Aortic Arch Mapping by Computed Tomography for Actual Anatomic Studies in Times of Emerging Endovascular Therapies

Abstract

The latest advances in treatment of aortic arch pathologies increasingly included endovascular technologies. For those purposes, more detailed knowledge about the specific anatomic features are of particular interest, especially with regard on the need for better suitable stent grafts or even development of "off-the-shelf" stents. The study enrolled patients undergoing computed tomography of the chest for other reasons than screening for aortic disease. Patients with aortic pathologies were excluded. Finally, 118 patients were included. Anatomic features of the aortic arch, the supra-aortic branches, distances and takeoff angles as well as specific diameters were assessed and analyzed with respect to the patients height, weight, age, and sex. A significant variability of all measurements was observed. Nonetheless, 4 recurrent types of aortic arch geometry were identified: (1) Classic arch (39%), (2) Gothic arch (39%), (3) Rectangle arch (11.9%), and (4) Plain arch (8.5%). Furthermore, the aortic diameter continuously decreased from the beginning of the ascending aorta during the after 200 mm by 24.8% (31.8 ± 3.6 mm to 23.9 ± 3.1 mm in mean). Distances from the aortic annulus to the supra-aortic branches takeoff points showed significant gender- and age-related differences with larger distances in the older and male (P < 0.001). Observed takeoff angles were 44.9 ± 15.9° for the brachiocephalic trunk, 25.7 ± 15.5° for the left common carotid artery, and 28.8 ± 14.5° for the left subclavian artery. Observed anatomic features were highly variable. It seemed that a "standard aortic arch" does not exist. Until today, the aortic arch as a dynamic and 3-dimensional entity is not fully understood. The development of "off-the-shelf" stents in the near future will be limited by this complexity and variability.