scholarly journals A validated predictive model of coronary fractional flow reserve

2011 ◽  
Vol 9 (71) ◽  
pp. 1325-1338 ◽  
Author(s):  
Yunlong Huo ◽  
Mark Svendsen ◽  
Jenny Susana Choy ◽  
Z.-D. Zhang ◽  
Ghassan S. Kassab
Keyword(s):  
Analytical Model ◽  
Fractional Flow Reserve ◽  
Coronary Stenosis ◽  
Coronary Flow ◽  
Energy Losses ◽  
Fractional Flow ◽  
Conservation Of Energy ◽  
Flow Reserve

Myocardial fractional flow reserve (FFR), an important index of coronary stenosis, is measured by a pressure sensor guidewire. The determination of FFR, only based on the dimensions (lumen diameters and length) of stenosis and hyperaemic coronary flow with no other ad hoc parameters, is currently not possible. We propose an analytical model derived from conservation of energy, which considers various energy losses along the length of a stenosis, i.e. convective and diffusive energy losses as well as energy loss due to sudden constriction and expansion in lumen area. In vitro (constrictions were created in isolated arteries using symmetric and asymmetric tubes as well as an inflatable occluder cuff) and in vivo (constrictions were induced in coronary arteries of eight swine by an occluder cuff) experiments were used to validate the proposed analytical model. The proposed model agreed well with the experimental measurements. A least-squares fit showed a linear relation as (Δ p or FFR) experiment = a (Δ p or FFR) theory + b , where a and b were 1.08 and −1.15 mmHg ( r 2 = 0.99) for in vitro Δ p , 0.96 and 1.79 mmHg ( r 2 = 0.75) for in vivo Δ p , and 0.85 and 0.1 ( r 2 = 0.7) for FFR. Flow pulsatility and stenosis shape (e.g. eccentricity, exit angle divergence, etc.) had a negligible effect on myocardial FFR, while the entrance effect in a coronary stenosis was found to contribute significantly to the pressure drop. We present a physics-based experimentally validated analytical model of coronary stenosis, which allows prediction of FFR based on stenosis dimensions and hyperaemic coronary flow with no empirical parameters.

scholarly journals The reasons why fractional flow reserve and instantaneous wave-free ratio are similar using wave separation analysis

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Soohong Min ◽  
Gwansuk Kang ◽  
Dong-Guk Paeng ◽  
Joon Hyouk Choi
Keyword(s):  
Fractional Flow Reserve ◽  
Circulation System ◽  
Fractional Flow ◽  
Wave Separation ◽  
Flow Reserve ◽  
Stenosis Severity ◽  
The Relationship ◽  
Wedge Pressure

Abstract Background and objectives Fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) are the two most commonly used coronary indices of physiological stenosis severity based on pressure. To minimize the effect of wedge pressure (Pwedge), FFR is measured during hyperemia conditions, and iFR is calculated as the ratio of distal and aortic pressures (Pd/Pa) in the wave-free period. The goal of this study was to predict Pwedge using the backward wave (Pback) through wave separation analysis (WSA) and to reflect the effect of Pwedge on FFR and iFR to identify the relationship between the two indices. Methods An in vitro circulation system was constructed to calculate Pwedge. The measurements were performed in cases with stenosis percentages of 48, 71, and 88% and with hydrostatic pressures of 10 and 30 mmHg. Then, the correlation between Pback by WSA and Pwedge was calculated. In vivo coronary flow and pressure were simultaneously measured for 11 vessels in all patients. The FFR and iFR values were reconstructed as the ratios of forward wave at distal and proximal sites during hyperemia and at rest, respectively. Results Based on the in vitro results, the correlation between Pback and Pwedge was high (r = 0.990, p < 0.0001). In vivo results showed high correlations between FFR and reconstructed FFR (r = 0.992, p < 0.001) and between iFR and reconstructed iFR (r = 0.930, p < 0.001). Conclusions Reconstructed FFR and iFR were in good agreement with conventional FFR and iFR. FFR and iFR can be expressed as the variation of trans-stenotic forward pressure, indicating that the two values are inferred from the same formula under different conditions.

scholarly journals Non-randomized comparison between revascularization and deferral for intermediate coronary stenosis with abnormal fractional flow reserve and preserved coronary flow reserve

