Optical coherence tomography (OCT) after the stent procedure to improve the adhesion and expansion, or incomplete uncovered struts attached to the main track. OCT in clinical areas by improving the parameters of the best stent will be useful. However, for better results for optical coherence tomography in percutaneous interventions have little useful data on the role. Randomized controlled study of the traditional percutaneous coronary intervention and intervention using optical coherence tomography.

Inclusion Criteria:

• Single lesion in a Single vessel
• Reference vessel diameter 2.5 - 3.5 mm
• Lesion length ≤ 34 mm and ≤ 34 mm stent length
• Stable angina requiring revascularization, patients with unstable angina
• The patient has no difficulty to enforce the follow-up angiography
• Patient is ≥ 20 years old

Exclusion Criteria:

• Lesions with graft vessel, thrombosis, restenosis, and bifurcation requiring 2 stents
• Reference vessel diameter < 2.5 mm or > 4.0mm
• Contraindication to anti-platelet agents
• Treated with any DES within 3 months at other vessel
• Creatinine level ≥ 2.0 mg/dL or ESRD
• Severe hepatic dysfunction (3 times normal reference values)
• Patients with LVEF < 30%
• Life expectancy 1 year
• Lesions with CTO or left main
• Target vessel of ST-elevation MI
• Lesions requiring overlapped stenting or more than 2 DES in each vessel
• Heavy calcified lesions (definite calcified lesions on angiogram)
• Far distal or tortuous lesions having difficulties in OCT evaluation or follow-up OCT
• Pregnant women or women with potential childbearing