Background: Non-invasive fractional flow reserve (FFRCT) derived from coronary computed tomography angiography (CTA) permits hemodynamic evaluation of coronary stenosis and may improve efficiency of assessment in stable chest pain patients. We determined feasibility of FFRCT in the population of acute chest pain patients and assessed the relationship of FFRCT with outcomes of acute coronary syndrome (ACS) and revascularization and with plaque characteristics. Methods: We included 68 patients (mean age 55.8 ± 8.4 years, 71% men) from the ROMICAT II trial who had ≥50% stenosis on coronary CTA or underwent additional non-invasive stress test. We evaluated coronary stenosis and high-risk plaque on coronary CTA. FFRCT was measured in a core laboratory. Results: We found correlation between anatomic severity of stenosis and FFRCT ≤0.80 vs. FFRCT >0.80 (severe stenosis 84.8% vs. 15.2%; moderate stenosis 33.3% vs. 66.7%; mild stenosis 33.3% vs. 66.7% patients). Patients with severe stenosis had lower FFRCT values (median 0.64, 25th-75th percentile 0.50–0.75) as compared to patients with moderate (median 0.84, 25th-75th percentile, p < 0.001) or mild stenosis (median 0.86, 25th-75th percentile 0.78–0.88, p < 0.001). The relative risk of ACS and revascularization in patients with positive FFRCT ≤0.80 was 4.03 (95% CI 1.56–10.36) and 3.50 (95% CI 1.12–10.96), respectively. FFRCT ≤0.80 was associated with the presence of high-risk plaque (odds ratio 3.91, 95% CI 1.55–9.85, p = 0.004) after adjustment for stenosis severity. Conclusion: Abnormal FFRCT was associated with the presence of ACS, coronary revascularization, and high-risk plaque. FFRCT measurements correlated with anatomic severity of stenosis on coronary CTA and were feasible in population of patients with acute chest pain.
- Acute coronary syndrome
- Coronary computed tomography angiography
- Non-invasive cardiac testing
- Non-invasive fractional flow reserve
- Risk stratification
- Stress test