Endovascular treatment of thoracic aortic aneurysms: results of the phase II multicenter trial of the GORE TAG thoracic endoprosthesis.

OBJECTIVE: A decade after the first report of descending thoracic aortic aneurysm (DTA) repair with endografts, a commercial device is yet to be approved in the United States. The GORE TAG endoprosthesis, an investigational nitinol-supported expanded polytetrafluoroethylene tube graft with diameters of 26 to 40 mm, is the first DTA device to enter phase II trials in the United States and has been used worldwide for a host of thoracic pathologies.
METHODS: A multicenter prospective nonrandomized phase II study of the GORE TAG endoprosthesis was conducted at 17 sites. Enrollment was from September 1999 to May 2001. Preoperative workup included arteriography and spiral computed tomography scans of the chest, abdomen, and pelvis. Follow-up radiographs and computed tomography scans were obtained at 1, 6, and 12 months and yearly thereafter.
RESULTS: A total of 139 (98%) of 142 patients had a successful implantation of the device. Inadequate arterial access was responsible for the 3 failures. The mean DTA size was 64.1 +/- 15.4 mm. Men slightly outnumbered women (57.7%), with an average age of 71 years, and 88% of the patients were white. Ninety percent were American Society of Anesthesiologists category III or IV. One device was used in 44% of patients, and 56% required two or more devices to bridge the thoracic aorta. The left subclavian artery was covered in 28 patients, with planned carotid-subclavian transposition. The procedure time averaged 150 minutes, estimated blood loss averaged 506 mL, intensive care unit stay averaged 2.6 days, and hospital stay averaged 7.6 days. Within 30 days, 45 (32%) patients had at least 1 major adverse event: 5 (4%) experienced a stroke, 4 (3%) demonstrated temporary or permanent paraplegia, 20 (14%) experienced vascular trauma or thrombosis, and 2 (1.5%) died. Mean follow-up was 24.0 months. Four patients had aneurysm-related deaths. Three patients underwent endovascular revisions for endoleak. No ruptures have been reported. Twenty wire fractures have been identified in 19 patients; 18 (90%) of these occurred in the longitudinal spine, and only 1 patient required treatment. At 2 years, aneurysm-related and overall survival rates are 97% and 75%, respectively.
CONCLUSIONS: The GORE TAG thoracic endoprosthesis provides a safe alternative for the treatment of DTAs, with low mortality, relatively low morbidity, and excellent 2-year freedom from aneurysm-related death. Longitudinal spine fractures have so far been associated with rare clinical events.