Morphology of aortic arch pathology: implications for endovascular repair.

PURPOSE: To present a detailed description of aortic arch morphology in patients with aneurysm and dissection undergoing thoracic endovascular aortic repair (TEVAR).

METHODS

Morphological assessment of the aortic arch was performed in a consecutive series of patients undergoing TEVAR between November 2003 and April 2009. In the absence of standardized reporting criteria, any patient requiring overstenting of the left subclavian artery (LSA) was considered to have pathology of the aortic arch. In all, the arch morphology of 49 patients (31 men; mean age 70 years, range 43-86) was analyzed (25 aneurysms and 24 dissections). The proximal landing site of the intended stent-graft was Ishimaru zone 0 in 2 (4%) patients, zone 1 in 11 (22%), and zone 2 in 36 (74%). Measurements were made of the aortic arch diameters and angulation and the orientation and diameters of the supra-aortic trunks from 3-dimensional reconstructions of computed tomography scans.

RESULTS

The diameter of the aortic arch increased as it approached the aortic root (mean 38.9+/-6.4 mm at the sinotubular junction versus 30.7+/-16.6 mm at the left subclavian artery (LSA). Mean angulation of the arch at the level of the LSA was 117 degrees +/-23 degrees . Five (10%) patients had a common origin of the innominate artery and left common carotid artery (LCCA). The distance between the LCCA and the LSA was <15 mm in 80%; 37 (80%) had clock-face positions of the LCCA and LSA ostia within 15 degrees of each other. There was no statistical difference in any measurements between the aneurysm and dissection patients.

CONCLUSION

In this cohort, morphology was similar for patients with aneurysm or dissection. The distance between the LCCA and the LSA in the majority of cases was shorter than the recommendation for an adequate proximal landing zone. This data may assist in the development of stent-grafts for the aortic arch.