Clinical Use of Coronary CTA-Derived FFR for Decision-Making in Stable CAD.
Nørgaard Bjarne L,Hjort Jakob,Gaur Sara,Hansson Nicolaj,Bøtker Hans Erik,Leipsic Jonathon,Mathiassen Ole N,Grove Erik L,Pedersen Kamilla,Christiansen Evald H,Kaltoft Anne,Gormsen Lars C,Mæng Michael,Terkelsen Christian J,Kristensen Steen D,Krusell Lars R,Jensen Jesper M
JACC. Cardiovascular imaging
OBJECTIVES:The goal of this study was to assess the real-world clinical utility of fractional flow reserve (FFR) derived from coronary computed tomography angiography (FFR) for decision-making in patients with stable coronary artery disease (CAD). BACKGROUND:FFR has shown promising results in identifying lesion-specific ischemia. The real-world feasibility and influence on the diagnostic work-up of FFR testing in patients suspected of having CAD are unknown. METHODS:We reviewed the complete diagnostic work-up of nonemergent patients referred for coronary computed tomography angiography over a 12-month period at Aarhus University Hospital, Denmark, including all patients with new-onset chest pain with no known CAD and with intermediate-range coronary lesions (lumen reduction, 30% to 70%) referred for FFR. The study evaluated the consequences on downstream diagnostic testing, the agreement between FFR and invasively measured FFR or instantaneous wave-free ratio (iFR), and the short-term clinical outcome after FFR testing. RESULTS:Among 1,248 patients referred for computed tomography angiography, 189 patients (mean age 59 years; 59% male) were referred for FFR, with a conclusive FFR result obtained in 185 (98%). FFR was ≤0.80 in 31% of patients and 10% of vessels. After FFR testing, invasive angiography was performed in 29%, with FFR measured in 19% and iFR in 1% of patients (with a tendency toward declining FFR-iFR guidance during the study period). FFR ≤0.80 correctly classified 73% (27 of 37) of patients and 70% (37 of 53) of vessels using FFR ≤0.80 or iFR ≤0.90 as the reference standard. In patients with FFR >0.80 being deferred from invasive coronary angiography, no adverse cardiac events occurred during a median follow-up period of 12 (range 6 to 18 months) months. CONCLUSIONS:FFR testing is feasible in real-world symptomatic patients with intermediate-range stenosis determined by coronary computed tomography angiography. Implementation of FFR for clinical decision-making may influence the downstream diagnostic workflow of patients. Patients with an FFR value >0.80 being deferred from invasive coronary angiography have a favorable short-term prognosis.
Clinical Use of CT-Derived Fractional Flow Reserve in the Emergency Department.
Chinnaiyan Kavitha M,Safian Robert D,Gallagher Michael L,George Julie,Dixon Simon R,Bilolikar Abhay N,Abbas Amr E,Shoukfeh Mazen,Brodsky Marc,Stewart James,Cami Elvis,Forst David,Timmis Steven,Crile Jason,Raff Gilbert L
JACC. Cardiovascular imaging
OBJECTIVES:This study sought to examine the feasibility, safety, clinical outcomes, and costs associated with computed tomography-derived fractional flow reserve (FFR) in acute chest pain (ACP) patients in a coronary computed tomography angiography (CTA)-based triage program. BACKGROUND:FFR is useful in determining lesion-specific ischemia in patients with stable ischemic heart disease, but its utility in ACP has not been studied. METHODS:ACP patients with no known coronary artery disease undergoing coronary CTA and coronary CTA with FFR were studied. FFR ≤0.80 was considered positive for hemodynamically significant stenosis. RESULTS:Among 555 patients, 297 underwent coronary CTA and FFR (196 negative, 101 positive), whereas 258 had coronary CTA only. The rejection rate for FFR was 1.6%. At 90 days, there was no difference in major adverse cardiac events (including death, nonfatal myocardial infarction, and unexpected revascularization after the index visit) between the coronary CTA and FFR groups (4.3% vs. 2.7%; p = 0.310). Diagnostic failure, defined as discordance between the coronary CTA or FFR results with invasive findings, did not differ between the groups (1.9% vs. 1.68%; p = NS). No deaths or myocardial infarction occurred with negative FFR when revascularization was deferred. Negative FFR was associated with higher nonobstructive disease on invasive coronary angiography (56.5%) than positive FFR (8.0%) and coronary CTA (22.9%) (p < 0.001). There was no difference in overall costs between the coronary CTA and FFR groups ($8,582 vs. $8,048; p = 0.550). CONCLUSIONS:In ACP, FFR is feasible, with no difference in major adverse cardiac events and costs compared with coronary CTA alone. Deferral of revascularization is safe with negative FFR, which is associated with higher nonobstructive disease on invasive angiography.
Fractional Flow Reserve Derived from Coronary Computed Tomography Angiography Safely Defers Invasive Coronary Angiography in Patients with Stable Coronary Artery Disease.
