MMP9 and aneurysm: Ikonomidis et al. evaluated the implications of multiple MMPs (MMP-1, MMP-2, MMP-3, MMP-7, MMP-8, MMP-9, MMP-12, MMP-13, MMP-14 and MMP-15) and brought into light the paradoxical decrease in MMP-3 and MMP-14 in association with the medium-sized aneurysm group and BAV as opposed to the small or large aneurysm group.