448 Comparison of quantitative flow ratio, Pd/Pa, and diastolic hyperaemia-free ratio vs. fractional flow reserve in non-culprit lesion of patients with non-ST-segment elevation myocardial infarction

Abstract

Aims To investigate the correlation between quantitative flow ratio (QFR), Pd/Pa, diastolic hyperaemia-free ratio (DFR), and fractional flow reserve (FFR, gold standard) in non-culprit lesion (NCL) of patients with non ST-segment elevation myocardial infarction (NSTEMI). The non-hyperemic pressure ratio (NHPR) and the angiography-based indexes have been developed to overcome the limitation of the use of the FFR. Methods and results Between January and December 2019, 184 NCL from 116 NSTEMI patients underwent physiologic assessment and were included in the study. NCLs were investigated with QFR, Pd/Pa, DFR, and FFR. Mean values of QFR, Pd/Pa, DFR, and FFR were 0.85 ± 0.10, 0.92 ± 0.07, 0.93 ± 0.05, and 0.84 ± 0.07, respectively. DFR and FFR showed a good correlation (r = 0.76). Bland and Altman plot showed a mean difference of 0.080. DFR diagnostic accuracy was 88%. The area under the ROC curve (AUC) for DFR was 0.946 (95% CI: 0.90–0.97, P = 0.0001). Similar findings were reported for Pd/Pa [r = 0.73; mean difference 0.095, diagnostic accuracy 84%, AUC 0.909 (95% CI: 0.85–0.94, P = 0.0001)] and QFR [r = 0.68; mean difference: 0.01; diagnostic accuracy: 88%, AUC: 0.964 (95% CI: 0.91–0.98, P = 0.0001)]. FFR, QFR, Pd/Pa, and DFR identified 31%, 32%, 30%, and 32% potentially flow-limiting lesions, respectively. Conclusions In NSTEMI patients, QFR, Pd/Pa, and DFR showed equivalence as compared to gold standard FFR in the discrimination of non-culprit lesions requiring revascularization.

Quantitative Flow Ratio or Angiography for the Assessment of Non-culprit Lesions in Acute Coronary Syndromes: Protocol of the Randomized Trial QUOMODO

“…Addressing this problem, our study investigates whether QFR guidance provides a better estimate of the severity of non-culprit lesions compared with angiography. Of importance, Tebaldi et al recently reported that QFR, Pd/Pa and DFR are equivalent to the gold standard FFR in the discrimination of non-culprit lesions requiring revascularization in patients with NSTEMI who have received PCI of all culprit lesions ( 18 ). Our study tests the hypothesis that QFR could provide a better stratification of patients/lesions requiring PCI for non-culprit lesions as compared to angiography, leading to more accurate identification of lesions requiring PCI and to reduced angina during follow-up.…”

“…The area under the summary receiver operating characteristic (sROC) curve for QFR was 0.94 ( 13 ). Further, QFR has been validated by several studies in the context of non-culprit lesions of ACS ( 14 – 18 ).…”

Diagnostic performance of quantitative flow ratio, non-hyperaemic pressure indices and fractional flow reserve for the assessment of coronary lesions in severe aortic stenosis

“…Though non-hyperaemic indices are an attractive solution for assessing physiological significance, a less invasive option would be the avoidance of wire-based techniques and QFR has emerged as one potential technology to address this problem. The technology is well-validated in patients without aortic stenosis (20)(21)(22)(23)(24), including in patients with myocardial infarction (24)(25)(26), and growing evidence is building for its validation in aortic stenosis (27,28). With this as a background, the present compared the diagnostic performance of QFR against not only FFR, but also multiple non-hyperaemic indices (iFR, dPR and Pd/Pa) in the setting of severe aortic stenosis.…”

“…QFR demonstrated an excellent discriminatory power to predict functionally significant FFR (AUC =0.92; 95% CI: 0.84 to 1.00; P<0.001) (Figure 3A) with good diagnostic Family history of IHD 9 [26] Previous MI, n (%) 4 [11] Previous CVA or TIA, n (%) 4 [11] Peripheral vascular disease, n (%) 1 [3] Atrial fibrillation, n (%) 4 [11] Chronic kidney disease, n (%) 3 [9] Echocardiographic parameters Diagonal artery 5 [9] Ramus intermedius artery 1 [2] Left circumflex artery 5 [9] Obtuse marginal artery 9 [16] Right coronary artery 3 [5] Posterior descending artery 3 [5] performance [sensitivity, 73%, specificity 91%, positive predictive value (PPV) 84%, negative predictive value (NPV) 84%, accuracy 84%] (Tables 3,4). QFR demonstrated similar diagnostic performance to iFR (difference in AUC =0.04; 95% CI: −0.04 to 0.12; P=0.…”

Angiographic quantitative flow ratio in acute coronary syndrome: beyond a tool to define ischemia-causing stenosis—a literature review

“…Furthermore, QFR, as a research tool, can be computed both offline and online, allowing clinicians to wildly review available angiograms from a functional perspective. With these advantages, accumulating studies have investigated the diagnostic value of QFR for the functional assessment of NCL in ACS (Table 3) (26)(27)(28)(29)(30)(31)(32)(33)(34)(35).…”