Abstract: Objective To investigate the relationship between plasma lipoprotein associated phospholipase A2 (LpPLA2) level and in-stent restenosis (ISR) after percutaneous coronary intervention (PCI). Methods A total of 208 patients treated with PCI and examined with a follow-up coronary angiograph (CAG) were included in this study. The patients were divided into 2 groups based on the results of ISR condition: ISR group (n=29) and NISR group (n=179). The plasma levels of Lp-PLA2 were detected before first-PCI operation and follow-up CAG in two groups. The general clinical data, biochemical parameters, coronary coronariography, interventional features and plasma levels of Lp-PLA2 were compared between the two groups. Logistic regression analysis was used to analyze the independent risk factor for ISR. Receiver operating characteristic curve was used to evaluate the predictive ability of the plasma level of Lp-PLA2 to the occurrence of ISR. Results (1) In ISR group, patients with the history of type 2 diabetes, levels of low density lipoprotein cholesterol (LDL-C) and levels of glycosylated hemoglobin (HbA1c) were significantly higher than those in NISR group, while serum levels of total bilirubin (T- BIL) decreased, the length of the stent was longer, and stent diameter was smaller (P＜0.05). (2) In ISR group, the Lp-PLA2 level and ΔLp-PLA2 level were higher before first-PCI operation than those in NISR group (P＜0.05). (3) Logistic regression analysis showed that T-BIL, stent diameter and ΔLp-PLA2 were the independent risk factors for ISR (P＜0.05). (4) The receiver operating characteristic curve (ROC) area of ΔLp-PLA2 for predicting post-PCI ISR occurrence was 0.862, the optimal cut off value of ΔLp-PLA2 was 20.68 μg/L, the sensitivity was 79%, and the specificity was 83%. Conclusion The increased level of Lp-PLA2 after PCI is correlated with ISR, and the regular monitoring the level of Lp-PLA2 has some significance in forecasting ISR.

Key words: coronary heart disease, lipoprotein associated phospholipase A2, percutaneous coronary intervention, instent restenosis