Results Eighty-three patients were included in the final analysis after the initial screening. Sixty (72.3%) were acute coronary syndrome (ACS) patients and 23 (27.7%) were stable angina pectoris (SAP) patients. Plaque rupture occurred in 39 (47.0%) patients, and 34 (87.2%) were from ACS patients and 5 (12.8%) from SAP patients. There were no significant differences in clinical and angiographic characteristics between patients with plaque rupture and those without plaque rupture, except for smoking, high-sensitive C-reactive protein (hs-CRP) level and Lp-PLA
2 activity (all
P <0.05). IVUS measurement uncovered that patients with plaque rupture had more frequent positive remodeling (74.4% vs. 43.2%,
P=0.004), soft plaques (64.1% vs. 36.4%,
P=0.012) and higher remodeling index (1.13±0.16 vs. 0.99±0.11,
P=0.041) as compared with those without plaque rupture. Multivariate Logistic regression analysis showed that plasma Lp-PLA
2 activity was independently associated with plaque rupture after adjusting for smoking, positive remodeling and soft plaque (Model 1: odds ratio (
OR) 1.13, 95% confidence interval (
CI) : 1.06
–1.20) or adjusting for smoking, hs-CRP level, positive remodeling and soft plaque (Model 2:
OR 1.11, 95%
CI: 1.04–1.19).