Aortic arch

The aortic arch is a segment of the aorta that arches from the midline towards posterior and to the left. It presents with three branches. From proximal to distal they are the brachiocephalic trunk, the left common carotid artery, and the left subclavian artery. There are several anatomical variations of the branches of the aortic arch.

There is no clear anatomical landmark to denote the ending of the ascending aorta and the beginning of the aortic arch, as there is no clear anatomical landmark to denote the ending of the aortic arch and the beginning of the descending aorta. Anatomists use as a reference a horizontal plane that passes through the angle of Louis. Since this plane also separates the inferior from the superior mediastinum, the aortic arch is found in the superior mediastium, while the ascending and descending aorta are found in the inferior mediastinum.

Aortic arch and branches

Heart - Anterior view  Click on the image for a larger version.

The aortic arch has anatomical relations with the bifurcation of the trachea, the pulmonary trunk and its bifurcation, and the left brachiocephalic vein. In its inferior surface, the aortic arch in the adult has the embryological remnant of the ductus arteriousus, called the ligamentum arteriosum.

The term "aortic arch" was coined and first used by Lorenz Heister (1683 1785) 

Image property of: CAA.Inc.Artist: Victoria G. Ratcliffe