Chronic total occlusions (CTOs) are found in 15-25% of patients with stable angina pectoris. The presence of a CTO indicates unfavorable prognosis, with higher rate of major adverse cardiovascular events. Statins are frequently used after PCI in order to lower LDL cholesterol levels and reduce the chances of coronary artery obstruction recurring. Despite this preventive measure, high risk for restenosis and re-occlusion was observed a significant proportion of patients with CTOs undergoing PCI.~Proprotein convertase subtilisin/kexin type-9 (PCSK9) inhibitors represent a novel class of lipid-lowering drugs leading to rapid, profound, and consistent reductions in LDL-C levels. The effect of PCSK9 inhibitor in patients with CTO, after a recent PCI is not known.~In this study the investigators want to evaluate the effect of the PCSK9 inhibitor on neointimal hyperplasia and target lesion failure (TLF) in patients with CTOs receiving regular statin treatment. A serial of intravascular ultrasound imaging study will be performed to determine the restenosis at 48 weeks.
The purpose of this study is to evaluate the effect of proprotein convertase subtilisin/kexin type-9 (PCSK9) inhibitors added to regular statin therapy on neointimal hyperplasia and target lesion failure (TLF) in patients with chronic total occlusions (CTOs) undergoing successful percutaneous coronary intervention (PCI).