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Predictors of fractional flow reserve/instantaneous wave-free ratio discordance: impact of tailored diagnostic cut-offs on clinical outcomes of deferred lesions. De Filippo Ovidio,Gallone Guglielmo,D'Ascenzo Fabrizio,Leone Antonio Maria,Mancone Massimo,Quadri Giorgio,Barbieri Lucia,Bossi Irene,Boccuzzi Giacomo,Montone Rocco Antonio,Burzotta Francesco,Iannaccone Mario,Montefusco Antonio,Carugo Stefano,Castelli Chiara,Oreglia Jacopo,Cerrato Enrico,Peirone Andrea,Zaccardo Giuseppe,Sardella Gennaro,Niccoli Giampaolo,Omedè Pierluigi,Varbella Ferdinando,Rognoni Andrea,Trani Carlo,Conrotto Federico,Escaned Javier,De Ferrari Gaetano Maria Journal of cardiovascular medicine (Hagerstown, Md.) BACKGROUND:Patient-related and lesion-related factors may influence instantaneous wave-free ratio (iFR)/fractional flow reserve (FFR) concordance, potentially affecting the safety of revascularization deferral. METHODS:Consecutive patients with at least an intermediate coronary stenosis evaluated by both iFR and FFR were retrospectively enrolled. The agreement between iFR and FFR at their diagnostic cut-offs (FFR 0.80, iFR 0.89) was assessed. Predictors of discordance were assessed using multivariate analyses. Tailored iFR cut-offs according to predictors of discordance best matching an FFR of 0.80 were identified. The impact of reclassification according to tailored iFR cut-offs on major cardiovascular events (MACE: cardiovascular death, myocardial infarction or target-lesion revascularization) among deferred lesions was investigated. RESULTS:Two hundred and ninety-nine intermediate coronary stenosis [FFR 0.84 (0.78-0.89), iFR 0.91 (0.87-0.95), 202 left main/left anterior descending (LM/LAD) vessels, 67.6%] of 260 patients were studied. Discordance rate was 23.4% (n = 70, 10.7% iFR-negative discordant, 12.7% iFR-positive discordant). Predictors of discordance were LM/LAD disease, multivessel disease, non-ST-elevation myocardial infarction, smoking, reduced eGFR and hypertension. Lesion reclassification with tailored iFR cut-offs based on patient-level predictors carried no prognostic value among deferred lesions. Reclassification according to lesion location, which was entirely driven by LM/LAD lesions (iFR cut-offs: 0.93 for LM/LAD, 0.89 for non-LM/LAD), identified increased MACE among lesions deferred based on a negative FFR, between patients with a positive as compared with a negative iFR (19.4 vs. 6.1%, P = 0.044), whereas the same association was not observed with the conventional 0.89 iFR cut-off (15 vs. 8.6%, P = 0.303). CONCLUSION:Tailored vessel-based iFR cut-offs carry prognostic value among FFR-negative lesions, suggesting that a one-size-fit-all iFR cut-off might be clinically unsatisfactory. 10.2459/JCM.0000000000001264
Clinical Outcomes Data for Instantaneous Wave-Free Ratio-Guided Percutaneous Coronary Intervention. Younus Masood,Seto Arnold H Interventional cardiology clinics Instantaneous wave-free ratio (iFR) is a vasodilator-free index of coronary blood flow used for revascularization decision-making. iFR-based revascularization also had a decreased rate of adverse effects from vasodilators, shorter procedure times, and lower revascularization rates. iFR-pullback predicts post-percutaneous coronary intervention physiologic outcomes in tandem and diffuse coronary lesions. iFR may be particularly useful in patients with potential adenosine resistance, contraindications to adenosine, and multivessel or serial lesions. iFR is a useful tool both with and without fractional-flow reserve for revascularization planning. 10.1016/j.iccl.2018.11.003
Is Now the Time to Debate Traditional Fractional Flow Reserve/Instantaneous Wave-Free Ratio Cut Points? Davies Justin E,Cook Christopher M Circulation. Cardiovascular interventions 10.1161/CIRCINTERVENTIONS.118.007562
