Challenges of endovascular tube graft repair of thoracic aortic aneurysm: Midterm follow-up and lessons learned

Objectives: Endovascular stent-graft repair has great potential in treatment of thoracic aortic aneurysms. This study analyzed a single center's experience with first-generation commercially produced thoracic stent grafts used to treat descending thoracic aortic aneurysms. Methods: Over 58 months 84 patients underwent endovascular stent-graft repair of descending thoracic aortic aneurysms; 22 patients received the Gore TAG stent graft, and 62 patients received the Talent thoracic endovascular stent-graft system. Each patient was enrolled in one of three distinct US Food and Drug Administration trials at Mount Sinai Medical Center in accordance with strict inclusion and exclusion criteria, including suitability for open surgery, aneurysm anatomy, and presence of comorbid medical illness. Mean age of this cohort was 71 +/- 12 years. There were 54 men and 30 women, and 74 (88%) had three or more comorbid illnesses. Primary technical success was achieved in 76 patients (90%). Mean follow-up was 15 months (range, 0-52 months). Results: Successful aneurysm exclusion was achieved in 69 patients (82%). Major procedure-related or device-related complications occurred in 32 patients (38%). There were six proximal attachment failures (8%), four distal attachment failures (6%), one intergraft failure (1%), two mechanical device failures (3%), five periprocedural deaths (6%), and five late aneurysm ruptures (6%). At 40 months, overall survival was 67% (+/-10%), and freedom from rupture or from type I or type III endoleak was 74% (+/-10%). Conclusion: While promising, this midterm experience with commercially available devices highlights the shortcomings of current stent-graft technology. Three significant advancements are required to fulfill the potential of this important treatment method: a stent graft with a durable proximal and distal fixation device, enhanced engineering to accommodate high thoracic aortic fatigue forces, and a mechanism to adapt to aortic arch and visceral segment branches to enable treatment of lesions that extend to or include these vessels.