Abstract 2794: Assessment Of Atherosclerotic Plaque Characteristics By Multi-detector Row Computed Tomography: Comparison With Integrated Backscatter Intravascular Ultrasound
Background: Multi-detector row computed tomography (MDCT) has shown to be useful as noninvasive assessment for coronary artery disease. However, the ability of MDCT to differentiate plaque types remains unclear yet. We sought to investigate whether density of plaque by MDCT correlates with plaque composition assessed with integrated backscatter intravascular ultrasound (IB-IVUS).
Method: 88 consecutive patients were investigated by MDCT before scheduled coronary angiography. 108 lesions in 88 patients were evaluated with IVUS and IB-IVUS when the lesion was suspected to have > 50% stenosis angiographically. Based on IB-IVUS analysis, tissue components were classified into calcified, dense fibrous, fibrous tissue and lipid core. The CT density (HU) within plaque was measured at the corresponding location in IB-IVUS.
Results: 106 lesions showed atherosclerotic plaque with >50% stenosis among 108 lesions evaluated by IB-IVUS. Plaque was identified in 89 lesions by MDCT (sensitivity 84%). In only 1 lesion diagnosed to have plaque with MDCT, IB-IVUS showed normal coronary artery (positive predictive value 99%). The mean relative content of calcified, dense fibrous, fibrous tissue, and lipid core by IB-IVUS was 2.10±2.16%, 5.90±6.21%, 47.93±14.34%, and 36.40±12.37%, respectively. There was a significant positive correlation between the CT density and the calcified tissue content in percent (r=0.416, p<0.001). However, the density of plaques on MDCT showed no correlation with other plaque content.
Conclusion: The plaque density measured by MDCT was helpful to identify calcified atherosclerotic plaque, but could not differentiate plaque types of noncalcified lesion.