Residual Quantitative Flow Ratio to Estimate Post‐Percutaneous Coronary Intervention Fractional Flow Reserve

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, p < 0.001 ). A significant correlation and agreement were observed between residual QFR and post-PCI FFR (R = 0.56 and intraclass correlation coefficient = 0.47, p < 0.001 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.

Download Full-text

Referral of patients for fractional flow reserve using quantitative flow ratio

European Heart Journal - Cardiovascular Imaging ◽

10.1093/ehjci/jey187 ◽

2018 ◽

Vol 20 (11) ◽

pp. 1231-1238 ◽

Cited By ~ 5

Author(s):

Jeff M Smit ◽

Gerhard Koning ◽

Alexander R van Rosendael ◽

Mohammed El Mahdiui ◽

Bart J Mertens ◽

...

Keyword(s):

Coronary Angiography ◽

Fractional Flow Reserve ◽

Invasive Coronary Angiography ◽

Quantitative Coronary Angiography ◽

Coronary Intervention ◽

Flow Ratio ◽

Fractional Flow ◽

Flow Reserve ◽

Quantitative Flow Ratio ◽

Quantitative Flow

Abstract Aims Quantitative flow ratio (QFR) is a recently developed technique to calculate fractional flow reserve (FFR) based on 3D quantitative coronary angiography and computational fluid dynamics, obviating the need for a pressure-wire and hyperaemia induction. QFR might be used to guide patient selection for FFR and subsequent percutaneous coronary intervention (PCI) referral in hospitals not capable to perform FFR and PCI. We aimed to investigate the feasibility to use QFR to appropriately select patients for FFR referral. Methods and results Patients who underwent invasive coronary angiography in a hospital where FFR and PCI could not be performed and were referred to our hospital for invasive FFR measurement, were included. Angiogram images from the referring hospitals were retrospectively collected for QFR analysis. Based on QFR cut-off values of 0.77 and 0.86, our patient cohort was reclassified to ‘no referral’ (QFR ≥0.86), referral for ‘FFR’ (QFR 0.78–0.85), or ‘direct PCI’ (QFR ≤0.77). In total, 290 patients were included. Overall accuracy of QFR to detect an invasive FFR of ≤0.80 was 86%. Based on a QFR cut-off value of 0.86, a 50% reduction in patient referral for FFR could be obtained, while only 5% of these patients had an invasive FFR of ≤0.80 (thus, these patients were incorrectly reclassified to the ‘no referral’ group). Furthermore, 22% of the patients that still need to be referred could undergo direct PCI, based on a QFR cut-off value of 0.77. Conclusion QFR is feasible to use for the selection of patients for FFR referral.

Download Full-text

Residual quantitative flow ratio to estimate post-intervention fractional flow reserve

European Heart Journal ◽

10.1093/eurheartj/ehab724.2078 ◽

2021 ◽

Vol 42 (Supplement_1) ◽

Author(s):

P A Van Diemen ◽

R W De Winter ◽

S P Schumacher ◽

M J Bom ◽

R S Driessen ◽

...

Keyword(s):

Correlation Coefficient ◽

Fractional Flow Reserve ◽

Predictive Value ◽

Intraclass Correlation ◽

Flow Ratio ◽

Moderate Correlation ◽

Fractional Flow ◽

Flow Reserve ◽

Quantitative Flow Ratio ◽

Quantitative Flow

Abstract Objective To assess the performance of residual quantitative flow ratio (QFR) to estimate post percutaneous coronary intervention (PCI) fractional flow reserve (FFR). Background QFR computes FFR based on invasive coronary angiography (ICA) images. Residual QFR is a novel tool that assesses the functional outcome of an intervention by estimating post-PCI FFR. Methods Residual QFR analyses, using pre-PCI ICA images, were attempted in 159 vessels with post-PCI FFR measurements. QFR lesion location was matched with the treated segment to allow virtual removal of the lesion similar to the performed PCI and computation of residual QFR (Picture 1: case example of residual QFR analysis). 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 interquartile range (IQR): 0.91–0.99 vs. 0.91 IQR: 0.86–0.96, p<0.001). A moderate correlation and agreement was observed between residual QFR and post-PCI FFR (Spearman correlation coefficient=0.56 and Intraclass correlation coefficient=0.47, p<0.001 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 determining a suboptimal 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. Overall, residual QFR had an accuracy of 74% (95% CI: 66–82%) and an area under the receiver operating characteristic curve of 0.79 for assessing a post PCI FFR <0.90. Conclusion A moderate correlation and agreement between residual QFR and post-PCI FFR was observed. Residual QFR ≥0.90 does not necessarily commensurate with an optimal PCI result. However, residual QFR <0.90 is a good indicator of a post-PCI FFR <0.90 and might therefore be utilized to determine PCI location in order to obtain a satisfactory PCI result (Picture 2: central illustration). FUNDunding Acknowledgement Type of funding sources: None. Case example of residual QFR analysis Central illustration

Download Full-text