P2720Diagnostic accuracy of Quantitative Flow Ratio (QFR) and Vessel Fractional Flow Reserve (vFFR) compared to Fractional Flow Reserve (FFR) based on 7.5 frames/second coronary angiography

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
C Y Jin ◽  
A Ramasamy ◽  
C V Bourantas ◽  
H Safi ◽  
Y Kilic ◽  
...  

Abstract Background Fractional flow reserve (FFR) is the gold standard for the physiological assessment of intermediate coronary artery lesions. Recently, several novel methods for computation of FFR based on 3-dimensional quantitative coronary angiography have been developed. These techniques allow analyses to be performed retrospectively and do not require induction of hyperaemia. The development and validation of these techniques are based on good quality coronary angiography with high frames per second (15 fps) acquisition. The diagnostic accuracy of Quantitative Flow Ratio (QFR) and Vessel Fractional Flow Reserve (vFFR) in real world “radiation-save mode” coronary angiography has not been studied. Purpose To validate the accuracy of QFR and vFFR compared to FFR based on a series of coronary angiography acquired at 7.5 fps. Methods We retrospectively analyzed 134 vessels (102 patients) with intermediate coronary artery stenosis (30–90%) in whom an FFR measurement had been performed. All the coronary angiography were acquired at 7.5 fps. 33 vessels (20 patients) were excluded from the study due to unsuitable coronary anatomy, invalid FFR measurements, poor image quality and lack of 2 projections ≥25° apart. A total of 101 vessels (82 patients) were included in the final analysis. Contrast-QFR (cQFR), fixed-QFR (fQFR) and vFFR analysis were performed in these vessels by two independent trained experts blinded to the FFR readings. FFR measurements at hyperaemic steady state was taken as the gold standard reference. Results Good intra- and inter-observer reliability was noted for fQFR, cQFR and vFFR analysis (intra-observer mean difference for fQFR: 0.016±0.060, p=0.066; cQFR: 0.009±0.053, p=0.230; vFFR: 0.008±0.040, p=0.175; inter-observer mean difference for fQFR: 0.001±0.036, p=0.847; cQFR: −0.001±0.049; p=0.910, vFFR: −0.005±0.037, p=0.393). fQFR and cQFR showed good correlation with FFR (r=0.694, p<0.001 and r=0.674, p<0.001, respectively) while vFFR showed moderate correlation with FFR (r=0.388, p<0.001). Similarly, fQFR and cQFR showed good accuracy for the detection of functionally significant coronary stenosis (fQFR AUC 0.882 (95% CI 0.803–0.938) and cQFR AUC 0.886 (95% CI 0.807–0.940)) while vFFR showed moderate accuracy with AUC 0.719 (95% CI 0.621–0.804). For identifying functionally significant stenosis (FFR ≤0.80), the overall diagnostic accuracy were 81.2%, 85.2%, 75.3% for fQFR, cQFR and vFFR, repectively. The sensitivity and specificity were 72.7%, 89.9% (fQFR); 83.5%, 31.8% (cQFR) and 68.2%, 87.3% (vFFR). Conclusion Functional assessment of intermediate coronary stenosis based on 7.5 fps angiography-derived computational modelling is feasible. Our study shows that fQFR and cQFR have a better diagnostic accuracy for detecting functionally significant coronary stenosis compared to vFFR. At the lower radiation-save mode 7.5 fps angiography, cQFR does not appear to provide additional diagnostic accuracy compared to fQFR.

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Ruitao Zhang ◽  
Jianwei Zhang ◽  
Lijun Guo

Background. Use of the fractional flow reserve (FFR) technique is recommended to evaluate coronary stenosis severity and guide revascularization. However, its high cost, time to administer, and the side effects of adenosine reduce its clinical utility. Two novel adenosine-free indices, contrast-FFR (cFFR) and quantitative flow ratio (QFR), can simplify the functional evaluation of coronary stenosis. This study aimed to analyze the diagnostic performance of cFFR and QFR using FFR as a reference index. Methods. We conducted a systematic review and meta-analysis of observational studies in which cFFR or QFR was compared to FFR. A bivariate model was applied to pool diagnostic parameters. Cochran’s Q test and the I2 index were used to assess heterogeneity and identify the potential source of heterogeneity by metaregression and sensitivity analysis. Results. Overall, 2220 and 3000 coronary lesions from 20 studies were evaluated by cFFR and QFR, respectively. The pooled sensitivity and specificity were 0.87 (95% CI: 0.81, 0.91) and 0.92 (95% CI: 0.88, 0.94) for cFFR and 0.87 (95% CI: 0.82, 0.91) and 0.91 (95% CI: 0.87, 0.93) for QFR, respectively. No statistical significance of sensitivity and specificity for cFFR and QFR were observed in the bivariate analysis (P=0.8406 and 0.4397, resp.). The area under summary receiver-operating curve of cFFR and QFR was 0.95 (95% CI: 0.93, 0.97) for cFFR and 0.95 (95% CI: 0.93, 0.97). Conclusion. Both cFFR and QFR have good diagnostic performance in detecting functional severity of coronary arteries and showed similar diagnostic parameters.


