Paraplegia after thoracoabdominal aortic aneurysm repair: is dissection a risk factor?

The association between aortic dissection and paraplegia or paraparesis (P/P) after thoracoabdominal aortic aneurysm repair is not clear.

Six hundred sixty patients underwent thoracoabdominal aortic aneurysm repair from 1986 through 1995 using selective atriodistal bypass, liberal reattachment of critical intercostal arteries, moderate heparinization, and permissive mild hypothermia. Dissection was present in 163 patients (24.7%) and absent in 497 (75.3%).

Early mortality occurred in 7.4% overall, and did not differ between patients with nondissection, acute dissection, or chronic dissection. The incidence of P/P was 5.4% overall, 5.5% without dissection, and 5.0% with dissection. The risk of P/P for acute versus chronic dissection was 19% versus 2.9%, respectively (p = 0.011). Rupture and Crawford extent II were predictive of the development of P/P. In patients at high risk for P/P (ie, Crawford extent I or II), atriodistal bypass reduced the intercostal artery ischemic time, and reattachment of critical intercostal arteries (T8 to L1) reduced the incidence of P/P.

Acute dissection increases the risk of P/P after thoracoabdominal aortic aneurysm repair; using contemporary methods, however, chronic dissection does not increase the risk of postoperative P/P. Critical intercostal artery reattachment and atriodistal bypass are beneficial in patients undergoing extensive repairs.