Right-sided Aortic Arch with Aberrant Left Subclavian Artery arising from Kommerell's Diverticulum: A case report.

Right-sided aortic arch, first documented by Fioratti and Aglietti in 1763, is a rare variant of the thoracic vascular anatomy present in about 0.1% of the adult population. In half of these cases the left subclavian artery is also aberrant. The aberrant left subclavian artery usually originates from a conical dilatation near its origin from the aorta also known as "Kommerell's diverticulum." Fewer than 80 of these cases have been reported in the literature as far as our web search is concerned. It is usually asymptomatic and diagnosed incidentally during adulthood. We are presenting a 56 years old male patient presented with right side chest and shoulder pain of 1 week duration. The pain exacerbated with motion of the right upper extremity and radiates to his lower back. However, he had no history of cough, shortness of breath, syncope, and dysphagia. The vital signs were in normal range. Pulmonary and cardiovascular exam were unremarkable. The complete blood count (CBC), electrocardiogram (EKG), and echocardiography showed no abnormality. In the adult population a right-sided aortic arch with an aberrant left subclavian artery arising from Kommerell's diverticulum is a rare occurrence often asymptomatic unless aneurysmal disease or compression of mediastinal structures ensues. Even though it is rare and at times an incidental finding, the condition is clinically relevant because of the morbidity caused by the complications. We report a case of Kommerell's Diverticulum of an aberrant left subclavian artery in an adult patient with a right-sided aortic arch. Right-sided aortic arch with aberrant left subclavian artery arising from Kommerell's Diverticulum is quite rare and may remain asymptomatic. On times it may cause symptoms in adulthood often as a result of early atherosclerotic changes of the anomalous vessels, dissection, or aneurysmal dilatation with compression of adjacent structures causing dysphagia, dyspnea, cough, or chest pain. Even though there are no general guidelines for the management of this condition patients need to be informed about the nature and possible outcomes of their condition. Close follow up of asymptomatic patients is one option of management until there are situations which require consideration of surgical intervention.