Long-term results temper optimism for AAA stent grafts

Results from five-year outcomes studies on stent grafts for aortic aneurysms are good, but not quite good enough. Researchers presenting at the European Congress of Radiology cautioned that endoleaks, migrations, and other complications are still a bit more common than they'd like.

A number of studies posted some mortality, not always related to the AAA itself ?- two patients died from aortic rupture and five from other causes in an Italian study with 81 patients overall, and two died in another study of 25 ?- but complications ran higher. Reports of endoleaks ranged from 9% to 13%, for example.

Researchers from Groningen University Hospital in the Netherlands reported that 1.9% of 209 patients had procedure-related complications, including infections. Thirty-seven patients required secondary interventions, and 18% had suboptimal results related to leaking or stent-graft movement.

The results are typical and acceptable if broken out into procedure-related complications and long-term complications, said Dr. W. Oudkerk. But, overall, the frequency of problems is fairly high.

"Gradually we are decreasing the number of contraindications for this procedure, but the complication rate remains fairly high," said Dr. Martin Mack of Frankfurt, Germany. "In patients who are healthy, with long life expectancy and with no major disease, we advise waiting on this procedure until the results are comparable with open surgery. A 2.1% rate of endograft structural problems is too common."

Much of the mediocre long-term data presented can be attributed to first-generation stent graft models, some no longer used, that were prone to kinking, dislodging, or migrating. Most presenters had used a mix of Talent, Vanguard, Excluder, and Zenith stents. Vanguards, in particular, have been prone to migrating up the proximal neck, said Dr. Claudia Walch of Innsbruck, Austria. The newer Zenith and Excluder models are more rigid and more easily attached to the lumen.