Go With the Flow When Instantaneous Wave-Free Ratio-Fractional Flow Reserve Discordance Occurs: Indeed, Beware When Relying on Fractional Flow Reserve Alone. Stegehuis Valérie E,van de Hoef Tim P,Piek Jan J,Claessen Bimmer E JACC. Cardiovascular interventions 10.1016/j.jcin.2018.09.026
Instantaneous Wave-Free Ratio Outcomes and the Epistemology of Ischemia. Seto Arnold H JACC. Cardiovascular interventions 10.1016/j.jcin.2017.08.007
Use of the Instantaneous Wave-free Ratio or Fractional Flow Reserve in PCI. The New England journal of medicine BACKGROUND:Coronary revascularization guided by fractional flow reserve (FFR) is associated with better patient outcomes after the procedure than revascularization guided by angiography alone. It is unknown whether the instantaneous wave-free ratio (iFR), an alternative measure that does not require the administration of adenosine, will offer benefits similar to those of FFR. METHODS:We randomly assigned 2492 patients with coronary artery disease, in a 1:1 ratio, to undergo either iFR-guided or FFR-guided coronary revascularization. The primary end point was the 1-year risk of major adverse cardiac events, which were a composite of death from any cause, nonfatal myocardial infarction, or unplanned revascularization. The trial was designed to show the noninferiority of iFR to FFR, with a margin of 3.4 percentage points for the difference in risk. RESULTS:At 1 year, the primary end point had occurred in 78 of 1148 patients (6.8%) in the iFR group and in 83 of 1182 patients (7.0%) in the FFR group (difference in risk, -0.2 percentage points; 95% confidence interval [CI], -2.3 to 1.8; P<0.001 for noninferiority; hazard ratio, 0.95; 95% CI, 0.68 to 1.33; P=0.78). The risk of each component of the primary end point and of death from cardiovascular or noncardiovascular causes did not differ significantly between the groups. The number of patients who had adverse procedural symptoms and clinical signs was significantly lower in the iFR group than in the FFR group (39 patients [3.1%] vs. 385 patients [30.8%], P<0.001), and the median procedural time was significantly shorter (40.5 minutes vs. 45.0 minutes, P=0.001). CONCLUSIONS:Coronary revascularization guided by iFR was noninferior to revascularization guided by FFR with respect to the risk of major adverse cardiac events at 1 year. The rate of adverse procedural signs and symptoms was lower and the procedural time was shorter with iFR than with FFR. (Funded by Philips Volcano; DEFINE-FLAIR ClinicalTrials.gov number, NCT02053038 .). 10.1056/NEJMoa1700445
Instantaneous Wave-free Ratio versus Fractional Flow Reserve. Montone Rocco A,Minelli Silvia The New England journal of medicine 10.1056/NEJMc1711333
Efficacy and safety of instantaneous wave-free ratio in patients undergoing coronary revascularisation: protocol for a systematic review. Kwong Joey S W,Li Sheyu,Gu Wan-Jie,Chen Hao,Zhang Chao,Zeng Xian-Tao,Yu Cheuk-Man BMJ open INTRODUCTION:Effective selection of coronary lesions for revascularisation is pivotal in the management of symptoms and adverse outcomes in patients with coronary artery disease. Recently, instantaneous 'wave-free' ratio (iFR) has been proposed as a new diagnostic index for assessing the severity of coronary stenoses without the need of pharmacological vasodilation. Evidence of the effectiveness of iFR-guided revascularisation is emerging and a systematic review is warranted. METHODS AND ANALYSIS:This is a protocol for a systematic review of randomised controlled trials and controlled observational studies. Electronic sources including MEDLINE via Ovid, Embase, Cochrane databases and ClinicalTrials.gov will be searched for potentially eligible studies