2018 ◽  
Vol 20 (11) ◽  
pp. 1231-1238 ◽  
Author(s):  
Jeff M Smit ◽  
Gerhard Koning ◽  
Alexander R van Rosendael ◽  
Mohammed El Mahdiui ◽  
Bart J Mertens ◽  
...  

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.


2020 ◽  
Vol 26 (6) ◽  
pp. 793-795
Author(s):  
Paweł Kleczyński ◽  
Artur Dziewierz ◽  
Lukasz Rzeszutko ◽  
Dariusz Dudek ◽  
Jacek Legutko

2021 ◽  
Vol 8 ◽  
Author(s):  
Menghuan Li ◽  
Iokfai Cheang ◽  
Yuan He ◽  
Shengen Liao ◽  
Hui Wang ◽  
...  

Objective: Intravascular ultrasound (IVUS) parameters, for example, minimal lumen area (MLA) and area stenosis (AS), poorly identified functional intermediate coronary stenosis (ICS). For detecting functional ICS defined by coronary angiography-derived fractional flow reserve (caFFR), our study aims to determine whether IVUS parameters integrated with lesion length (LL) by three-dimensional quantitative coronary analysis (3D-QCA) could improve diagnostic value.Methods: A total of 111 patients with 122 ICS lesions in the non-left main artery were enrolled. MLA and AS were calculated in all lesions by IVUS. Diameter stenosis (DS%) and LL were measured by 3D-QCA. caFFR was computed by the proprietary fluid dynamic algorithm, a caFFR ≤ 0.8 was considered as functional stenosis. Receiver-operating curve analyses were used to compare the diagnostic accuracy among indices to predict functional stenoses.Results: Mean caFFR values in all lesions were 0.86 ± 0.09. Lesions with caFFR ≤ 0.8 showed lower MLA and higher AS (MLA: 3.3 ± 0.8 vs. 4.1 ± 1.2, P = 0.002; AS: 71.3 ± 9.6% vs. 63.5 ± 1.3%, P = 0.007). DS% and LL were more severe in lesions with caFFR ≤ 0.8 (DS%: 45.5 ± 9.6% vs. 35.5 ± 8.2%, P &lt; 0.001; LL: 31.6 ± 12.9 vs. 21.0 ± 12.8, P &lt; 0.001). caFFR were correlated with MLA, AS, and LL (MLA: r = 0.36, P &lt; 0.001; AS: r = −0.36, P &lt; 0.001; LL: r = −0.41, P &lt; 0.001). Moreover, a multiple linear regression analysis demonstrated that MLA (β = 0.218, P = 0.013), AS (β = −0.197, P = 0.029), and LL (β = −0.306, P &gt; 0.001) contributed significantly to the variation in caFFR. The best cutoff value of MLA, AS, and LL for predicting caFFR ≤ 0.8 were 3.6 mm2, 73%, and 26 mm, with area under the curve (AUC) of 0.714, 0.688, and 0.767, respectively. Combined with MLA, AS, and LL for identifying functional ICS, the accuracy was the highest among study methods (AUC: 0.845, P &lt; 0.001), and was significantly higher than each single method (All P &lt; 0.05).Conclusion: Lesion length can improve the diagnostic accuracy of IVUS-derived parameters for detecting functional ICS.


Open Heart ◽  
2020 ◽  
Vol 7 (1) ◽  
pp. e001179 ◽  
Author(s):  
Yoshinori Kanno ◽  
Masahiro Hoshino ◽  
Rikuta Hamaya ◽  
Tomoyo Sugiyama ◽  
Yoshihisa Kanaji ◽  
...  

BackgroundMeasurement of the contrast-flow quantitative flow ratio (cQFR) is a novel method for rapid computational estimation of fractional flow reserve (FFR). Discordance between FFR and cQFR has not been completely characterised.MethodsWe performed a post-hoc analysis of 504 vessels with angiographically intermediate stenosis in 504 patients who underwent measurement of FFR, coronary flow reserve (CFR), the index of microcirculatory resistance (IMR) and Duke jeopardy score.ResultsIn total, 396 (78.6%) and 108 (21.4%) lesions showed concordant and discordant FFR and cQFR functional classifications, respectively. Among lesions with a reduced FFR (FFR+), those with a preserved cQFR (cQFR−) showed significantly lower IMR, shorter mean transit time (Tmn), shorter lesion length (all, p<0.01) and similar CFR and Duke jeopardy scores compared with lesions showing a reduced cQFR (cQFR+). Furthermore, lesions with FFR+ and cQFR− had significantly lower IMR and shorter Tmn compared with lesions showing a preserved FFR (FFR−) and cQFR+. Of note, in cQFR+ lesions, higher IMR lesions were associated with decreased diagnostic accuracy (high-IMR; 63.0% and low-IMR; 75.8%, p<0.01). In contrast, in cQFR− lesions, lower IMR lesions was associated with decreased diagnostic accuracy (high-IMR group; 96.8% and low-IMR group; 80.0%, p<0.01). Notably, in total, 31 territories (6.2%; ‘jump out’ group) had an FFR above the upper limit of the grey zone (>0.80) and a cQFR below the lower limit (≤0.75). In contrast, five territories (1.0%; ‘jump in’ group) exhibited opposite results (FFR of ≤0.75 and cQFR of >0.80). The ‘jump out’ territories showed significantly higher IMR values than ‘jump in’ territories (p<0.01).ConclusionsFFR− with cQFR+ is associated with increased microvascular resistance, and FFR+ with cQFR− showed preservation of microvascular function with high coronary flow. Microvascular function affected diagnostic performance of cQFR in relation to functional stenosis significance.


