DES are preferred over BMS for most patients, however prolonged dual antiplatelet therapy is required for patients treated with DES for prevention of late or very late stent thrombosis. which increases a risk of major bleeding. BioFreedom is a Biolimus A9-coated stent that consists of a stainless steel stent platform with a textured abluminal surface without use of any polymer in the coating. Biolimus A9 rapid release and polymer-free property may give BioFreedom the advantages of both DES and BMS that may require less duration of DAPT. BioMatrix Flex, Biolimus-eluting stent with biodegradable polymer, also demonstrated safety and efficacy. We will compare these two difference types of Biolimus A9-eluting stents with different duration of DAPT. With proven adequate and safe duration, we will compare between one versus more than six months of dual antiplatelet therapy after Biolimus A9-eluting stents implantation using different properties of BioFreedom and BioMatrix Flex.

Inclusion Criteria:

• Patients ≥ 19 years old
• Patients with ischemic heart disease who are considered for coronary revascularization with PCI
• Significant coronary de novo lesion

Exclusion Criteria:

• Acute myocardial infarction
• Complex lesion morphologies such as aorta-ostial, unprotected left main, chronic total occlusion, graft, thrombosis, heavy calcified (definite calcified lesions on angiogram) or extremely tortuous lesion
• Need to use of dual antiplatelet therapy more than 1 month because of other medical conditions
• Cardiogenic shock or experience of cardiopulmonary resuscitation
• Contraindication or hypersensitivity to Biolimus A9, stainless steel, heparin, antiplatelet agents or contrast media
• History of documented prior cerebrovascular attack within 6 months
• Treated with any stent within 3 months
• Reference vessel diameter <2.25 mm or >4.0 mm
• Pregnant women or women with potential childbearing
• Inability to follow the patient over the period of 1 year after enrollment, as assessed by the investigator
• Inability to understand or read the informed content