Coronary CT Angiographic and Flow Reserve-Guided Management of Patients With Stable Ischemic Heart Disease

Abstract

BackgroundClinical outcomes following coronary computed tomography–derived fractional flow reserve (FFRCT) testing in clinical practice are unknown. ObjectivesThis study sought to assess real-world clinical outcomes following a diagnostic strategy including first-line coronary computed tomography angiography (CTA) with selective FFRCT testing. MethodsThe study reviewed the results of 3,674 consecutive patients with stable chest pain evaluated with CTA and FFRCT testing to guide downstream management in patients with intermediate stenosis (30% to 70%). The composite endpoint (all-cause death, myocardial infarction, hospitalization for unstable angina, and unplanned revascularization) was determined in 4 patient groups: 1) CTA stenosis <30%, optimal medical treatment (OMT), and no additional testing; 2) FFRCT >0.80, OMT, no additional testing; 3) FFRCT ≤0.80, OMT, no additional testing; and 4) FFRCT ≤0.80, OMT, and referral to invasive coronary angiography. Patients were followed for a median of 24 (range 8 to 41) months. ResultsFFRCT was available in 677 patients, and the test result was negative (>0.80) in 410 (61%) patients. In 75% of the patients with FFRCT >0.80, maximum coronary stenosis was ≥50%. The cumulative incidence proportion (95% confidence interval [CI]) of the composite endpoint at the end of follow-up was comparable in groups 1 (2.8%; 95% CI: 1.4% to 4.9%) and 2 (3.9%; 95% CI: 2.0% to 6.9%) (p = 0.58) but was higher (when compared with group 1) in groups 3 (9.4%; p = 0.04) and 4 (6.6%; p = 0.08). Risk of myocardial infarction was lower in group 4 (1.3%) than in group 3 (8%; p < 0.001). ConclusionsIn patients with intermediate-range coronary stenosis, FFRCT is effective in differentiating patients who do not require further diagnostic testing or intervention (FFRCT >0.80) from higher-risk patients (FFRCT ≤0.80) in whom further testing with invasive coronary angiography and possibly intervention may be needed. Further studies assessing the risk and optimal management strategy in patients undergoing first-line CTA with selective FFRCT testing are needed.