Aim. To study the effect of high-dose combined lipid-lowering therapy (statins + ezetimibe vs statins + PCSK9 inhibitors) on plaque vulnerability assessed using multimodal imaging (coronary computed tomography angiography (CCTA) and optical coherence tomography, as well as biomarkers in patients with acute coronary syndrome (ACS).Material and methods. This open, prospective, randomized, single-center study will include 120 patients admitted urgently with an ACS. All patients will undergo percutaneous coronary intervention of the infarct-related artery, as well as intracoronary imaging using optical coherence tomography of one or two noninfarct-related arteries. During hospitalization, patients will receive standard therapy for ACS according to clinical guidelines, while statins will initially be prescribed at a maximum dosage of atorvastatin 80 mg/rosuvastatin 40 mg.Patients who showed high compliance and did not reach the target low-density lipoprotein cholesterol (LDL-C) values (≤1,4 mmol/l) 1 month after myocardial infarction/unstable angina at the second visit will be randomized into two groups. Patients of group 1 will receive PCSK9 inhibitors (alirocumab 150 mg by subcutaneous injection once every 2 weeks or evolocumab 140 mg by subcutaneous injection once every 2 weeks) in addition to maximum statin therapy (atorvastatin 80 mg/rosuvastatin 40 mg), while group 2 participants will take ezetimibe at a dose of 10 mg in combination with the maximum dose of statins. In addition, at the second visit, patients will undergo CCTA, assess the cardio-ankle vascular index (CAVI) index and laboratory tests (complete blood count (neutrophil-to-lymphocyte ratio NLR), lipid profile, alanine aminotransferase (ALT), aspartate aminotransferase (AST), Troponin I, Galectin-3, high-sensitivity C-reactive protein (hs-CRP), metalloproteinase-9 (MMP-9), tissue inhibitor of metalloproteinase 1 (TIMP-1), neutrophil gelatinase-associated lipocalin (NGAL). Total follow-up will last 52 weeks. At the final visit, patients will undergo CCTA, assessment of the CAVI index and laboratory status (NLR, lipid profile, ALT, AST), Troponin I, Galectin-3, hs-CRP, MMP-9, TIMP-1, NGAL).Primary endpoint: reduction in plaque vulnerability according CCTA in non-infarct-related coronary arteries Secondary endpoints: death, stent thrombosis/restenosis, non-fatal myocardial infarction, readmissions with progressive angina, repeat revascularization; changes of the lipid profile (total cholesterol, LDL-C, high-density lipoprotein cholesterol, triglycerides) against the background of maximum combination therapy with statin + PCSK9 inhibitors or statin + ezetimibe; changes of the biomarkers of cardiac injury (Troponin I), inflammation (NLR, hs-CRP, NGAL, Galectin-3) and matrix remodeling (MMP-9, TIMP-1).Conclusion. Our study will allow for the first time to compare and evaluate the effect of both PCSK9 inhibitors and ezetimibe in combination with high-dose statin therapy on reducing the plaque vulnerability according to CCTA in non-infarction-related coronary arteries in patients with ACS undergoing percutaneous coronary intervention, as well as to evaluate the diagnostic value of inflammatory biomarkers (NLR, hs-CRP, NGAL, Galectin-3) and matrix remodeling (MMP-9, TIMP-1).
