Abstract 3666: Matrix Metalloproteinase-9 may be a New Biomarker for Coronary Plaque Rupture in Patients with Acute Myocardial Infarction
Background: Matrix Metalloproteinase-9 (MMP9) is closely linked to developing plaque rupture of coronary artery. We determined regional changes in MMP9 in culprit coronary artery and peripheral vein in patients with acute myocardial infarction (AMI) and angina pectoris (AP) to elucidate whether plasma MMP9 is useful for evaluating plaque rupture of culprit coronary artery.
Methods and Results: Seventy patients with AMI, 10 patients with unstable AP and 10 patients with stable AP were enrolled in the study. Cardiac catheterization and intravascular ultrasound (IVUS) were performed. Blood samples were collected from the ischemia-related coronary artery (CA) and the peripheral vein (PV) to measure MMP9, tissue inhibitors of metalloproteinase-1 (TIMP-1) and high-sensitivity-C-reactive protein (hs-CRP). Plasma MMP-9 levels in CA were 24.6 ng/ml in patients with AMI, a value significantly greater than the respective 8.8 ng/ml and 5.1 ng/ml in patients with unstable AP and AP (p<0.001). Plasma MMP-9 of 24.6 ng/ml in CA was greater than that of 12.0 ng/ml in PV (p<0.0001). In contrast, there was no difference in plasma TIMP-1 levels and hs-CRP levels between CA and PV. There was a positive correlation of plasma MMP9 between CA and PV (r=0.50, p<0.001). The procedure of IVUS confirmed the rupture of coronary plaque in 31 patients with AMI (47%). Plasma MMP-9 levels in CA were 32.3 ng/ml in the AMI patients with coronary plaque rupture, a value significantly greater than those of 18.4 ng/ml in patients without plaque rupture (P<0.0001). Plasma MMP-9 levels in PV were 15.5 ng/ml in the AMI patients with coronary plaque rupture, a value significantly greater than those of 9.2 ng/ml in patients without plaque rupture (P<0.001).
Conclusions: The present study may indicate that MMP9 in PV is a new biomarker for coronary plaque rupture in patients with AMI.