Abstract
Patients with acute myocardial infarction are found to have layered plaque in the culprit lesion site during optical coherence tomography, indicating that these patients have experienced recurrent thrombotic events locally. Whether inflammation factors are associated with this phenomenon remains unknown. A total of 125 patients with acute myocardial infarction who underwent coronary angiography followed by optical coherence tomography were prospectively enrolled. 17 patients were excluded due to various reasons. Peripheral blood samples were collected from all patients, and blood samples from the culprit vessel were collected during thrombus aspiration in a subset. All optical coherence tomography images of the culprit vessels were analyzed as well as quantitative coronary angiography. The mRNA expression of IL-1β, IL-4, IL-8, IL-10, IL-18, ELANE, MPO in monocytes of both peripheral and culprit lesion blood samples were analyzed. Of the 108 eligible patients, 56 (51.9%) had layered plaque at the site of the culprit lesion. Clinical characteristics and quantitative coronary angiography showed no significant difference between the layered plaque and non-layered plaque groups. Layered plaque group had greater mean lipid arc (304.23° [284.52, 330.80] vs 288.16° [256.00, 311.00], p=0.047). Peripheral blood samples revealed no difference in any inflammatory factors expression, however, higher mRNA expression level of IL-1β in culprit lesion blood was observed in layered plaque group, with a mean difference of 1.81 (95% BCa CI [0.66, 3.10], p =0.023). Firth's penalized likelihood logistic regression analysis showed that mRNA expression level of IL-1β was significantly associated with layered plaque (OR, 1.78, 95% CI, 1.16-3.29, p=0.005) after adjusting for age and sex. ROC analysis demonstrated that IL-1β yielded an AUC of 0.781 (95% CI: 0.637-0.924) for predicting layered plaque. IL-1β was expressed more in the culprit vessel in patients whose culprit lesion showed layered plaque, proving that local IL-1β is associated with layered plaque.