Prospective Comparison of FFR Derived From Coronary CT Angiography With SPECT Perfusion Imaging in Stable Coronary Artery Disease: The ReASSESS Study.

OBJECTIVES

This study sought to compare the per-patient diagnostic performance of coronary computed tomography angiography (CTA)-derived fractional flow reserve (FFR) with that of single-photon emission computed tomography (SPECT), using a fractional flow reserve (FFR) value of ≤0.80 as the reference for diagnosing at least 1 hemodynamically significant stenosis in a head-to-head comparison of patients with intermediate coronary stenosis as determined by coronary CTA.

BACKGROUND

No previous study has prospectively compared the diagnostic performance of FFR and myocardial perfusion imaging by SPECT in symptomatic patients with intermediate range coronary artery disease (CAD).

METHODS

This study was conducted at a single-center as a prospective study in patients with stable angina pectoris (N = 143). FFR and SPECT analyses were performed by core laboratories and were blinded for the personnel responsible for downstream patient management. FFR ≤0.80 distally in at least 1 coronary artery with a diameter ≥2 mm classified patients as having ischemia. Ischemia by SPECT was encountered if a reversible perfusion defect (summed difference score ≥2) or transitory ischemic dilation of the left ventricle (ratio >1.19) were found.

RESULTS

The per-patient diagnostic performance for identifying ischemia (95% confidence interval [CI]), FFR versus SPECT, were sensitivity of 91% (95% CI: 81% to 97%) versus 41% (95% CI: 29% to 55%; p < 0.001); specificity of 55% (95% CI: 44% to 66%) versus 86% (95% CI: 77% to 93%; p < 0.001); negative predictive value of 90% (95% CI: 82% to 98%) versus 68% (95% CI: 59% to 77%; p = 0.001); positive predictive value of 58% (95% CI: 48% to 68%) versus 67% (95% CI: 51% to 82%; p = NS); and accuracy of 70% (95% CI: 62% to 77%) versus 68% (95% CI: 60% to 75%; p = NS) respectively.

CONCLUSIONS

In patients with stable chest pain and CAD as determined by coronary CTA, the overall diagnostic accuracy levels of FFR and SPECT were identical in assessing hemodynamically significant stenosis. However, FFR demonstrated a significantly higher diagnostic sensitivity than SPECT.