Background:
The optimal site for measuring computed tomography (CT)-derived fractional flow reserve (FFR
CT
) to detect significant coronary artery disease (CAD) remains unknown. We investigated how diagnostic performance changes with FFR
CT
measurement site.
Methods and Results:
The diagnostic performance of FFR
CT
, measured 1–2 cm distal to the stenosis vs. a far-distal site, in detecting significant CAD with invasive fractional flow reserve ≤0.8 was evaluated in 254 diseased vessels from 146 patients with stable or suspected CAD diagnosed by coronary CT angiography. Receiver operating characteristic curve analysis revealed a significantly larger area under the curve for FFR
CT
measured 1–2 cm distal to the stenosis than at a far-distal site (0.829 vs. 0.791, respectively; P=0.0305). The rate of reclassification of positive FFR
CT
was 19% for measurements made 1–2 cm distal to the stenosis, and diagnostic accuracy for FFR
CT
0.71–0.80 improved from 36% to 58% (P=0.0052). Vessel-based diagnostic accuracy of FFR
CT
1–2 cm distal to the stenosis and at a far-distal site was 75% and 65%, respectively (P<0.0001), with corresponding sensitivity of 87% and 94% (P=0.0039), specificity of 60% and 29% (P<0.0001), a positive predictive value of 73% and 62% (P=0.028), and a negative predictive value of 78% and 79% (P=0.958).
Conclusions:
Our data suggest measuring FFR
CT
1–2 cm distal to the stenosis has better diagnostic performance for detecting physiologically significant CAD.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.