ABSTRACT
Endovascular repair of AAA's using stent grafts is considered to be a minimally invasive procedure. However, in some cases deleterious inflammatory reactions, e.g., flu-like postinterventional symptoms are observed. A few patients even develop a fatal "postimplantation syndrome". It is not clear whether these postoperative complications result from a) the inflammatory and immune response to the inserted graft material, b) alterations of the vascular endothelium during the implantation procedure, c) residual thrombotic material, or d) a combination of all these causes. This clinical trial aimed to prospectively investigate the association between inflammatory mediators like interleukin-1 receptor antagonist (IL-1RA), IL-6, and HLA-DR expression on monocytes and clinical outcome in patients after repair of abdominal aortic aneurysms (AAA). Fifteen patients treated with endovascular stent grafts for abdominal aortic aneurysm (AAA-E) were compared with 15 selected control patients who underwent a conventional surgical procedure (AAA-K) during the same period. Prior to intervention, there were no significant differences in marker levels. One hour postoperatively, IL-6 (421 pg/ml vs. 21 pg/ml) and IL-1RA (10,061 pg/ml versus 407 pg/ml) were significantly increased in the AAA-K-group, whereas in AAA-E patients, these parameters increased more gradually during the first postoperative day and did not reach the same level as in the control group. There was only a slight reduction of HLA-DR expression in both groups compared with baseline and no signs indicating a postimplantation syndrome were found. No excessive inflammatory response or complicated final outcome were observed. It is unclear if this can be explained by the prophylactic use of indometacin.