Arteria lusoria, also known as an aberrant right subclavian artery (ARSA), is a congenital vascular anomaly of the aortic arch in which the right subclavian artery arises directly from the aorta distal to the left subclavian artery, rather than from the brachiocephalic trunk. This variation, occurring in a small percentage of the population, is frequently associated with a Kommerell’s diverticulum, a pouch-like aneurysmal dilation at the origin of the aberrant artery. A recent case at Mohammed VI University Hospital in Oujda involved a 62-year-old patient with exertional dyspnea who underwent thoracic angioscanning for suspected pulmonary embolism, revealing a retro-oesophageal right subclavian artery and a 22 mm Kommerell's diverticulum. In the absence of significant symptoms or complications, a conservative management strategy was chosen, consisting of therapeutic abstention and regular follow-up, with no issues reported to date. Diagnosis is primarily based on thoracic CT imaging, which provides detailed anatomical insights, and treatment varies from observation to surgical or endovascular intervention depending on clinical findings. The management of this anomaly is tailored to each case, considering symptom severity, potential complications, overall health status, and patient preferences.