Table 3

Gray-Scale and IB-IVUS Measurements

Non-TCFA (n = 41)TCFA (n = 40)p value
EEM CSA (mm2)11.3 ± 3.415.8 ± 4.3<0.0001
Lumen CSA (mm2)3.5 ± 1.54.1 ± 1.80.11
P+M CSA (mm2)7.8 ± 2.511.7 ± 4.1<0.0001
Plaque burden (%)69.2 ± 8.173.5 ± 10.1<0.05
Remodeling index0.95 ± 0.141.08 ± 0.15<0.0001
% fibrosis area (%)51.1 ± 9.534.7 ± 9.5<0.0001
% dense fibrosis area (%)7.3 ± 4.22.5 ± 2.0<0.0001
% calcification area (%)3.1 ± 2.60.7 ± 1.0<0.0001
% lipid pool area (%)38.6 ± 12.862.1 ± 10.8<0.0001
Fibrosis area (mm2)3.92 ± 1.123.98 ± 1.530.73
Dense fibrosis area (mm2)0.52 ± 0.280.28 ± 0.22<0.0001
Calcification area (mm2)0.23 ± 0.190.08 ± 0.11<0.0001
Lipid pool area (mm2)3.18 ± 1.637.34 ± 3.15<0.0001

Data are mean ± SD. Remodeling index was defined as ratio of lesion to reference external elastic membrane (EEM) cross-sectional area (CSA) (the average of the proximal and distal reference segments).

IB-IVUS = integrated backscatter intravascular ultrasound; P+M = plaque plus media; TCFA = thin-cap fibroatheroma.