Clinical Research Directory

Inclusion Criteria: * Patients aged 40 years or older * Patients suspected of having chronic coronary syndrome who have undergone coronary angiography and confirmed stenotic lesions * Patients with lesions suitable for stent insertion who have 50% or more visually estimated stenosis in major coronary arteries with a diameter of 2.5 mm or greater observed on coronary angiography, and who satisfy one or more of the following conditions: 1. Patients with stenosis of 70% or more confirmed via Quantitative coronary angiography (50% or more for the left main coronary artery) 2. Minimum lumen area (MLA) ≤ 4 mm² or plaque burden \>70% on intravascular ultrasound (IVUS) 3. MLA \<3.5 mm² or area stenosis (AS) \>65% on Optical Coherence Tomography (OCT) 4. The corresponding stenosis on localizing stress imaging using SPECT or PET When there is a significant focal ischemic deficit in the coronary artery region of the lesion and the total perfusion deficit (TPD) is ≥10% 5. Pressure wire-based fractional flow reserve (FFR) ≤0.80 * Patients who can verbally confirm their understanding of invasive physiological or imaging evaluations and the benefits, harms, and alternative treatments of coronary angioplasty using drug-eluting stents, and for whom the patient or their legal representative can submit a written consent form. Additional Criteria for nested RCT Studies * When heart rate control is deemed therapeutically important due to an accompanying increase in heart rate at rest or during symptomatic episodes. * When the use of beta-blockers is deemed clinically advantageous due to a history of myocardial infarction. * When beta-blockers can help control blood pressure and symptoms in cases of concomitant hypertension. * When there is a clinical situation requiring associated tachyarrhythmia or heart rate control. * When beta-blockers are deemed more appropriate due to a history of contraindications, intolerance, or side effects of calcium channel blockers. Exclusion Criteria: * Patients with Left Ventricular Ejection Fraction (LVEF) less than 35% * Patients with cardiogenic shock * Patients with pulmonary edema or heart failure unresponsive to standard treatment * Patients with unstable angina whose symptoms persist despite maximal drug therapy * Patients with a history of ST-segment elevation myocardial infarction (STEMI), non-ST-segment elevation myocardial infarction (NSTEMI), or unstable angina within the last 6 months * Patients with active bleeding * Patients with major bleeding of the gastrointestinal or urinary system within the last 3 months * Patients with coagulation disorders prone to bleeding (including heparin-induced thrombocytopenia) * Patients with hypersensitivity to or contraindications to the following drugs: Heparin, Aspirin, Clopidogrel, Prasugrel, Contrast media (Patients sensitive to contrast media are not excluded if the condition can be effectively prevented through pretreatment with steroids or diphenhydramine (e.g., flare-ups). * Patients for whom percutaneous coronary intervention (PCI) is contraindicated * Patients who have already undergone coronary artery bypass grafting (CABG) * Patients with in-stent restenosis in the target lesion * Patients with chronic total occlusion (CTO) in major coronary arteries * Patients with lesions having an FFR of less than 0.64 * Patients with coronary arteries that are anatomically unsuitable for both PCI and CABG * Patients with non-ischemic dilated cardiomyopathy or hypertrophic cardiomyopathy * Patients with severe valvular disease or those judged by the investigator to be likely to require valve surgery or percutaneous valve replacement during the study period * Patients with non-cardiac diseases, etc., with a life expectancy of less than one year or expected to have low treatment adherence (at the investigator's judgment) * Pregnant or breastfeeding patients * Other patients deemed by the investigator to be unsuitable for participation in the clinical trial Additional Criteria for nested RCT Studies * Significant bradycardia at rest, second-degree or higher atrioventricular block, or significant conduction disturbance * Bronchial asthma or clinically significant bronchospasmodic disease * Symptomatic hypotension * Variant angina as a main presentation * Other cases where the supervising investigator deems the use of beta-blockers medically inappropriate