Kommerell Diverticulum: Right Aortic Arch with Anomalous Origin of Left Subclavian Artery and Duplicity of Right Vertebral Artery in a 16-Year-Old Girl.

BACKGROUND Kommerell diverticulum with a right-sided aortic arch is a rare congenital anatomical condition most often observed in adults. A possible etiology of the subclavian artery's anomalous origin would be an abnormality in regression of the fourth primitive aortic arch during embryonic development. CASE REPORT We report on the case of a 16-year-old female patient presenting with complaints of occasional tachycardia and mild non-specific dyspnea after anxiety crises. Physical examination revealed lower amplitude of the pulses in the left upper limb compared to the right upper limb, and difference in blood pressure (BP) values of 80×60 mmHg, and 100×60 mmHg, respectively. Different radiological imaging modalities were performed to elucidate a possible vascular abnormality. Multislice detector computed tomography angiography of the thoracic aorta and supra-aortic trunks showed a right-sided aortic arch and an aberrant origin of the left subclavian artery with a retroesophageal course and dilation of its emergence (Kommerell diverticulum), as well as duplicity of the right vertebral artery (RVA). Considering the actual small diameter of the diverticulum and the absence of dysphagia or severe external esophageal compression analyzed by the esophagogram, vascular surgery was not indicated. Since complications have been described in the literature, the patient must be kept under observation in the future. CONCLUSIONS Congenital vascular alterations, including Kommerell diverticulum with right-sided aortic arch and the aberrant origin of the left subclavian artery, should be suspected in otherwise asymptomatic young patients with few clinical manifestations. Investigation with different imaging methods helps to clarify the vascular abnormalities, to support a possible surgical procedure indication, and to monitor the patients in follow-up.