BACKGROUND: The FAVOR (Comparison of Quantitative Flow Ratio Guided and Angiography Guided Percutaneous Intervention in Patients with Coronary Artery Disease) III China trial demonstrated that percutaneous coronary intervention (PCI) lesion selection using quantitative flow ratio (QFR) measurement, a novel angiography-based approach for estimating fractional flow reserve, improved two-year clinical outcomes compared with standard angiography guidance. This study aimed to assess the cost-effectiveness of QFR-guided PCI from the perspective of the current Chinese healthcare system. METHODS: This study is a pre-specified analysis of the FAVOR III China trial, which included 3825 patients randomized between December 25, 2018, and January 19, 2020, from 26 centers in China. Patients with stable or unstable angina pectoris or those ≥72 hours post-myocardial infarction who had at least one lesion with a diameter stenosis between 50% and 90% in a coronary artery with a ≥2.5 mm reference vessel diameter by visual assessment were randomized to a QFR-guided strategy or an angiography-guided strategy with 1:1 ratio. During the two-year follow-up, data were collected on clinical outcomes, quality-adjusted life-years (QALYs), estimated costs of index procedure hospitalization, outpatient cardiovascular medication use, and rehospitalization due to major adverse cardiac and cerebrovascular events (MACCE). The primary analysis calculated the incremental cost-effectiveness ratio (ICER) as the cost per MACCE avoided. An ICER of ¥10,000/MACCE event avoided was considered economically attractive in China. RESULTS: At two years, the QFR-guided group demonstrated a reduced rate of MACCE compared to the angiography-guided group (10.8% vs . 14.7%, P <0.01). Total two-year costs were similar between the groups (¥50,803 ± 21,121 vs . ¥50,685 ± 23,495, P = 0.87). The ICER for the QFR-guided strategy was ¥3055 per MACCE avoided, and the probability of QFR being economically attractive was 64% at a willingness-to-pay threshold of ¥10,000/MACCE avoided. Sensitivity analysis showed that QFR-guided PCI would become cost-saving if the cost of QFR were below ¥3682 (current cost: ¥3800). Cost-utility analysis yielded an ICER of ¥56,163 per QALY gained, with a 53% probability of being cost-effective at a willingness-to-pay threshold of ¥85,000 per QALY gained. CONCLUSION: In patients undergoing PCI, a QFR-guided strategy appears economically attractive compared to angiographic guidance from the perspective of the Chinese healthcare system. TRIAL REGISTRATION ClinicalTrials.gov , NCT03656848.
Humans ; Cost-Benefit Analysis ; Percutaneous Coronary Intervention/methods* ; Male ; Female ; Coronary Angiography/methods* ; Middle Aged ; Aged ; Coronary Artery Disease/surgery* ; Quality-Adjusted Life Years ; Fractional Flow Reserve, Myocardial/physiology*

Fractional flow reserve (FFR), an established modality for functionally assessing coronary artery disease, is increasingly applied to diagnose and manage lower extremity arterial disease. By incorporating functional parameters, FFR enhances revascularization precision by quantifying the hemodynamic impact of stenotic lesions, thereby overcoming limitations of conventional imaging. Key clinical applications in lower extremity disease include functional assessment in moderate intermittent claudication, post-vascular preparation strategy optimization, and predicting revascularization outcomes and complications. Advances in pressure wire and microcatheter systems, alongside non-invasive imaging-derived FFR techniques, are improving its feasibility and applicability. However, widespread adoption is challenged by the complex anatomy of the lower extremity arterial system, frequent severe calcification and diffuse disease, and a current lack of standardized FFR cutoff values. Promoting the standardized use of FFR is crucial for shifting the clinical management paradigm from anatomy-based repair toward functional reconstruction.
Humans ; Lower Extremity/blood supply* ; Peripheral Arterial Disease/diagnosis* ; Fractional Flow Reserve, Myocardial ; Endovascular Procedures/methods* ; Intermittent Claudication/physiopathology*

