MMP9 and atherosclerosis: Further, increased levels of MMP-9 promote plaque development in the vasculature9, and elevated levels of MMP-9 has been found in patients with hypertension than normotensive controls (2.31 ± 0.2 vs 1.94 ± 0.3)10 and correlated with higher femoral atherosclerosis (r = 0.16; P < 0.01)11.