This study is to compare clinical outcomes between quantitative coronary angiography-guided anatomic complete revascularization and fractional flow reserve-guided physiologic complete revascularization in patients with significant coronary artery disease undergoing percutaneous coronary intervention with drug eluting stent

This is a prospective, multicenter center, open-label, randomized trial to compare QCA-guided versus FFR-guided CR strategies in patients with significant CAD who are undergoing PCI with DES. Patients with symptoms or evidence of myocardial ischemia are eligible for enrollment if there have stenotic lesions with a diameter stenosis of 50%-90% in major epicardial coronary arteries ≥ 2.25 mm in diameter by visual estimation, and CR is expected to be achievable by PCI. The detailed information for inclusion and exclusion criteria is described below in the session 4. Patients meeting inclusion criteria without any exclusion criteria will be randomized to either QCA-guided CR or FFR-guided CR group. In the QCA-guided CR group, PCI will be performed if there are lesions with diameter stenosis ≥ 50% by QCA during the index procedure (and, if necessary, planned staged procedure). In the FFR-guided CR group, FFR is measured for the target coronary lesions, and then PCI will be performed for the lesions with FFR ≤0.80. Post-PCI FFR measurement is strongly recommended. However, additional procedures are not recommended based on post-PCI FFR value because there is no consensus of the optimal cut-off value to define physiologic CR. In both QCA-guided and FFR-guided PCI groups, imaging guidance during PCI is left at the discretion of the operator. However, routine high pressure post-dilation with noncompliant balloons is recommended to achieve optimal stent expansion with minimal residual stenosis (diameter stenosis < 10% on visual estimation). Patients will be followed clinically at 1, 6, 12 months, and then upto 5 years after the index procedure

Inclusion Criteria:

• Men or women between the ages of 19and older
• Typical chest pain or objective evidence of myocardial ischemia suitable for PCI Significant lesions with a diameter stenosis of 50-90% in major epicardial coronary arteries ≥ 2.25 mm in diameter by visual estimation.
• The patient or guardian agrees to the study protocol and the schedule of clinical follow-up, and provides informed, written consent, as approved by the appropriate Institutional Review Board/Ethical Committee of the respective clinical site.

Exclusion Criteria:

• Coronary lesions resulting in the expected inability to perform FFR (ex, severe tortuosity or extreme angulation of the vessels)
• Chronic total occlusion
• Failed PCI of severe stenotic (diameter stenosis > 90%) or ACS culprit lesions
• Previous PCI within 6 months before the index procedure
• Previous coronary artery bypass graft surgery
• Cardiogenic shock or hemodynamic instability
• Left ventricular dysfunction (ejection fraction < 35%)
• Life expectancy < 1 years for any non-cardiac or cardiac causes
• Any surgery requiring general anesthesia or discontinuation of aspirin and/or an ADP antagonist is planned within 12 months after the procedure
• A diagnosis of cancer (other than superficial squamous or basal cell skin cancer) in the past 3 years or current treatment for the active cancer
• Patient's pregnant or breast-feeding or child-bearing potential.
• A known intolerance to antiplatelet agents (aspirin, clopidogrel, prasugrel or ticagrelor)
• Hypersensitivity or contraindication to DES material and its degradants and cobalt, chromium, nickel, platinum, tungsten, acrylic and fluoro polymers that cannot be adequately pre-medicated
• Any clinically significant abnormality identified at the screening visit, physical examination, laboratory tests, or electrocardiogram which, in the judgment of the investigator, would preclude safe completion of the study
• Unwillingness or inability to comply with the procedures described in this protocol