investigating the effects of iFR-guided strategy in patients undergoing coronary revascularisation. Studies will be selected against transparent eligibility criteria and data will be extracted using a prestandardised data collection form by two independent authors. Risk of bias in included studies and overall quality of evidence will be assessed using validated methodological tools. Meta-analysis will be performed using the Review Manager software. Our systematic review will be performed according to the guidance from the Cochrane Handbook for Systematic Reviews of Interventions and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. ETHICS AND DISSEMINATION:Ethics approval is not required. Results of the systematic review will be disseminated as conference proceedings and peer-reviewed journal publication. TRIAL REGISTRATION NUMBER:This protocol is registered in the International Prospective Register of Systematic Reviews (PROSPERO), registration number CRD42017065460. 10.1136/bmjopen-2017-017868
Revascularization and Mortality at 5 Years After Treatment Guided By Instantaneous Wave-Free Ratio and Fractional Flow Reserve: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Journal of the American Heart Association 10.1161/JAHA.123.032015
Instantaneous Wave-free Ratio versus Fractional Flow Reserve to Guide PCI. Götberg Matthias,Christiansen Evald H,Gudmundsdottir Ingibjörg J,Sandhall Lennart,Danielewicz Mikael,Jakobsen Lars,Olsson Sven-Erik,Öhagen Patrik,Olsson Hans,Omerovic Elmir,Calais Fredrik,Lindroos Pontus,Maeng Michael,Tödt Tim,Venetsanos Dimitrios,James Stefan K,Kåregren Amra,Nilsson Margareta,Carlsson Jörg,Hauer Dario,Jensen Jens,Karlsson Ann-Charlotte,Panayi Georgios,Erlinge David,Fröbert Ole, The New England journal of medicine BACKGROUND:The instantaneous wave-free ratio (iFR) is an index used to assess the severity of coronary-artery stenosis. The index has been tested against fractional flow reserve (FFR) in small trials, and the two measures have been found to have similar diagnostic accuracy. However, studies of clinical outcomes associated with the use of iFR are lacking. We aimed to evaluate whether iFR is noninferior to FFR with respect to the rate of subsequent major adverse cardiac events. METHODS:We conducted a multicenter, randomized, controlled, open-label clinical trial using the Swedish Coronary Angiography and Angioplasty Registry for enrollment. A total of 2037 participants with stable angina or an acute coronary syndrome who had an indication for physiologically guided assessment of coronary-artery stenosis were randomly assigned to undergo revascularization guided by either iFR or FFR. The primary end point was the rate of a composite of death from any cause, nonfatal myocardial infarction, or unplanned revascularization within 12 months after the procedure. RESULTS:A primary end-point event occurred in 68 of 1012 patients (6.7%) in the iFR group and in 61 of 1007 (6.1%) in the FFR group (difference in event rates, 0.7 percentage points; 95% confidence interval [CI], -1.5 to 2.8; P=0.007 for noninferiority; hazard ratio, 1.12; 95% CI, 0.79 to 1.58; P=0.53); the upper limit of the 95% confidence interval for the difference in event rates fell within the prespecified noninferiority margin of 3.2 percentage points. The results were similar among major subgroups. The rates of myocardial infarction, target-lesion revascularization, restenosis, and stent thrombosis did not differ significantly between the two groups. A significantly higher proportion of patients in the FFR group than in the iFR group reported chest discomfort during the procedure. CONCLUSIONS:Among patients with stable angina or an acute coronary syndrome, an iFR-guided revascularization strategy was noninferior to an FFR-guided revascularization strategy with respect to the rate of major adverse cardiac events at 12 months. (Funded by Philips Volcano; iFR SWEDEHEART ClinicalTrials.gov number, NCT02166736 .). 10.1056/NEJMoa1616540
