Serum matrix metalloproteinase-9 concentration in angiographically assessed coronary artery disease.

Expression of several matrix metalloproteinases (MMPs) in atherosclerotic plaques has been well documented, and there are findings to indicate that arterial inflammation is reflected in increased serum concentration of matrix metalloproteinase-9 (MMP-9). In coronary atherosclerosis, there is enhanced expression of this MMP, which may be predictive of the severity of the disease. We determined the concentrations of serum MMP-9 in 61 patients (47 males, 14 females) who had >50% obstruction in one or more coronary arteries as assessed by coronary angiography before bypass surgery.