Coronary artery fractional flow reserve (FFR) is a critical physiological indicator for assessment of impaired blood flow caused by coronary artery stenosis. The wire-based invasive measurement of blood flow pressure gradient across stenosis is the gold standard for clinical measurement of FFR. However, it has the risk of vascular injury and requires the use of vasodilators, increasing the time and overall cost of interventional examination. Coronary imaging is playing an important role in clinical diagnosis of stenotic lesions, evaluation of severity of lesions, and planning of therapies. In recent years, the computation of FFR based on the physiological information of blood flow obtained from routinely collected coronary image data has become a research focus in this field. This technique reduces the cost of physiological assessment of coronary lesions and the use of pressure wires. It is beneficial to strengthen the physiological guidance in interventional therapy. In order to better understand this emerging technique, this paper highlights its implementation principle and diagnostic performance, analyzes practical problems and current challenges in clinical applications, and discusses possible future development.
Humans ; Coronary Vessels/diagnostic imaging* ; Fractional Flow Reserve, Myocardial ; Heart ; Constriction, Pathologic ; Coronary Stenosis/diagnostic imaging*

OBJECTIVE: To investigate the value of coronary computed tomographic angiography (CCTA)-based fractional flow reserve (CT-FFR) and plaque quantitative analysis in predicting adverse outcomes in patients with non-obstructive coronary heart disease (CAD). METHODS: Clinical data of patients with non-obstructive CAD who underwent CCTA at the Affiliated Hospital of Jiangnan University from March 2014 to March 2018 were retrospectively analyzed and followed up, and the occurrence of major adverse cardiovascular event (MACE) was recorded. The patients were divided into MACE and non-MACE groups according to the occurrence of MACE. The clinical data, CCTA plaque characteristics including plaque length, stenosis degree, minimum lumen area, total plaque volume, non-calcified plaque volume, calcified plaque volume, plaque burden (PB) and remodelling index (RI), and CT-FFR were compared between the two groups. Multivaritate Cox proportional risk model was used to evaluate the relationship between clinical factors, CCTA parameters and MACE. The receiver operator characteristic curve (ROC curve) was used to assess the predictive power of outcome prediction model based on different CCTA parameters. RESULTS: Finally 217 patients were included, of which 43 (19.8%) had MACE and 174 (80.2%) did not. The median follow-up interval was 24 (16, 30) months. The CCTA showed that patients in the MACE group had more severe stenosis than that in the non-MACE group [(44.3±3.8)% vs. (39.5±2.5)%], larger total plaque volume and non-calcified plaque volume [total plaque volume (mm³): 275.1 (197.1, 376.9), non-calcified plaque volume (mm³): 161.5 (114.5, 307.8) vs. 117.9 (77.7, 185.5)], PB and RI were larger [PB: 50.2% (42.1%, 54.8%) vs. 45.1% (38.2%, 51.7%), RI: 1.19 (0.93, 1.29) vs. 1.03 (0.90, 1.22)], CT-FFR value was lower [0.85 (0.80, 0.88) vs. 0.92 (0.87, 0.97)], and the differences were statistically significant (all P < 0.05). Cox regression analysis showed that non-calcified plaques volume [hazard ratio (HR) = 1.005. 95% confidence interval (95%CI) was 1.025-4.866], PB ≥ 50% (HR = 3.146, 95%CI was 1.443-6.906), RI ≥ 1.10 (HR = 2.223, 95%CI was 1.002-1.009) and CT-FFR ≤ 0.87 (HR = 2.615, 95%CI was 1.016-6.732) were independent predictors of MACE (all P < 0.05). The model based on CCTA stenosis degree+CT-FFR+quantitative plaque characteristics (including non-calcified plaque volume, RI, PB) [area under the ROC curve (AUC) = 0.91, 95%CI was 0.87-0.95] had significantly better predictive efficacy for adverse outcomes than the model based on CCTA stenosis degree (AUC = 0.63, 95%CI was 0.54-0.71) and the model based on CCTA stenosis degree+CT-FFR (AUC = 0.71, 95%CI was 0.63-0.79; both P < 0.01). CONCLUSIONS CT-FFR and plaque quantitative analysis based on CCTA are helpful in predicting adverse outcomes in patients with non-obstructive CAD. Non-calcified plaque volume, RI, PB and CT-FFR are important predictors of MACE. Compared with the prediction model based on stenosis degree and CT-FFR, the combined plaque quantitative index can significantly improve the prediction efficiency of adverse outcomes in patients with non-obstructive CAD.
Humans ; Fractional Flow Reserve, Myocardial ; Coronary Angiography/methods* ; Constriction, Pathologic ; Retrospective Studies ; ROC Curve ; Predictive Value of Tests ; Plaque, Atherosclerotic/diagnostic imaging* ; Coronary Stenosis/diagnostic imaging* ; Tomography, X-Ray Computed ; Coronary Artery Disease/diagnostic imaging*

