Diagnostic Performance of On-Site Computed Tomography Derived Fractional Flow Reserve
on Non-Culprit Coronary Lesions in Patients with Acute Coronary Syndrome
(Therapeutic Development and Bioimaging thematic programmes of the Semmelweis University)
(NVKP-16-1-2016-0017 National Heart Program) Támogató: NKFIH
Szakterületek:
Radiológia, sugárgyógyászat és orvosi képalkotás
Szív és érrendszer
The role of coronary computed tomography angiography (CCTA) derived fractional flow
reserve (CT-FFR) in the assessment of non-culprit lesions (NCL) in patients with acute
coronary syndrome (ACS) is debated. In this prospective clinical study, a total of
68 ACS patients with 89 moderate (30–70% diameter stenosis) NCLs were enrolled to
evaluate the diagnostic accuracy of on-site CT-FFR compared to invasive fractional
flow reserve (FFRi) and dobutamine stress echocardiography (DSE) as reference standards.
CT-FFR and FFRi values ≤ 0.80, as well as new or worsening wall motion abnormality
in ≥2 contiguous segments on the supplying area of an NCL on DSE, were considered
positive for ischemia. Sensitivity, specificity, positive, and negative predictive
value of CT-FFR relative to FFRi and DSE were 51%, 89%, 75%, and 74% and 37%, 77%,
42%, and 74%, respectively. CT-FFR value (β = 0.334, p < 0.001) and CT-FFR drop from
proximal to distal measuring point [(CT-FFR drop), β = −0.289, p = 0.002)] were independent
predictors of FFRi value in multivariate linear regression analysis. Based on comparing
their receiver operating characteristics area under the curve (AUC) values, CT-FFR
value and CT-FFR drop provided better discriminatory power than CCTA-based minimal
lumen diameter stenosis to distinguish between an NCL with positive and negative FFRi
[0.77 (95% Confidence Intervals, CI: 0.67–0.86) and 0.77 (CI: 0.67–0.86) vs. 0.63
(CI: 0.52–0.73), p = 0.029 and p = 0.043, respectively]. Neither CT-FFR value nor
CT-FFR drop was predictive of regional wall motion score index at peak stress (β =
−0.440, p = 0.441 and β = 0.403, p = 0.494) or was able to confirm ischemia on the
territory of an NCL revealed by DSE (AUC = 0.54, CI: 0.43–0.64 and AUC = 0.55, CI:
0.44–0.65, respectively). In conclusion, on-site CT-FFR is superior to conventional
CCTA-based anatomical analysis in the assessment of moderate NCLs; however, its diagnostic
capacity is not sufficient to make it a gatekeeper to invasive functional evaluation.
Moreover, based on its comparison with DSE, CT-FFR might not yield any information
on the microvascular dysfunction in the territory of an NCL.