Association between periprocedural myocardial injury and neointimal characteristics in patients with in-stent restenosis: an optical coherence tomography study

Background: The relationship between neointimal characteristics of in-stent restenosis (ISR) and periprocedural myocardial injury (PMI) remains unclear. Therefore, this study aimed to investigate the relationship between PMI and neointimal characteristics of ISR by using optical coherence tomography (OCT). Methods: This was a retrospective study. We enrolled 140 patients diagnosed with ISR with normal baseline high -sensitivity troponin T (hs-cTnT) levels who underwent OCT and subsequent revascularization by means of drug -coated balloon (DCB) or drug -eluting stent (DES) between October 2018 and October 2022 in the Affiliated Hospital of Zunyi Medical University. Based on the 4th universal definition of myocardial infarction, patients whose hs-cTnT were increased five times above the upper reference limit (URL) after percutaneous coronary interventions (PCI) were deemed to PMI. The patients were subdivided into PMI (n=53) and non-PMI (n=87) groups. In the univariable analysis, variables in the baselines, angiography characteristics and OCT findings were analyzed with binary logistic regression. A P value of <0.2 was included in the multivariable model. Multivariable logistic regression analysis was used to identify the independent predictors of PMI. Results: The prevalence of intra-intimal microvessels in patients with PMI was higher than in those without PMI (58.5% vs. 32.2%, P=0.003). The ratio of intra-stent plaque rupture (PR) was also higher in patients with PMI (60.4% vs. 40.2%, P=0.021). Multivariable logistic regression analysis showed that intraintimal microvessels [odds ratio (OR): 3.193, 95% confidence interval (CI): 1.280-7.966; P=0.013] and intrastent PR (OR: 2.124, 95% CI: 1.153-4.732; P=0.035) were independently associated with PMI. Conclusions: Intra-intimal microvessels and intra-stent PR were independently associated with PMI. Accurate identification and recognition of intra-intimal microvessels and intra-stent PR may be helpful in preventing PMI.