Acute myocardial infarction is one of the leading causes of death in elderly patients, and the importance of lipid-lowering therapy as a secondary prevention strategy to reduce cardiovascular events is emphasized. The European Society of Cardiology (ESC) and American Heart Association (AHA) guidelines recommend lowering low-density lipoprotein-cholesterol (LDL-C) below 55 mg/dL or by at least 50% from baseline as a treatment goal and recommend high-intensity statin therapy (Atorvastatin 40-80 mg, Rosuvastatin 20 mg). Statins have been shown to reduce cardiovascular risk in elderly patients as well. However, these patients exhibit a higher rate of statin intolerance due to side effects associated with high-intensity statins, such as myalgia, hepatotoxicity, cognitive decline, and increased risk of diabetes. Consequently, dose reduction or discontinuation is required more frequently compared to younger patients. Therefore, establishing an appropriate lipid-lowering strategy for elderly patients is necessary, considering not only efficacy but also drug tolerability. Consequently, in elderly patients, reducing the statin intensity from the outset and considering combination therapy with drugs having different mechanisms of action, such as ezetimibe, may be warranted. Pitavastatin is classified as a moderate-intensity statin. Previous studies have confirmed that Pitavastatin demonstrates non-inferior efficacy compared to Rosuvastatin and Atorvastatin. Several observational studies report that Pitavastatin has fewer drug interactions than other statins and lower rates of diabetes onset and elevated liver enzymes. Therefore, Pitavastatin may be an appropriate choice for moderate-intensity statin therapy in elderly patients. Thus, this study aims to evaluate whether combination therapy with Pitavastatin and Ezetimibe (Livalozet 4/10mg) after coronary intervention in patients aged 75 years or older with coronary artery disease is non-inferior to high-intensity statin therapy (Atorvastatin 40-80 mg or Rosuvastatin 20 mg). If this study demonstrates that moderate-intensity statin therapy combined with ezetimibe is non-inferior to high-intensity statin therapy while also having fewer adverse effects, it could provide evidence for an effective and safe cholesterol treatment option for elderly patients.

Inclusion Criteria

• Age 75 years or older
• Patients diagnosed with stable coronary artery disease or acute coronary syndrome and requiring coronary artery intervention due to coronary artery stenosis
• Patients with primary hypercholesterolemia and mixed dyslipidemia
• Patients who understand the risks and benefits of treatment, as well as alternatives, and can voluntarily sign the informed consent form

Exclusion Criteria:

• Patients with hypersensitivity or contraindications to statins or ezetimibe
• Patients with active liver disease or persistently elevated AST or ALT levels exceeding three times the upper limit of normal
• Patients with a history of organ transplantation (kidney, liver, etc.)
• Pregnant or lactating women
• Patients with a life expectancy of less than one year due to non-cardiac disease, or those deemed unable to participate in the study and follow-up (based on the medical judgment of the investigator at each site)