Beyond lipid-lowering effects, statins have favorable effects on platelets, endothelial function, plaque stability, and inflammation. These "pleiotropic" effects could contribute to microvascular function preservation during ischemia. Data are limited about the impact of previous treatment with statins on outcomes of patients with ST-elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (PCI). Accordingly, the aim was to evaluate the effect of previous statin treatment on clinical outcomes of such patients. A total of 950 consecutive patients with STEMI treated with primary PCI who were included in our primary PCI registry from January 2001 to July 2007 were studied. Excluded were patients with cardiogenic shock. Patients were allocated into 2 groups: those who received previous statin treatment (n=327) and those who did not (n=623). Patients who received previous statin treatment were older and more likely to be women; have diabetes, hypertension, hyperlipidemia, renal insufficiency, and anemia; or have had a previous myocardial infarction. Procedural characteristics were similar between the 2 groups. Despite the higher risk profile, patients who received previous statin treatment had a lower 30-day mortality rate (1.5% vs 3.8%; p=0.05). However, at 6 months, mortality differences were no longer evident and patients who received previous statin therapy had a higher rate of target-vessel revascularization (12.4% vs 7.6%; p=0.02). Multivariate analysis showed that previous statin treatment was associated with an odds ratio of 0.4 (95% confidence interval 0.13 to 0.96, p=0.045) for 30-day mortality. In conclusion, the present study suggested that previous therapy with statins in patients with STEMI treated using primary PCI may be associated with reduced short-term mortality.