A Study to Evaluate the Impact of Pre-procedural Intracoronary Nicorandil Injection to PREVENT ReductioN of DecREased TIMI FLOW in Patients Who Undergoing Percutaneous Coronary Intervention for the Coronary Artery Disease

Inclusion Criteria: 1. Over 19 years old 2. Patients who agree to the study plan and clinical follow-up plan, voluntarily decide to participate in this study, and consent in writing to the consent to use information 3. Patients who underwent NIRS-IVUS guided coronary stent surgery for coronary artery disease Exclusion Criteria: 1. Patients with TIMI ≤ 2 before coronary intervention 2. Subjects with known hypersensitivity or contraindications to the following drugs or substances: heparin, aspirin, clopidogrel, ticagrelor, prasugrel, rosuvastatin, ezetimibe, evolocumab, lansoprazole, cobalt chromium, stainless steel nickel And contrast agents (however, even a subject who is hypersensitive to contrast agents can register if they can be controlled by steroids and pheniramine, except for known anaphylaxis.) 3. Pregnant women, lactating women, or women of childbearing age who plan to become pregnant during this study 4. Subjects who plan to have surgery to stop antiplatelet drugs within 6 months from registration 5. Those whose surviving life is expected to be less than 1 year 6. Subjects who visited the hospital due to cardiogenic shock and are predicted to have low survival probability based on medical judgment