Plasma matrix metalloproteinase levels do not predict tissue levels in abdominal aortic aneurysms suitable for elective repair.

The role of matrix metalloproteinases (MMPs) in abdominal aortic aneurysm (AAA) pathogenesis is well described. However, a clear role for the MMPs in disease prediction has not been established. The aim of this study was to determine if circulating levels of MMPs correlated with AAA diameter and with MMP concentrations within the aneurysm wall. Preoperative plasma samples and intraoperative infrarenal AAA sac biopsies were taken in a standard fashion from 31 patients undergoing elective repair.The concentrations of MMP-1, MMP-2, MMP-3, MMP-9, tissue inhibitor of matrix metalloproteinase (TIMP)-1, and TIMP-2 were quantified in plasma and aneurysm wall homogenates using enzyme-linked immunosorbent assay. Comparison used the Spearman correlation. There were no correlations between the paired plasma and aneurysm wall concentrations for any MMP or TIMP. Correlation between MMP-9 levels in the aneurysm wall and aneurysm diameter was negative (r = -.42, p = .019). Other correlations between plasma and tissue levels with aneurysm diameter were nonsignificant.