Endovascular Stent-Grafts for Descending Thoracic Aortic Aneurysms and Acute Type B Aortic Dissections
Because patients with descending thoracic aortic aneurysms tend to be elderly and have multiple other co-morbidities, conventional open surgical repair of these life-threatening thoracic aortic problems is associated with substantial morbidity and mortality. Therefore, the CV Surgery and CVRI teams at Stanford collaborated to conduct a prospective, nonrandomized clinical trial to assess the feasibility and effectiveness of endovascular stent-graft (S-G) repair. Between 1992 and 1997,103 patients (mean age 69 years) underwent treatment using a custom fabricated “home brew” (self-expanding Z stents, large sheath/dilator/pusher rod delivery system) S-G device. Sixty-two patients (60%) were judged not to be reasonable candidates for an “open” operation. Nineteen patients underwent simultaneous AAA repair. Etiology included atherosclerotic-degenerative aneurysm 62%, giant aortic penetrating ulcer (GAPU) 10%, aortic dissection 8%, chronic traumatic false aneurysm 8%, anastomotic pseudoaneurysm 8%, intramural hematoma (IMH) 3%, and mycotic false aneurysm 2%. Follow-up was 100% complete (average = 22 months, max = 5.3 years). Forty-four patients remained alive and at risk two years after the procedure. Femoral access was achieved in 58%, but retroperitoneal access via the abdominal aorta was required in 30%. An AAA was repaired concomitantly in 19 patients. Immediate complications included obstruction of the aortic arch in one patient, S-G misdeployment in 3%, peripheral arterial injury in 4%, and iatrogenic aortic dissection in 1%. Complete thrombosis of the aneurysm was ultimately achieved in 86 (83%) patients.