Background Prognosis of patients with acute ST-elevation myocardial infarction (STEMI) and renal dysfunction (RD) who received primary percutaneous coronary intervention (PCI) has not been fully investigated in the drug-eluting stent (DES) era.This study aimed to evaluate the impact of admission serum creatinine level on short-term outcomes in patients with acute STEMI undergoing DES-based primary PCI.Methods Primary PCI with DES implantation was attempted in 619 consecutive STEMI patients within 12 hours of symptom onset.Among them,86 patients had a serum creatinine level >115 μmol/L on admission (RD group),and the remaining 533 patients had normal renal function (non-RD group).The primary endpoint was 30-day major adverse cardiac events (MACE,including death,non-fatal reinfarction,and target vessel revascularization),and the secondary endpoint was subacute stent thrombosis.Results Patients in the RD group were older than those in the non-RD group.There are more female patients in the RD group and they had a history of hypertension,myocardial infarction and revascularization.The occurrence rates of Killip class ≥2 (29.1% vs 18.6%,P=0.02) and multi-vessel (62.8% vs 44.5%,P=0.001) and triple vessel disease (32.6% vs 18.2%,P=0.002),in-hospital mortality (9.3% vs 3.8%,P=0.03),and MACE rate during hospitalization (17.4% vs 7.7%,P=0.006) were higher in the RD group than those in the non-RD group.At a 30-day clinical follow-up,the MACE-free survival rate was significantly reduced in the RD group (76.7% vs 89.9%,P=0.0003).Angiographic stent thrombosis occurred in 3 (3.5%) and 7 (1.3%) of patients in the RD group and non-RD group,respectively (P=0.15).Multivariate analysis revealed that the serum creatinine level≥115 μmol/L on admission was an independent predictor for MACE rate at a 30-day follow-up (Hazard ratio (HR) 3.31,95% CI 1.19-9.18,P<0.001).Conclusion Despite similar prevalence of stent thrombosis at a 30-day clinical follow-up,the short-term prognosis of STEMI patients with elevated serum creatinine on admission undergoing DES-based primary PCI remains unfavorable.