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The applicability of chimney grafts in the aortic arch.

AIM
Proximal fixation is often limiting for thoracic endovascular aortic repair (TEVAR) and the stent graft may need to cover the origin of the arch branch vessels. Chimney grafts have been proposed to preserve flow into over stented branches during urgent TEVAR. The aim of this report is to share our initial experience of this technique.


METHOD
Eleven patients underwent urgent TEVAR combined with a chimney graft between January 2004 and April 2009. The indications included acute complicated type B dissection (N. = 2), ruptured aneurysms of the aortic arch (1) and descending aorta (2), traumatic aortic transaction (1), aortoesophageal fistula (1) and accidental over stenting of the left carotid artery during TEVAR (4). Chimney grafts were implanted into the innominate (N. = 3), left carotid (7) and left subclavian (1) arteries. Mean length of follow up was 20 months.


RESULTS
All chimney grafts were successfully implanted. Two patients developed a primary proximal type I endoleak: one leak was successfully coil embolized, the other awaits treatment. One paraplegia was reversed by spinal drainage but two months later, this patient presented with a contained rupture and underwent successful conversion to open repair. No other postoperative aneurysm expansion has occurred and the chimney grafts remain patent. The only aneurysm related death occurred in a patient with an unrecognized chronic occlusion of his right carotid artery who received a left carotid chimney graft and suffered from a lethal stroke.


CONCLUSION
Chimney grafts in the supra-aortic branches seem feasible and may facilitate urgent TEVAR in patients with an inadequate proximal neck.