OBJECTIVES This study compared the performance of the quantitative flow ratio (QFR) with single-photon emission computed tomography (SPECT) and positron emission tomography (PET) myocardial... Show moreOBJECTIVES This study compared the performance of the quantitative flow ratio (QFR) with single-photon emission computed tomography (SPECT) and positron emission tomography (PET) myocardial perfusion imaging (MPI) for the diagnosis of fractional flow reserve (FFR)-defined coronary artery disease (CAD).BACKGROUND QFR estimates FFR solely based on cine contrast images acquired during invasive coronary angiography (ICA). Head-to-head studies comparing QFR with noninvasive MPI are lacking.METHODS A total of 208 (624 vessels) patients underwent technetium -99m tetrofosmin SPECT and [15O]H2O PET imaging before ICA in conjunction with FFR measurements. ICA was obtained without using a dedicated QFR acquisition protocol, and QFR computation was attempted in all vessels interrogated by FFR (552 vessels).RESULTS QFR computation succeeded in 286 (52%) vessels. QFR correlated well with invasive FFR overall (R = 0.79; p < 0.001) and in the subset of vessels with an intermediate (30% to 90%) diameter stenosis (R = 0.76; p < 0.001). Overall, per-vessel analysis demonstrated QFR to exhibit a superior sensitivity (70%) in comparison with SPECT (29%; p < 0.001), whereas it was similar to PET (75%; p = 1.000). Specificity of QFR (93%) was higher than PET (79%; p < 0.001) and not different from SPECT (96%; p = 1.000). As such, the accuracy of QFR (88%) was superior to both SPECT (82%; p = 0.010) and PET (78%; p = 0.004). Lastly, the area under the receiver operating characteristics curve of QFR, in the overall sample (0.94) and among vessels with an intermediate lesion (0.90) was higher than SPECT (0.63 and 0.61; p < 0.001 for both) and PET (0.82; p < 0.001 and 0.77; p = 0.002), respectively.CONCLUSIONS In this head-to-head comparative study, QFR exhibited a higher diagnostic value for detecting FFRdefined significant CAD compared with perfusion imaging by SPECT or PET. (J Am Coll Cardiol Img 2020;13:1976-85) (c) 2020 by the American College of Cardiology Foundation. Show less
Rabbat, M.; Leipsic, J.; Bax, J.; Kauh, B.; Verma, R.; Doukas, D.; ... ; Lopez, J. 2020
Objectives: In the United States, the real-world feasibility and outcome of using fractional flow reserve from coronary computed tomography angiography (FFRCT) is unknown. We sought to determine... Show moreObjectives: In the United States, the real-world feasibility and outcome of using fractional flow reserve from coronary computed tomography angiography (FFRCT) is unknown. We sought to determine whether a strategy that combined coronary computed tomography angiography (CTA) and FFRCT could safely reduce the need for invasive coronary angiography (ICA), as compared to coronary CTA alone. Methods: The study included 387 consecutive patients with suspected CAD referred for coronary CTA with selective FFRCT and 44 control patients who underwent CTA alone. Lesions with 30-90% diameter stenoses were considered of indeterminate hemodynamic significance and underwent FFRCT. Nadir FFRCT <= 0.80 was positive. The rate of patients having ICA, revascularization and major adverse cardiac events were recorded. Results: Using coronary CTA and selective FFRCT, 121 patients (32%) had at least one vessel with >= 50% diameter stenosis; 67/121 (55%) patients had at least one vessel with FFRCT <= 0.80; 55/121 (45%) underwent ICA; and 34 were revascularized. The proportion of ICA patients undergoing revascularization was 62% (34 of 55). The number of patients with vessels with 30-50% diameter of stenosis was 90 (23%); 28/90 (31%) patients had at least one vessel with FFRCT <= 0.80; 8/90 (9%) underwent ICA; and five were revascularized. In our institutional practice, compared to coronary CTA alone, coronary CTA with selective FFRCT reduced the rates of ICA (45% vs. 80%) for those with obstructive CAD. Using coronary CTA with selective FFRCT, no major adverse cardiac events occurred over a mean follow-up of 440 days. Conclusion: FFRCT safely deferred ICA in patients with CAD of indeterminate hemodynamic significance. A high proportion of those who underwent ICA were revascularized. Show less