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Doosup Shin ◽  
Joo Myung Lee ◽  
Seung Hun Lee ◽  
Doyeon Hwang ◽  
Ki Hong Choi ◽  
...  
Keyword(s):  
Coronary Flow Reserve ◽  
Fractional Flow Reserve ◽  
International Collaboration ◽  
Coronary Stenosis ◽  
Coronary Flow ◽  
Target Vessel ◽  
Fractional Flow ◽  
Patient Level ◽  
Flow Reserve ◽  
Significant Difference

AbstractLimited data are available regarding comparative prognosis after percutaneous coronary intervention (PCI) versus deferral of revascularization in patients with intermediate stenosis with abnormal fractional flow reserve (FFR) but preserved coronary flow reserve (CFR). From the International Collaboration of Comprehensive Physiologic Assessment Registry (NCT03690713), a total of 330 patients (338 vessels) who had coronary stenosis with FFR ≤ 0.80 but CFR > 2.0 were selected for the current analysis. Patient-level clinical outcome was assessed by major adverse cardiac events (MACE) at 5 years, a composite of all-cause death, target-vessel myocardial infarction (MI), or target-vessel revascularization. Among the study population, 231 patients (233 vessels) underwent PCI and 99 patients (105 vessels) were deferred. During 5 years of follow-up, cumulative incidence of MACE was 13.0% (31 patients) without significant difference between PCI and deferred groups (12.7% vs. 14.0%, adjusted HR 1.301, 95% CI 0.611–2.769, P = 0.495). Multiple sensitivity analyses by propensity score matching and inverse probability weighting also showed no significant difference in patient-level MACE and vessel-specific MI or revascularization. In this hypothesis-generating study, there was no significant difference in clinical outcomes between PCI and deferred groups among patients with intermediate stenosis with FFR ≤ 0.80 but CFR > 2.0. Further study is needed to confirm this finding.Clinical Trial Registration: International Collaboration of Comprehensive Physiologic Assessment Registry (NCT03690713; registration date: 10/01/2018).

scholarly journals IN VIVO, IN VITRO AND IN SILICO COMPARISON OF TWO DEVICES TO MEASURE FRACTIONAL FLOW RESERVE

2018 ◽  
Vol 71 (11) ◽  
pp. A1082
Author(s):  
Stephane Carlier ◽  
Julien Saussez ◽  
Alessandro Scalia ◽  
Kamil Chodzynski ◽  
Shunji Nishio ◽  
...  
Keyword(s):  
Fractional Flow Reserve ◽  
In Silico ◽  
Fractional Flow ◽  
Flow Reserve

scholarly journals The Reasons Why Fractional Flow Reserve and Instance Wave-Free Ratio are Similar Using Wave Separation Analysis

2020 ◽  
Author(s):  
Soohong Min ◽  
Gwansuk Kang ◽  
Dong-Guk Paeng ◽  
Joon Hyouk Choi
Keyword(s):  
Fractional Flow Reserve ◽  
Circulation System ◽  
Fractional Flow ◽  
Wave Separation ◽  
Flow Reserve ◽  
Stenosis Severity ◽  
The Relationship ◽  
Wedge Pressure

Abstract Background and Objectives: Fractional flow reserve(FFR) and instantaneous wave-free ratio(iFR) are the two most commonly used coronary indices of physiological stenosis severity based on pressure. To minimize the effect of wedge pressure (Pwedge), FFR is measured during hyperemia conditions, and iFR is calculated as the ratio of distal and aortic pressures (Pd/Pa) in the wave-free period. The goal of this study was to predict Pwedge using the backward wave (Pback) through wave separation analysis(WSA) and to reflect the effect of Pwedge on FFR and iFR to identify the relationship between the two indices.Methods: An in vitro circulation system was constructed to calculate Pwedge. The measurements were performed in cases with stenosis percentages of 48, 71, and 88% and with hydrostatic pressures of 10 and 30 mmHg. Then, the correlation between Pback by WSA and Pwedge was calculated. In vivo coronary flow and pressure were simultaneously measured for 11 vessels in all patients. The FFR and iFR values were reconstructed as the ratios of forward wave at distal and proximal sites during hyperemia and at rest, respectively.Results: Based on the in vitro results , the correlation between Pback and Pwedge was high(r=0.990, p<0.0001). In vivo results showed high correlations between FFR and reconstructed FFR(r=0.992, p<0.001) and between iFR and reconstructed iFR(r=0.930, p<0.001).Conclusions: Reconstructed FFR and iFR were in good agreement with conventional FFR and iFR. FFR and iFR can be expressed as the variation of trans-stenotic forward pressure, indicating that the two values are inferred from the same formula under different conditions.