Humans ; Coronary Angiography ; Microcirculation ; Coronary Artery Disease/drug therapy* ; Treatment Outcome ; Vascular Resistance ; Coronary Vessels ; Coronary Circulation ; Predictive Value of Tests ; Fractional Flow Reserve, Myocardial

Humans ; Computed Tomography Angiography ; Deep Learning ; Coronary Angiography ; Coronary Artery Disease ; Tomography, X-Ray Computed ; Coronary Stenosis/diagnosis* ; Retrospective Studies ; Fractional Flow Reserve, Myocardial ; Predictive Value of Tests

BACKGROUND: Drug-coated balloons (DCBs) have emerged as potential alternatives to drug-eluting stents in specific lesion subsets for de novo coronary lesions. Quantitative flow ratio (QFR) is a method based on the three-dimensional quantitative coronary angiography and contrast flow velocity during coronary angiography (CAG), obviating the need for an invasive fractional flow reserve procedural. This study aimed to assess the serial angiographic changes of de novo lesions post-DCB therapy and further explore the cut-off values of lesion and vessel QFR, which predict vessel restenosis (diameter stenosis [DS] ≥50%) at mid-term follow-up. METHODS: The data of patients who underwent DCB therapy between January 2014 and December 2019 from the multicenter hospital were retrospectively collected for QFR analysis. From their QFR performances, which were analyzed by CAG images at follow-up, we divided them into two groups: group A, showing target vessel DS ≥50%, and group B, showing target vessel DS <50%. The median follow-up time was 287 days in group A and 227 days in group B. We compared the clinical characteristics, parameters during DCB therapy, and QFR performances, which were analyzed by CAG images between the two groups, in need to explore the cut-off value of lesion/vessel QFR which can predict vessel restenosis. Student's t test was used for the comparison of normally distributed continuous data, Mann-Whitney U test for the comparison of non-normally distributed continuous data, and receiver operating characteristic (ROC) curves for the evaluation of QFR performance which can predict vessel restenosis (DS ≥50%) at mid-term follow-up using the area under the curve (AUC). RESULTS: A total of 112 patients with 112 target vessels were enrolled in this study. Group A had 41 patients, while group B had 71. Vessel QFR and lesion QFR were lower in group A than in group B post-DCB therapy, and the cut-off values of lesion QFR and vessel QFR in the ROC analysis to predict target vessel DS ≥50% post-DCB therapy were 0.905 (AUC, 0.741 [95% confidence interval, CI: 0.645, 0.837]; sensitivity, 0.817; specificity, 0.561; P < 0.001) and 0.890 (AUC, 0.796 [95% CI: 0.709, 0.882]; sensitivity, 0.746; specificity, 0.780; P < 0.001). CONCLUSIONS The cut-off values of lesion QFR and vessel QFR can assist in predicting the angiographic changes post-DCB therapy. When lesion/vessel QFR values are <0.905/0.890 post-DCB therapy, a higher risk of vessel restenosis is potentially predicted at follow-up.
Constriction, Pathologic ; Coronary Angiography ; Coronary Artery Disease/therapy* ; Coronary Restenosis ; Follow-Up Studies ; Fractional Flow Reserve, Myocardial ; Humans ; Pharmaceutical Preparations ; Predictive Value of Tests ; Retrospective Studies ; Treatment Outcome

Coronary Angiography ; Coronary Artery Disease ; Coronary Stenosis ; Coronary Vessels/diagnostic imaging* ; Fractional Flow Reserve, Myocardial ; Heart ; Humans ; Predictive Value of Tests

