Background: Matrix metalloproteinase (MMP) may contribute to myocardial remodeling after myocardial infarction. The goal of this study was to characterize the effects of pravastatin on circulating levels of MMP and on left ventricular dilatation after acute myocardial infarction (AMI). Methods: Thirty-four consecutive patients with successful reperfusion following AMI were assigned to either pravastatin group (group P, n=12) or non-pravastatin group (group NP, n=22). Serum MMP-2 and tissue inhibitor of MMP (TIMP)-2 were measured immediately after reperfusion, on days 2, 3, 7, 30, and at 6 months after MI. Left ventriculography was performed after reperfusion and at 4 weeks and 6 months. Results: MMP-2 levels were higher in patients with MI than control on days 1, 30, and at 6 months. Left ventricular end-diastolic volume index (LVEDVI) at 6 months correlated with MMP-2 levels on day 30 (r=0.47,p<0.01) and at 6 months (r=0.56,p<0.001). MMP-2 levels at 6 months were significantly lower in group P than group NP. Further, LVEDVI at 6 months tended to be smaller and Delta LVEDVI was significantly smaller in group P when compared with group NP. Conclusion: Serum MMP-2 varied in a time-dependent manner following AMI and correlated with late changes in LVEDVI. Serum MMP-2 levels were significantly lower in treatment group than in non-treatment group and Delta LVEDVI was significantly smaller in treatment group after long-term pravastatin administration. Use of statins in AMI patients may provide beneficial effects in terms of preventing heart failure over and above its lipid-lowering effects. (c) 2005 Elsevier Ireland Ltd. All rights reserved.