This study is designed to evaluate the efficacy and safety of compound Danshen dropping pills (CDDP) in improving ventricular remodeling and cardiac function after acute anterior wall ST-Elevation myocardial infarction(STEMI). 268 patients with acute anterior wall STEMI after primary Percutaneous Coronary Intervention (pPCI) are randomly assigned 1:1 to CDDP group(n=134) and control group(n=134) with follow-up of 24 weeks. Both groups are treated with standard therapy of STEMI, with the CDDP group administrating 20 tablets of CDDP before pPCI and 10 tablets three times a day after pPCI and the control group treated with placebo at the same time. The primary endpoint is 24-week echocardiographic including left ventricle ejection fraction (LVEF) , left ventricular end-diastolic volume index (LVEDVI) and left ventricular end-systolic volume index (LVESVI).The secondary endpoint is the change in N terminal pro-B-type natriuretic peptide（NT-proBNP ）level, arrhythmia and cardiovascular events (death, cardiac arrest or cardiopulmonary resuscitation, hospitalization due to heart failure or angina pectoris).

Background: Progressive ventricular remodeling after acute anterior wall myocardial infarction（MI）is an important factor in the occurrence and death of heart failure. Angiotensin converting enzyme inhibitors and beta-blockers can ameliorate post-MI ventricular remodeling, but high-dose therapy can't be tolerable because of hemodynamic instability in the early stage of acute mycardial infarction（AMI）. It is known that traditional Chinese medicine, compound Danshen dropping pills (CDDP) exerts protective effect on microcirculatory disturbance caused by ischemia-reperfusion injury and improves energy metabolism after acute myocardial ischemia. Experimental studies have shown CDDP may attenuate ventricular remodeling after myocardial infarction.

Methods：This study is designed to evaluate the efficacy and safety of CDDP in improving ventricular remodeling and cardiac function after acute anterior wall ST-Elevation MI(STEMI). 268 patients with acute anterior wall STEMI after primary Percutaneous Coronary Intervention (pPCI) are randomly assigned 1:1 to CDDP group(n=134) and control group(n=134) with follow-up of 24 weeks. Both groups are treated with standard therapy of STEMI, with the CDDP group administrating 20 tablets of CDDP before pPCI and 10 tablets three times a day after pPCI and the control group treated with placebo at the same time. The primary endpoint is 24-week echocardiographic including left ventricle ejection fraction (LVEF) , left ventricular end-diastolic volume index (LVEDVI) and left ventricular end-systolic volume index (LVESVI).The secondary endpoint is the change in N terminal pro-B-type natriuretic peptide（NT-proBNP） level, arrhythmia and cardiovascular events (death, cardiac arrest or cardiopulmonary resuscitation, hospitalization due to heart failure or angina pectoris).

Discussion：This is the first prospective study that will demonstrate the impact of CDDP on ventricular remodeling and cardiac function in patients treated with pPCI for a first acute anterior wall STEMI .This study may provide novel insights of Traditional Chinese Medicine , CDDP to improve ventricular remodeling.

Inclusion Criteria:

1. Aged 18-75 years, gender unlimited;
2. According to the guidelines for diagnosis and treatment of acute ST segment elevation myocardial infarction (2019), patients with acute anterior ST segment elevation myocardial infarction were diagnosed;
3. Patients with primary acute myocardial infarction;
4. Patients who completed PCI reperfusion treatment within 12 hours after the onset of the disease;
5. Patients categorized as Classes I, II or III according to Killip classification on admission;
6. Subjects participated in the study voluntarily and signed informed consent.

Exclusion Criteria:

1. Patients with previous cardiac insufficiency caused by other diseases (valvular heart disease, congenital heart disease, pericardial disease, arrhythmia, other non cardiac causes);
2. The patients underwent coronary artery bypass graft（CABG） within 12 weeks;
3. Patients undergoing cardiac resynchronization;
4. Patients with left ventricular outflow tract obstruction;
5. Patients with myocarditis;
6. Patients with uncontrolled severe arrhythmia;
7. Patients with aortic aneurysm;
8. Patients with serious liver, kidney, blood system, mental disease or systemic disease;
9. Significant liver and kidney dysfunction (ALT > 2.0 times the upper limit of normal value; creatinine > 1.5 times the upper limit of normal value);
10. Patients with serum potassium > 5.5mmol/l;
11. Uncontrolled hypertension (higher than 180 / 110mmhg);
12. Pregnant or lactating women;
13. Patients allergic to compound Danshen Dropping Pills; 1
14. Patients participating in clinical studies of other drugs.