Inclusion Criteria:  Clinical diagnosis of acute coronary syndrome The degree of coronary artery stenosis is greater than 90% The degree of coronary artery stenosis is greater than 75% and there is evidence of ischemia  Exclusion Criteria:  Patients who did not receive stents for the first time Patients who had undergone coronary artery bypass grafting Patients with stent implantation due to stent stenosis Patients who had stents implanted for chronic complete coronary artery occlusion Patients with malignant tumors Patients with autoimmune diseases Patients with severe hepatic and renal insufficiency Patients with cardiomyopathy Patients with congenital heart disease Patients with valvular disease Patients present with acute stress events