Coronary revascularization guided by instantaneous wave-free ratio compared with fractional flow reserve: pooled 5-year mortality in the DEFINE-FLAIR and iFR-SWEDEHEART trials. European heart journal 10.1093/eurheartj/ehad552
Instantaneous wave-free ratio compared with fractional flow reserve: time for rethinking current recommendations. European heart journal 10.1093/eurheartj/ehad574
Impact of instantaneous wave-free ratio on graft failure after coronary artery bypass graft surgery. Wada Teruaki,Shiono Yasutsugu,Kubo Takashi,Honda Kentaro,Takahata Masahiro,Shimamura Kunihiro,Yuzaki Mitsuru,Tanimoto Takashi,Matsuo Yoshiki,Tanaka Atsushi,Hozumi Takeshi,Nishimura Yoshiharu,Akasaka Takashi International journal of cardiology BACKGROUND:We aimed to assess an impact of instantaneous wave-free ratio (iFR) on a graft failure after coronary artery bypass grafting (CABG). METHODS AND RESULTS:A total of 131 coronary arteries from 88 patients who underwent invasive coronary angiography, intracoronary pressure measurements, CABG, and scheduled follow-up coronary computed tomography angiography within one year were investigated. All studied arteries had FFR <0.80. The rate of graft failure was significantly higher in vessels with negative iFR (>0.89) than in those with positive iFR (<0.89) (25.7% vs. 7.3%, p = 0.012). The graft failure rates increased as the preoperative iFR values rose (iFR <0.80, 3.3%; iFR: 0.80-0.84, 5.6%; iFR: 0.85-0.89, 16.0%; iFR: 0.90-0.94, 28.0%; and iFR: 0.95-1.00, 50.0%; p = 0.002). A cut-off value of iFR to predict graft failures was determined as 0.84 by receiver-operating characteristic curve analysis with sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 88%, 62%, 25%, 97%, and 66%, respectively. CONCLUSIONS:The risk of graft failure becomes higher, as the preoperative iFR increases. The graft failure is significantly more frequent when a bypass graft is anastomosed on vessels with negative iFR than those with positive iFR. 10.1016/j.ijcard.2020.09.046
Relationship between instantaneous wave-free ratio and fractional flow reserve in patients receiving hemodialysis. Morioka Yuta,Arashi Hiroyuki,Otsuki Hisao,Yamaguchi Junichi,Hagiwara Nobuhisa Cardiovascular intervention and therapeutics Instantaneous wave-free ratio (iFR) is a vasodilator-free index and is reported to have a good correlation with fractional flow reserve (FFR). Hemodialysis patients exhibit left ventricular hypertrophy, reduced arterial compliance, and impaired microcirculation. Such a coronary flow condition in these patients may influence the relationship between iFR and FFR. This study assessed the impact of hemodialysis on the relationship between iFR and FFR. The study enrolled 196 patients with 265 stenoses who underwent assessment via iFR, FFR assessment, and right heart catheterization. A good correlation between iFR and FFR was observed in hemodialysis patients. iFR in the hemodialysis group was significantly lower than in the non-hemodialysis group (0.81 ± 0.13 vs. 0.86 ± 0.13, p = 0.005), although no significant difference was found in FFR and percentage diameter stenosis. An iFR value of 0.84 was found to be equivalent to an FFR value of 0.8 in hemodialysis patients, which was lower than the standard predictive iFR range for ischemia. Vasodilator-free assessment by iFR could be beneficial in evaluating intermediate coronary stenosis in patients receiving hemodialysis. However, the threshold for iFR abnormality needs adjustment in hemodialysis patients, and larger clinical trials are required to confirm the results in this specific subset. 10.1007/s12928-017-0479-4
