Prospective, head-to-head comparison of quantitative coronary angiography, quantitative computed tomography angiography, and intravascular ultrasound for the prediction of hemodynamic significance in intermediate and severe lesions, using fractional flow reserve as reference standard (from the ATLANTA I and II Study).

The objective of this study was to compare the diagnostic accuracy of quantitative coronary angiography (QCA), coronary computed tomography angiography (CTA), and intravascular ultrasound (IVUS) with fractional flow reserve (FFR) measurements. Eighty-five lesions (40% to 99% diameter stenosis) in 85 patients were prospectively interrogated by QCA, CTA, IVUS, and FFR. Minimal lumen diameter (MLD), percent diameter stenosis (%DS), minimal lumen area (MLA), and percent area stenosis (%AS) were measured. Correlation, receiver operating characteristic analysis, kappa statistics, and multivariable logistic regression was used to assess relation between anatomic measurements and FFR. Average age was 61.3 ± 7.8; 62% were men. QCA-derived mean %DS was 55.3% ± 19.5%; mean FFR 0.81 ± 0.17; 27% had FFR ≤0.75. QCA had the strongest correlation, followed by CTA and then IVUS for MLD (r = 0.67, 0.47, and 0.29, respectively) and for %DS (r = -0.63, -0.52, and -0.22, respectively); QCA-derived MLD had area under the curve of 0.96, with 95% sensitivity and 82% specificity. Cut-point, area under the curve, sensitivity, and specificity for CTA-MLA and IVUS-MLA were 3.11 mm(2), 0.86, 81%, and 81% and 2.68 mm(2), 0.75, 70%, and 80%. In multivariable analysis for each modality, MLD on QCA (odds ratio [OR]: 0.002), %AS on CTA (OR: 1.09) and MLA on IVUS (OR: 0.28) remained independent predictors. In conclusion, in intermediate-to-severe lesions, QCA-, CTA-, and IVUS-derived quantitative anatomic measurements correlated with FFR. CTA-derived cut-points were similar to respective measurements on QCA and IVUS and had similar or better diagnostic performance compared with IVUS.

Apoprotein B, small-dense LDL and impaired HDL remodeling is associated with larger plaque burden and more noncalcified plaque as assessed by coronary CT angiography and intravascular ultrasound with radiofrequency backscatter: results from the ATLANTA I study.

BACKGROUND: Apoprotein B-containing lipoproteins are atherogenic, but atheroprotective functions of apoprotein A-containing high-density lipoprotein (HDL) particles are poorly understood. The association between lipoproteins and plaque components by coronary computed tomography angiography (CTA) and intravascular ultrasound with radiofrequency backscatter (IVUS/VH) has not been evaluated. METHODS AND RESULTS: Quantitative, 3-dimensional plaque measurements were performed in 60 patients with CTA and IVUS/VH. Apoproteins, lipids, and HDL subpopulations were measured with 2-dimensional (2D) gel electrophoresis, and correlation was assessed with univariate and multivariable models. ApoB particles were associated with a higher proportion of noncalcified plaque (NCP) and a lower proportion of calcified plaque (small, dense low-density lipoprotein cholesterol and high-density NCP: r=0.3, P=0.03; triglycerides and low-density NCP: r=0.34, P=0.01). Smaller, dense, lipid-poor HDL particles were associated with a shift from calcified plaque to NCP on CTA (α3-HDL% and low-density NCP: r=0.32, P=0.02) and with larger plaque volume on IVUS/VH (α4-HDL%: r=0.41, P=0.01; α3-HDL%: r=0.37, P=0.03), because of larger dense calcium (α4-HDL%: r=0.37, P=0.03), larger fibrous tissue (α4-HDL%: r=0.34, P=0.04), and larger necrotic core (α4-HDL%: r=0.46, P<0.01; α3-HDL%: r=0.37, P=0.03). Larger lipid-rich HDL particles were associated with less low-density NCP on CTA (α2-HDL%: r=-0.34, P=0.02; α1-HDL%: r=-0.28, P=0.05), with smaller plaque volume on IVUS/VH (pre-α2-HDL: r=-0.33, P=0.05; α1-HDL%: r=-0.41, P=0.01; pre-α2-HDL: r=-0.33, P=0.05) and with less necrotic core (α1-HDL: r=-0.42, P<0.01; pre-α2-HDL: r=-0.38, P=0.02; α2-HDL: r=-0.35, P=0.03; pre-α1-HDL: r=-0.34, P=0.04). Pre-ß2-HDL was associated with less calcification and less stenosis by both modalities. CONCLUSIONS: ApoB and small HDL particles are associated with larger plaque burden and more noncalcified plaque, whereas larger HDL and pre-ß2-HDL particles are associated with plaque burden and less noncalcified plaque by both CTA and IVUS/VH.

Prospective validation that vulnerable plaque associated with major adverse outcomes have larger plaque volume, less dense calcium, and more non-calcified plaque by quantitative, three-dimensional measurements using intravascular ultrasound with radiofrequency backscatter analysis : results from the ATLANTA I Study.

Whether quantitative, two-dimensional, and three-dimensional plaque measurements by intravascular ultrasound with radiofrequency backscatter (IVUS/VH) are different between intermediate lesions with or without major adverse cardiovascular events (MACE) is unknown. IVUS/VH-derived parameters were compared in 60 patients with an intermediate coronary lesion (40-70 %) between lesions that did or did not result in MACE over 12 months. IVUS/VH measurements were done at the site of the minimal lumen area (MLA) and on a per-plaque basis, defined by 40 % plaque burden. Pre-specified, adjudicated MACE events occurred in 5 of 60 patients (8.3 %). MACE lesions had larger plaque burden (65 % vs. 53 %, p = 0.004), less dense calcium (6.6 % vs. 14.7 %, p = 0.05), and more non-calcified plaque, mostly fibrofatty kind (17.6 % vs. 10 %, p = 0.02). Intermediate coronary lesions associated with MACE at 12 months have more plaque, less dense calcium, and more non-calcified plaque, particularly fibrofatty tissue by IVUS/VH.