MDCT Evaluation of Variations in branching patterns of aortic arch: Study of 830 Indian patients

Abstract

Objectives : The aim was to determine the prevalence of various variations in the branching pattern of the aortic arch. Material and Methods : 830 Indian patients were included in the study, who had undergone neck and chest CT between Dec 2015 and May 2016, with the exclusion of patients with congenital cardiac anomalies. Results : Of 830 patients, 694 (83.6 %) patients were observed to have the classic three-vesseled branching pattern of the aortic arch, i.e. the brachiocephalic trunk, left common carotid artery and left subclavian artery arising from right to left, with brachiocephalic trunk further dividing into right common carotid and right subclavian arteries. Variations in branching pattern were seen in the remainder 136 (16.3 %) patients. It was also noted that out of the 136 patients with variant branching patterns, 91 (66 %) were females, and the rest were males. The most common variation was the origination of the left common carotid artery from the brachiocephalic trunk, i.e. two-vesseled arch , which was observed in 79 (9.5 %) cases. In 26 (3.1 %) cases, four-vesseled arch was seen, which is direct origin of left vertebral artery from the aorta. 5 (0.6 %) patients had aberrant right subclavian artery . Conclusions : Variations in the branching pattern of the aortic arch are quite common. It is especially important that head and neck surgeons and interventional radiologists should be aware of these aortic arch variations. Contrast-enhanced CT imaging is a reliable method for demonstrating anatomical features and variations of the aortic arch.