Non-stenting Treatment Strategy for Acute Myocardial Infarction With Non-severe Stenosis(EROSION IV)

Inclusion Criteria: 1. Male or female patients aged ≥18 years and ≤75 years; 2. Diagnosis of type 1 AMI, including STEMI (onset \<24 hours or 7-14 days) or NSTEMI; 3. After coronary angiography (CAG) ± thrombus aspiration, TIMI flow in the culprit vessel is restored to grade 3 and maintained for at least 5 minutes, with diameter stenosis (DS) \<70% at the culprit lesion (QCA); 4. Reference diameter of the culprit lesion \>2.5 mm and ≤4.0 mm; 5. Patients or a legally authorized representative must provide written Informed Consent prior to any study related procedure. Exclusion Criteria: 1.Clinical exclusion criteria: 1. Severe cardiac dysfunction (Killip/NYHA class ≥ 3) or LVEF \< 30%; 2. Cardiopulmonary resuscitation (CPR) performed at the onset of AMI; 3. Persistent hemodynamic or cardiac electrical instability after TIMI flow restoration; 4. Contraindication to antithrombotic drugs, or concurrent hemorrhagic diseases such as peptic ulcer or coagulation disorders; 5. Contraindication to contrast; 6. Severe renal dysfunction \[defined as eGFR ≤30 ml/min/1.73m² or Scr ≥2.0 mg/dL\] without regular dialysis (patients with chronic renal insufficiency on regular dialysis may be considered for enrollment); 7. Active liver disease, defined as known infectious, neoplastic, or metabolic liver lesions, with ALT and AST \>3× upper limit of normal (ULN); 8. Previous history of CABG or PCI for the culprit lesion; 9. Patients with other concurrent severe diseases and an expected life expectancy of \<1 year; 10. Pregnant or lactating women. Women of childbearing potential must use effective contraceptive measures during the study treatment period; 11. Inability to comply with the study protocol or other conditions deemed unsuitable for study participation by the investigator. 2.Imaging exclusion criteria: 1. Non-culprit lesion with DS ≥70% or planned revascularization; 2. Left main coronary artery lesion with DS ≥50%; 3. Culprit lesion is a true bifurcation lesion requiring a two-stent strategy; 4. Long lesion (planned stent length \>60 mm); 5. Culprit lesion with dissection, false lumen, or other conditions necessitating stent implantation; 6. Target lesion has undergone pre-treatment (such as balloon dilation, rotational atherectomy, etc.). 3.Functional sub study: 1. Individuals who are allergic to adenosine triphosphate (ATP) or any component in its preparations; 2. Second and third degree atrioventricular block, sick sinus syndrome (without artificial pacemaker protectors); 3. Patients with bronchial asthma.