Aneurysm of the aberrant right subclavian artery – a case report

BACKGROUND: The right subclavian artery, originating not from the brachiocephalic trunk but directly from the aortic arch, is a rare anatomical abnormality. ‘Arteria lusoria’ is the accepted name of the retroesophageal right subclavian artery. Such a vessel location, between the vertebral column and the esophagus, determines its course to the right. This defect may be asymptomatic, found during autopsy or coincidentally during diagnostic procedures. However, it may also be symptomatic. The course of this major blood vessel in the limited anatomical space may cause symptoms of mediastinal organ compression. The aim of this paper was to present two cases of abnormal anatomical course of the right subclavian artery and its aneurismal dilation. In this study, CT scans of the saccular aneurysm of the retroesophageal right subclavian artery were used: of a male patient diagnosed at Euromedic Diagnostics in Olsztyn and of a female patient, from the resources of the Radiological Dept. at MSWiA Hospital in Olsztyn CASE REPORTS: An 85-year-old female was admitted to Hospital ER for congestive heart failure decompensation. Her chest X-ray revealed a round mass in the upper right mediastinum. Chest CT confirmed the presence of a saccular aneurysm of the lusory artery, 6.5 cm in diameter, partially filled with thrombotic material. The patient died in hospital from myocardial infarction that was not related to the aneurysm. A 61-year-old male patient had a chest X-ray which showed a round opacity on the apex of the right lung. The diagnostic process comprised also chest computed tomography. The examination showed an anomalous origin of the right subclavian artery, with aneurysmal dilation and compression of the oesophagus and of the trachea. An intraluminal thrombus was found. The patient remained under observation till the next CT examination, 6 months later. CONCLUSIONS: The presented rare cases of arteria lusoria aneurysm are not only casuistic reports. They also show the value of modern MDCT diagnostics. Multi detector CT examinations allow for a proper evaluation of the vascular anomalies in mediastinum. The analysis of vascular pathologies and accompanying compression of adjacent organs makes further treatment possible.