Is lipoprotein-associated phospholipase A2 activity correlated with fibrous-cap thickness and plaque volume in patients with acute coronary syndrome?

BackgroundLipoprotein-associated phospholipase A(2) (Lp-PLA(2)) is a specific biomarker specific for vascular inflammation. Inflammation has a significant association with plaque progression. The fibrous-cap thickness (FCT) is one of the major determinants of plaque vulnerability in atherosclerotic plaques. However, data on the relationship between Lp-PLA(2) activity and FCT in lipid plaque are limited. This study aimed to evaluate the in-vivo association between changes in Lp-PLA(2) activity and FCT and plaque volume in patients with acute coronary syndrome (ACS).Patients and methodsTwenty-four consecutive patients with ACS were enrolled between May 2010 and May 2012. The plaque volume and FCT of nonculprit lipid-rich plaques were assessed by intravascular ultrasound and optical coherence tomography, respectively, at baseline and after 12 months. Lp-PLA(2) activity was determined using the colorimetric assay kit.ResultsDuring the 12 months of observation, FCT increased significantly from baseline to follow-up, with a mean percent change of 74.446.8%. A significant correlation was observed between changes in Lp-PLA(2) activity and changes in FCT (r=-0.56, P=0.006). Changes in plaque volume were also correlated significantly with changes in Lp-PLA(2) activity during the study period (r=0.52, P=0.01).ConclusionSignificant associations between serial changes in Lp-PLA(2) activity and changes in FCT and plaque volume were observed in patients with ACS.