The close proximity of the arch vessels to the origin of many thoracic aortic aneurysms (TAA) may result in placement of the stent struts across the left subclavian or carotid ostia. The purpose of this study is to determine the incidence and impact of transaortic arch vessel fixation during thoracic aortic stent graft deployment for the treatment of descending TAA. From May 1997 to July 2000, 20 patients (10 men, 10 women, mean age 82 years) with descending TAA were treated in the operating room with endoluminally placed stent grafts secured proximally to the thoracic aorta with a long (15-mm) uncovered stent segment (Talent LPS). Pre- and post-operative angiograms and IV contrast-enhanced spiral CT scans were performed in all cases. Follow-up contrast CT scans were obtained at 1, 3, 6, and 12 months and yearly thereafter to assess the adequacy of repair and to determine stent position and arch vessel patency. We found that thoracic aortic endograft fixation across the left aortic arch vessels occurs frequently during device placement and is associated with no early morbidity. Long-term follow-up is necessary to ensure that there are no late sequelae.