Diagnostic Accuracy of Quantitative Flow Ratio for Assessing Myocardial Ischemia in Prior Myocardial Infarction

Abstract

related coronary arteries. Angiographically severe stenoses in prior-MI-related coronary arteries are not necessary to induce myocardial ischemia because the amount of viable myocardium is reduced. 9-11 Previous studies have demonstrated that FFR can accurately assess the degree of ischemia even in prior-MI-related coronary arteries, 11,12 but QFR may not consider the amount of viable myocardium because this index is estimated from the anatomic information of the epicardial coronary artery. Therefore, we investigated the diagnostic accuracy of QFR in prior-MI-related coronary arteries as compared with FFR. Methods Study PopulationThe present study was a retrospective, single-center study of patients who underwent CAG and FFR. We analyzed a consecutive series of 75 prior-MI-related coronary arteries (examined in 75 patients between July 2012 and December 2016) and a consecutive series of 75 non-prior-MI-related F ractional flow reserve (FFR) is a useful index of the functional significance of a coronary stenosis. 1 It is obtained during routine coronary angiography (CAG) by using a pressure wire. 2 FFR is independent of heart rate, systemic blood pressure and cardiac output and takes into account myocardial territory and viability and collateral perfusion. 2-5 However, FFR has some disadvantages, such as risks of pressure wire injury, side effects of hyperemic agents and additional costs.Quantitative flow ratio (QFR) is a novel approach to assessing the functional severity of a coronary stenosis. It is calculated from 3D quantitative CAG (3D-QCA) using an advanced algorithm that enables fast computation of the pressure drop caused by coronary stenosis.

Diagnostic Performance of QFR for the Evaluation of Intermediate Coronary Artery Stenosis Confirmed by Fractional Flow Reserve

“…Clinical heterogeneity was mostly due to different inclusion criteria. Mejia-Renteria [9] and Emori [13] included patients with myocardial infarction. Emori [13] included two different populations: patients with previous myocardial infarction (MI) and patients without previous MI.…”

“…Mejia-Renteria [9] and Emori [13] included patients with myocardial infarction. Emori [13] included two different populations: patients with previous myocardial infarction (MI) and patients without previous MI. Spitaleri [12] included patients with ST- elevation myocardial infarction (STEMI) and multivessel disease.…”

Meta-Analysis of Diagnostic Performance of Contrast-Fractional Flow Reserve versus Quantitative Flow Ratio for Functional Assessment of Coronary Stenoses

“…Mejia-Renteria et al [26] FAVOR II CHINA [10] Emori et al [24] FAVOR II Europe-Japan [28] Hwang et al [29] Koltowski et al [27] Tie et al [23] Spitaleri et al [21] Yazaki et al [20] Emori et al [22] FAVOR Pilot [9] Stahli et al [30] WIFI II et al [21][25]…”

“…Mejia-Renteria et al [26] FAVOR II CHINA [10] Emori et al [24] FAVOR II Europe-Japan [28] Hwang et al [29] Koltowski et al [27] Tie et al [23] Spitaleri et al [21] 0.4 of sensitivity and specificity for QFR studies were still significant. In metaregression, we identified some factors influencing heterogeneity, but the limited number of studies made it unreliable to undertake subgroup analysis.…”

How Do We Improve the Utility of Fractional Flow Reserve? ― For Precise Diagnosis of Myocardial Ischemia ―

“…14 Fourth, increased microvascular resistance, which is seen in old myocardial infarction, may increase FFR because of impairment of hyperemic coronary flow, which limits maximal and constant vasodilation. 15 In such cases, significant ischemia may be underestimated. Therefore, we should take these factors into consideration to avoid "white noise".…”