Rabbat Mark,Leipsic Jonathon,Bax Jeroen,Kauh Brian,Verma Rina,Doukas Demetrios,Allen Sorcha,Pontone Gianluca,Wilber David,Mathew Verghese,Rogers Campbell,Lopez John
Journal of clinical medicine
OBJECTIVES:In the United States, the real-world feasibility and outcome of using fractional flow reserve from coronary computed tomography angiography (FFR) is unknown. We sought to determine whether a strategy that combined coronary computed tomography angiography (CTA) and FFR 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 FFR and 44 control patients who underwent CTA alone. Lesions with 30-90% diameter stenoses were considered of indeterminate hemodynamic significance and underwent FFR. Nadir FFR ≤ 0.80 was positive. The rate of patients having ICA, revascularization and major adverse cardiac events were recorded. RESULTS:Using coronary CTA and selective FFR, 121 patients (32%) had at least one vessel with ≥50% diameter stenosis; 67/121 (55%) patients had at least one vessel with FFR ≤ 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 FFR ≤ 0.80; 8/90 (9%) underwent ICA; and five were revascularized. In our institutional practice, compared to coronary CTA alone, coronary CTA with selective FFR reduced the rates of ICA (45% vs. 80%) for those with obstructive CAD. Using coronary CTA with selective FFR, no major adverse cardiac events occurred over a mean follow-up of 440 days. CONCLUSION:FFR safely deferred ICA in patients with CAD of indeterminate hemodynamic significance. A high proportion of those who underwent ICA were revascularized.
The influence of image quality on diagnostic performance of a machine learning-based fractional flow reserve derived from coronary CT angiography.
Xu Peng Peng,Li Jian Hua,Zhou Fan,Jiang Meng Di,Zhou Chang Sheng,Lu Meng Jie,Tang Chun Xiang,Zhang Xiao Lei,Yang Liu,Zhang Yuan Xiu,Wang Yi Ning,Zhang Jia Yin,Yu Meng Meng,Hou Yang,Zheng Min Wen,Zhang Bo,Zhang Dai Min,Yi Yan,Xu Lei,Hu Xiu Hua,Liu Hui,Lu Guang Ming,Ni Qian Qian,Zhang Long Jiang
OBJECTIVE:To investigate the effect of image quality of coronary CT angiography (CCTA) on the diagnostic performance of a machine learning-based CT-derived fractional flow reserve (FFR). METHODS:This nationwide retrospective study enrolled participants from 10 individual centers across China. FFR analysis was performed in 570 vessels in 437 patients. Invasive FFR and FFR values ≤ 0.80 were considered ischemia-specific. Four-score subjective assessment based on image quality and objective measurement of vessel enhancement was performed on a per-vessel basis. The effects of body mass index (BMI), sex, heart rate, and coronary calcium score on the diagnostic performance of FFR were studied. RESULTS:Among 570 vessels, 216 were considered ischemia-specific by invasive FFR and 198 by FFR. Sensitivity and specificity of FFR for detecting lesion-specific ischemia were 0.82 and 0.93, respectively. Area under the curve (AUC) of high-quality images (0.93, n = 159) was found to be superior to low-quality images (0.80, n = 92, p = 0.02). Objective image quality and heart rate were also associated with diagnostic performance of FFR, whereas there was no statistical difference in diagnostic performance among different BMI, sex, and calcium score groups (all p > 0.05, Bonferroni correction). CONCLUSIONS:This retrospective multicenter study supported the FFR as a noninvasive test in evaluating lesion-specific ischemia. Subjective image quality, vessel enhancement, and heart rate affect the diagnostic performance of FFR. KEY POINTS:• FFRcan be used to evaluate lesion-specific ischemia. • Poor image quality negatively affects the diagnostic performance of FFR. • CCTA with ≥ score 3, intracoronary enhancement degree of 300-400 HU, and heart rate below 70 bpm at scanning could be of great benefit to more accurate FFRanalysis.
Impact of machine learning-based coronary computed tomography angiography fractional flow reserve on treatment decisions and clinical outcomes in patients with suspected coronary artery disease.
