Revascularization Versus Medical Treatment in Patients With Ischemic Left Ventricular Dysfunction

Inclusion Criteria: * Subject must be at least 19 years of age * Patients with stage C heart failure and left ventricular ejection fraction\<40% * Patients with significant coronary artery stenosis (diameter stenosis\>50% with proven inducible myocardial ischemia by invasive physiologic assessment) * Coronary artery disease is amenable for percutaneous coronary intervention (PCI) * Subject is able to verbally confirm understandings of risks, benefits and treatment alternatives of receiving invasive approach and he/she or his/her legally authorized representative provides written informed consent prior to any study related procedure. Exclusion Criteria: * Myocardial infarction by universal definition within 4 weeks of randomization * Non-viable myocardium in myocardial viability test (cardiac magnetic resonance, dobutamine-stress echocardiography, delayed single-photon emission computerized tomography, or aneurysmal change in echocardiography) * Target lesions not amenable for PCI by operators' decision * Patients who need left ventricular assisted device (LVAD) or heart transplantation at the time of randomization * Intolerance to Aspirin, Clopidogrel, Prasugrel, Ticagrelor, Heparin, or Everolimus * Known true anaphylaxis to contrast medium (not allergic reaction but anaphylactic shock) * Pregnancy or breast feeding * Non-cardiac co-morbid conditions are present with life expectancy \<2 year or that may result in protocol non-compliance (per site investigator's medical judgment) * Unwillingness or inability to comply with the procedures described in this protocol.