Objectives. Quantitative flow ratio (QFR) computes fractional flow reserve (FFR) based on invasive coronary angiography (ICA). Residual QFR estimates post‐percutaneous coronary intervention (PCI) FFR. This study sought to assess the relationship of residual QFR with post-PCI FFR. Methods. Residual QFR analysis, using pre-PCI ICA, was attempted in 159 vessels with post-PCI FFR. QFR lesion location was matched with the PCI location to simulate the performed intervention and allow computation of residual QFR. A post-PCI FFR < 0.90 was used to define a suboptimal PCI result. Results. Residual QFR computation was successful in 128 (81%) vessels. Median residual QFR was higher than post-PCI FFR (0.96 Q1–Q3: 0.91–0.99 vs. 0.91 Q1–Q3: 0.86–0.96, ). A significant correlation and agreement were observed between residual QFR and post-PCI FFR (R = 0.56 and intraclass correlation coefficient = 0.47, for both). Following PCI, an FFR < 0.90 was observed in 54 (42%) vessels. Specificity, positive predictive value, sensitivity, and negative predictive value of residual QFR for assessment of the PCI result were 96% (95% confidence interval (CI): 87–99%), 89% (95% CI: 72–96%), 44% (95% CI: 31–59%), and 70% (95% CI: 65–75%), respectively. Residual QFR had an accuracy of 74% (95% CI: 66–82%) and an area under the receiver operating characteristic curve of 0.79 (95% CI: 0.71–0.86). Conclusions. A significant correlation and agreement between residual QFR and post-PCI FFR were observed. Residual QFR ≥ 0.90 did not necessarily commensurate with a satisfactory PCI (post-PCI FFR ≥ 0.90). In contrast, residual QFR exhibited a high specificity for prediction of a suboptimal PCI result.

中文翻译：

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残余定量流量比估计经皮冠状动脉介入治疗后分数流量储备

目标。定量流量比 (QFR) 基于侵入性冠状动脉造影 (ICA) 计算流量储备分数 (FFR)。残余 QFR 估计经皮冠状动脉介入治疗 (PCI) 后 FFR。本研究旨在评估残余 QFR 与 PCI 后 FFR 的关系。方法。使用 PCI 前 ICA 对 159 支 PCI 后 FFR 血管进行了残余 QFR 分析。QFR 病变位置与 PCI 位置相匹配，以模拟执行的干预并允许计算残余 QFR。PCI 后 FFR < 0.90 用于定义次优 PCI 结果。结果。残余 QFR 计算在 128 支 (81%) 血管中成功。中位残余 QFR 高于 PCI 后 FFR（0.96 Q1–Q3：0.91–0.99 vs. 0.91 Q1–Q3：0.86–0.96，）。在残余 QFR 和 PCI 后 FFR 之间观察到显着的相关性和一致性（ R  = 0.56，组内相关系数 = 0.47，对彼此而言）。PCI 后，在 54 支 (42%) 血管中观察到 FFR < 0.90。残余 QFR 用于评估 PCI 结果的特异性、阳性预测值、敏感性和阴性预测值分别为 96%（95% 置信区间 (CI)：87-99%）、89%（95% CI：72-96% )、44% (95% CI: 31–59%) 和 70% (95% CI: 65–75%)。残余 QFR 的准确度为 74%（95% CI：66-82%），受试者工作特征曲线下面积为 0.79（95% CI：0.71-0.86）。结论。观察到残余 QFR 和 PCI 后 FFR 之间的显着相关性和一致性。残余 QFR ≥ 0.90 不一定与令人满意的 PCI 相称（PCI 后 FFR ≥ 0.90）。相比之下，残余 QFR 表现出对次优 PCI 结果预测的高度特异性。