OBJECTIVES The aim of this study was to investigate the impact of post-percutaneous coronary intervention (PCI) quantitative flow ratio (QFR) on clinical outcomes in patients with de novo 3-vessel... Show moreOBJECTIVES The aim of this study was to investigate the impact of post-percutaneous coronary intervention (PCI) quantitative flow ratio (QFR) on clinical outcomes in patients with de novo 3-vessel disease (3VD) treated with contemporary PCI.BACKGROUND The clinical impact of post-PCI QFR in patients treated with state-of-the-art PCI for de novo 3VD is undetermined.METHODS All vessels treated in the SYNTAX (SYNergy between percutaneous coronary intervention with TAXus and cardiac surgery) II trial were retrospectively screened and analyzed for post-PCI QFR. The primary endpoint of this substudy was vessel-oriented composite endpoint (VOCE) at 2 years, defined as the composite of vessel-related cardiac death, vessel-related myocardial infarction, and target vessel revascularization. The receiver-operating characteristic curve was used to calculate the optimal cutoff value of post-PCI QFR for predicting 2-year VOCE. All the analyzable vessels were stratified on the basis of the optimal cutoff value.RESULTS A total of 968 vessels treated with PCI were screened. Post-PCIQFR was analyzable in 771 (79.6%) vessels. A total of 52 (6.7%) VOCEs occurredat 2 years. The mean value of post-PCIQFR was 0.91 +/- 0.07. The diagnostic performance of post-PCI QFR to predict 2-year VOCE was moderate (area under the curve: 0.702; 95% confidence interval: 0.633 to 0.772), with the optimal cutoff value of post-PCI QFR for predicting 2-year VOCE 0.91 (sensitivity 0.652, specificity 0.635). The incidence of 2-year VOCE in the vessels with post-PCIQFR<0.91 (n = 284) was significantly higher compared with vessels with post-PCI QFR >= 0.91 (n = 487) (12.0% vs. 3.7%; hazard ratio: 3.37; 95% confidence interval: 1.91 to 5.97; p < 0.001).CONCLUSIONS A higher post-PCI QFR value is associated with improved vessel-related clinical outcomes in state-of the art PCI practice for de novo 3VD. Achieving a post-PCI QFR value >= 0.91 in all treated vessels should be a target when treating de novo 3VD. These findings require confirmation in future prospective trials. (C) 2019 by the American College of Cardiology Foundation. Show less
OBJECTIVES The aims of the present study were to investigate the applicability of quantitative flow ratio (QFR) in patients with 3-vessel disease and to demonstrate the impact of functional SYNTAX ... Show moreOBJECTIVES The aims of the present study were to investigate the applicability of quantitative flow ratio (QFR) in patients with 3-vessel disease and to demonstrate the impact of functional SYNTAX (Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery) score derived from QFR (fSS(QFR)) on clinical outcomes.BACKGROUND The applicability of QFR in patients with 3-vessel disease and the feasibility of fSS(QFR) have not yet been investigated.METHODS All lesions interrogated using instantaneous wave-free ratio and/or fractional flow reserve in the SYNTAX II trial were retrospectively screened and analyzed for QFR. The diagnostic performance of QFR was investigated using hybrid wire-derived pressure assessment (instantaneous wave-free ratio and fractional flow reserve), used in the trial as a reference. Patients with analyzable QFR in 3 vessels were stratified according to fSS(QFR) to evaluate its clinical prognostic value on the basis of 2-year patient-oriented composite endpoint.RESULTS QFRs were analyzable in 71.0% of lesions (836 lesions). The diagnostic performance of QFR to predict binary wire-based ischemia was substantial (area under the curve 0.81, accuracy 73.8%), with a positive predictive value of 85.9%. Independent predictors of diagnostic discordance were lesions in side branches, involvement of bifurcation or trifurcation, and small vessel. According to the 2-year patient-oriented composite endpoint, fSS(QFR) reclassified 26.1% of the patients (36 of 138) in the high-to intermediate-risk group into the low-risk group appropriately (net reclassification improvement 0.32; p < 0.001). The area under the curve for fSS(QFR) to predict the 2-year patient-oriented composite endpoint was higher than that of the classic anatomic SYNTAX score (0.68 vs. 0.56; p = 0.002).CONCLUSIONS QFR demonstrated substantial applicability in patients with 3-vessel disease. The fSS(QFR) has the potential to further refine prognostic risk estimation compared with the classic anatomic SYNTAX score. (c) 2019 by the American College of Cardiology Foundation. Show less