Abstract 15225: Quantitative Assessment of Echo-Attenuated Plaque by Optical Coherence Tomography and its Impact on Post-Procedural CK-MB Elevation in Elective Stent Implantation
Background: Recent intravascular ultrasound (IVUS) studies have described atherosclerotic plaques with echo attenuation (EA) without associated bright echoes that are correlated with no-reflow phenomenon after percutaneous coronary intervention (PCI). Plaques with EA have been reported to show high-risk plaque characteristics on OCT. We sought to perform quantitative assessment of IVUS and OCT findings of the lesions with EA to predict post-PCI CK-MB elevation (>16 IU/L) in elective stenting.
Methods and Results: We enrolled 226 native de novo culprit coronary lesions from 204 patients with normal pre-PCI CK-MB levels who underwent IVUS and OCT examinations before elective stent implantation. The presence of EA on IVUS was defined as a plaque showing echo signal attenuation >90° for more than 1mm without dense calcification. EA was observed 65 lesions with 65 patients (29%, 10: unstable angina; 55: stable angina). These 65 EA lesions were divided into two groups with or without post PCI CK-MB elevation, and IVUS and OCT findings were compared. Furthermore, receiver operating characteristic (ROC) curve analysis was performed to define the best cut-off value to discriminate post-PCI CK-MB elevation. Post-PCI CK-MB elevation was observed 29 lesions (45%). Post-PCI CK-MB elevation was associated with longitudinal length of EA (median: 7.5 mm, IQR: 4.0-10.1 vs median: 3.7 mm, IQR: 2.6-4.8, P < 0.001), quadrants of EA (median: 3, IQR: 2-3 vs median: 2, IQR: 2-3, P = 0.001), %plaque area (89.9±3.9% vs 86.8±4.7%, P = 0.005), remodeling index (1.12±0.18 vs 1.01±0.18, P = 0.017), OCT-derived thin-capped fibroatheroma (TCFA; 76% vs 28%, P < 0.001), and ruptured plaque (45% vs 19%, P = 0.034). In multivariable analysis, EA length (OR, 1.46; 95% CI, 1.14-1.85, P = 0.002) and the incidence of TCFA (OR, 6.42; 95% CI, 1.82-22.59, P = 0.004) were independent predictors of post-PCI CK-MB elevation. ROC analysis showed the best cut off values of EA length for post CK-MB elevation was 6.6mm (AUC: 0.77, sensitivity: 59%, specificity: 94%). Lesions with EA length > 6.6mm and TCFA represented high-risk for post-PCI CK-MB elevation (OR, 6.72; 95%CI, 1.66-27.26; P = 0.008).
Conclusions: Longitudinal length of EA on IVUS and OCT-derived TCFA were predictors for post CK-MB elevation.
- Intravascular ultrasound/Doppler
- Percutaneous coronary intervention
- Myocardial infarction
- Vulnerable plaque
- © 2011 by American Heart Association, Inc.