Cardiovascular Division, Brigham & Women's Hospital/Harvard Medical School, Boston, MA, USA.
Department of Mechanical and Industrial Engineering, Northeastern University, Boston, MA, USA.
J Cardiovasc Comput Tomogr. 2023 May-Jun;17(3):201-210. doi: 10.1016/j.jcct.2023.03.009. Epub 2023 Apr 17.
Intravascular ultrasound (IVUS) studies have shown that biomechanical variables, particularly endothelial shear stress (ESS), add synergistic prognostic insight when combined with anatomic high-risk plaque features. Non-invasive risk assessment of coronary plaques with coronary computed tomography angiography (CCTA) would be helpful to enable broad population risk-screening.
To compare the accuracy of ESS computation of local ESS metrics by CCTA vs IVUS imaging.
We analyzed 59 patients from a registry of patients who underwent both IVUS and CCTA for suspected CAD. CCTA images were acquired using either a 64- or 256-slice scanner. Lumen, vessel, and plaque areas were segmented from both IVUS and CCTA (59 arteries, 686 3-mm segments). Images were co-registered and used to generate a 3-D arterial reconstruction, and local ESS distribution was assessed by computational fluid dynamics (CFD) and reported in consecutive 3-mm segments.
Anatomical plaque characteristics (vessel, lumen, plaque area and minimal luminal area [MLA] per artery) were correlated when measured with IVUS and CCTA: 12.7 ± 4.3 vs 10.7 ± 4.5 mm, r = 0.63; 6.8 ± 2.7 vs 5.6 ± 2.7 mm, r = 0.43; 5.9 ± 2.9 vs 5.1 ± 3.2 mm, r = 0.52; 4.5 ± 1.3 vs 4.1 ± 1.5 mm, r = 0.67 respectively. ESS metrics of local minimal, maximal, and average ESS were also moderately correlated when measured with IVUS and CCTA (2.0 ± 1.4 vs 2.5 ± 2.6 Pa r = 0.28; 3.3 ± 1.6 vs 4.2 ± 3.6 Pa, r = 0.42; 2.6 ± 1.5 vs 3.3 ± 3.0 Pa, r = 0.35, respectively). CCTA-based computation accurately identified the spatial localization of local ESS heterogeneity compared to IVUS, with Bland-Altman analyses indicating that the absolute ESS differences between the two CCTA methods were pathobiologically minor.
Local ESS evaluation by CCTA is possible and similar to IVUS; and is useful for identifying local flow patterns that are relevant to plaque development, progression, and destabilization.
血管内超声（IVUS）研究表明，生物力学变量，尤其是内皮剪切应力（ESS），与解剖学高危斑块特征相结合，提供了协同的预后见解。用冠状动脉计算机断层扫描血管造影（CCTA）对冠状动脉斑块进行非侵入性风险评估将有助于进行广泛的人群风险筛查。
比较 CCTA 与 IVUS 成像计算局部 ESS 指标的 ESS 计算的准确性。
我们对接受 IVUS 和 CCTA 检查疑似 CAD 的 59 例患者的登记处进行了分析。CCTA 图像使用 64 或 256 层扫描仪采集。从 IVUS 和 CCTA（59 个动脉，686 个 3mm 节段）中分割出管腔、血管和斑块区域。对图像进行配准，并生成 3-D 动脉重建，通过计算流体动力学（CFD）评估局部 ESS 分布，并在连续的 3mm 节段中报告。
当用 IVUS 和 CCTA 测量时，解剖斑块特征（血管、管腔、斑块面积和每个动脉的最小管腔面积 [MLA]）相关：12.7±4.3 vs 10.7±4.5mm，r=0.63；6.8±2.7 vs 5.6±2.7mm，r=0.43；5.9±2.9 vs 5.1±3.2mm，r=0.52；4.5±1.3 vs 4.1±1.5mm，r=0.67。当用 IVUS 和 CCTA 测量时，局部最小、最大和平均 ESS 指标也呈中度相关（2.0±1.4 vs 2.5±2.6Pa，r=0.28；3.3±1.6 vs 4.2±3.6Pa，r=0.42；2.6±1.5 vs 3.3±3.0Pa，r=0.35）。与 IVUS 相比，CCTA 基于计算的局部 ESS 异质性的空间定位准确，Bland-Altman 分析表明，两种 CCTA 方法之间的绝对 ESS 差异在病理生物学上很小。
CCTA 能够进行局部 ESS 评估，与 IVUS 相似；对于识别与斑块发展、进展和不稳定相关的局部血流模式是有用的。
