Abstract： Background The clinical outcome of percutaneous coronary intervention (PCI) is poorer in women than that in men.This study aimed at comparing the impact of gender difference on the strategy of primary PCI in patients with acute ST-segment elevation myocardial infarction (STEMI).Methods Two hundred and fifty-nine patients with STEMI who underwent primary PCI within 12 hours of symptom onset were enrolled.The male group consisted of 143 men aged >55 years,and a female group included 116 women without age limitation.Procedural success was defined as residual stenosis <20% with thrombolysis in myocardial infarction flow grade>2 and without death,emergency bypass surgery or disabling cerebral events during the hospitalization.The rate of major adverse cardiac events (MACE),including death,nonfatal myocardial infarction and target vessel revascularization during follow-up,was recorded.Results Female patients were more hypertensive and diabetic and with fewer cigarette smokers than male counterparts.The prevalence of angiographic 3-vessel disease was higher in the female group,but the procedural success rate was comparable between the two groups (94.4% vs 92.2%).The occurrence rate of MACE did not differ during the hospitalization (4.2% vs 6.0%,P=0.50),but was significantly higher in the female group during follow-up (mean (16.0±11.2) months) than that in the male group (5.4% vs 0.7%,P=0.02).Conclusion Despite a similar success rate of primary PCI and in-hospital outcomes in both genders,female patients with acute STEMI still have a worse prognosis during the long-term follow-up.