Does the type of endograft affect AAA volume change after endovascular aneurysm repair?

PURPOSE: To compare thrombus volume changes in a longitudinal study over 2 years after endovascular aneurysm repair using the Ancure and Excluder endografts. METHODS: In 2 institutions, all consecutive patients treated with a bifurcated Ancure or Excluder endograft were included in this retrospective comparison of computed tomographic angiography (CTA) data recorded and stored to disk postoperatively and at the 12 (12M) and 24-month (24M) follow-up examinations. In one institution, among 45 Ancure endograft patients, 35 (group A) had the 3 requisite scans available. In the second institution, 23 (group B) of 36 patients with the Excluder endograft were eligible for analysis. The proportional volume change was calculated at 12M and 24M and compared to the postoperative CT data. More than 10% shrinkage was considered significant. RESULTS: In both groups, the median absolute volume changed significantly. In group A, significant shrinkage was found in 66% (23/35) at 12M and 74% (26/35) at 24M; in group B, 46% (10/23) had significant shrinkage at 12M as well as at 24M (p=0.027 for the difference between groups A and B at 24M). Statistical analysis of the proportional volume change showed a significant difference between the Ancure and the Excluder devices at 12M (p=0.009) and 24M (p=0.001). Multivariate analysis found aneurysm size (p