Comments regarding ‘Plasma Levels of Matrix Metalloproteinase-9: A Possible Diagnostic Marker of Successful Endovascular Aneurysm Repair’

Abstract

1078-5884/$ e see front matter 2011 European So doi:10.1016/j.ejvs.2011.11.004 A more rational approach to the surveillance of patients with endovascular aneurysm repair (EVAR) is urgently needed. Recent publications have questioned the benefit of surveillance and demonstrated that significant heterogeneity of surveillance schedules exists among vascular units.1,2 Current imaging modalities reliably identify endoleak and other stent-graft related complications but are costly and some are potentially harmful. A blood test which might predict complications or the need for secondary interventions would be attractive. Endoleak is an important but not the sole cause of late failure of aortic stent-grafts. Iliac limb occlusion and stent-graft migration are important predictors of secondary intervention. Many endoleaks are entirely benign and the detection of these benign (most frequently type 2) endoleaks will not improve outcomes. Previous studies have suggested that plasma levels of MMPmay identify endoleak.3,4 This preliminary report is encouraging and builds on these studies but does not tell us whether this approach might be able to discriminate benign from dangerous endoleaks nor whether MMP levels might change in individual patients subsequent to the development or successful treatment of endoleak.5 Larger longitudinal studies, which the authors report to be already underway, are required to confirm these findings and establish whether other demographic factors or complications might impact upon the levels of various MMPs.