Clinical Use of CT-Derived Fractional Flow Reserve in the Emergency Department.
OBJECTIVES
This study sought to examine the feasibility, safety, clinical outcomes, and costs associated with computed tomography-derived fractional flow reserve (FFRCT) in acute chest pain (ACP) patients in a coronary computed tomography angiography (CTA)-based triage program.


BACKGROUND
FFRCT 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 FFRCT were studied. FFRCT ≤0.80 was considered positive for hemodynamically significant stenosis.


RESULTS
Among 555 patients, 297 underwent coronary CTA and FFRCT (196 negative, 101 positive), whereas 258 had coronary CTA only. The rejection rate for FFRCT 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 FFRCT groups (4.3% vs. 2.7%; p = 0.310). Diagnostic failure, defined as discordance between the coronary CTA or FFRCT 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 FFRCT when revascularization was deferred. Negative FFRCT was associated with higher nonobstructive disease on invasive coronary angiography (56.5%) than positive FFRCT (8.0%) and coronary CTA (22.9%) (p < 0.001). There was no difference in overall costs between the coronary CTA and FFRCT groups ($8,582 vs. $8,048; p = 0.550).


CONCLUSIONS
In ACP, FFRCT is feasible, with no difference in major adverse cardiac events and costs compared with coronary CTA alone. Deferral of revascularization is safe with negative FFRCT, which is associated with higher nonobstructive disease on invasive angiography.
['Chinnaiyan|Kavitha M|KM|', 'Safian|Robert D|RD|', 'Gallagher|Michael L|ML|', 'George|Julie|J|', 'Dixon|Simon R|SR|', 'Bilolikar|Abhay N|AN|', 'Abbas|Amr E|AE|', 'Shoukfeh|Mazen|M|', 'Brodsky|Marc|M|', 'Stewart|James|J|', 'Cami|Elvis|E|', 'Forst|David|D|', 'Timmis|Steven|S|', 'Crile|Jason|J|', 'Raff|Gilbert L|GL|']
D000368:Aged D000787:Angina Pectoris D016507:Cardiology Service, Hospital D000072226:Computed Tomography Angiography D017023:Coronary Angiography D003324:Coronary Artery Disease D023921:Coronary Stenosis D004636:Emergency Service, Hospital D005240:Feasibility Studies D005260:Female D053805:Fractional Flow Reserve, Myocardial D017721:Hospital Costs D006801:Humans D008297:Male D008875:Middle Aged D011237:Predictive Value of Tests D011379:Prognosis D012042:Registries D015203:Reproducibility of Results D012189:Retrospective Studies D014218:Triage
emergency department acute chest pain FFR(CT) coronary CT angiography