The aim of this study is to evaluate the efficacy of alirocumab for in-stent neoatherosclerosis by using optical coherence tomography, in comparison with standard statin therapy.

The investigators investigate to evaluate the efficacy of alirocumab for in-stent neoatherosclerosis. The investigators enrolled the patient who performed drug eluting stent implantation and detected in-stent neoatherosclerosis by follow up optical coherence tomography, and categorized into two group; the patients with alirocumab and rosuvastatin the investigatorsre categorized alirocumab therapy group, and the patients with rosuvastatin alone were categorized standard statin therapy group.

The investigators compare these two group for outcomes.

Inclusion Criteria:

1. The age at the time of consent acquisition is 20 years old or over.
2. OCT Images that can be analyzed are obtained, and neoatherosclerosis existed in drug eluting stent
3. lipid lowering therapy with rosuvastatin 10 mg or rosuvastatin 10 mg and aliclumab is performed.
4. Baseline OCT was scheduled to be revisited within 6 to 12 months, or already performed.
5. Document consent has been obtained from the subject person to this research.

Exclusion Criteria:

1. Patients who have received treatment with PCSK 9 inhibitor in the past
2. Patients whose treatment was interrupted before follow-up catheterization during the observation period
3. Patients underwent LDL apheresis.
4. In the case that the researchers judges it as inappropriate as the object of this research.

Patients with stent implantation who were performed coronary angiography and optical coherence tomography (OCT) follow-up of the coronary arteries were candidate.

These patients were implanted drug elutingstent including sirolimus-eluting stents (Cypher, Cordis, Miami Lakes, FL, USA), paclitaxel-eluting stents (Taxus, Boston Scientific, Natick, MA, USA), or everolimus-eluting stents (XIENCE V, Abbott Vascular, Santa Clara, CA, USA). The investigators assessed their OCT examination at the follow-up OCT time and patients who were detected NA on OCT findings were eligible for the presence study.