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Technical challenges in endovascular repair of complex thoracic aortic aneurysms.

BACKGROUND
Endovascular aneurysm repair has gained widespread acceptance, and there has been a significant increase in the number of aneurysms treated with stent grafts. However, the endovascular technique alone is often not appropriate for anatomically complex aneurysms involving the neck branches. We used the TAG stent for thoracic aortic aneurysms (TAA), and report our initial results.


PATIENTS AND RESULTS
We deployed 80 TAG stents in 65 patients electively treated with TAA between June 2006 and June 2008. Thoracic endovascular aneurysm repair (TEVAR) was performed in 45 cases of descending aortic aneurysm with no morbidity or mortality. A combination of open surgery and TEVAR was performed in 11 out of 20 cases with aneurysms of the aortic arch. The prior total arch replacement and elephant trunk procedure was performed in 3 cases with dilated ascending aorta, total debranching from ascending aorta with sternotomy in 5, and carotid-carotid artery crossover bypass in 3 cases. Meanwhile, TEVAR with coverage of the left subclavian artery was performed in the remaining 9 distal arch cases. In 3 cases with extremely short necks, a 0.018" guide wire was inserted percutaneously in a retrograde manner through the common carotid artery (CCA) into the ascending aorta to place the stent graft in close proximity to the CCA (wire protection). In 1 of these 3 cases, the TAG stent was deployed through the CCA, and the 0.018" guide wire was used to deliver a balloon-expandable stent in order to restore the patency of the CCA. In arch and distal arch aneurysm cases, perioperative mortality and the incidence of stroke were both 5.0%; dissection of the ascending aorta was seen in one case (5.0%).


CONCLUSION
As treatment for descending aortic aneurysms, TEVAR can replace conventional open repair. However, TEVAR for arch aneurysms has some problems, and further improvement is necessary. (English Translation of Jpn J Vasc Surg 2010; 19: 547-555.).