Lijuan Fan, Presenter: Nothing to Disclose

Dong Li, Abstract Co-Author: Nothing to Disclose

Tie-lian Yu, Abstract Co-Author: Nothing to Disclose

To systematically assess the characteristics of individual calcified plaques, especially in terms of calcium concentration (CC) and constituent ratio of each part segmented by CT value, and to approach the potentials of these parameters in assessing the coronary event risk and plaque progression and regression.

Coronary artery calcium (CAC) was retrospectively analyzed in 186 successive participants with detectable CAC using smartscore sequence by prospectively ECG-triggered 16-SCT. We determined CC, mean CT value, calcified volume (CV), Agatston score (AS), volume score (VS), and mineral mass (MM) of all individual calcified plaque in each subject. Additionally, we segmented each individual calcified plaque by 130~199Hu, 200~299Hu, 300~399Hu, and ≥ 400Hu and obtained the constituent ratio of each part. Statistical analysis was performed by using Spearman rank correlation test and rank test.

We identified a total of 689 calcified coronary plaques. Positive correlations could be found between CC and CV, VS, and MM. CC was significantly different among age groups (P=0.000) and between men and women (P=0.025). Among a subgroup of 86 subjects with multiple (≥3) individual calcified plaques, CC was heterogeneous within individual subjects (mean SD of CC, 53.89±27.85mg/cm3). The degree of heterogeneity of CC in these subjects was independent of sex (P=0.704) and number of plaques (P=0.678), but was significantly different among age groups (P=0.028). Except the constituent ratio of 200~299Hu, other three kinds of constituent ratios were significantly different among age groups (P<0.05) and between men and women (P<0.05) and had significant relevance correlation with other parameters (P<0.05).

The characteristics of CC and CT value may reflect the pathological process of calcified plaques.

The characteristics of individual calcified plaques assessing by CT may provide more valuable information to understand the plaque stability and plaque progression and regression.

Fan, L, Li, D, Yu, T, Quantification of Individual Coronary Artery Calcified Plaques as Measured by MSCT.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/5008362.html