OBJECTIVE: To evaluate the effect of Danhong Injection (, DH) on the index of microcirculatory resistance (IMR) and myocardial injury in patients with unstable angina undergoing elective percutaneous coronary intervention (PCI). METHODS: Seventy-eight patients with unstable angina were randomly divided into DH group (39 cases) and the control group (39 cases) during elective PCI. Randomization was performed using a random-number table. The DH group received DH at a dosage of 40 mL (mixed with 250 mL saline, covered by a light-proof bag, intravenous drip) during PCI and daily for 7 consecutive days, while the control group only received the same dosage of saline. Both groups received standardized treatment. The IMR and fractional flow reserve (FFR) were measured at maximal hyperemia before and after PCI. Myocardial markers, including myoglobin, creatine kinase (CK), creatine kinase MB (CK-MB), and coronary troponin T (cTnT) values were measured at baseline and 24 h after PCI. RESULTS: Among the 78 patients enrolled, the baseline and procedural characteristics were similar between the two groups. There was no significant difference in pre-PCI myocardial markers and coronary physiological indexes between the two groups. However, post-PCI CK and CK-MB levels in the DH group were significantly lower than those in the control group (111.97 ± 80.97 vs. 165.47 ± 102.99, P=0.013; 13.08 ± 6.90 vs. 19.75 ± 15.49, P=0.016). Post-PCI myoglobin and cTNT-positive tend to be lower in the DH group than in the control group but did not reach statistical significance (88.07 ± 52.36 vs. 108.13 ± 90.94, P=0.52; 2.56% vs.7.69%, P=0.065). Compared with the control group, the post-IMR levels of the DH group tended to decrease, but there was no statistical difference (20.73 ± 13.15 vs. 26.37 ± 12.31, P=0.05). There were no statistical differences in post-FFR in both groups. The peri-procedural myocardial injury of the DH group was significantly lower than that of the control group (2.56% vs. 15.38%, P=0.025). During the 30-d follow-up period, no major adverse cardiovascular events occurred in either group. CONCLUSION This study demonstrated benefit of DH in reducing myocardial injury and potential preserving microvascular function in patients with unstable angina undergoing elective PCI.
Angina, Unstable/drug therapy* ; Drugs, Chinese Herbal ; Fractional Flow Reserve, Myocardial ; Humans ; Microcirculation ; Percutaneous Coronary Intervention ; Pilot Projects ; Treatment Outcome

fractional flow reserve (vFFR) derived from coronary computed tomography angiography (CTA).MATERIALS AND METHODS: We analyzed 100 vessels from 57 patients who had undergone CTA followed by invasive FFR during coronary angiography. Coronary lumen segmentation and three-dimensional reconstruction were conducted using a completely automated algorithm, and parallel computing based vFFR prediction was performed. Lesion-specific ischemia based on FFR was defined as significant at ≤0.8, as well as ≤0.75, and obstructive CTA stenosis was defined that ≥50%. The diagnostic performance of vFFR was compared to invasive FFR at both ≤0.8 and ≤0.75.RESULTS: The average computation time was 12 minutes per patient. The correlation coefficient (r) between vFFR and invasive FFR was 0.75 [95% confidence interval (CI) 0.65 to 0.83], and Bland-Altman analysis showed a mean bias of 0.005 (95% CI −0.011 to 0.021) with 95% limits of agreement of −0.16 to 0.17 between vFFR and FFR. The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were 78.0%, 87.1%, 72.5%, 58.7%, and 92.6%, respectively, using the FFR cutoff of 0.80. They were 87.0%, 95.0%, 80.0%, 54.3%, and 98.5%, respectively, with the FFR cutoff of 0.75. The area under the receiver-operating characteristics curve of vFFR versus obstructive CTA stenosis was 0.88 versus 0.61 for the FFR cutoff of 0.80, respectively; it was 0.94 versus 0.62 for the FFR cutoff of 0.75.CONCLUSION: Our novel, fully automated, on-site vFFR technology showed excellent diagnostic performance for the detection of lesion-specific ischemia.]]>
Angiography ; Bias (Epidemiology) ; Constriction, Pathologic ; Coronary Angiography ; Fractional Flow Reserve, Myocardial ; Humans ; Ischemia ; Patient-Specific Modeling ; Sensitivity and Specificity