Thoracoabdominal Aneurysm Repair

Aneurysms that extend from the descending thoracic aorta into the abdomen and also those that involve the visceral segments of the upper abdominal aorta are traditionally classified as thoracoabdominal. Besides the surgical exposure difficulties associated with repair of these aneurysms, the temporary interruption of renal, splanchnic, and perhaps even spinal cord flow introduces a number of potential complications that makes surgical repair of these aneurysms a daunting task. The exact incidence of thoracoabdominal aneurysms is unknown, but population studies suggest a prevalence at least a log fold less than the more common infrarenal abdominal aortic aneurysm. The poor prognosis of nonsurgically treated aneurysmal disease of the descending thoracic and abdominal aortas has been reasonably well established. Few patients with thoracoabdominal aneurysms survive beyond five years as a result of not only aneurysm rupture but also death from advanced co-morbid medical disease. Since the first successful report of thoracoabdominal aneurysm repair over 40 years ago, a number of remarkable contributions have been made in the field. These advances have led to a significant decline in operative mortality as well as procedure related morbidity. Spinal cord ischemia remains a perplexing and devastating complication following thoracoabdominal aneurysm repair. A number of surgical adjuncts have been developed over the years to reduce the incidence of cord ischemic complications, yet a great deal of controversy still exists with regards to the optimal protective strategy. A description of the incidence, natural history, and classification of thoracoabdominal aneurysms, along with associated repair techniques centered on reducing spinal cord ischemic complications will form the basis for this review.