Is endovascular treatment of abdominal aortic aneurysms less invasive regarding the biological responses?

To compare the biological responses following an endoluminal repair and a conventional open repair of abdominal aortic aneurysm (AAA), 14 patients who underwent an endoluminal repair (endograft group) and 26 who underwent an open repair (open group) were investigated. As markers of biological responses, interleukin-6 (IL-6) and -8 (IL-8), granulocyte elastase (GEL), white blood cell count (WBC), and serum C-reactive protein (CRP) were all measured preoperatively as well as on postoperative days (POD) 1, 3, and 6. In addition, the blood loss, duration of surgery, initial oral intake the day after surgery, and length of hospital stay were compared between both groups. The plasma levels of IL-6, GEL, CRP, and WBC were higher in the endograft group than in the open group, while the CRP, WBC, and GEL levels all peaked on POD 3. The plasma level of IL-6 remained high in the endograft group, compared with that in the open group throughout the study period. Conversely, blood loss, initial oral intake the day after surgery, and the length of hospital stay were all significantly greater in the open group than in the endograft group, although there was no significant difference in the duration of surgery between the two groups. These findings indicate that although the endoluminal repair of AAA is supposed to be less invasive, the biological responses tend to be greater because of the manipulation related to the insertion of the stent graft.