The multicenter experience with a third-generation endovascular device for abdominal aortic aneurysm repair. A report...

The purpose of this study was to evaluate the effect of the preoperative diameter of abdominal aortic aneurysms (AAA) upon the midterm outcome obtained by endovascular AAA repair, using a third-generation endovascular device, the Excluder bifurcated endoprosthesis (W. L. Gore & Associates, Inc. Sunnyvale, CA, USA).

The data of 676 patients, who had undergone endovascular aneurysm repair (EVAR) were analysed. Patients were enrolled over a 6-year period to April 2004 in the EUROSTAR database. Outcomes were compared between 2 groups defined by the preoperative diameter of the aneurysm: group A (n=300), smaller than 5.5 cm; group B (n=376), 5.5 cm or larger. Patient characteristics, details of aorto-iliac anatomy, operative procedure and postoperative complications in the 2 patient groups were compared. Outcome events included aneurysm-related death, overall death, conversion, and late rupture of the aneurysm. Life table analyses and log rank tests were used to compare outcome in the study groups. Multivariate Cox models were used to determine whether baseline and follow-up variables were independently associated with adverse outcomes.

Patients in group B were significantly older than patients in group A (73 years vs 71 years respectively; p=0.006), and more frequently were at higher operative risk (ASA-classification >3; 44% vs 59%; p<0.0001). Anatomic differences included a higher incidence of aorto-iliac angulation, a wider and shorter infrarenal neck in group B. Risk factors that were more frequently observed in group B included hypertension, carotid disease and pulmonary disorders. Additional operative events including device migration occurred more frequently in group B (0% vs 2%; p=0.03). Device-related (type I and III combined) endoleaks were more frequently observed at completion arteriography in group B compared to group A (2% vs 4%; p=n.s.). Thirty-day mortality was comparable between the 2 study groups. However, the overall death rate after 3 years of follow-up was significantly higher in patients with larger aneurysms, group B (4% vs 14%; p=0.0025). Similarly, aneurysm-related death was significantly higher in group B (after 3 years 0.3% vs 3%; p=0.02). Aneurysm growth after EVAR was modest low in both study groups (after 2 years 6% vs 8%; non-significant). There was no correlation between growth of the sac and aneurysm-related death.

The midterm outcome after endovascular repair by Excluder devices was satisfactory in patients with small and large AAAs. A higher rate in all-cause deaths and aneurysm-related deaths in patients with larger aneurysms was observed. Post-EVAR aneurysm growth was observed in a small percentage of patients but this did not contribute to aneurysm-related death.