scholarly journals Discordance Between Fractional Flow Reserve and Coronary Flow Reserve

2017 ◽  
Vol 10 (10) ◽  
pp. 999-1007 ◽  
Author(s):  
Sung Gyun Ahn ◽  
Jon Suh ◽  
Olivia Y. Hung ◽  
Hee Su Lee ◽  
Yasir H. Bouchi ◽  
...  
Keyword(s):  
Coronary Flow Reserve ◽  
Fractional Flow Reserve ◽  
Coronary Flow ◽  
Fractional Flow ◽  
Flow Reserve

Abstract 14743: Usefulness of Estimated Coronary Flow Velocity Using Quantitative Flow Ratio for Intermediate Coronary Stenosis

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Eiji Ichimoto ◽  
Nao Konagai ◽  
Sawako Horie ◽  
Atsushi Hasegawa ◽  
Hirofumi Miyahara ◽  
...  
Keyword(s):  
Flow Velocity ◽  
Coronary Stenosis ◽  
Coronary Flow ◽  
Flow Ratio ◽  
Operating Characteristics ◽  
Fractional Flow ◽  
Coronary Flow Velocity ◽  
Flow Reserve ◽  
Quantitative Flow Ratio ◽  
Quantitative Flow

Introduction: Quantitative flow ratio (QFR) is a diagnostic modality for functional assessment for intermediate coronary stenosis without the use of pressure wire. QFR is calculated from 3-dimensional quantitative CAG (3D-QCA) using an advanced algorithm that enables fast computation of the pressure drop caused by coronary stenosis. Hypothesis: We assessed the usefulness of QFR and the association with an estimated coronary flow velocity (eCFV) for intermediate coronary stenosis. Methods: A total of 100 lesions in 80 consecutive patients were assessed Fractional Flow Reserve (FFR) for intermediate coronary stenosis between January 2011 and April 2019. Of these, 97 lesions in 77 patients who underwent QFR were included in this study. Patients were classified into two groups (FFR ≤ 0.80 or FFR > 0.80). QFR and eCFV using contrast were measured by Thrombolysis in Myocardial Infarction (TIMI) frame counts. Results: There was no significant differences in target vessels (p = 0.90) and diffuse lesions (p = 0.06) between the two groups (FFR ≤ 0.80 or FFR > 0.80). Mean FFR and QFR values were 0.78 ± 0.12 and 0.77 ± 0.11, respectively. QFR had a good correlation with FFR values (r = 0.86, p < 0.0001). The diagnostic accuracy, sensitivity, and specificity on QFR ≤ 0.80 were 91.8%, 92.7% and 90.5%, respectively. The eCFV of FFR ≤ 0.80 was greater than that of FFR > 0.80 (0.19 ± 0.08 m/s vs. 0.14 ± 0.06 m/s, p<0.001). Figure showed that the eCFV correlated with FFR values (r = -0.29, p < 0.01). Moreover, the eCFV had a high area under the curve (AUC = 0.71, p < 0.01) on Receiver operating characteristics curve (ROC) analysis with FFR ≤ 0.80. Conclusions: QFR was useful for the assessment of functional stenosis severity. As eCFV was faster, FFR was lower for intermediate coronary stenosis. The eCFV had a good correlation with FFR and may become one of the evaluations for ischemia.

Optimal Dosage and Method of Administration of Adenosine for Measuring the Coronary Flow Reserve and the Fractional Flow Reserve in Koreans

2006 ◽  
Vol 36 (4) ◽  
pp. 300 ◽  
Author(s):  
Jung Won Suh ◽  
Bon Kwon Koo ◽  
Sang Ho Jo ◽  
Hyun Jae Kang ◽  
Young Seok Cho ◽  
...  
Keyword(s):  
Coronary Flow Reserve ◽  
Fractional Flow Reserve ◽  
Coronary Flow ◽  
Optimal Dosage ◽  
Fractional Flow ◽  
Flow Reserve
Sign in / Sign up

Export Citation Format

Share Document