Early inflammatory response after elective abdominal aortic aneurysm repair: a comparison between endovascular procedure and conventional surgery.

OBJECTIVE

To determine the nature of and to compare the inflammatory responses induced by (1) endovascular and (2) conventional abdominal aortic aneurysm (AAA) repair.

MATERIAL AND METHODS

Twelve consecutive patients undergoing elective infrarenal AAA repair were prospectively studied. Seven patients were selected for endovascular procedures (the EAAA group); five patients underwent open surgery (the OAAA group). Three control patients undergoing carotid thromboendarterectomy were also included. Serial peripheral venous blood samples were collected preoperatively, immediately after declamping or placement of the endograft, and at hours 1, 3, 6, 12, 24, 48, and 72. Acute phase response expression of peripheral T lymphocyte and monocyte activation markers and adhesion molecules (flow cytometry), soluble levels of cell adhesion molecules (enzyme-linked immunosorbent assay), cytokine (tumor necrosis factor alpha, interleukin-6, and interleukin-8) release (enzyme-linked immunosorbent assay), and liberation of complement products (nephelometry) were measured.

RESULTS

Regarding acute phase response, the EAAA and OAAA groups showed significant increases in C-reactive protein (P <.001 and P =.001), body temperature (P =.035 and P =.048), and leukocyte count (P <.001 and P <.001). Similar time course patterns were observed with respect to body temperature (P =.372). Statistically significant different patterns were demonstrated for C-reactive protein (P =.032) and leukocyte count (P =.002). Regarding leukocyte activation, a significant upregulation of peripheral T lymphocyte CD38 expression was observed in the OAAA group only (P =.001). Analysis of markers such as CD69, CD40L, CD25, and CD54 revealed no perioperative fluctuations in any group. Regarding circulating cell adhesion molecules, the EAAA and OAAA groups displayed significant increases in soluble intercellular adhesion molecule-1 (P =.003 and P =.001); there was no intergroup difference (P =.193). All groups demonstrated high soluble von Willebrand factor levels (P =.018, P =. 007, and P =.027), there being no differences in the patterns (P =. 772). Otherwise, soluble vascular cell adhesion molecule-1, soluble E-selectin, and soluble P-selectin did not appear to vary in any group. Regarding cytokine release, although a tendency toward high tumor necrosis factor alpha and interleukin-8 levels was noticed in the EAAA group, global time course effects failed to reach statistical significance (P =.543 and P =.080). In contrast, interleukin-6 showed elevations in all groups (P =.058, P <.001, and P =.004). Time course patterns did not differ between the EAAA and OAAA groups (P =.840). Regarding complement activation, the C3d/C3 ratio disclosed significant postoperative elevations in the EAAA and OAAA groups (P =.013 and P =.009). This complement product release was reduced in the EAAA group (P <.001).

CONCLUSIONS

The current study indicated that both endovascular and coventional AAA repair induced significant inflammatory responses. Our findings showed that there were no large differences between the procedures with respect to circulating cell adhesion molecule and cytokine release. Moreover, the endoluminal approach produced a limited response in terms of acute phase reaction, T lymphocyte activation, and complement product liberation. This might support the concept that endovascular AAA repair represents an attractive alternative to open surgery. Given the relatively small sample size, further larger studies are required for confirmation of our observations.