OBJECTIVES The 1-year data from the international ADVANCE (Assessing Diagnostic Value of Non-invasive FFRCT in Coronary Care) Registry of patients undergoing coronary computed tomography... Show moreOBJECTIVES The 1-year data from the international ADVANCE (Assessing Diagnostic Value of Non-invasive FFRCT in Coronary Care) Registry of patients undergoing coronary computed tomography angiography (CTA) was used to evaluate the relationship of fractional flow reserve derived from coronary CTA (FFRCT) with downstream care and clinical outcomes.BACKGROUND Guidelines for management of chest pain using noninvasive imaging pathways are based on short- to intermediate-term outcomes.METHODS Patients (N = 5,083) evaluated for clinically suspected coronary artery disease and in whom atherosclerosis was identified by coronary CTA were prospectively enrolled at 38 international sites from July 15, 2015, to October 20, 2017. Demographics, symptom status, coronary CTA and FFRCT findings and resultant site-based treatment plans, and clinical outcomes through 1 year were recorded and adjudicated by a blinded core laboratory. Major adverse cardiac events (MACE), death, myocardial infarction (MI), and acute coronary syndrome leading to urgent revascularization were captured.RESULTS At 1 year, 449 patients did not have follow-up data. Revascularization occurred in 1,208 (38.40%) patients with an FFRCT <= 0.80 and in 89 (5.60%) with an FFRCT >0.80 (relative risk [RR]: 6.87; 95% confidence interval [CI]: 5.59 to 8.45; p < 0.001). MACE occurred in 55 patients, 43 events occurred in patients with an FFRCT <= 0.80 and 12 occurred in those with an FFRCT >0.80 (RR: 1.81; 95% CI: 0.96 to 3.43; p = 0.06). Time to first event (all-cause death or MI) occurred in 38 (1.20%) patients with an FFRCT <= 0.80 compared with 10 (0.60%) patients with an FFRCT >0.80 (RR: 1.92; 95% CI: 0.96 to 3.85; p = 0.06). Time to first event (cardiovascular death or MI) occurred cardiovascular death or MI occurred more in patients with an FFRCT <= 0.80 compared with patients with an FFRCT >0.80 (25 [0.80%] vs. 3 [0.20%]; RR: 4.22; 95% CI: 1.28 to 13.95; p = 0.01).CONCLUSIONS The 1-year outcomes from the ADVANCE FFRCT Registry show low rates of events in all patients, with less revascularization and a trend toward lower MACE and significantly lower cardiovascular death or MI in patients with a negative FFRCT compared with patients with abnormal FFRCT values. (Assessing Diagnostic Value of Non-invasive FFRCT in Coronary Wave [ADVANCE]; NCT02499679) (C) 2020 The Authors. Published by Elsevier on behalf of the American College of Cardiology Foundation. Show less
OBJECTIVE. Correcting the perfusion in areas distal to coronary stenosis (risk) according to that of normal (remote) areas defines the relative myocardial perfusion index, which is similar to the... Show moreOBJECTIVE. Correcting the perfusion in areas distal to coronary stenosis (risk) according to that of normal (remote) areas defines the relative myocardial perfusion index, which is similar to the fractional flow reserve (FFR) concept. The aim of this study was to assess the value of relative myocardial perfusion by MRI in predicting lesion-specific inducible ischemia as defined by FFR.MATERIALS AND METHODS. Forty-six patients (33 men and 13 women; mean [+/- SD] age, 61 +/- 9 years) who underwent adenosine perfusion MRI and FFR measurement distal to 49 coronary artery stenoses during coronary angiography were retrospectively evaluated. Subendocardial time-enhancement maximal upslopes, normalized by the respective left ventricle cavity upslopes, were obtained in risk and remote subendocardium during adenosine and rest MRI perfusion and were correlated to the FFR values.RESULTS. The mean FFR value was 0.84 +/- 0.09 (range, 0.60-0.98) and was less than or equal to 0.80 in 31% of stenoses (n = 15). The relative subendocardial perfusion index (risk-to-remote upslopes) during hyperemia showed better correlations with the FFR value (r = 0.59) than the uncorrected risk perfusion parameters (i.e., both the upslope during hyperemia and the perfusion reserve index [stress-to-rest upslopes]; r = 0.27 and 0.29, respectively). A cutoff value of 0.84 of the relative subendocardial perfusion index had an ROC AUC of 0.88 to predict stenosis at an FFR of less than or equal to 0.80.CONCLUSION. Using adenosine perfusion MRI, the relative myocardial perfusion index enabled the best prediction of FFR-defined lesion-specific myocardial ischemia. This index could be used to noninvasively determine the need for revascularization of known coronary stenoses. Show less
