Neointimal Features in Patients With Restenosis of Calcified Lesions

Study Overview
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Brief Summary
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Previous studies have suggested that restenosis (RS) after stenting is mainly due to smooth muscle cell proliferation and migration, but recent evidence suggests that in-stent restenosis（ISR） is associated with a number of factors. Coronary artery calcification is an independent predictor of ischaemia-mediated revascularisation 1 year after percutaneous coronary intervention (PCI) following RS.The characteristics of new neointima in patients with in-stent restenosis of calcified lesions are important issues to explore

Detailed Description
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The characteristics of the endothelium after DES following implantation of calcified lesions have always been of interest to us. Its inherent peculiarities make the new endothelium of calcified lesions different. Firstly, the presence of calcification makes the neointima heal slowly. In addition DES has an anti-proliferative effect, which further diminishes the healing ability of the neointima of calcified lesions and impairs the barrier function of the endothelium. This may have a similar pathway to the formation of neointimal atherosclerosis or heterogeneous endothelium within the neointima. Secondly, stents with calcified lesions can be accompanied by incomplete stent expansion, stent fracture and stent misalignment. These conditions may accelerate the occurrence of restenosis within the stent. Thirdly, there are different types of calcified lesions. Different types of calcified lesions may heal and restenosis in different ways. It is therefore understood that calcified lesion healing has a number of pathways that exist in contradiction. These are issues that need to be explored in depth.

Official Title
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Characteristics of Intimal and Neoatherosclerosis in Patients With Restenosis After DES Implantation for Calcified Lesions

Conditions
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Coronary Artery Calcification, Restenosis, Neointima, Neoatherosclerosis

Intervention / Treatment
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* Other: Coronary artery calcification lesions


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: The patient is older than 18 years. The patient had undergone coronary angiography at our hospital for PCI and had first ISR with drug-eluting stent implantation. Calcified lesion greater than 5 mm in length. Stent implantation time greater than 30 days. Exclusion Criteria: Bridge vessel lesions following coronary artery bypass grafting. Planned modification of the DAPT regimen for medical reasons or other surgical procedures requiring modification within 3 months of the index procedure. Patients undergoing heart transplantation. Significant angiogenic lesions in the target vessel that may prevent stent delivery and deployment. Bifurcation disease lesions involving collateral branches ≥ 2.5 mm in diameter. Lesions deemed by the investigator to be unsuitable for OCT imaging (e.g., extremely curved, very distal lesions). Serum creatinine > 2.0 mg/dl at the time of treatment. Greater than three types of stent implantation. Subjects with malignancy or other co-morbidities (i.e., severe liver, kidney, lung, or pancreatic disease with a life expectancy of less than 18 months or which may result in protocol non-compliance).

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| calcified group<br>A calcified coronary culprit lesion was defined as readily apparent densities noted within the apparent vascular wall at the site of the stenosis. target lesions were classified as severe (radio opacities noted without cardiac motion prior to contrast injection generally involving both sides of the arterial wall),moderate (densities noted only during the cardiac cycle prior to contrast injection).Severe and moderate calcification is classified as a calcified group. | Other: Coronary artery calcification lesions<br>* Calcification of atherosclerosis, a complex, organic, regulated and active process, is one of the manifestations of atherosclerosis. The progression of coronary atherosclerosis is a strong independent predictor of future coronary events. It has been shown that coronary artery calcification affects the healing of the neointima and the function of the endothelium after stenting. This may lead to changes in neointimal morphology and the development of neoatherosclerosis after stent implantation.<br>|
| non-calcified group<br>none/mild(lesions other than severe and moderate calcified lesions). none/mild calcification is classified as a non-calcified group. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean lumen area | Quantitative Indicators，the mean area bounded by the luminal border on OCT（Optical Coherence Tomography） | through study completion, an average of 1 year | 
| Minimum lumen area | Quantitative Indicators，the minimum area bounded by the luminal border on OCT | through study completion, an average of 1 year | 
| Maximum lumen area | Quantitative Indicators，the maximum area bounded by the luminal border on OCT | through study completion, an average of 1 year | 
| Percent area stenosis | Quantitative Indicators，the (reference lumen area minus the minimum lumen area) divided by the reference lumen area, multiplied by 100. The reference segment used should be specified (proximal, distal, largest or average) on OCT | through study completion, an average of 1 year | 
| Mean stent area | Quantitative Indicators，the mean area bounded by the stent border on OCT | through study completion, an average of 1 year | 
| Minimum stent area | Quantitative Indicators，the Minimum area bounded by the stent border on OCT | through study completion, an average of 1 year | 
| Maximum stent area | Quantitative Indicators，the Maximum area bounded by the stent border on OCT | through study completion, an average of 1 year | 
| lipid-laden intima | Qualitative indicators,a diffusely bordered, signal-poor region with overlying signal-rich bands in the intima on OCT.the investigators measured its incidence on OCT. | through study completion, an average of 1 year | 
| Calcification | Qualitative indicators,shows a well-delineated, signal-poor region with sharp borders.the investigators measured its incidence on OCT. | through study completion, an average of 1 year | 
| Thrombi | Qualitative indicators,masses protruding into the lumen and discontinuous from the surface of the vessel wall.the investigators measured its incidence on OCT. | through study completion, an average of 1 year | 
| Intimal rupture | Qualitative indicators,discontinuity of the fibrous cap connecting the lumen.the investigators measured its incidence on OCT. | through study completion, an average of 1 year | 
| Neovascularization | Qualitative indicators,the presence of signal-poor holes or tubular structures with a diameter of 50 to 300 μm that are not connected to the vessel lumen.the investigators measured its incidence on OCT. | through study completion, an average of 1 year | 
| Thin-cap fibroatheroma (TCFA) | containing intima was defined as fibrous cap thickness ≤65 μm at the thinnest segment and an angle of lipid tissue ≥180°.the investigators measured its incidence on OCT. | through study completion, an average of 1 year | 
| Macrophage infiltration | Qualitative indicators,a bright spot with a high signal variance from the surrounding tissue.the investigators measured its incidence on OCT. | through study completion, an average of 1 year | 
| Stent underexpansion | Qualitative indicators,Stent expansion describes the minimum stent cross-sectional area either as an absolute measure (absolute expansion), or compared with the predefined reference area, which can be the proximal, distal, largest, or average reference area (relative expansion).the investigators measured its incidence on OCT. | through study completion, an average of 1 year | 
| stent fracture | Qualitative indicators,the interruption of stent continuity.the investigators measured its incidence on OCT. | through study completion, an average of 1 year | 
| Uncovered struts | the ratio of uncovered-to-total stent struts per section was calculated and expressed as percent on OCT. | through study completion, an average of 1 year | 
| neoatherosclerosis | neoatherosclerosis were defined by the presence of one or more of the following: lipid laden tissue ，thin-cap fibroatheroma (TCFA)，neointimal calcification，Macrophage infiltration.the investigators measured its incidence . | through study completion, an average of 1 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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coronary artery calcification, ISR, neoatherosclerosis