus (DM) presented to the emergency department with chief complaints of chest pain and sore throat of four days duration. Initially, she had intermittent chest pain for about two weeks, which was sharp, radiating to upper back and went away without any treatment. She also had complained of a long standing history of intermittent shortness of breath and dysphagia. She had no relief of symptoms and presented to the emergency department. Initial electrocardiogram (EKG) in the emergency department showed straightening of and biphasic T waves in anterior leads (V1, V3, V4, and V5) and T wave inversions on repeat EKG. Patient was admitted to the hospital for further management.

During hospitalization her troponins continued to rise in the hospital resulting in cardiac catheterization which showed significant mid left anterior descending (LAD) stenosis, which was subsequently stented. Subsequent workup consisted of chest X ray, barium esophagram and a computed tomography (CT) scan of the neck. Chest X-ray showed prominent right aortic arch and slight deviation of trachea to left side (Figure 1) (Figure 2).

Barium studies showed significant narrowing of esophagus and indentation of right lateral border of esophagus (Figure 3) (Figure 4). CT scan of soft tissue of neck revealed enhancing mass within carotid space concern for carotid body tumor, and right aortic arch with ALSA consistent with KD causing narrowing of the airway and esophagus at the thoracic inlet (Figure 5) (Figure 6) (Figure 7) (Figure 8) (Figure 9) (Figure 10) (Figure 11).

The differential diagnosis considered were non-ST elevation myocardial infarction (NSTEMI), Streptococcal pharyngitis, right aortic arch with ALSA demonstrating a diverticulum of Kommerell with a diameter of 2.5 cm, and neoplasm of carotid body.

The patient was treated as NSTEMI with aspirin, heparin and underwent cardiac catheterization. Coronary angiogram revealed obstruction of left anterior descending artery (>95%) and underwent successful percutaneous coronary transluminal angioplasty and placement of bare metal stent in LAD. A course of cephalexin was prescribed for her pharyngitis. The patient was discharged on regimen of atorvastatin, aspirin, toprol, lisinopril, and clopidogrel. The patient was referred to vascular surgeon for KD but refused surgical intervention at this point.

Kommerell diverticulum is a rare congenital aortic arch anomaly with an incidence of 0.5–2.0% in normal population. There are two variants that are commonly described in literature. Left-sided aortic arch with aberrant right subclavian artery (ARSA prevalence 0.5–2.0%) or right aortic arch with aberrant left subclavian artery (prevalence 0.05–0.1%) [3]. Kommerell diverticulum occurs in a number of anomalies of aortic arch system. An aberrant subclavian artery may be located posterior to esophagus (80%), runs between esophagus and trachea (15%), anterior to trachea (5%) [4]. A right-sided aortic arch is associated with deletion of 22q11 chromosome with 24% incidence [5]. Most of the patients with KD are asymptomatic, found incidentally on imaging studies of the chest. Common symptoms of KD include dysphagia, cough, chest pain and stridor due to extrinsic compression of esophagus or tracheobronchial tree by the KD or dilatation of an aberrant subclavian artery [1] [3]. Dysphagia is the most common symptom with KD, termed dysphagia lusoria [6]. Complications of KD include atherosclerosis, embolism, rupture and dissection [7]. The most valuable diagnostic studies include barium swallow esophagram, CT scan and cardiac magnetic resonance imaging (MRI) scan which demonstrate a diverticulum of Kommerell and compression of esophagus or trachea. Standard surgical treatment has not been established being a rare entity. Treatment is surgical resection of the diverticulum regardless of the size because of risk of rupture (19%) which is associated with high mortality [8]. The mean size associated with rupture was 5.8 cm [5].

Kommerell diverticulum (KD) is a rare cause of dysphagia with distinct radiological features. Subtle findings on a chest X-ray may help in the diagnosis. Vascular anomalies such as KD should be considered as differential diagnosis in patients with chronic cough or dysphagia when other causes have been ruled out.

1. van Son JA, Konstantinov IE. Burckhard F. Kommerell and Kommerell's diverticulum. Tex Heart Inst J 2002;29(2):109–12.   [Pubmed]    
2. Ota T, Okada K, Takanashi S, Yamamoto S, Okita Y. Surgical treatment for Kommerell's diverticulum. J Thorac Cardiovasc Surg 2006 Mar;131(3):574–8.   [CrossRef]   [Pubmed]    
3. Mossad E, Farid I, Youssef G, Ando M. Diverticulum of Kommerell: a review of a series and a report of a case with tracheal deviation compromising single lung ventilation. Anesth Analg 2002 Jun;94(6):1462–4.   [CrossRef]   [Pubmed]    
4. Rosa P, Gillespie DL, Goff JM, O'donnell SD, Starnes B. Aberrant right subclavian artery syndrome: a case of chronic cough. J Vasc Surg 2003 Jun;37(6):1318–21.   [CrossRef]   [Pubmed]    
5. Cinà CS, Althani H, Pasenau J, Abouzahr L. Kommerell's diverticulum and right-sided aortic arch: a cohort study and review of the literature. J Vasc Surg 2004 Jan;39(1):131–9.   [CrossRef]   [Pubmed]    
6. Brown DL, Chapman WC, Edwards WH, Coltharp WH, Stoney WS. Dysphagia lusoria: aberrant right subclavian artery with a Kommerell's diverticulum. Am Surg 1993 Sep;59(9):582–6.   [Pubmed]    
7. Kouchoukos NT, Masetti P. Aberrant subclavian artery and Kommerell aneurysm: surgical treatment with a standard approach. J Thorac Cardiovasc Surg 2007 Apr;133(4):888–92.   [CrossRef]   [Pubmed]    
8. Austin EH, Wolfe WG. Aneurysm of aberrant subclavian artery with a review of the literature. J Vasc Surg 1985 Jul;2(4):571–7.   [CrossRef]   [Pubmed]    
9. Cinà CS, Althani H, Pasenau J, Abouzahr L. Kommerell's diverticulum and right-sided aortic arch: a cohort study and review of the literature. J Vasc Surg 2004 Jan;39(1):131–9.   [CrossRef]   [Pubmed]