TIMP-1 is a preferential inhibitor for MMP-9, and an elevated MMP-9/TIMP-1 ratio has been reported in the tissue of the aortic wall from patients with thoracic aortic aneurysms.[11–13,16] Upregulation of inflammation in the aortic wall of Marfan mice with concomitant increase in TIMP-1 in the aortic wall has also been recently reported.[17] Our results showed TIMP-1 but not MMP-9 to be associated with aortic dimensions which may be attributable to inflammatory contribution rather than aortic wall remodeling. This evidence concerns the gene MMP9 and thoracic aortic aneurysm.