Relationship Between Conventional Cardiovascular Risk Factors,lp-PLA2 Concentration And Plaque Structure Parameters

Objective:The purpose of this study was to examine the relationship between conventional cardiovascular risk factors,Lp-PLA2 concentration and plaque structure parameters assessed by the intravascular ultrasound in patients with either stable angina or acute coronary syndromes due to intermediate single-vessel coronary artery lesions.Methods: 192 patients with single vessel and intermediate coronary lesions identified by angiography were enrolled in a cross-sectional study and divided into two groups: stable angina pectoris(SAP)and acute coronary syndrome(ACS).Baseline data including Lp-PLA2 were collected.Using i MAP-IVUS,areas of lumen were manually traced to determinethe minimum lumen area(MLA)at every 1-mm interval in diseased segments.At the minimum lumen lesion,areas of different types of atherosclerotic tissue [i.e.areas of fibrous plaque tissue(FPA),fibro-fatty tissue(FFA),dense calcium(DCA)and necrotic core(NCA)],vascular external elastic membrane(EEMCSA)and plaque and media(P&MCSA)were calculated by the built-in i Map algorithm.Plaque burden was computed as P&MCSA divided by EEMCSA.Univariate predictors were got using linear regression analysis to determine the risk factors for dependent variable.Logistic regression is used to determine risk factors of ACS and ROC curve is used to describe the diagnostic value.Results:(1)Compared to the SAP group,ACS group had higher population proportions in the history of smoking and diabetes,higher LDL-C value and Lp-PLA2 mass,and a lower HDL-C value.(2)Compared to SAP group,The values of EEMCSA,P&MCSA,plaque burden,and areas of FP and NC were all higher in ACS group,while with lower values of DCA.(3)In univariate analysis,For FPA and plaque burden,GHb A1 C,total cholesterol,triglycerides,LDL-C,and Lp-PLA2 were predictors of more severe disease,HDL-C and statins were the protective factors.For NCA,GHb A1 C,total cholesterol,LDL-C,age,hypertension,and Lp-PLA2 were predictors of more severe disease,HDL-C was a protective factor.There were no significant predictors for FFA and DCA.The results of regression analyses were not exactly the same when analyses separately in SAP and ACS groups whether in univariate analysis or in multivariate analysis.(4)After adjustment for other risk factors,both Lp-PLA2 and GHb A1 C remained independent predictor of more severe disease for plaque burden as well as FPA and NCA.HDL-C remained a protective factor either for plaque burden or FPA in agreement with univariate regression models.Suffering from hypertension was independently associated with increased NCA.(5)Lp-PLA2,diabetes and NCA were significant predictors of acute coronary lesions and the predictive value of Lp-PLA2 and NCA were confirmed by high area-under-the curve in ROC analysis as well as by the reasonable sensitivity and specificity of cut-off values.Conclusions: GHbA1 C and Lp-PLA2 were strong independent predictorsof plaque burden,FPA and NCA at the minimum lumen lesion in patients with single vessel and intermediate coronary lesions.Cholesterol,hypertension and statins had some predicted values for plaque index.Lp-PLA2 and NCA were confirmed by high area-under-the curve in ROC analysis as well as by the reasonable sensitivity and specificity of cut-off values.