The characteristics and risk factors of in-stent restenosis in patients with percutaneous coronary intervention: what can we do

Background: Percutaneous coronary intervention (PCI) is a common treatment for patients with coronary heart disease, and intra-stent restenosis (ISR) is a serious complication after PCI. It’s necessary to identify the potential risk factors to provide evidence for the prevention of ISR. Methods: The patients who underwent coronary angiography 1 year after PCI in our hospital from January 2017 to May 2019 were selected. The characteristics and results of clinical examination of ISR and no-ISR patients were compared, Multivariate logistic regression analyses were performed to identify the risk factors. Results: A total of 209 patients were included, the incidence of ISR after PCI was 30.62%. There were significant differences on the hypertension, diabetes, number of coronary artery lesions, reasons for stent implantation, the diameter of stent, the length of stent and stent position between ISR group and no-ISR patients (all p < 0.05). The LDL-C in ISR groups was significantly higher than that of no-ISR group (p = 0.048), there were no significant differences between two groups in FPG, TG, TC, HDL-C, Apo A1, Apo B, LP-a and glycated haemoglobin (all p > 0.05). The hypertension (OR 4.30, 95% CI 1.12–9.34), diabetes (OR 5.29, 95% CI 1.25–9.01), number of coronary artery lesions ≥ 2 (OR 4.84, 95% CI 1.21–9.55), LDL-C ≥ 1.9 mmol/L (OR 5.93, 95% CI 2.29–10.01), unstable angina (OR 2.92, 95% CI 1.20–4.55), left anterior descending artery (OR 4.01, 95% CI 1.73–7.58), diameter of stent ≥ 3 mm (OR 5.42, 95% CI 1.24–10.84), the length of stent > 20 mm (OR 3.06, 95% CI 1.19–5.22) were the independent risk factor for ISR (all p < 0.05). Conclusion: It is necessary to take preventive measures against these risk factors to reduce ISR, and studies with larger sample size and longer follow-up on this issue are needed in the future.