IVUS-Guided vs Angiography-Guided PCI in Acute Coronary Syndrome

Inclusion Criteria: 1. Patients 19 years of age or older 2. Patients with unstable angina pectoris, and acute MI including NSTEMI or STEMI. 3. Coronary artery disease defined as \>70% stenosis (reference vessel diameter 2.5 - 5.0 mm based on operator assessment) with identifiable culprit lesion indicated stent implantation 4. All lesions must be suitable for treatment with the Synergy stent system, or other Synergy platform iteration 5. The patient or guardian agrees to the study protocol and the schedule of clinical and angiographic follow-up, and provides informed, written consent, as approved by the appropriate Institutional Review Board/Ethical Committee of the respective clinical site. Exclusion Criteria: 1. Age \>90 years 2. Subject has known hypersensitivity or contraindication to device material and its degradants (everolimus, poly(L-lactide), poly(DL-lactide), lactide, lactic acid) and cobalt, chromium, nickel, platinum, tungsten, acrylic, and fluoro polymers that cannot be adequately premedicated. 3. Absolute contraindications or allergy that cannot be pre-medicated, to iodinated contrast or to antiplatelet drugs, including both aspirin and P2Y12 inhibitors 4. An elective surgical procedure is planned that would necessitate interruption of antiplatelet drugs within 6 m after the procedure. 5. Cardiogenic shock 6. Restenotic lesions 7. Compromised left ventricular dysfunction (LVEF \<30%) 8. At the time of screening, the subject has a malignancy that is not in remission 9. Non-cardiac co-morbidities with a life expectancy less than 1 year 10. Patients who are actively participating in another drug or device investigational study, which have not completed the primary endpoint follow-up period. 11. Subject belongs to a vulnerable population (per investigator's judgment) or subject unable to read or write 12. Concern for inability of the patient to comply with study procedures and/or follow-up (e.g., alcohol or drug abuse) 13. Pregnancy