BackgroundSpectral analysis of IVUS radiofrequency(RF) data has the potential to provide detailed quantitative information on plaque composition. The purpose of this study was to assess the relationship between plaque composition determined by IVUS-RF data analysis and elevated cardiac enzyme after coronary artery stenting in unstable angina.Methods and ResultsThis study included 61 consecutive patients of unstable angina undergoing coronary artery stenting from September 2005 to July 2006 . After stenting, the population was prospectively divided into two groups; CK-MB elevation (Group 1, n= 17patients) and no CK-MB elevation (Group 2, n= 44patients). Coronary plaque tissue maps were reconstructed from RF data using IVUS-Virtual Histology(VH) software. Mean percentage of lipid core was significantly larger in Group 1 when compared with Group 2 (24.76% 짹 11.5% vs 14.81% 짹 9.9%, p=0.001). Multivariate analysis demonstrated that female sex (p=0.017), post stenting side branch occlusion (p=0.002), and percentage of lipid core (p=0.038) remained independent predictors of CK-MB elevation after coronary stenting.ConclusionsThe percentage of lipid core identified by IVUS- VH is independently predictive of future CK-MB elevation after coronary artery stenting. These data support that coronary plaque composition data using IVUH-RF analysis can be used as a valuable tool to predict microembolization after coronary stenting.