Department of Information Engineering, Northwestern Polytechnical University, Xi'an, Shaanxi, People's Republic of China.
Department of Radiology, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, People's Republic of China.
Eur Radiol. 2020 Aug;30(8):4347-4355. doi: 10.1007/s00330-020-06821-w. Epub 2020 Apr 2.
Coronary CT angiography (cCTA) has been used to non-invasively assess both the anatomical and hemodynamic significance of coronary stenosis. The current study investigated a new CFD-based method of evaluating pressure-flow curves across a stenosis to further enhance the diagnostic value of cCTA imaging.
Fifty-eight patients who underwent both cCTA imaging and invasive coronary angiography (ICA) with fractional flow reserve (FFR) within 2 weeks were enrolled. The pressure-flow curve-derived parameters, viscous friction (VF) and expansion loss (EL), were compared with conventional cCTA parameters including percent area stenosis (AS) and minimum lumen area (MLA) by receiver operating characteristic (ROC) curve analysis. FFR ≤ 0.80 was used to indicate ischemia-causing stenosis. Correlations between FFR and other measurements were calculated by Spearman's rank correlation coefficient (rho).
Sixty-eight stenoses from 58 patients were analyzed. VF, EL, and AS were significantly larger in the group of FFR ≤ 0.8 while smaller MLA values were observed. The ROC-AUC of VF (0.91, 95% CI 0.81-0.96) was better than that of AS (change in AUC (ΔAUC) 0.27, p < 0.05) and MLA (ΔAUC 0.17, p < 0.05), and ROC-AUC of EL (0.90, 95%CI 0.80-0.96) was also better than that of AS (ΔAUC 0.26, p < 0.05) and MLA (ΔAUC 0.16, p < 0.05). FFR values correlated well with VF (rho = - 0.74 (95% CI - 0.83 to - 0.61, p < 0.0001) and EL (rho = - 0.74 (95% CI - 0.83 to - 0.61, p < 0.0001).
Pressure-flow curve-derived parameters enhance the diagnostic value of cCTA examination.
• Pressure-flow curve derived from cCTA can assess coronary lesion severity. • VF and EL are superior to cCTA alone for indicating ischemic lesions. • Pressure-flow curve derived from cCTA may assist in clinical decision-making.
冠状动脉 CT 血管造影（cCTA）已被用于无创评估冠状动脉狭窄的解剖学和血流动力学意义。本研究旨在探讨一种新的基于计算流体动力学（CFD）的方法来评估狭窄处的压力-流量曲线，以进一步提高 cCTA 成像的诊断价值。
本研究纳入了 58 例在 2 周内同时接受 cCTA 成像和有血流储备分数（FFR）的冠状动脉造影（ICA）的患者。通过受试者工作特征（ROC）曲线分析，比较压力-流量曲线衍生参数粘性摩擦（VF）和扩张损失（EL）与传统 cCTA 参数（狭窄百分比（AS）和最小管腔面积（MLA））的诊断价值。FFR≤0.8 用于指示导致缺血的狭窄。采用 Spearman 秩相关系数（rho）计算 FFR 与其他测量值之间的相关性。
对 58 例患者的 68 处狭窄进行了分析。FFR≤0.8 组的 VF、EL 和 AS 显著增大，而 MLA 值较小。VF 的 ROC-AUC（0.91，95%CI 0.81-0.96）优于 AS（AUC 变化（ΔAUC）0.27，p<0.05）和 MLA（ΔAUC 0.17，p<0.05），EL 的 ROC-AUC（0.90，95%CI 0.80-0.96）也优于 AS（ΔAUC 0.26，p<0.05）和 MLA（ΔAUC 0.16，p<0.05）。FFR 值与 VF（rho=-0.74（95%CI-0.83 至-0.61，p<0.0001）和 EL（rho=-0.74（95%CI-0.83 至-0.61，p<0.0001）相关性良好。
压力-流量曲线衍生参数可提高 cCTA 检查的诊断价值。
• cCTA 衍生的压力-流量曲线可评估冠状动脉病变严重程度。• VF 和 EL 比单独的 cCTA 更能提示缺血性病变。• cCTA 衍生的压力-流量曲线有助于临床决策。