Instantaneous wave-free ratio and fractional flow reserve in clinical practice. Pisters R,Ilhan M,Veenstra L F,Gho B C G,Stein M,Hoorntje J C A,Rasoul S Netherlands heart journal : monthly journal of the Netherlands Society of Cardiology and the Netherlands Heart Foundation OBJECTIVES:To compare fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) measurements in an all-comer patient population with moderate coronary artery stenoses. BACKGROUND:Visual assessment of the severity of coronary artery stenoses is often discordant in moderate lesions. FFR allows reliable functional severity assessment in these cases but requires adenosine-induced hyperaemia with associated additional time, costs and side effects. The iFR is a hyperaemia-independent index. METHODS AND RESULTS:Between November 2015 and February 2017, 356 consecutive patients were included in whom 515 coronary stenoses were measured using both iFR and FFR. Mean iFR and FFR were 0.90 ± 0.09 and 0.86 ± 0.08, respectively. iFR correlated well with FFR [r = 0.75; p < 0.001]. Receiver operating characteristic analysis identified an area under the curve of 0.92. An iFR-only strategy with a treatment cut-off ≤0.89 revealed a diagnostic classification agreement with the FFR-only strategy in 420 lesions (82%) with a sensitivity of 87%, a specificity of 80%, a positive predictive value of 56% and a negative predictive value of 96%. CONCLUSIONS:Real-time iFR measurements have good negative predictive value compared to FFR, but moderate diagnostic accuracy (82%). It exposes fewer patients to adenosine, reduces procedure time and costs. Further prospective trials are needed to evaluate specific clinical settings, cut-off values and endpoints. 10.1007/s12471-018-1125-1
Safety of the Deferral of Coronary Revascularization on the Basis of Instantaneous Wave-Free Ratio and Fractional Flow Reserve Measurements in Stable Coronary Artery Disease and Acute Coronary Syndromes. Escaned Javier,Ryan Nicola,Mejía-Rentería Hernán,Cook Christopher M,Dehbi Hakim-Moulay,Alegria-Barrero Eduardo,Alghamdi Ali,Al-Lamee Rasha,Altman John,Ambrosia Alphonse,Baptista Sérgio B,Bertilsson Maria,Bhindi Ravinay,Birgander Mats,Bojara Waldemar,Brugaletta Salvatore,Buller Christopher,Calais Fredrik,Silva Pedro Canas,Carlsson Jörg,Christiansen Evald H,Danielewicz Mikael,Di Mario Carlo,Doh Joon-Hyung,Erglis Andrejs,Erlinge David,Gerber Robert T,Going Olaf,Gudmundsdottir Ingibjörg,Härle Tobias,Hauer Dario,Hellig Farrel,Indolfi Ciro,Jakobsen Lars,Janssens Luc,Jensen Jens,Jeremias Allen,Kåregren Amra,Karlsson Ann-Charlotte,Kharbanda Rajesh K,Khashaba Ahmed,Kikuta Yuetsu,Krackhardt Florian,Koo Bon-Kwon,Koul Sasha,Laine Mika,Lehman Sam J,Lindroos Pontus,Malik Iqbal S,Maeng Michael,Matsuo Hitoshi,Meuwissen Martijn,Nam Chang-Wook,Niccoli Giampaolo,Nijjer Sukhjinder S,Olsson Hans,Olsson Sven-Erik,Omerovic Elmir,Panayi Georgios,Petraco Ricardo,Piek Jan J,Ribichini Flavo,Samady Habib,Samuels Bruce,Sandhall Lennart,Sapontis James,Sen Sayan,Seto Arnold H,Sezer Murat,Sharp Andrew S P,Shin Eun-Seok,Singh Jasvindar,Takashima Hiroaki,Talwar Suneel,Tanaka Nobuhiro,Tang Kare,Van Belle Eric,van Royen Niels,Varenhorst Christoph,Vinhas Hugo,Vrints Christiaan J,Walters Darren,Yokoi Hiroyoshi,Fröbert Ole,Patel Manesh R,Serruys Patrick,Davies Justin E,Götberg Matthias JACC. Cardiovascular interventions OBJECTIVES:The aim of this study was to investigate the clinical outcomes of patients deferred from coronary revascularization on the basis of instantaneous wave-free ratio (iFR) or fractional flow reserve (FFR) measurements in stable angina pectoris (SAP) and acute coronary syndromes (ACS). BACKGROUND:Assessment of coronary stenosis severity with pressure guidewires is recommended to determine the need for