Objective To evaluate the effectiveness and safety of Ligustrazini Injection in post-treating acute ST elevation myocardial infarction（ STEMI）. Methods Randomly divided 100 cases of patients with STEMI and adopting percutaneous coronary intervention into control group and test group

with 50 cases each. The control group was given Tirofiban Hydrochloride Injection 10 μg / kg for intracoronary injection after balloon dilatation with continuous intravenous pump of 0. 2 mg / h for 48 hours after operation. The test group was given Tirofiban Hydrochloride Injection10 μg / kg for intracoronary injection after balloon dilatation. After this

20 mg ligustrazini injection was given for intracoronary injection. After the operation

on the basis of tirofiban treatment in the control group

intravenously given ligustrazine hydrochloride injection 80 mg / d for 7 days. Compared ST segment elevation range on electrocardiogram

creatine kinase（ CK）

creatine kinase MB（ CK-MB）

phospholipase A2

coronary corrected TIMI frame count（ CTFC）

left ventricular ejection fraction（ LV-EF） and function of platelet aggregation（ PAG%） in two groups before and after treatment

and observed adverse reactions. Results The total effective rate of the test group was93. 6%

remarkably higher than those of the control group of 83. 3%（ P = 0. 033）. The level of CTFC

PAG%

the range of ST segment elevation

CK

CK-MB

phospholipase A2 of two groups after treatment all remarkably decreased while that of LV-EF remarkably increased（ P < 0. 01）. The level of CTFC

PAG%

the range of ST segment elevation

CK-MB and phospholipase A2 of the experiment group were all remarkably lower than those of the control group（ P < 0. 05 or P < 0. 01）. Patients in both groups had no obvious adverse reactions. Conclusion Ligustrazini injection in post-treating STEMI had exact curative effects and could decrease myocardial damage with good safety.