Abstract 4474: Coronary Plaque Composition in Unstable Angina Predicts Myonecrosis after Coronary Artery Stenting : A Study with Virtual Histology Intavascular Ultrasound
The purpose of this study was to assess the relationship between plaque composition determined by Virtual Histology intravascular ultrasound (VH-IVUS) and elevated cardiac enzyme after coronary artery stenting in unstable angina. A total of 77 patients with unstable angina were prospectively included. We excluded 17 patients with side branch occlusion and the other 60 patients were divided into two groups after elective stenting: CK-MB elevation (CK Group, n= 17) and no CK-MB elevation (non-CK group, n= 43). Coronary plaque tissue maps were reconstructed from VH-IVUS software (Volcano Therapeutics, Inc., Rancho Cordova, California). Necrotic core percentage was significantly higher in the CK group than that in the non-CK group (21.6 +/− 11.3 % vs. 14.4 +/− 10.0 %, p < 0.018). Total plaque volume was similar in both groups. Multivariate analysis demonstrated that female sex (OR 5.85, 95% CI 1.04±32.9, p=0.045) and necrotic core percentage (OR 1.09, 95% CI 1.01±1.17, p=0.038) were independent predictors of CK-MB elevation after coronary stenting. On receiver-operating characteristic analysis, the best cut-off value of necrotic core percentage for prediction of CK-MB elevation was 15% with a sensitivity of 73.6% and a specificity of 53.5%. The necrotic core percentage identified by VH-IVUS is independently predictive of future CK-MB elevation after coronary artery stenting in unstable angina.