Mapping the Aorta: A New Look at Vascular Anatomy in the Era of Endograft Repair

Aortic anatomy, as learned in medical school, is the bedrock on which surgery was founded and continues to be performed to this day. That said, let me reassure you that this is not an effort at re-engineering that anatomy the reader knows well, but a ‘‘new look’’ is warranted as the aortic surgery field has been (literally) transformed as a result of developments in stent-graft technologies. A new anatomical dimension to the aorta has evolved as we become deeply immersed in a universe populated with terms and concepts that would not even have made sense only 10 or 15 years ago: landing zones, overstenting, and debranching are just a few examples that help define today’s aortic interventional landscape. Through it all, we can be sure of this: aortic surgery will never be the same again, and endograft therapies are here to stay. Unlike conventional operative procedures, endovascular repair unfolds within the confines of the aortic inner space. This endoluminal view has led in turn to a new and different perspective on anatomy that is relevant to the endovascular technologies and treatment strategies available to us in the XXI century. Although Balm et al. were first to suggest a system for recording the site of proximal endograft fixation in the arch by drawing lines through the distal margin of branch vessel ostia, it was Shin Ishimaru who proposed dividing the arch into actual zones that could be used to define precisely the site of proximal fixation of a thoracic endograft during the 2001 First International Summit on Thoracic Aortic Endografting held in Tokyo, Japan. Shortly thereafter, I expanded on these ideas with a sketch of an arch zone map (Fig. 1) that has since been embraced by many around the world and incorporated in several clinical trial protocols. In 2004, Ishimaru (again) expanded the anatomical map, adding zones throughout the length of the descending thoracic aorta using the relationship to spinal vertebral anatomy as designators for the various segments, but this proved somewhat complex and has not enjoyed the popularity of its predecessor. In this editorial, I intend to re-define and further clarify these concepts and offer an allencompassing anatomical zone map that highlights the relevant aspects of aortic anatomy from the perspective of endograft therapy. For the first time, a zone map of the visceral aorta will be introduced as well.