Early Aortic Aneurism Stent Repairs Carries Risk

A new study has found that first-generation stent grafts used for endovascular repair of abdominal aortic aneurysms (EVARs) have been associated with high rates of late failures, often leading to death.

Researchers at the European Cobalt Chromium Stent with Antiproliferative for Restenosis Trial (EUROSTAR) data registry center at Catharina Hospital (Eindhoven, The Netherlands) prospectively collected results of EVARs performed on 1,180 patients in Europe between 1994 and 1999 who were followed for up to eight years. Aneurysm diameters were small (between 40 mm and 54 mm) in 581 patients, and 55 mm or larger in 609. Larger aneurysms tended to be associated with older age, diabetes, and diseases of the heart, carotid artery, and lungs, and experienced complications at about twice the rate of those with smaller defects.

First-month mortality was 2.9%, and systemic complications occurred in 12.9% of the patients during their hospitalization. Cumulative survival after eight years was 74.5% among patients with small aneurysms and 49.6% in the remaining subjects. Procedure-related complications observed included endoleak (13 cases per 100 patient-years), stenosis/thrombosis (4.6 cases per 100 patient-years), and stent migration (4.3 cases per 100 patient-years). Structural failure of the stents included fabric tears, fractures caused by metal fatigue, breakdown of polypropylene sutures, and insufficient fixation. The findings were reported in the January 2007 edition of the Archives of Surgery.

"Patients treated with the first generation of stent grafts will need lifelong surveillance because of a considerable risk of late complications,” concluded lead author Dr. Lina J. Leurs and colleagues of EUROSTAR. "For this reason, vigilant surveillance remains indicated in all patients who undergo endovascular abdominal aortic aneurysm repair.”

The devices reviewed were the Stentor, previously manufactured by MinTec (La Ciotat, France), now a part of Boston Scientific, and the Vanguard, an early product of Boston Scientific (Natick, MA, USA).



Related Links:
Catharina Hospital
Boston Scientific