myocardial revascularization. METHODS:The safety of deferral of coronary revascularization in the pooled per-protocol population (n = 4,486) of the DEFINE-FLAIR (Functional Lesion Assessment of Intermediate Stenosis to Guide Revascularisation) and iFR-SWEDEHEART (Instantaneous Wave-Free Ratio Versus Fractional Flow Reserve in Patients With Stable Angina Pectoris or Acute Coronary Syndrome) randomized clinical trials was investigated. Patients were stratified according to revascularization decision making on the basis of iFR or FFR and to clinical presentation (SAP or ACS). The primary endpoint was major adverse cardiac events (MACE), defined as the composite of all-cause death, nonfatal myocardial infarction, or unplanned revascularization at 1 year. RESULTS:Coronary revascularization was deferred in 2,130 patients. Deferral was performed in 1,117 patients (50%) in the iFR group and 1,013 patients (45%) in the FFR group (p < 0.01). At 1 year, the MACE rate in the deferred population was similar between the iFR and FFR groups (4.12% vs. 4.05%; fully adjusted hazard ratio: 1.13; 95% confidence interval: 0.72 to 1.79; p = 0.60). A clinical presentation with ACS was associated with a higher MACE rate compared with SAP in deferred patients (5.91% vs. 3.64% in ACS and SAP, respectively; fully adjusted hazard ratio: 0.61 in favor of SAP; 95% confidence interval: 0.38 to 0.99; p = 0.04). CONCLUSIONS:Overall, deferral of revascularization is equally safe with both iFR and FFR, with a low MACE rate of about 4%. Lesions were more frequently deferred when iFR was used to assess physiological significance. In deferred patients presenting with ACS, the event rate was significantly increased compared with SAP at 1 year. 10.1016/j.jcin.2018.05.029
Differences Between Fractional Flow Reserve and Instantaneous Wave-Free Ratio Clarified by Consideration of a Mathematical Model of Diffuse Coronary Stenosis. Yoshikawa Yusuke,Saito Naritatsu JACC. Cardiovascular interventions 10.1016/j.jcin.2018.07.022
Instantaneous wave-free ratio (iFR) to determine hemodynamically significant coronary stenosis: A comprehensive review. World journal of cardiology Coronary angiography is considered to be the gold standard in the morphological evaluation of coronary artery stenosis. The morphological assessment of the severity of a coronary lesion is very subjective. Thus, the invasive fractional flow reserve (FFR) measurement represents the current standard for estimation of the hemodynamic significance of coronary artery stenosis. The FFR-guided revascularization strategy was initially classified as a Class-IA-recommendation in the 2014 European Society of Cardiology/European Association for Cardio-Thoracic Surgery guidelines on myocardial revascularization. Both the Deferral Performance of Percutaneous Coronary Intervention of Functionally Non-Significant Coronary Stenosis and Flow Reserve Angiography for Multivessel Evaluation studies showed no treatment advantage for hemodynamically insignificant stenoses. With the help of FFR (and targeted interventions), clinical results could be improved; however, the use in clinical practice is still limited due to the need of adenosine administration and a significant prolongation of the length of the procedure. Instantaneous wave-free ratio (iFR) is a new innovative approach for the determination of the hemodynamic significance of coronary stenosis, which can be obtained at rest without the use of vasodilators. Regarding the periprocedural complications as well as prognosis, iFR showed non-inferiority to FFR in the SWEDEHEART and DEFINE-FLAIR trials. Furthermore, iFR, enhanced by iFR-pullback, provides the possibility to display the iFR-change over the course of the vessel to create a hemodynamic map. 10.4330/wjc.v10.i12.267