Previous studies have shown that plaque rupture (PR) is the most important cause of acute coronary syndrome (ACS). However, the potential impact of intra-stent PR on stent failure manifesting as ACS and the optical coherence tomography (OCT) features of these lesions was still less clear. Therefore, we aimed to investigate the characteristics of OCT-defined in-stent PR and identify the potential risk factors for PR in ACS patients. All 213 ACS patients were stratified into two groups according to the occurrence of in-stent PR. The baseline characteristics of all patients were investigated. A multivariable logistic regression was performed to identify factors associated with the formation of PR. OCT findings showed that 80 patients had in-stent PR, and 133 patients were without PR. Patients who suffered in-stent PR had higher blood lipid levels (P < .050) and longer duration of stent failure (P = .001). Moreover, thrombolysis in myocardial infarction (TIMI) 0/1 flow was more prone to the formation of PR (P = .010), and lesions in the PR group harbored more macrophages and cholesterol crystals (P < .001 and P = .024). On multivariate analysis, presentation of myocardial infarction (MI) and OCT findings of lipidic neointima length showed a 3.6-fold (P = .004) and 1.3-fold (P < .001) higher risk for occurrence of in-stent PR. ACS patients who suffered in-stent PR had a longer duration of stent failure and more ISR occurring in non-culprit vessels. Given the distinguishing features between ACS patients with in-stent PR and non-PR, potential targeted therapy was warranted to improve the prognosis of patients with in-stent PR.
Keywords: acute coronary syndrome; in-stent restenosis; neoatherosclerosis; optical coherence tomography; plaque rupture.