a prospective, single center, observational clinical trail. Aim to to compare the efficacy and safety of the Bioabsorbable scaffold (BRS) Neovas BRS and Drug-coating balloon (DCB) in the treatment of STEMI patients with coronary artery disease and to further evaluate the safety and effectiveness of the two new interventional methods in STEMI intervention, so as to better guide clinical practice.

1. To study the advantages and disadvantages of Neovas BRS and DCB in interventional treatment of de novo lesions in STEMI patients, in order to better guide the clinical.
2. To explore the safety of Neovas BRS in interventional treatment of ide novo lesions in STEMI patients.
3. To explore the safety of DCB in interventional treatment of de novo lesions in STEMI patients.

Inclusion Criteria:

1) Age > 18 years old (2) STEMI patients suitable for PPCI operation. Chest pain for more than 20 minutes; At least 2 leads ST-T segment elevation > 1 mm, or new LBBB, or myocardial infarction confirmed by echocardiography; It is expected that the reperfusion treatment can be successfully implemented within 12 hours after the occurrence of acute myocardial infarction.

(3) Target vessels are suitable for PPCI and Single vessel disease (non culprit vessel stenosis < 50%). It is a primary coronary lesion; Reference vessel diameter > 2.5mm and < 4mm, lesion length < 20mm; There is no obvious calcification at the lesion site; After thrombus aspiration or pre dilation balloon pretreatment, the residual stenosis < 30% has no blood flow restrictive dissection.

(4) Patients refused to accept drug-eluting stent implantation, voluntarily participated and signed informed consent, accepted and was willing to cooperate with follow-up, and was willing to cooperate with standard secondary prevention and treatment of coronary heart disease.

Exclusion Criteria:

The age is less than 18 years old; Previous history of myocardial infarction or post coronary stent operation; Left main disease; It is known that it is contraindications or resistance to the following drugs: bevaludine, low molecular heparin, common heparin, aspirin, clopidogrel / tegrelol; Participate in other clinical studies and interfere with the study; It is uncertain whether there is any neurological injury: for example, after resuscitation; It needs tracheal intubation / artificial ventilation; There was cardiogenic shock before grouping; It is known that there are intracranial diseases: occupying position, aneurysm, arteriovenous malformation, hemorrhagic cerebrovascular accident, ischemic cerebrovascular accident; Internal bleeding such as gastrointestinal bleeding before selection; It is planned to perform major surgical treatment within 6 weeks; Serious infectious disease, malignant tumor disease, serious blood disease and autoimmune disease; in recent March, there has been a history of large-dose use of immunosuppressant; Non coronary vasculitis and thrombotic diseases (vasculitis, aortic dissection, abdominal aneurysm); Serious mental illness patients; The life expectancy is less than 1 year; No consent to participate in the study.

STEMI patients undergoing PPCI