Abstract 17237: The Underlying Necrotic Core is a Determinant of Occlusive Thrombosis
Background: It is well known that plaque rupture is not always associated acute coronary syndrome and in fact 10% of asymptomatic individuals dying of other causes have plaque rupture. To identify the underlying mechanisms of high risk plaque that leads to occlusive thrombosis, we examined coronary plaques from our registry of sudden coronary death victims.
Methods and Results: From our sudden coronary death registry, 102 plaque ruptures (PR) were identified in proximal and middle segments of coronary trees; distal lesions were excluded. Histomorphometric area measurements included EEL, IEL, lumen, necrotic core (NC), calcification, and macrophage positivity (CD68) at the cross-section of rupture site. In addition, thinnest portion of fibrous cap adjacent to rupture site was measured. The lesions with PR were categorized into 2 groups: occlusive (>75% luminal thrombus) or non-occlusive (<75% luminal thrombus). PRs with occlusive thrombosis was associated with larger IEL area, larger NC, thicker fibrous cap as compared to those with non-occlusive thrombosis while EEL, lumen, calcification, and macrophage area were similar in both groups (Table). Multivariate regression analysis revealed that total NC volume is the best predictor of occlusive thrombus with an odds ratio of 1.15 (p=0.019), followed by cap thickness (odds: 1.04, p=0.024). ROC analysis of NC demonstrated the threshold of 2.89 mm2 with sensitivity 0.61 and specificity 0.67 (AUC 0.67).
Conclusion: These data suggest that strategies directed at detection of precise necrotic core area are necessary to assess high risk coronary plaques.
- © 2011 by American Heart Association, Inc.