2021 ◽  
Vol 25 (56) ◽  
pp. 1-230
Author(s):  
Ana Duarte ◽  
Alexis Llewellyn ◽  
Ruth Walker ◽  
Laetitia Schmitt ◽  
Kath Wright ◽  
...  

Background QAngio® XA 3D/QFR® (three-dimensional/quantitative flow ratio) imaging software (Medis Medical Imaging Systems BV, Leiden, the Netherlands) and CAAS® vFFR® (vessel fractional flow reserve) imaging software (Pie Medical Imaging BV, Maastricht, the Netherlands) are non-invasive technologies to assess the functional significance of coronary stenoses, which can be alternatives to invasive fractional flow reserve assessment. Objectives The objectives were to determine the clinical effectiveness and cost-effectiveness of QAngio XA 3D/QFR and CAAS vFFR. Methods We performed a systematic review of all evidence on QAngio XA 3D/QFR and CAAS vFFR, including diagnostic accuracy, clinical effectiveness, implementation and economic analyses. We searched MEDLINE and other databases to January 2020 for studies where either technology was used and compared with fractional flow reserve in patients with intermediate stenosis. The risk of bias was assessed with quality assessment of diagnostic accuracy studies. Meta-analyses of diagnostic accuracy were performed. Clinical and implementation outcomes were synthesised narratively. A simulation study investigated the clinical impact of using QAngio XA 3D/QFR. We developed a de novo decision-analytic model to estimate the cost-effectiveness of QAngio XA 3D/QFR and CAAS vFFR relative to invasive fractional flow reserve or invasive coronary angiography alone. Scenario analyses were undertaken to explore the robustness of the results to variation in the sources of data used to populate the model and alternative assumptions. Results Thirty-nine studies (5440 patients) of QAngio XA 3D/QFR and three studies (500 patients) of CAAS vFFR were included. QAngio XA 3D/QFR had good diagnostic accuracy to predict functionally significant fractional flow reserve (≤ 0.80 cut-off point); contrast-flow quantitative flow ratio had a sensitivity of 85% (95% confidence interval 78% to 90%) and a specificity of 91% (95% confidence interval 85% to 95%). A total of 95% of quantitative flow ratio measurements were within 0.14 of the fractional flow reserve. Data on the diagnostic accuracy of CAAS vFFR were limited and a full meta-analysis was not feasible. There were very few data on clinical and implementation outcomes. The simulation found that quantitative flow ratio slightly increased the revascularisation rate when compared with fractional flow reserve, from 40.2% to 42.0%. Quantitative flow ratio and fractional flow reserve resulted in similar numbers of subsequent coronary events. The base-case cost-effectiveness results showed that the test strategy with the highest net benefit was invasive coronary angiography with confirmatory fractional flow reserve. The next best strategies were QAngio XA 3D/QFR and CAAS vFFR (without fractional flow reserve). However, the difference in net benefit between this best strategy and the next best was small, ranging from 0.007 to 0.012 quality-adjusted life-years (or equivalently £140–240) per patient diagnosed at a cost-effectiveness threshold of £20,000 per quality-adjusted life-year. Limitations Diagnostic accuracy evidence on CAAS vFFR, and evidence on the clinical impact of QAngio XA 3D/QFR, were limited. Conclusions Quantitative flow ratio as measured by QAngio XA 3D/QFR has good agreement and diagnostic accuracy compared with fractional flow reserve and is preferable to standard invasive coronary angiography alone. It appears to have very similar cost-effectiveness to fractional flow reserve and, therefore, pending further evidence on general clinical benefits and specific subgroups, could be a reasonable alternative. The clinical effectiveness and cost-effectiveness of CAAS vFFR are uncertain. Randomised controlled trial evidence evaluating the effect of quantitative flow ratio on clinical and patient-centred outcomes is needed. Future work Studies are required to assess the diagnostic accuracy and clinical feasibility of CAAS vFFR. Large ongoing randomised trials will hopefully inform the clinical value of QAngio XA 3D/QFR. Study registration This study is registered as PROSPERO CRD42019154575. Funding This project was funded by the National Institute for Health Research (NIHR) Evidence Synthesis programme and will be published in full in Health Technology Assessment; Vol. 25, No. 56. See the NIHR Journals Library website for further project information.


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