Through randomization using a randomization table, patients are classified as either Treatment group in maximally dilated coronary artery administered with nitrate formulation or General treatment group without nitrate preparation (control group) to evaluate whether there is a difference in diameter of the treated Ultimaster® stent and to evaluate the stability and effectiveness after the procedure

INTERVENTION: Drug : Through randomization using a randomization table, subjects are selected as the control group, which is the treatment group for the maximally dilated coronary artery administered with oral or spray nitrate formulations prior to the procedure, or the standard treatment group, according to the registration order. CONDITION: Diseases of the circulatory system PRIMARY OUTCOME: Average diameter diameter of the inserted stent SECONDARY OUTCOME: 1‐year myocardial infarction rate 1‐year heart death rate 1‐year target vascular failure rate thrombosis INCLUSION CRITERIA: 1. Coronary Artery Disease 2. Vessle diameter 2.25 3.5mm, stenosis upper 50% 3. Those who voluntarily agreed in writing to participate in this clinical trial