Qiao Hong Yan,Tang Chun Xiang,Schoepf U Joseph,Tesche Christian,Bayer Richard R,Giovagnoli Dante A,Todd Hudson H,Zhou Chang Sheng,Yan Jing,Lu Meng Jie,Zhou Fan,Lu Guang Ming,Jiang Jian Wei,Zhang Long Jiang
OBJECTIVES:This study investigated the impact of machine learning (ML)-based fractional flow reserve derived from computed tomography (FFR) compared to invasive coronary angiography (ICA) for therapeutic decision-making and patient outcome in patients with suspected coronary artery disease (CAD). METHODS:One thousand one hundred twenty-one consecutive patients with stable chest pain who underwent coronary computed tomography angiography (CCTA) followed ICA within 90 days between January 2007 and December 2016 were included in this retrospective study. Medical records were reviewed for the endpoint of major adverse cardiac events (MACEs). FFR values were calculated using an artificial intelligence (AI) ML platform. Disagreements between hemodynamic significant stenosis via FFR and severe stenosis on qualitative CCTA and ICA were also evaluated. RESULTS:After FFR results were revealed, a change in the proposed treatment regimen chosen based on ICA results was seen in 167 patients (14.9%). Over a median follow-up time of 26 months (4-48 months), FFR ≤ 0.80 was associated with MACE (HR, 6.84 (95% CI, 3.57 to 13.11); p < 0.001), with superior prognostic value compared to severe stenosis on ICA (HR, 1.84 (95% CI, 1.24 to 2.73), p = 0.002) and CCTA (HR, 1.47 (95% CI, 1.01 to 2.14, p = 0.045). Reserving ICA and revascularization for vessels with positive FFR could have reduced the rate of ICA by 54.5% and lead to 4.4% fewer percutaneous interventions. CONCLUSIONS:This study indicated ML-based FFR had superior prognostic value when compared to severe anatomic stenosis on CCTA and adding FFR may direct therapeutic decision-making with the potential to improve efficiency of ICA. KEY POINTS:• ML-based FFR shows superior outcome prediction value when compared to severe anatomic stenosis on CCTA. • FFR noninvasively informs therapeutic decision-making with potential to change diagnostic workflows and enhance efficiencies in patients with suspected CAD. • Reserving ICA and revascularization for vessels with positive FFR may reduce the normalcy rate of ICA and improve its efficiency.
Coronary flow impairment in asymptomatic patients with early stage type-2 diabetes: Detection by FFR.
Mrgan Monija,Nørgaard Bjarne Linde,Dey Damini,Gram Jørgen,Olsen Michael Hecht,Gram Jeppe,Sand Niels Peter Rønnow
Diabetes & vascular disease research
PURPOSE:To determine the occurrence of physiological significant coronary artery disease (CAD) by coronary CT angiography (CTA) derived fractional flow reserve (FFR) in asymptomatic patients with a new diagnosis (<1 year) of type-2 diabetes mellitus (T2DM). METHODS:FFR-analysis was performed from standard acquired coronary CTA data sets. The per-patient minimum distal FFR-value (d-FFR) in coronary vessels (diameter ⩾1.8 mm) was registered. The threshold for categorizing FFR-analysis as abnormal was a d-FFR ⩽0.75. Total plaque volume and volumes of calcified plaque, non-calcified plaque, and low-density non-calcified plaque (LD-NCP) were assessed by quantitative plaque analysis. RESULTS:Overall, 76 patients; age, mean (SD): 56 (11) years; males, (%): 49(65), were studied. A total of 57% of patients had plaques. The d-FFR was ⩽0.75 in 12 (16%) patients. The d-FFR, median (IQR), was 0.84 (0.79-0.87). Median (range) d-FFR in patients with d-FFR ⩽0.75 was 0.70 (0.6-0.74). Patients with d-FFR⩽0.75 versus d-FFR >0.75 had numerically higher plaque volumes for all plaques components, although only significant for the LD-NCP component. CONCLUSION:Every sixth asymptomatic patient with a new diagnosis of T2DM has hemodynamic significant CAD as evaluated by FFR Flow impairment by FFR was associated with coronary plaque characteristics.
Fractional flow reserve derived from coronary computed tomography angiography: diagnostic performance in hypertensive and diabetic patients.
Eftekhari Ashkan,Min James,Achenbach Stephan,Marwan Mohamed,Budoff Matthew,Leipsic Jonathon,Gaur Sara,Jensen Jesper Møller,Ko Brian S,Christiansen Evald Høj,Kaltoft Anne,Bøtker Hans Erik,Jensen Jens Flensted,Nørgaard Bjarne Linde
European heart journal cardiovascular Imaging
Aims:Fractional flow reserve (FFR) derived from coronary computed tomography (FFRCT) has high diagnostic performance in stable coronary artery disease (CAD). The diagnostic performance of FFRCT in patients with hypertension (HTN) and diabetes (DM), who are at risk of microvascular impairment, is not known. Methods and results:We analysed the diagnostic performance of FFRCT, in patients (vessels) with DM (n = 16), HTN (n = 186), DM + HTN (n = 58) vs. controls (n = 107) with or with suspected CAD. Patients (vessels) were further divided according to left ventricular mass index (LVMI) tertiles. Reference standard was invasively measured FFR ≤0.80. Per-patient diagnostic accuracy (95% CI) in control patients was 71.7% (61.6-81.8) vs. 79.3 (74.0-85.0) (P = 0.12), 75.0% (47.6-92.7) (P = 0.52), and 75.9% (62.8-86.1) (P = 0.39) in patients with HTN, DM, and HTM + DM, respectively. There was no difference in discrimination of ischaemia by FFRCT between groups. On a per-vessel level, there was no significant difference in diagnostic performance or discrimination of ischaemia by FFRCT between groups. There was a decline in both per-patient and -vessel diagnostic specificity of FFRCT in the upper LVMI tertile when compared with lower tertiles; however, discrimination of ischaemia by FFRCT was unaltered across LVMI tertiles. Conclusion:The diagnostic performance of FFRCT is independent of the presence of HTN and DM. FFRCT is a robust method in a broad stable CAD population, including patients at high risk for microvascular disease.