Neointimal Features in Patients With Restenosis of Calcified Lesions

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

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

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.

Inclusion Criteria:

1. The patient is older than 18 years.
2. The patient had undergone coronary angiography at our hospital for PCI and had first ISR with drug-eluting stent implantation.
3. Calcified lesion greater than 5 mm in length.
4. Stent implantation time greater than 30 days.

Exclusion Criteria:

1. Bridge vessel lesions following coronary artery bypass grafting.
2. Planned modification of the DAPT regimen for medical reasons or other surgical procedures requiring modification within 3 months of the index procedure.
3. Patients undergoing heart transplantation.
4. Significant angiogenic lesions in the target vessel that may prevent stent delivery and deployment.
5. Bifurcation disease lesions involving collateral branches ≥ 2.5 mm in diameter.
6. Lesions deemed by the investigator to be unsuitable for OCT imaging (e.g., extremely curved, very distal lesions).
7. Serum creatinine > 2.0 mg/dl at the time of treatment.
8. Greater than three types of stent implantation.
9. 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).