UC-MSC Transplantation for Left Ventricular Dysfunction After AMI

Inclusion Criteria: * Patients with acute extensive anterior myocardial infarction were successfully treated with emergency interventional therapy within 12 hours after onset. LVEF was less than 0.35 by echocardiography 30 days after operation, scar area was more than 25% by MRI, and cardiac function was NYHA III-IV grade. * Fully inform the purpose, method and possible side effects of the test, agree to the test, and sign an informed consent form; * Good compliance, willing to take drugs and follow up according to the requirements of the plan; * Life expectancy exceeds one year. Exclusion Criteria: * Those who cannot tolerate cell therapy; * Patients with severe hepatic and renal insufficiency (ALT\>1.5 times the upper limit of normal value, Cr \>1.5 times the upper limit of normal value); * Patients with malignant tumors or extremely weak patients; * Patients with severe infection; * Patients who are expected to have the second coronary intervention or bypass grafting within 3 months; * Patients with other serious systemic diseases and organ dysfunction; * Patients with cardiogenic shock; * Patients with hemorrhagic diseases; * Researchers believe that anyone who is not suitable for inclusion